Study case 1 Essay Example | Topics and Well Written Essays - 750 words

Study case 1 - Essay Example It is regarded as morally wrong unless that person is your wife. The man declined to remove his pants for the X-ray due to his protestant stand which does not allow females to see their private parts and this also the main reason as to why he refused to cover himself with a towel. Most of them would even prefer to die than to be treated by a female doctor which does not make sense at all. Just because, this female doctor is going to see your private parts does not mean she is going to do anything with them, all she is interested in is treating you and therefore fulfilling her duty at work (Nam, 11). Most of our cultures misguide us by the things they make us believe, and they may destroy us rather than build us. Religion is supposed to build and unite us but not to tear us apart (Nam, 11). Therefore, everybody is supposed to respect each other, and that includes their religion too. We all believe in something even if not God. We believe He exists though nobody can really prove that he does, we all therefore want the religion we believe in to be superior to the others. However, personal views on religion should be banned in all healthcare facilities and clinics as they helps in promoting unity. If personal views are brought up in the health facilities, it may bring up religious conflicts which bring a poor working environment. This is the main reason as to why one has to compromise his or her religious views for the sake of healthcare. It is very unfair for one to think of banning the religious garb or the jewelry to the healthcare yet they do not know what these things mean to these people. It is their belief that is being disrespected and therefore mocking their belief (Nam, 10). What they do not ask themselves is how they would feel if they were in their position or what they would do if the same was being done to them. But no, of course they did not ask

Reflective Essay Example | Topics and Well Written Essays - 1000 words - 1

Reflective - Essay Example Much of this confidence came from the level of cooperation that I had with the unit manager, under whom I was working. Taking permission to start such a project was not that difficult specially that the unit manger is very supportive and the ER consultants are very enthusiastic to do so. The very first of the processes for working on the project was to get a proposal ready. So on the 13th of December, 2012, I submitted my proposal to the manager about education for public about Triage process. Though I thought this was going to be a very useful area to research, the manager disagreed with it because one of the emergency consultants started that project and was almost done. I felt disappointed because I had to start searching for another topic and time get shorter. I went to my manager again and we had a discussion to find another topic. Using his experience at the workplace over the last seven years, the manager showed clearly that there were different goals that he had, which were m ore suitable to our working conditions than I had given. I was made to evaluate some of these goals and out of it, landed on one of them, which would later become the research topic. The research problem was based on a problem identified in the immediate environment of the hospital. It was observed from the emergency department that the number of pediatric attending A/E room is high so we decided to see why and then we started the project of education. Once I got the approval from the manager I was relaxed and I started to do my project. I started the actual action towards the project two days after I had received the final approval on the topic from my supervisor and this was on the 20th of December, 2012. The very first action taken by me was to start looking for secondary sources of information to prepare my research questions and themes for the literature review. First I started with the pamphlet which has information about fever management for children at home before attending accident emergency. After all necessary information was collected I went to the marketing department for an approval to start undertaking the education section for the patients. But yet again, I will receive a shock to the success and smooth progress of the project as I was informed when I went to marketing department and find out that I still needed approval from the pediatric consultant who was not available in the hospital by that time. This made me highly uneasy and upset because I started feeling bad about the success of the project again because I felt the time was delaying. It is for this reason that I say that actions depend on situations because whenever things went right, my actions were positive and joyful. On 25th of December, 2012 when I was informed that the paediatric consultant had travelled, I became very disturbed and thought that some people wanted to sabotage the progress of my project. But after the consultant returned in two weeks, I found that the situation wa s nothing like what I thought about her or the people in the department. After 2 weeks she came back and we discussed the project together and she welcomed the idea and supported me to do so. Once I got the approval I started the data collection over a period of 2 weeks. I some faced problems at first with data collection because most of the parent when they bring their children to the

Italian Renaissance Art Essay Example | Topics and Well Written Essays - 1000 words

Italian Renaissance Art - Essay Example Neo-Platonism seeks the existence or relation of the ideal or The One in the human life. This is what renaissance artists such as Botticelli, Leonardo, Raphael and Michelangelo are trying to depict through allegories in their art. Botticelli, to start with, was one of the early artists to reflect neo-Platonism in his works. He used symbols and figures from pre-Christian beliefs to convey neo-Platonist ideas. Take one of his paintings for example, the Primavera which translates as spring. This painting includes nine figures from Classical mythology. On the center is Venus coupled with Cupid. On their right are Zephyr, Chloris and Flora and on the left are Mercury and the three graces. The figures on the right represent the coming of spring, nature and its beauty. In contrast to that are the figures on the left which represent reason and the pleasures of human life. These are two different points which harmonizes on the center figure. Being a prime mover of neo-Platonism in art, Botticelli’s techniques are yet to be developed. The symbols he portrayed are literal and, for the educated and elite, too obvious. But even at this point he has already defined the essentials for neo-Platonism, the fusion nature and grace. Then came Leonardo da Vinci and Raphael. They both relate ideas in their own way. Leonardo focused on structure and Raphael on evoking emotions. Leonardo is known on our time as an inventor and a scientist, and these qualities can be seen through his art. He was a master of proportions, shading, depth and ways of making his work look â€Å"real†. Even outside of the standard of beauty as long as his work looks alive, for him, achieves the harmony of neo-Platonism. Raphael took it further by involving and evoking emotions through his paintings. He was also interested with philosophy which shows that he is an artist as a scholar. This is seen on School of Athens which shows Plato and Aristotle along with other philosophers. On this painting, Plato is seen pointing heavenward explaining the facts of the universe while Aristotle points downward stating the society and the views of the world. Both of them are supervised by the statues of Apollo and Minerva, ensuring truth and wisdom respectively. Towards the end of the renaissance there came the meeting point of pagan beliefs and the Christian cultures. This was when Michelangelo lived and experienced neo-Platonism as a whole. Not as visual parts nor as philosophical representations but as its entirety. But this also meant the end for neo-Platonism for Michelangelo accepted spirituality towards the end. His representations and the transition can be seen on the paintings on the Sistine chapel. On the earlier paintings like The Creation of Adam, his interest on the beauty and elegance is apparent. His poetry also reflects his belief in the divine origin of beauty. But through time and the influence of the Roman Catholic Church, Michelangelo lost his interest in physical beauty and no longer believed in its representation of spiritual excellence. Later painting shows more Christian representation loosing detail and grace. He eventually fully lost his interest and decided to no longer paint becoming guilty of his love for physical beauty. In a way this was the end of neo-Platonism for Italian renaissance art. 2. The common denominator among Della Francesca, Alberti and Mantegna are their contribution to the perspective aspect of renaissance paintings. Each has professions other than being artist and this variety of expertise made the development possible. Della Francesca, aside from being an artist, was a mathematician. He studied and wrote books which involved arithmetic, algebra and geometry. One of his books is the On Perspective for Painting. He also made innovations on solid or three-dimensional

