...A Distributed Transaction Management Scheme for Multidatabase Systems* Xinfeng Ye, Department of Computer Science, University of Auckland, New Zealand. Abstract finsaction management in a multidatabase sys- tem must ensure global serializability. Local seri- alizable execution is, by itself, not suficient to en- sum global serializability, since local serialisation or- ders of subtmnsactions of global transactions must be the same at all systems. In this paper a distributed tmnsaction management scheme is introduced. The scheme maintains autonomy of the local database systems. It is free from global deadlock, and, guar- antees fairness in the execution of the tmnsactions in the system. 1 Introduction A multidatabase system (MDBS) is a collection of pre-existing autonomous, and possibly heteroge- neous, local database systems (LDBSs). Transac- tions in an MDBS are of two types: Local transactions: Those transactions that only access data m,anaged by a single LDBS. Global transactions: Those transactions that ac- cess data managed by more than one LDBS. Transaction management in the MDBS is hierar- chical. Each LDBS controls the local transactions and the subtransactions of the global transactions at its site, and assures serializable execution at that site. The MDBS software controls the global trans- actions, and assures global serializability. Global serializability guarantees the correct con- current execution...
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...The Deadlock Problem Law passed by the Kansas Legislature in early 20th century: “When two trains approach each other at a crossing, both shall come to a full stop and neither shall start upon again until the other has gone.” Neil Groundwater has the following to say about working with Unix at Bell Labs in 1972: ... the terminals on the development machine were in a common room ... when one wanted to use the line printer. There was no spooling or lockout. pr myfile > /dev/lp was how you sent your listing to the printer. If two users sent output to the printer at the same time, their outputs were interspersed. Whoever shouted. “line printer!” first owned the queue. 1 Deadlock or Deadly Embrace Permanent blocking of a set of processes that either compete for system resources or communicate with each other – Several processes may compete for a finite set of resources – Processes request resources and if a resource is not available, enter a wait state – Requested resources may be held by other waiting processes – Require divine intervention to get out of this problem A significant problem in real systems, because there is no efficient solution in the general case Deadlock problem is more important because of increasing use of multiprocessing systems (like real-time, life support, vehicle monitoring, multicore utilization, grid processing) Important in answering the question about the completion of a process Deadlocks can occur with – Serially reusable...
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...Weakness KFF has managers but managers have many responsibilities. Kathy takes on most of responsibilities at the stores. She does the ordering for all stores, inventory, and financial records. She drives to and from each store daily to do this work. Even though she has management team she does all the work. I feel she should train managers to do their jobs function the way that she does them to ensure someone is always there to run the stores. It is not good for her to do all functions of the store and not let managers do their job. Kathy should think long term. If she was to get sick and have to b off for a week or more, who will know how to run the store with it’s many operations. If no one knows the operations of the store and she is sick the store will have some problems. There would be no one to order inventory, do the business statements, and help rotate out bad foods. Kathy needs to train others to do her job so that everyone knows the job if someone had to be off and next person had to do their job along with missing person duties. I think Kathy is so use to doing everything for the stores it is hard for her to entrust her store with anyone. It seems like she does not trust others to do good job like she has done. Kathy needs to let some upper level managers come in her store or and train teach everyone how to do their job as she expects them to be done. She...
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...Case 1: Heart Attack Managing People and Ethics 3/25/2011 Management 301- Business Organization and Management Eboni Thrower, Jennifer Jackson, Gerald Grant III, Taneisha Pryor Dr. Makamson 1.___________________________ 2.___________________________ 3.____________________________ 4.____________________________ I. Problem Statement Was Mr. Hamid wrong for firing Shauna? Mr. Hamid placed an ad for a part-time bookkeeper at a local college and Shauna came across it. The work Mr. Hamid needed finished for his company would only require the bookkeeper to stay in work with him for about two months. She applied for the job and received the job the same day. During the interview Mr. Hamid stated that he would pay her $150 per week. Realizing that if she accepted $150 per week she would not be making as much money as she would if she worked on an hourly rate; she had to come up with a plan. Shauna negotiated with Mr. Hamid and agreed to work Monday, Wednesday and Friday for seven hours a day for 21 hours a week at $10 per hour. In this agreement Shauna would be put on a three month probationary period, which consisted of no time off, vacation, sick days or holidays off. Shauna was a hard worker and an excellent bookkeeper for Mr. Hamid. She always completed every project and obligation that was ever asked of her beforehand. Shauna constantly asked Mr. Hamid for extra work to do in the office to keep her busy. She never took any time off from work, nor did she ever...
