Longest Job Research Articles

EOTE-FSC: An efficient offloaded task execution for fog enabled smart cities.

Smart cities provide ease in lifestyle to their community members with the help of Information and Communication Technology (ICT). It provides better water, waste and energy management, enhances the security and safety of its citizens and offers better health facilities. Most of these applications are based on IoT-based sensor networks, that are deployed in different areas of applications according to their demand. Due to limited processing capabilities, sensor nodes cannot process multiple tasks simultaneously and need to offload some of their tasks to remotely placed cloud servers, which may cause delays. To reduce the delay, computing nodes are placed in different vicinitys acting as fog-computing nodes are used, to execute the offloaded tasks. It has been observed that the offloaded tasks are not uniformly received by fog computing nodes and some fog nodes may receive more tasks as some may receive less number of tasks. This may cause an increase in overall task execution time. Furthermore, these tasks comprise different priority levels and must be executed before their deadline. In this work, an Efficient Offloaded Task Execution for Fog enabled Smart cities (EOTE - FSC) is proposed. EOTE - FSC proposes a load balancing mechanism by modifying the greedy algorithm to efficiently distribute the offloaded tasks to its attached fog nodes to reduce the overall task execution time. This results in the successful execution of most of the tasks within their deadline. In addition, EOTE - FSC modifies the task sequencing with a deadline algorithm for the fog node to optimally execute the offloaded tasks in such a way that most of the high-priority tasks are entertained. The load balancing results of EOTE - FSC are compared with state-of-the-art well-known Round Robin, Greedy, Round Robin with longest job first, and Round Robin with shortest job first algorithms. However, fog computing results of EOTE - FSC are compared with the First Come First Serve algorithm. The results show that the EOTE - FSC effectively offloaded the tasks on fog nodes and the maximum load on the fog computing nodes is reduced up to 29%, 27.3%, 23%, and 24.4% as compared to Round Robin, Greedy, Round Robin with LJF and Round Robin with SJF algorithms respectively. However, task execution in the proposed EOTE - FSC executes a maximum number of offloaded high-priority tasks as compared to the FCFS algorithm within the same computing capacity of fog nodes.

TMPAD: Time-Slot-Based Medium Access Control Protocol to Meet Adaptive Data Requirements for Trusted Nodes in Fog-Enabled Smart Cities

The popularity of fog-enabled smart cities is increasing due to the advantages provided by modern communication and information technologies, which contribute to an improved quality of life. Wireless networks make them more vulnerable when the network is under malicious attacks that cause a collision in the medium. Furthermore, diverse applications of smart cities demand a contention-free medium access control (MAC) protocol to meet adaptive data requirements. In this work, a time-slot-based medium access control protocol to meet adaptive data requirements (TMPAD) for IoT nodes in fog-enabled smart cities is proposed. TMPAD proposes a trust mechanism to differentiate malicious and legitimate data requests. In addition, it accommodates more legitimate data-requesting nodes to transfer their data during a session by applying the technique for order performance by similarity to ideal solution (TOPSIS) and 0/1 knapsack algorithm. The performance of TMPAD is compared with well-known techniques such as first come first serve (FCFS), shortest job first (SJF), and longest job first (LJF) in different prospective scenarios. The results show that TMPAD scrutinizes more data-requesting nodes in slot allocation, allowing more data transmission in a session, with better mean trust value, as compared to other algorithms.

The association between shift work exposure and cognitive impairment among middle-aged and older adults: Results from the Canadian Longitudinal Study on Aging (CLSA).