Group Signature Essay Example for Free

Group Signature Essay Group signature schemes allow a member of group to sign a message on behalf of the group anonymously and in unlinkable passion. However, a designated group manager can easily identify the signer. The signer of a valid group signature is needed to be a member of the group. These features are important in some specialized applications. This scheme is to be used in electronic business transaction. The scheme needed to satisfy six properties to be secured. These are unforgeability, anonymity, unlinkability, no framing, traceability and coalition-resistant. Mathematicians and computer scientist continues their studies to improve their proposed schemes. It is to satisfy the six properties with no doubt. Key words: group signature, unforgeability, unlinkability, no framing, traceability, coalition-resistant Group Signature Introduction The process, in which certain anonymity is needed to perform a task in spite of a collection of people or groups, is the based the concept of group signatures is born. Chaum and van Heyst first introduced this. The concept of group signature provides a member of group to sign certain messages anonymously and unlinkably on behalf of the whole group. On the other hand, a designated group manager has power to unveil the identity of the signer in cases of dispute. A group signature is verified through a series of algorithm to ensure that the signer is a member of that certain group. However, the group’s structure is still concealed and the signer can only be identified if the necessity occurs. With this features, the group signature scheme have potential application. Such applications are needed in electronic transaction that needed to be signed. The anonymity of the signer is essential to prevent others to see organizational structure of the signatory group. A group signature is needed to be secured to preserve the unlinkability and anonymity. A group signature scheme must satisfy the six properties. One is unforgeability. This is the property which ensures that only members of the group can sign on behalf of the group. This feature is necessary to make sure that invalid members or revoked members cannot sign on behalf of the group. This provides a way on which if there is dispute in a valid group signature, the group manager can easily find out who the signer is or it can be concluded that it is a member of the group when the message is signed. Number two is anonymity. This feature assures the members of the group that the identification of the signer will be hard except to the group manger. This is one of the main features of group signature. It conceals the identity of the signer. Consequently, it conceals the organizational structure of the group. The third one is unlinkability. This is feature which tells that determining whether two valid signatures were generated by a common member will be hard. This feature is necessary to go with anonymity of the signer. Since if you can identify two valid signatures coming from single member then it will easy to identify the signer. Number four is no framing. This is ensures that no member or the group manager can sign on behalf of other members. This is necessary to protect any member from a wrong identification when a dispute occurs. The fifth one is traceability. The traceability means that a group manager will be able to open a valid signature and determine the identity of member who signed it. It means that in a dispute, the group manager can easily identify the signer. Additionally, this property does not the possibility of not identifying the signer. The last one is coalition-resistant. This means a subset of members of the group or even the whole group cannot generate a valid signature on which the group manger cannot link on one of the members of the subset group. This ensures that a certain valid group signature can always be associated with a single member of the group not with subset of the group. There are many studies which ensure that the six properties are satisfied. There are many proposals of which contains algorithm that is claimed to satisfy the six properties. There are some summaries of articles of proposals and advancement in group signature. The reader would find these summaries of articles to contain dispute of other schemes. Security Remarks on a Group Signature Scheme with Member Deletion The Kim-Lim-Lee group signature scheme is scheme which claims to have a member deletion function, security and unlinkability. These claims are put into consideration because it is found to be unsecured and linkable. This will present some remarks which will prove the unsecurity and linkability of the Kim-Lim-Lee group signature scheme (Wang et al. , n. d. ). This scheme consists of different stages. These are system set up, join, delete, sign verify and open phases (Wang et al. , n. d. ). The system set-up is done by the membership manager in which he sets parameters and compute for secret and public keys. At the same time, the revocation manager selects his secret key and then computes and publishes his own public key (Wang et al. , n. d. ). At the join stage, the user who wants to join the group need undergo an interactive protocol on which he is assigned to a generated membership key and given the public key. Additionally, current members of the group update their membership key (Wang et al. , n. d. ). The deletion stage happens when a member is voluntary or involuntary leaving the group. The membership manger performs a series of algorithm and updates the group’s public key. He then computes fro the renewal public key. Here, the membership manager publishes the two new public keys. Then, every valid members of the group updates his secret property key (Wang et al. , n. d. ). In the sign stage, a member needed to sign some message. The member submits his membership key and his secret to generate the group signature (Wang et al. , n. d. ). The group signature generated in the sign stage is then subjected to verification. The verifier then uses a series of computation to verify the signature. The verification will yield a result which indicates if a valid member of the group signed it or not (Wang et al. , n. d. ). In the case of dispute, the open protocol is done. The open protocol is done to trace the identity of the signer. Only the group manager can do this (Wang et al. , n. d. ). The process of which the Kim-Lim-Lee group signature scheme under is found to be unsecured. This is due to proven accounts its security parameters is lacking in some cases. It is proven the two parameters used in the scheme are not sufficient to ensure absolute security (Wang et al. , n. d. ). The unlinkability claim of this scheme is also taken to account. The unlikability claim was proven wrong. The group signature scheme of Kim, Lim and Lee is prove to be linkable. It is proven that it easy to associate a given group signature to member of a group. This is due to invariance in the group signatures within time and even in all time periods. It means