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...occurred? | My co-worker thought that I was trying to take over as the representative of his student. | How could the misunderstanding have been avoided? | The misunderstanding could have been avoided if the co-worker would have called me back before going to his supervisor. | In this situation, I was the one who made the first mistake; that being that I didn’t put my notes into our database when my student referred her husband as a possible student. My student’s husband then called the next day and spoke with my co-worker, Michael, who took all of his information and enrolled him. I received a phone call from my student the next asking why I had told her one thing and Michael had told her husband another. With Michael being new to the job, I thought he made a simple mistake, so I called and left him a voicemail suggesting that we talk about the students to make sure that we were on the same page in what we were telling our students. I then wrote my supervisor an email telling him what I did and said. Michael, upon hearing the message, went to his supervisor because he had the impression that I was trying to take his student from him. His supervisor went to mine asking what was going on. My supervisor explained everything and the matter was resolved. As a result, both the students did not complete the enrollment process or start school. The main thing I learned from this whole ordeal was to make sure that all of my notes are complete and to make sure...
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...benefits of tuition reimbursement to student-employees. She states that these companies help a student with their school costs as well as money in pocket. As well as filling your pockets the author explains how building a solid resume while in college is also important. Ramachandran sums up her article with explaining how important your schoolwork can be. She states some helpful tips; do not expect to pay off college while still in college. The author brings everything into perspective by explaining that students that work 10 hours a week on average have a much better GPA than those students that work 25 or more hours. With dealing with the financial stress of college jobs are not always the answer. Financial aid advisors can help you get money that you won’t have to pay off until later. “After all, the primary job for those in college is to be a...
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...director. The participant group was asked to self-report on perceptions of role ambiguity, experienced levels of anger, anxiety and workplace threat appraisal. In this study, participants were asked questions as to whether they fully understood what was expected of them at work on a day-to-day basis regarding particular tasks, or a range of tasks. This data was then compared with responses to questions which probed whether they had felt anxious or angry at work. Threat appraisal was determined by whether the respondent felt it was more or less likely that their work day was going to be a negative experience for them. Dr Searle’s study found statistically significant correlations between a lack of clarity an individual has regarding their job requirements and reported feelings of anger, anxiety and their threat appraisal. These findings reinforce earlier research conducted by Robert Pearsall from the University of Maryland which demonstrated that these increases in anxiety, anger and threat appraisal can...
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...many organizations implementing the same. It provides flexibility to work part-time and work from home, which is a critical issue for many working females particularly and also among the male members where they can manage their family and work life very well. It provides a heightened sense of loyalty to the employees because they know that their boss trusts them to do their job sincerely, which in turn increases their pride and responsibility towards their work. It has been witnessed that productivity improves when the focus on work improves. It allows people to develop a better understanding of their job and eliminate office space time-wasters like "fake meetings" etc. ROWE also eliminates the illusion of productivity created by the "come early, leave late" mentality many firms require for promotion. Thus the focus is primarily towards results instead of punching the time clock or logging desk time. 2. Identify factors in the ROWE program that might make using it for retail employees more difficult than using it for managers and employees in corporate offices, technical centers, and nonretail jobs and locations. The ROWE-type program has been implemented by various organizations across a broad spectrum in different departments such as IT, back office, etc. But at places like retail stores or bank branches, where one to one customer interaction and service...
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...environment may cause can be detrimental to a person’s health. When anyone| | |is stressed, it can create a number of problems with their health. | |Identify a situation in which you experienced stress in the workplace or provide a |Fictional example: I had been scheduled to work 4 late shifts, out of 5 working days. Every other | |fictional example. |employee only had to work 1 late shift. I brought it to her attention and explained that it was not part| | |of the job requirements when I was hired on. She was visibly upset that I had brought it up and did not | | |want to discuss it at all. Instead, she changed the schedule and made it unbearably tense for the | |...
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...website. The matter of stress is serious and is an ongoing concern. As indicated by both articles that the tough economic times that lead to significant changes within the workplace, has contributed to the increased in stress factors among workers and greatly affect businesses. One major stress factor stemmed from the economic crisis is uncertainty or the fear for the lost of job. The American Psychological Association explains that bankruptcies are among the list of things that caused hundreds of thousands of workers their jobs. Additionally, while millions more have been shifted to unfamiliar tasks within their companies, this dramatic shifting has caused many to wonder how much longer they will be employed. Holmes-Rahe Life Events Scale, in the PDU Magazine Article, also pointed out that many of the most stressful events are related to the workplace and in addition to the lost of job, “firings” on the list mentioned, is the changes in financial status. Undoubtedly, being put out of a job has alarming effects on the individual. According to the American Psychological Association, “the loss of a job can be devastating, putting unemployed workers at risk for physical illness, marital strain, anxiety, depression and even suicide”. In the same light, the PDU Magazine Article has listed the same effects and more, but looked at these effects as a “heavy price” since they take a toll on the individual not only physically but psychologically. Employers and employees within various...