Shift work, especially rotating and night shift work, has been linked to a wide range of detrimental health outcomes. Occupational factors like shift work and their potential impact on cognitive functions have received little attention, and the evidence is inconclusive. The objective of our study is to explore associations between shift work exposure and cognitive impairment indicators based on comparisons with the normative standards from the Canadian population. Cross-sectional analyses were performed using baseline Canadian Longitudinal Study on Aging database, including 47,811 middle-aged and older adults (45-85 years). Three derived shift work variables were utilized: ever exposed to shift work, shift work exposure in longest job, and shift work exposure in current job. Four cognitive function tests were utilized, Rey Auditory Verbal Learning Tests (immediate and delayed) representing memory domain, and Animal Fluency, and Mental Alteration, representing the executive function domain. All cognitive test scores included in study were normalized and adjusted for the participant's age, sex, education and language of test administration (English and French), which were then compared to normative data to create "cognitive impairment' variables. Unadjusted and adjusted multivariable logistic regression models were used to determine associations between shift work variables and cognitive impairment individually (memory and executive function domains), and also for overall cognitive impairment. Overall, one in every five individuals (21%) reported having been exposed to some kind of shift work during their jobs. Exposure to night shift work (both current and longest job) was associated with overall cognitive impairment. In terms of domain-based measures, night shift work (longest job) was associated with memory function impairment, and those exposed to rotating shift work (both current and longest job) showed impairment on executive function measures, when compared to daytime workers. This study suggests disruption to the circadian rhythm, due to shift work has negative impact on cognitive function in middle-aged and older adults and this warrants further investigation.

The Association Between Shift Work Exposure and Frailty Among Middle-Aged and Older Adults: Results From the Canadian Longitudinal Study on Aging.

To investigate the association between shift work exposure and frailty. Longitudinal secondary data analyses were performed using Canadian Longitudinal Study on Aging. Individuals aged 45-85 years were included at baseline (N = 47,740). Primary SW variables were derived at baseline: ever exposed to SW, SW exposure in longest job, and SW exposure in current job. Multinomial regression models were constructed to evaluate the association between SW and frailty at 3 years of follow-up. Participants ever exposed to SW were associated with frailty compared to those who worked only daytime. Particularly, females worked in rotating shifts in their longest jobs were more likely to be classified as frail compared to those who worked only daytime. This study suggests that SW may play a role in development of frailty and this warrants further investigation.

The association between shift work exposure and the variations in age at natural menopause among adult Canadian workers: results from the Canadian Longitudinal Study on Aging (CLSA).

A wide range of negative health outcomes have been associated with shift work (SW) particularly night and rotating SW. However, little is known about effects of SW exposure on reproductive health outcomes. The objective of our study is to prospectively investigate the association between SW exposure and the variations in age at natural menopause among adult Canadian workers. Secondary data analyses were performed using the Canadian Longitudinal Study on Aging database. Premenopausal women (N = 3,688) at baseline were followed prospectively for 3 years. Three derived variables were used to measure SW primary exposure: 1) ever exposed to SW, 2) SW exposure in current job, and 3) SW exposure in the longest job. Cox proportional hazard regression models were used to evaluate risk of variations in age at natural menopause after adjusting for potential confounders. One out of five women (20%) reported to be ever exposed to SW during their jobs. Overall, women who were ever exposed to SW were significantly associated with a delayed onset of menopause compared with daytime workers (hazard ratios [HR] = 0.77, 95% CI, 0.61-0.98). Particularly, when compared with daytime workers, rotating shift worker in the current and longest job were significantly related to delayed onset of menopause (HR = 0.64, 95% CI, 0.46-0.89 and HR = 0.65, 95% CI, 0.49-0.86), respectively. Our results suggest a relationship between rotating shift and delayed onset of menopause. We speculate that disruptive circadian stimuli may play a role in menopausal onset and this warrants further investigation.Video Summary:http://links.lww.com/MENO/A940 .

Estimating the returns to education in a chronically depressed labour market: the case of Kosovo

PurposeThis paper aims to investigate whether the conventional approach to estimating the private and social rates of return to education generates reliable findings when used in economies with chronically depressed labour markets.Design/methodology/approachConventional techniques (the Mincer earnings function and the discounting method) are used to provide initial estimates of the private and social returns to education in Kosovo. However, this study argues that in countries with chronically depressed labour markets, such as in Kosovo, the conventional approach is likely to significantly underestimate the private and social returns from achieving a higher level of educational attainment. This study extends the estimation approach to take into account the greater probability of more highly educated Kosovars being: employed, employed in the formal and public sectors and having longer job tenure.FindingsThe extended approach to estimating rates of return to schooling generates higher private and social rates of return to education than the conventional approach. Moreover, in contrast to the findings of the conventional approach, the revised approach suggests that private and social rates of return are highest from completion of upper secondary and tertiary education.Research limitations/implicationsThe results indicate that if governments in economies with chronically depressed labour markets decide upon their educational priorities based on unadjusted rates of return, then resources may be misallocated.Originality/valueThe analysis presented in this paper suggests that conventional approaches to estimating private and social rates of return to education are not suitable for use in economies with chronically depressed labour markets. In addition, the paper provides the first comprehensive analysis of the rates of return to education in Kosovo. These results are used to provide a critique of the Kosovo Government’s recent educational priorities.