two signatures can be traced back to signer simple computational analysis (Wang et al. , n. d. ). A member deletion stage is then scrutinized by disproving the claim of which a deleted member cannot generate a valid group signature. The problem with this is identified in the process of the updating the members secret key. It is said a deleted member can simply update his secret along with other valid members since he can compute for a member secret in a given time. At the same time, a new member can get a version of his secret membership in the past time when is not yet a member (Wang et al. , n. d. ). Thus, the security of the Kim-Lim-Lee group signature scheme is proven to unreliable and unsecured. It is needed to revised and improved to satisfy the needs for a good group signature scheme (Wang et al. , n. d. ). An Efficient ID-Based Group Signature Scheme The ID-based signature scheme is proposed to be more efficient than other predecessors. The scheme is based on the process of the ID-based electronic signature. The identity-based signature uses publicly known identifier such as IP address, e-mail address and other identifiers. It is use to compute for public key component of the pair use for digital signatures, encryptions, and key agreement. The private key is computed by a trusted authority. This scheme is aimed to have better efficiency and to cope with large number of members in a group (Popescu, 2000, 29-35). The identity based signature scheme is done in several phases. The set-up process is done by the trusted authority which leads to the extract phase in which the user provide the ID. The ID becomes the public key and the trusted authority returns a private key which is needed to make for the signing protocol (Popescu, 2000, 29-35). The verification of an identity based signature is done by inputting the message with the signature, the parameters and a public key ID. The verify stage outputs the validity of the signature (Popescu, 2000, 29-35). There is another type of ID-based signature which is from the pairings on elliptical curves. This scheme is done to improve the efficiency of the ID-based signature processes. It is basically similar with the conventional one. However, the computations are different and more appropriate for large number of users (Popescu, 2000, 29-35). The scheme use in ID-based signature is put into the context of group signatures. The set-up procedures are similar with the ID-base signature but the group public key and the secret key is computed differently. Compared to other group signature schemes the set-up stage is done more efficiently (Popescu, 2000, 29-35). In the join stage, the user sends the ID to the group manager and the group manager computes for the membership certificate and secretly sends it to the new member in a secure private channel. This process is more efficient since the stages were reduced. However, the security is still intact because of the process in the set-up stage that lessens the work at other stages (Popescu, 2000, 29-35). The signing stage makes use of the public and private key pair which was generated by the user himself. The pair key is use to compute and generate the group signature. It is combined with a random number for it to be anonymous and unlinkable (Popescu, 2000, 29-35). The verify stage is split in the two parts. The first part is that it verifies if the signer is definitely a member of the group. If the signature generated by the group is valid and it is signed by a member of the group, the second stage commences. It is to verify that a member signed the group signature and not the group manager (Popescu, 2000, 29-35). The open stage is done when there is time that the signer needed to be identified. Like other schemes, the group manager can only do this. This process is very easy for the group manager since the manager knows the identity of the user who is associated with the group signature. This is because in the join stage the bind between the user and the manager was forged (Popescu, 2000, 29-35). The ID-based group signature scheme keeps the security properties of a good group signature in tact. The identity based signature guarantees some the properties and the added processes in the group signature scheme made other necessary security measures (Popescu, 2000, 29-35). The ID-based group signature from elliptic curves was derived from the identity based signature scheme. This scheme can handle a large number of members in a group without compromising the security and the efficiency of the process involved. However, the disadvantage is that the efficiency of the group signature is based on the efficiency of the identity based signature scheme it uses (Popescu, 2000, 29-35). Practical and Provably Secure Coalition-Resistant Group Signature Scheme Group signature concept is dual to the identity escrow which this scheme uses to create a coalition-resistant group signature scheme. The identity escrow can replace the membership certificate which other group signature uses. The use of identity escrow in group signatures can be regarded as group-identification scheme with revocable anonymity. This is scheme is just the second coalition-resistant group signature scheme which is an improve version of the first (Ateniese et al. , 2000, 255-270). This group signature scheme differs to other scheme in the efficiency of the join process. The user needs not to send his secret to the group manager not like other conventional schemes. The feature of which the user sends secrets to the group manager is found to be susceptible to attacks. This scheme eliminates such possibility and is proven to be coalition resistant even against adaptive adversaries (Ateniese et al. , 2000, 255-270). The model use by this scheme is somewhat similar to conventional group signature schemes. The group signature scheme undergoes several phases. These phases are the setup, join, sign, verify and in some cases open. Like the other group signature schemes every phase has algorithm need to be follow to ensure the properties to be intact (Ateniese et al. , 2000, 255-270). They only differ in the sign process as this scheme provides an interactive process between the signer and the verifier. The process is derived by replacing the call of the user to the hash function to the call to the verifier. The interactive protocol between the user and the verifier gives way to a more secure group signature (Ateniese et al. , 2000, 255-270). This scheme was proposed to have two major advantages over other conventional group signature schemes. One is the join process is more efficient than other scheme. This is since the new member just needed to provide proofs of knowledge of discrete logarithms in contrast with other schemes which requires new members to prove that a number is a product of two primes. The other advantage is that join process is more secure since it does not require the new member to send his membership secrets which is required in other schemes. Additionally, the property of being coalition resistant against adaptive is in fact an extra advantage (Ateniese et al. , 2000, 255-270). Generally, this scheme surpasses all other schemes created before it in terms of performance and security and it is proven to be coalition-resistant. It is because of the feature like spliting the group manager in two, a membership manager and a revocation manager (Ateniese et al. , 2000, 255-270). Group Signature Scheme with Revocation A number of group signature schemes had been proposed. However, these schemes don’t consider a growing membership or shrinking membership as well. In the real world, a member of a group can join, voluntary or be expelled from the group in any time. This done by other proposed schemes by not issuing changes to public keys and re-issuing group memberships. Thus, Popescu, Noje, Bede and Mang from the University of Oradea proposed a group signature scheme with revocation (Popescu et al. , 2003). There are other several group signature schemes that were proposed. However, these other proposed schemes lacked in efficiency and other others in security. There is a scheme which was proved to be efficient and secured but it requires time periods which