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...Effective Communication will help with better understanding of each other, and have a broader perspective. With effective communication bring more confidence, admiration, and a better work environment where we as people would be able to excel within the work place, having more creative thoughts, being able to problem solve more complex situations. Effective communication is good to have so that both parties will be able to convey the message in which each will understand. It will also help with everyday life setting whether it be dealing with work related relationships , or personal life. I have a experience a few times where I was to use effective communication in the workplace. One time I can recall, were there had been a discrepancy between a co-worker and I that was work related . I work for a Bank, within their retail card service department, lending for private label credit cards where I have to make decisions for financing based on a clients credit ratings, and my co-worker and I had a issue pertaining to lending of credit to the client. A few weeks had went pass where my co-worker and I had not spoken to each; although we were both on the same team, we had no form of communication towards each other, we were both stubborn when it came to issue at hand and wasn't backing down to each other opinions. It soon became a problem where it was becoming noticeable in the work place, and affecting my quality of work. Not only was the discrepancy affecting me and work-related...
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...limitations in the workplace, but older employees have more limitations than the younger workers. Many studies have been conducted on age and work performance, and there were no difference in older workers and younger workers performance. They both have positive and negative effects in the workplace, but there no research that will make the claim that one age group performance is better than the other (Warr, 1993). However, most people think that older workers are more stability, experience, productivity, and this is commonly not originate in younger workers. They believe with all the good work ethic that older employees have they should do well in the workplace. There has been a study that shows that older workers are more faithful to their job, more realistic and more responsible about their standing in a business, as contrasted to younger employees. Both younger and older employees have their advantages and disadvantages in the workforce. Both groups have some decline in the workplace, and it will be difficult to say which...
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...When thinking about transformational changes, many don’t know that if can be something that has happened to them in the past or even present. Transformational changes can be anything from recognizing a significant problem such as not being able to get promoted in a job that you are working for. When thinking about confronting it intensely can be you thinking of reasons on why you’re not getting promoted such as education wise. When finding the solution it could be to get back into school to earn a degree so that when a promotion comes up you are on top of your game and know what to expect. Integrating a new perspective and a new set of assumptions into your life pattern was to take the knowledge that the person has learned as used it in their career. Many people may take the transformational changes to make themselves better but to also make their job more of a career then something that they have to do on an everyday base to base. A transformational change that I did to myself was when working in a child care setting it is hard to want to move up the line to better yourself as a coworker. I had recognized a significant problem about my career and that was the promotion part. Being in the child care setting and working on post for the military they would like to have their co-\workers to have some sort of degree when working in that kind of setting. That was the confronting the intensely part was knowing that I didn’t have a degree. So what I wanted to do was to better myself...
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...Are tattoos appropriate in the workplace? Tattoos may or may not be appropriated in the workplace, because depending on what or where the tattoo located, there may or may not be an issue for the employers. It depends also on the employers industry and the type of job. Employees should be aware of the issues and the policy that prohibit tattoos. More and more employees are getting tattoos whether they are invisible or visible. There are some workplace can get exposed to a liability if the presence of the tattoo was an issue in making the hiring decision. The key for employers to have written policy that employees should be required to read and sign, about "no visible tattoos." Employers are reluctant to hire those with visible tattoos. Because, some tattoos are distracting, and it very unprofessional. Some people look at your tattoos and judges your appearance and stereotype you. I know applying for a job, you shouldn't have invisible tattoo, and because they might assume that the tattoo have a bad meaning. There shouldn't be any revealing tattoos during interviews. According to an article by Jennifer D. Melville even though tattoos are not allowed in the workplace, you can still have them just more in an unraveling setting. In a professional business setting, tattoos are unacceptable and should not be seen at all. I believe that tattoos do have a meaning when trying to get in a workplace, some peoples that have tattoos whether...
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...what you can potentially produce. If you cannot show that you can produce results you have no place in the workplace. So, in whatever capacity you are working in begin to measure your results and outcomes, and start documenting your accomplishments. Most people assume that accomplishments need to be large. No. Very rarely do people have significant accomplishments, but there are many milestones (and occasional breakthroughs) that happen in one’s work life. So, ask yourself these simple questions: 1) What have I accomplished (done) in the past 2 years that made a difference in the workplace? Have I received recognition or promotion or appreciations from colleagues, customers, managers or others? 2) Have I done anything outside my job description? 3) Am I replaceable? Why not? What unique value do I bring to the workplace? Why should the company continue to pay me? 4) What are top three areas that I have improved significantly in the past 3 years? Will these help me scale to higher levels of performance and responsibilities? 5) What have I done in the recent past that makes me deserving of a promotion or greater...
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