Data and measurement problems have complicated the debate over trends in job instability in the United States. In this paper we compare two cohorts of young white men from the National Longitudinal Surveys (NLS), construct a rigorous measure of job change, and confirm earlier findings of a significant increase in job instability in recent years. Further validation of this increase is found when...

We examine scheduling problems where we control not only the assignment of jobs to machines, but also the time used by the job on the machine. For instance, many tooling machines allow control of the speed at which a job is run. Increasing the speed incurs costs due to machine wear but also increases throughput. We discuss some fundamental scheduling problems in this environment and give algori...

the aim of this cross sectional study is the assessment of physical and psychosocial problems of patients with pacemaker and effects of social - individual factors (such as age, sex, marital status, level of education,....) on the intensity of problems. in the study 60 patients (27 women, 33 men) that their mean age was 60.07 years, were studied. sampling was purposive and the samples were sele...

In this paper, we analyze the characteristics of the job shop scheduling problem. A new genetic algorithm for solving the agile job shop scheduling is presented to solve the job shop scheduling problem. Initial population is generated randomly. Two-row chromosome structure is adopted based on working procedure and machine distribution. The relevant crossover and mutation operation is also desig...

One of the goals envisioned by Grid computing is to make the execution of both computational and data-intensive problems possible. A key problem is finding the optimal set of resources to use for each submitted job, especially when we take network usage into consideration. To address this problem, we introduce an integer linear programming model, which incorporates the functions of job admissio...

We present a comprehensive complexity analysis of classical shop scheduling problems subject to various combinations of constraints imposed on the processing times of operations, the maximum number of operations per job, the upper bound on schedule length, and the problem type (taking values “open shop”, “job shop”, “mixed shop”). It is shown that in the infinite class of such problems there ex...

unemployment rate is one of the most leading among the important economic indicators. one of the most influential factors on unemployment rate is job quitting. experts consider two kinds of job quitting, intentionally and unintentionally. many studies have been done around the world, on the importance of job quitting, unemployment duration, and also on the costs caused by finding a new job. but...

Scheduling for job shop is very important in both fields of production management and combinatorial op-timization. However, it is quite difficult to achieve an optimal solution to this problem with traditional opti-mization approaches owing to the high computational complexity. The combination of several optimization criteria induces additional complexity and new problems. In this paper, we pro...