any and all verifiers must know, thus requires more time in the verification stage (Popescu et al. , 2003). They proposed a group signature scheme in which every step or phase is different from other group signature schemes. It consists of different computational procedures (Popescu et al. , 2003). In the setup procedure, the group manager needs to undergo several steps which will yield the public key P, the secret key S and a group membership certificate consisting of two integers X and ? satisfying a certain equation which relates the two integers (Popescu et al. , 2003). In the join stage, a user wants to join a group. The scheme requires a secure and private communication between the group manager and the user to protect the anonymity of the user. The user chooses an element from a set formed by the parameters set by the group manager. From the chosen element the user will compute and send an ID which he needs to prove before he chooses a random number from a designated set. The group and the user computes and send computation results to each other until the user received his membership certificate. After this process, only the user knows his membership certificate and that the group manager only registers the ID of the user in the data base which was obtained in the first computation (Popescu et al. , 2003). The user is then allowed to sign to represent the whole group. At the signing process, the user can create a group signature inside a message by computation. The computation starts with the computation with his membership certificate. The user is the only one who knows his membership certificate so he remains anonymous to others. The group signature is then sent to the verifier for verification (Popescu et al. , 2003). In the verification phase, the resulting signature inside a message is verified through a series of computations in which the check the proof of equality between the double discrete logarithm of F (a part of the signature) and the discrete logarithm of D’s representation base on the element of the set that the group manager defined in the setup process. If it is equal the verifier concludes that the user who signed the group signature is a member of the group (Popescu et al. , 2003). When the time comes when it is needed to know who signs the message containing the group signature. He can do this by checking the correctness of the group signature. If it is incorrect, the group managers abort the process. Other wise, the group manager recovers a certain ID in the database and prove that the ID is relative to the D (a part of the group signature) (Popescu et al. , 2003). When a member of the leaves the group the group performs a series of algorithm which will result to the publication of the revocation status of a user in the Certificate Revocation List which was assumed to be available at all times in a well-known public servers. The CRL is also assumed to be signed by the issuer, the group manager or other trusted party (Popescu et al. , 2003). In this scheme, there are strong considerations in the security as provided different calculations that ensure the impossibility of some scenarios that compromises the anonymity of the members of the group. Furthermore, the cost of the revoke process is linear to the number of revoked members. Additionally, this scheme provides fixed signature size and constant work of the signers which makes it more practical than other group signature schemes. However, the opening process of this scheme can result to hundred of exponentiations per signature due to the proofs involving double discrete logarithms (Popescu et al. , 2003). Quasi-Efficient Revocation of Group Signatures This scheme is specified to address the inefficient and unsecured revocation methods use by other group signature scheme. The security of a group signature is not met if it uses an inefficient way of revocation. Additionally, the quasi-efficient revocation methods provide a practical public keys and signatures (Ateniese et al, n. d. ). The importance of a good revocation method is seen in groups with shrinking number of members. The security of the group is compromised if the revocation process is not well established since a revoked member can still sign in spite of the group (Ateniese et al, n. d. ). There are a number of group signature scheme which provides good revocation methods but they need to use synchronized clocks and the signature size is relative to the number of revoked members. The use of loosely synchronized clocks in revocation of membership needs to notify all existing members about the revocation. It modifies the membership certificate of all members and consequently, affects the size of group signature generated (Ateniese et al, n. d. ). This revocation method is made in line with the ACJT signature scheme. The revocation methods can only be done by revising the backward unlinkability to unconditional unlinkability. However, the easiest way of revocation is reissuing of the membership certificates and regenerating the public key. This costs a lot of work to the group manager and the members since they have to repeat parts of the join process. Additionally, the verifiers need to be informed of the changes. However, there is a way to eliminate this inconvenience by generating public keys and membership certificates automatically. This is will eliminate the interactive process between the manager and the members. On the other hand, it has impracticality in the process since it requires issuance of new certificates to existing members (Ateniese et al, n. d. ). The efficient way to overcome this problem is to avoid issuing new membership certificates in the event of revocation of a member. This is done in some scheme in which they use a Certificate Revocation List (CRL). However, the scheme’s group signature presented contains an encrypted version of the CRL. It is necessary to prevent the linking of the group signatures. However, the problem is resolved here by including the latest CRL to the group public key in which the unlinkability is preserved (Ateniese et al, n. d. ). The efficiency of this scheme is measured by the size of the signature, the signer cost, verifier cost, CRL size, and the CRL issuance cause. This scheme had passed all requirements since it minimizes the size of the signature as it fixed, the cost of the signer is constant, the verifier costs is also constant, the CRL size is inevitably rising but it is minimize and the CRL issuance cost is also unavoidable, however it is the least significant (Ateniese et al, n. d. ). The revocation method with the ACJT group signature scheme had been proven to be efficient and secured. This more practical than other group signature due to its features that fixes the size of the signature and requires constant work by signers. However, the ACJT group signature scheme requires the use of proofs-of-knowledge involving a double discrete logarithm (Ateniese et al, n. d. ). Conclusion These articles had proposed changes to other group signature schemes and some presented their own schemes. Generally, these articles aim to the advancement of the concept of group signature in relation to efficiency. The articles above had proposed methods of how to satisfy six properties needed fro a secure group signature scheme. These schemes are still subjected to further research to optimize its efficiency without compromising its security. References Ateniese, G. , Camenisch, J. , Joye, M. , and Tsudik, G. (2000). A practical and provably secure coalition-resistant group signature scheme. Advances in cryptography, CRYPTO, 1880, 255-270. Ateniese, G. , Song, D. , and Tsudik, G. (n. d. ). Quasi-efficient revocation of group signatures. The Johns Hopkins University University of California. Popescu, C. (2002). An efficient ID-based group signature scheme. StudiaUniv. Babes-Bolyai, Informatica, 47, 29-35. Popescu,C. , Noje,D. , Bede, B. and Mang, Ioan. (2003). A group signature scheme with revocation. University of Oradea. (Popescu et al. , 2003) Wang, G. , Bao, F. , Zhou, J. , and Deng, R. H. (n. d. ). Security remarks on a group signature scheme with member deletion. Infocomm Security Department, Institute for Infocomm Research.

Gods Word in Schools Essay Example for Free

Gods Word in Schools Essay Currently our country is in moral decay because we are not raising our children under the authority of Gods Word. For example, some parents feel as though their children should not have to do chores around the house. It is our responsibility as parents to educate our children on what Gods Word  says about all of lifes issues, including chores. In Jane Smileys, The Case Against Chores she attacks parents that have their kids do chores saying that it alienates children from the family, but it my family it brings us together because we all pitch in to get the job done. In 1 Samuel 16:11 it says when Samuel came to anoint David, he was in the field tending the sheep. He was doing his chores! This passage clearly indicates that God wants kids to do chores. Whether or not our kids do chores is not the biggest issue though. In the 1960s the U. S. Supreme Court decided to take prayer out of our schools. From that point on our country has seen a vast moral decay resulting in things such as AIDS and the murder of millions of innocent babies. Are we to blame the government for this? How about the school system? We need to look at ourselves as parents. Since our school systems are not going to allow the Word to be taught we parents must take up the sword and teach our children what God has to say about lifes major issues. Traditional family values are quickly becoming a thing of the past. In her article Ms. Smiley states, And dont the parents love their children anyway, whether the children vacuum or not? This is insinuating that the only reason parent’s love their kids, is because of the work they do. To that I say its because we love our kids we assign them chores. This helps them learn responsibility. The Bible says, Train up a child in the way he should go: and when he is old, he will not depart from it (Proverbs 22:6). Its not just about teaching our children what the Word says, but we must show them in our relationship with them. Ms. Smiley says in her article when she was taking care of her horse she saw the purpose of her labor. If we educate our children about Gods Word they will see the purpose in everything they do. Colossians 3:23 says, And whatever you do work at it with all your heart, as working for the Lord, not for men. When Gods Word is in our heart our entire life takes on new meaning. Ms. Smiley says in her article when she was a girl she had a problem with a teacher because she (Ms. Smiley) always did what she wanted to do. She had no responsibility. She would leave for school with her room a mess and return home and it would be cleaned up for her. Its clear that Gods Word had not been taught to Ms. Smiley. The Bible says in Romans 13:1 that we are to submit ourselves to authority. Proverbs 15:33 tells us the fear of the LORD teaches a man wisdom. Had Ms. Smiley been taught the Word there would not have been a problem. In the case of Ms. Smiley we can see where our culture is going astray. We have gotten away from God in the home and in the schools and we now have one generation passing down their values (or lack thereof)  to another. In order to restore our country to what our founding fathers intended it to be we must start in the homes. We can do this by giving our kids chores, disciplining them when needed, telling them what they need to hear as opposed to what they want to hear, spending time with them, showing them love, and most importantly teaching them about our Heavenly Father. In doing so we can bring up a nation of young leaders who can restore this great land to what it once was, one nation under God with liberty and justice for all.

An Overview Of A Constructions Productivity Construction Essay

An Overview Of A Constructions Productivity Construction Essay Recently, construction productivity is on a long-term slide and it is recognized as industry challenge. System, people, materials, information and energy must flow effectively and efficiently to produce its objective at high productivity to complete construction at lowest possible cost with possible shortest timeframe (Picard, 2005). Productivity is critically important in construction industry. Many researchers have expressed their concern over productivity in construction industry. Defining productivity is not a simple task to everybody. Different people will give different definition and understanding. Most of them agreed that marketable output was essentially the main measure used. Increased productivity was a leading concern to all Committee stakeholders such as users, contractors, and construction labor unions and led by the owner. The construction users emphasized the need of collecting data directly relevant to productivity improvement. The Committee was concluded that the front-line construction foreman/supervisor would be a reliable source of information. These informants would be asked to provide their judgment of the greatest impediments to a productive construction project (Tucker, 2003). Definition of productivity Within these several decades, many researchers have defined the productivity term in their studies in a number of ways. The term productivity has different meanings to different people. Many individuals automatically think only of labor unions when the term productivity is mentioned. Others associate capital expenditures with the term. Each of these interpretations is only partly correct (Adrian, 1993). Many researchers have attempted to define precisely the meaning of productivity and below are some of it that referred from their studies: Oglesby et al. (1989), presented that productivity can be defined as in-place value divided by inputs . Some researchers have defined it as works-hours divided by the equivalent quantity of work. In construction, productivity normally can be understood as work quantity divided by man-hours (or work-hours) consumed to accomplish the work. Productivity = Work Quantity Man-hours According to Dolman, Parham, Zheng, (2007), productivity is a measure in order to know how much output is produced per unit of input. Diewert Lawrence, (2006) presented that productivity can be defined as the level of economic output per unit of input and also per worker. Productivity is important to the wealth and well-being of a nation and give efforts to improve productivity occur at all levels of society. According to Hwang and Liu, (2005), productivity is an effective index that can indicate output of construction work quantity versus the input of resources. Productivity of a crew is directly impacts the cost and time needed to complete a task. By analyzing and forecasting productivity, project manager can be more effective to control and predict project time and cost throughout execution up to completion. Thomas and Mathew, (1986) presented that no standardized productivity definition had been established in the construction industry. It is difficult to define a standard productivity measure because companies use their own systems which are not standardized. Association simply illustrates the productivity between an output and an input. The form has been widely used and existing in literature over the years in construction industry is; Productivity = Input/Output Prokopenko, (1987), defined the productivity as effective and efficient utilization of all resources, labor, plant and materials. According to Jugdev, et al.,(2001), productivity is a ratio between inputs and outputs. In calculating the productivity, it is important to specify the inputs and outputs that to be measured because there are many inputs such as labors, materials, equipments, tools, capital and design in construction system. Uusi-Rauva and Hannula, (1996), presented that productivity can be defined as internal efficiency of the organization or other object to be measured. A more precise definition of productivity is the following: output divide by the input that is used to generate output. Output is consists of products or services and input is consists of materials, labor, capital, energy, etc. Productivity is not only affected by the quantities of inputs and outputs but also the qualities of inputs and outputs. According to Halligan, et al., (1994), there are many ways to define productivity. In construction, it is usually taken to mean labor productivity which is units of work placed or produced per man-hour. Teicholz, (2004), stated that productivity in construction industry was measured by constant contract dollars of new construction work per hourly work hour The Bureau of Labor Statistics (BLS, 2009) of the U.S. Department of Labor was defines productivity into two type which are labor productivity and multifactor productivity. Labor productivity can be measures as output per hour of labor and it is used in over 40 industries including construction. Productivity can be calculated by dividing the quantity of work completed (Quantity) by number of labor hours used to complete the work (Man Hours). A productivity value represents performance of an operation with respect to time and cost, where activity duration and activity cost is directly affected by productivity. Duration (Hours) = Quantity of Works (Quantity / Man Hours) = Quantity of Works Productivity The formula above indicates how critical the reliability of the productivity factors in estimation time. Measurement of productivity There is controversy surrounding productivity that rooted in the differences in data collection. It is due to incorrect in assuming productivity measured uniformly and that all published productivity values have the same basis (Whiteside, 2006) Overall conception of productivity is difficult to express or to measure. It is sometimes expressed either in terms of output from labor or from services or from capital invested. These parts of expressions often do not give an accurate picture of the overall position. Although, there are measurements of some or all of the inputs and outputs of the industry but they still failed to combine these measurements into any satisfactory measure of efficiency. In fact, the ratio is easy to compute if the unit uses a single input to produce a single output (Choy, 2008). According to Whiteside, (2006), production is average direct labor hours to install a unit material. He also stressed that in perfect world, perfect productivity (1.0) will be accomplished in 40-hour work week, with everyone taking all of their holidays and vacation days planned. It is regarding to all the engineering drawings must be 100% complete, there would be no delays of any kind, everyone would work safely, everything would fit perfectly at the first time, the weather would be 70 degrees Fahrenheit and there would be no litigation at the end of the project. But, we do not live in perfect world and true productivity is often poorly understood. The first challenge in understanding productivity is lacking of common terms. The definition of hours identified as direct labor should be consistent. Second is too much focus in determining productivity which is incorrectly placed on the individual worker. Productivity is something to do with the worker because many workers work at the s ame rates. The main thing should be focused in productivity measurement is proper or complete planning. It is because like-out-sequence work will contribute to lower productivity due to the rework hours required to complete the original task. The final challenge is how to make productivity comparison when the data used in productivity studies before have the same basis. Productivity is not based on wage rates or cost data alone and it is improper to combine wage rate, hours and material quantities to make productivity comparison. According to Hwang and Liu, (2009), construction productivity studies have centered on the identification of factors that influence productivity and quantification of the impact of such factor on productivity. As a result, there were various qualitative and quantitative factors have been discovered and various methods for productivity have been presented. Majority of those methods are based on relationships between productivity and factors. Based on Thomas and Yiakoumis (1987), they stated that theory underlying the factor model is the work of crew is affected by a number of factors. If the cumulative effect of these disturbances can be mathematically represented, then the expected actual productivity can be estimate. But, it is not always feasible to quantify the impact of various factors and represent the relationships mathematically. Another limitation is the value of many related factors in future is not available and thus, they have to be estimated. In fact, some of the factors can be correlated with others which the correlation may be higher or lower under different situations. There is several research efforts have been devoted to developing models. The models that being used in the construction industry are such as below: According to Sonmez and Rowings, (1998); Portas and AbouRizk, (1997), recommended Neutral Network (NN) techniques which have been used to develop method of productivity prediction. Everett and Farghal, (1994), recommended learning curves that for various activities. Abdelhamid and Everett, (1999), have applied time series analysis to evaluate hoisting performance comparing the CRANIUM technology with the conventional technique. According to Brockwell and Davis, (2002), ARMA (autoregressive moving average) models are used to model time-lagged relationship of self-correlated observations within a single series. Cumulative Average and Simple Moving Average that wisely used to model a single time series Exponential Smoothing produce forecasts of weighted value of past observation with exponentially decreasing weights (NIST, 2006). Although there are numbers of publications exist on construction productivity, there is no agreed upon definition of work activities nor a standard productivity measurement system. Most of researchers have concluded that it is difficult to obtain a standard method to measure construction labor productivity because of project complexity and unique characteristics of the construction projects (Oglesby et al. 1989). The uniqueness and non repetitive of operation in construction projects make it is difficult to develop a standard productivity definition and measure (Sweis, 2000). Current measurement of productivity in construction industry Our labor productivity experts specialize in labor productivity analysis and may utilize the following industry-recognized methodologies, where appropriate: Measured Mile Analysis Work Sampling Comparable Work Study General and Specialty Industry Studies (Mechanical Contractors Association of America [MCAA],  Construction Industry Institute [CII], Business Roundtable, etc.) Total Cost Method Modified Total Cost Method Time and Motion Studies   The selection of a particular productivity analysis methodology is depends on the project facts, the nature of the events being analyzed, the nature and extent of available labor data and may vary from project to project. Each of the above-referenced productivity analysis methodologies has inherent its own advantages and disadvantages. Interface Consulting has extensive experience handling construction labor productivity claims and construction claims consultants are skilled at tailoring productivity analysis approach to suit a projects needs and constraints (ICII, 2009). Factors influence productivity in construction According to Tucker, (2003), he presented the most factors that can affect the construction productivity especially on site as below: Design: specifications, drawings, documents have to be improved Field support for timely responses; have architect/engineer on site with field competency Coordinate Design/Review Timely RFIs/RFPs (Request For Informations/Request For Proposals) Construction/Project management competency He also suggested that productivity improvement should be done based on this area: Constructability of the design documents with input of major contractors on schedule quality and realism Coordination among major contractors Pre-project planning Communication and teamwork between owners, design professionals, contractors and labor Improvement of the construction management process. Parisi, (2008) presented that potential factors influence the construction productivity are many, including out-of-sequence work; skilled labor shortages; worker crowding/congested work areas; interference of trades; owner interference; design problems and defects; contractors inadequate management/supervision; failure to properly staff the project; overtime; and acceleration. Lim et al (1995) studied factors affecting productivity in the construction industry in Singapore. Their findings indicated that the most important problems affecting productivity were: difficulty with recruitment of supervisors; difficulty with recruitment of workers; high rate of labour turnover; absenteeism from the work site; and communication problems with foreign workers. Olomolaiye et al (1996) studied factors affecting productivity of craftsmen in Indonesia, with their findings indicating craftsmen in Indonesia spent 75 % of their time working productively. Five specific productivity problems were identified: ie lack of materials; rework; absenteeism; lack of equipment; and tools. Kane et al (cited in Herbsman et al, 1990) classified factors affecting construction productivity into two main groups: technological factors and administrative factors. The technological factors encompass those related mostly to the design of the project; the administrative group factors relate to the management and construction of the project. Technological factors comprise sub-groups such as design factors, material factors and location factors. Administrative factors comprise sub-groups, such as construction methods and procedural factors, equipment factors, labour factors, and social factors. Heizer and Render (1990) classified factors influencing site productivity into 3 groups: labour characteristic factors; project work conditions factors; and nonproductive activities. Olomolaiye et al (1998) stated that factors affecting construction productivity are rarely constant, and may vary from country to country, from project to project, and even within the same project, depending on circumstances. They classified factors influencing construction productivity into 2 categories: external and internal, representing those outside the control of the firm s management, and those originating within the firm.. External factors included the nature of the industry, construction client knowledge of construction procedure, weather, and level of economic development. Internal factors included management, technology, labour, and labour unions. Enshassi et al 2006, Enshassi et al 2007, and Al Haddad 2007 stated that among the problems which the Palestinian construction industry is facing are material supply schedules and project scheduling techniques. Although a number of training courses were conducted to local contractors, these training efforts did not focus enough on the abilities to use project scheduling techniques such as Microsoft project and Primavera. Therefore training effort should also be tailored to improve methods of studying productivity and ways of productivity improvement on construction sites. The important productivity rate in project scheduling The duration of construction project is a key factor to consider before starting a new project which is it can be determine project success of failure. Despite the uncertainty and risk level is very high in construction industry, current construction planning which is more relies on traditional deterministic scheduling method is still not clearly ascertain the level of uncertainty involved in the project. Subsequently, it can prolong a projects duration and cannot be completed within the allocation time of the project (Lee, et al., 2009). Construction projects are subjected to changes which it require constant performance monitoring and follow-up schedule updates. Project manager must take proactive attitude to analyze project data and to predict potential problems and delay in order to make timely decisions and to reduce the negative impact on cost and schedule (Hwang and Liu, 2005). Planning in construction is a complex and iterative process. A plan usually is prepared based on the estimates by the participants actual commitment. Therefore, construction productivity plan plays a significant role in the process. Based on Parisi, (2008), in estimating labor, there are several key factors that should be considered: Productivity of its field forces Union labor agreements and requirements Past experience with the owner, designer, and construction manager Labor availability Specialty trades Therefore, if the actual construction work deviates from the anticipated plan, once the contract is signed and the project is underway, several situations may result as below: The job may take more time because the progress is not being made at the rate projected in the original baseline schedule and thus, project completion must be extended. (In such cases, acceleration of the remaining activities may be implemented to recover time) More hours of labor may be required to install the work items because materials are not being installed by the contractors workforce at the productivity rates (the anticipated quantities of material to be installed per hour) same as estimated in the original bid. An overrun of both time and labor may occur. In order to succeed, the companies must make a phase affirmative action into the total management of productivity through a formalized, documented process such as depicted in Figure 2.0. The process should be started with historical productivity analysis. The knowledge that gained from this processes should then be utilized to forecast and manage future productivity. The supervisor that involved in this process must implement and monitor the predetermined productivity values. Only then the companies can be more competitive and successful in todays global market Figure 2.0: A model to manage construction productivity Construction industry seemed as low sector when there is low technology and low skilled employments occur. According to Saad, (2002), in order to raise level of construction productivity, it is recommended that the projects should have the following features: High degree of standardization Design is preferred to use pre-fabricated units or pre-assemble forming system Building system should be easy and simple to construct and repetitive Well managed construction methods with details planning and specification High level of mechanized methods and skilled workers Roof works Roof is a basic human need is for shelter, which for most of us consists of a few walls and a roof over our heads. Roofs come in many shapes and sizes. One of the main reasons for having a roof is to keep out rainwater and snow. The selection of roof is based on the following characteristics: Stability Protection from the sun, weather, wind and rain Durablity Heat resistance Brightness and ventilation Beauty Construction of roof must be strong and able to support the load and stressed that going to happen. The load that is attributable to roof, firstly is dead load which is the weight of the roof trusses, roof covering; secondly is live load which is consists of tools, equipment, workers, rain water and lastly is wind load. Wind is a major stress to the roof which is difficult to forecast accurately. Roof stability is depends on the support such as roof trusses, column, walls, beams and foundation of the building. Design of roof also takes into account the respective functions of the building. Building for residential and office should have a comfortable situation in terms of condition, light, air and dam parts sounds. Industrial buildings and warehouses may require heat insulation on the roof to maintain the same conditioning in buildings. Traffic in the building to allow use of the pillars supporting the roof of the short-range distance. Roof for theater and stadium, must be supported by long span of roof trusses and the support in the middle will distrupt the view and noise and sound effect protection from the audience. Productivity work to be consider in roof works The productivity works to be considered in this study as below: Installation of roof trusses (cold form) Installation of insulation Installation of roof covering (concrete roof tiles and metal decking) No. of workers in group Daily Productivity (m2) METHOD PRODUCTIVITY OF ONE WORKING DAY Handling Half Mechanized Full Mechanized Summary From the literature review of the productivity in construction is important especially to provide accurate duration of task in building project scheduling. Rerefences: Dolman, B., Parham, D., Zheng, S. (2007), Can Australia match US productivity performance?, Retrieved May 7, 2007, from http://www.pc.gov.au/commission/work/productivity/publications/reports.html. Diewert, W. E. and Lawrence, D. (2006), Measuring the contributions of productivity and terms of trade to Australias economic welfare, Retrieved May 7, 2007, from http://www.pc.gov.au/commission/work/productivity/publications/reports.html. Oglesby, C.H., Parker, H.W. and Howell, G.A., (1989), Construction productivity improvements, McGraw Hill, New York Adrian, J.J. (1993), Construction Estimating: An accounting and productivity approach 4th Edition, 1993 Hwang, S. and Liu, L.Y. (2005), Proactive project control using productivity data and time series analysis, Computing in Civil Engineering 2005 Thomas, H.R. and Mathew, C.T., (1986), An analysis of the methods for measuring construction productivity, SD 13, Construction Industry Institute, The University of Texas. Whiteside, J.D., (2006), Construction Productivity, AACE International Transaction, 2006 Picard, (2005), Construction productivity qualifications, Cincinnati, Ohio, USA Prokopenko, J.,(1987), Productivity management, Geneva International Labor Office. Jugdev, K., Thomas, J. and Delisle, C., (2001), Rethinking project management old truths and new insight, International Project Management Journal, 7(1), pp. 36-43 Uusi-Rauva, E. and Hannula, M., (1996), Measurement A tool for productivity Improvement, 9th International Working Seminar on Production Economics, Innsbruck, pp. 13-29 Halligan, D.W., Demsetz, L.A., Brown, J.D. and Pace, C.B., (1994), Action-response model and loss of productivity in construction, Journal of Construction Engineering and Management, Vol. 120 No. 1, March 1994 Teicholz, P., (2004), Labor productivity declines in the construction industry: Causes and remedies, AECbytes Viewpoint #4, April 14 2004. Tucker, W.W., (2003), Construction Productivity Study Summary, Eastern Michigan University, 2003. Choy, C.F., (2008), Productive efficiency of Malaysian construction sector, Built-Environment Department, Faculty of Engineering and Science, University Tunku Abdul Rahman, Malaysia. Lee, H.S., Shin, J.W., Park, M. and Ryu, H.G, (2009), Probabilistic duration estimation model for high-rise structural work, Journal of Construction Engineering and Management, December, 2009 Hwang, S. and Liu, L.Y. (2009), Predicting short term productivity I: Contemporaneous time series and forecasting Methodologies, Journal of Construction Engineering and Management, December, 2009 Sonmez, R. and Rowing, J.E., (1998), Construction labor productivity modeling with neutral network, Journal of Construction Engineering and Management, December, 124(6), 498-504 Portas, J. and AbouRizk, S. (1997), Neutral network model estimating construction productivity, Journal of Construction Engineering and Management, 123(4), 399-410 Everett, J.G. and Fargahl, S. (1994), Learning curve predictors for construction field operations, Journal of Construction Engineering and Management, 120(3), 603-614 Abdelhamid, T.S. and Everett, J.G., (1999), Time series analysis for construction productivity experiments, Journal of Construction Engineering and Management, 125(2), 87-95 NIST, (2006), Engineer statistic handbook Oglesby, C.H., Parker, H.W., and Howell, G.A., (1989), Productivity improvement in construction, McGraw-Hill, New York. Sweis, G.J., (2000), Impact of conversion technology on productivity in masonry construction, PhD dissertation, Northwestern University, Evanston, III. Interface Consulting International, Inc.(ICII), 2009 Parisi, R.F., (2008), When the best-laid plans go astray A primer on labor productivity, Capital Project Management, Inc. Saad, D.A, (2002), Standard labor productivity of reinforced concrete building structures and factor affecting on it, Thesis presented to university of Technology, Iraq FACTORS AFFECTING LABOUR PRODUCTIVITY IN BUILDING PROJECTS IN THE GAZA STRIP Adnan Enshassi1, Sherif Mohamed2, Ziad Abu Mustafa1 and Peter Eduard Mayer3

Internet Security Essay -- essays research papers

Security on the Internet How do you secure something that is changing faster than you can fix it? The Internet has had security problems since its earliest days as a pure research project. Today, after several years and orders of magnitude of growth, is still has security problems. It is being used for a purpose for which it was never intended: commerce. It is somewhat ironic that the early Internet was design as a prototype for a high-availability command and control network that could resist outages resulting from enemy actions, yet it cannot resist college undergraduates. The problem is that the attackers are on, and make up apart of, the network they are attacking. Designing a system that is capable of resisting attack from within, while still growing and evolving at a breakneck pace, is probably impossible. Deep infrastructure changes are needed, and once you have achieved a certain amount of size, the sheer inertia of the installed base may make it impossible to apply fixes. The challenges for the security industry are growing. With the electronic commerce spreading over the Internet, there are issues such as nonrepudiation to be solved. Financial institutions will have both technical concerns, such as the security of a credit card number or banking information, and legal concerns for holding individuals responsible for their actions such as their purchases or sales over the Internet. Issuance and management of encryption keys for millions of users will pose a new type of challenge. While some technologies have been developed, only an industry-wide effort and cooperation can minimize risks and ensure privacy for users, data confidentiality for the financial institutions, and nonrepudiation for electronic commerce. With the continuing growth in linking individuals and businesses over the Internet, some social issues are starting to surface. The society may take time in adapting to the new concept of transacting business over the Internet. Consumers may take time to trust the network and accept it as a substitute for transacting business in person. Another class of concerns relates to restricting access over the Internet. Preventing distribution of pornography and other objectionable material over the Internet has already been in the news. We can expect new social hurdles over time and hope the great benefits of the Internet will continue to ove... ...o that its confidentiality and integrity are preserved. That is, the data remains secret to those who do not posses the secret key, and modifications to the cipher text can be detected during decryption. Two of the most popular symmetric ciphers are the Data Encryption Standard (DES) and the International Data Encryption Algorithm (IDEA). The DES algorithm operates on blocks of 64 bits at a time using a key length of 56 bits. The 64 bits are permuted according to the value of the key, and so encryption with two keys that differently in one bit produces two completely different cipher texts. The most popular mode of DES is called Cipher Block Chaining (CBC) mode, where output from previous block are mixed with the plaintext of each block. The first block is mixed with the plaintext of each block. The block uses a special value called the Initialization Vector. Despite its size and rapid growth, the Web is still in its infancy. So is the software industry. We are just beginning to learn how to develop secure software, and we are beginning to understand that for our future, if it is to be online, we need to incorporate security into the basic underpinnings of everything we develop.