The Flip Side of Turnover: Employment Transitions and Occupational Attachment Among Low-Wage Care Workers in the United States

Scholars have explored the ways that conventional economic theory does not fully explain the distribution and characteristics of caring labor – the work, unpaid and paid, of caring for those who are young, elderly, or disabled. This paper explores a critical dimension of paid care – high turnover rates in the lowest-wage segment of the sector (including childcare, nursing homes, home health). Using longitudinal data from the 2008 Survey of Income and Program Participation (SIPP) in the US, it examines the “flip side” of that turnover by comparing occupational mobility among low-wage care workers to that of other low-wage service workers. The findings indicate that patterns of occupational transition among care workers are distinct in important ways. Understanding occupational attachment among paid care workers is critical to developing theoretical models about care and to creating care-specific policies to address employee turnover and its negative impact on care quality. HIGHLIGHTS High turnover in low-wage jobs in care-related fields has a negative impact on the quality of care. Low-wage care workers have longer job tenures and are more likely to stay in their field than other low-wage workers. Low-wage care workers experience more upward mobility than food service and cleaning workers, but less than office and sales workers. Low-wage care workers have high rates of transition to a period of not working. There is evidence of higher levels of occupational attachment among low-wage care workers than among other low-wage service workers.

Efficient task scheduling on virtual machine in cloud computing environment

PurposeCloud users can access services at anytime from anywhere in the world. On average, Google now processes more than 40,000 searches every second, which is approximately 3.5 billion searches per day. The diverse and vast amounts of data are generated with the development of next-generation information technologies such as cryptocurrency, internet of things and big data. To execute such applications, it is needed to design an efficient scheduling algorithm that considers the quality of service parameters like utilization, makespan and response time. Therefore, this paper aims to propose a novel Efficient Static Task Allocation (ESTA) algorithm, which optimizes average utilization.Design/methodology/approachCloud computing provides resources such as virtual machine, network, storage, etc. over the internet. Cloud computing follows the pay-per-use billing model. To achieve efficient task allocation, scheduling algorithm problems should be interacted and tackled through efficient task distribution on the resources. The methodology of ESTA algorithm is based on minimum completion time approach. ESTA intelligently maps the batch of independent tasks (cloudlets) on heterogeneous virtual machines and optimizes their utilization in infrastructure as a service cloud computing.FindingsTo evaluate the performance of ESTA, the simulation study is compared with Min-Min, load balancing strategy with migration cost, Longest job in the fastest resource-shortest job in the fastest resource, sufferage, minimum completion time (MCT), minimum execution time and opportunistic load balancing on account of makespan, utilization and response time.Originality/valueThe simulation result reveals that the ESTA algorithm consistently superior performs under varying of batch independent of cloudlets and the number of virtual machines’ test conditions.

Characterizing Short-Term Jobs in a Population-Based Study.

Work histories generally cover all jobs held for ≥1 year. However, it may be time and cost prohibitive to conduct a detailed exposure assessment for each such job. While disregarding short-term jobs can reduce the assessment burden, this can be problematic if those jobs contribute important exposure information towards understanding disease aetiology. To characterize short-term jobs, defined as lasting more than 1 year, but less than 2 years, in a population-based study conducted in Montreal, Canada. In 2005-2012, we collected work histories for some 4000 participants in a case-control study of prostate cancer. Overall, subjects had held 19 462 paid jobs lasting ≥1 year, including 3655 short-term jobs. Using information from interviews and from the Canadian Classification and Dictionary of Occupations, we characterized short-term jobs and compared them to jobs held ≥2 years. Short-term jobs represented <4% of subjects' work years on average. Forty-five per cent of subjects had at least one short-term job; of these, 49% had one, 24% had two, and 27% had at least three. Half of all short-term jobs had been held before the age of 24. Short-term jobs entailed more often exposure to fumes, odours, dust, and/or poor ventilation than longer jobs (17 versus 13%), as well as outdoor work (10 versus 5%) and heavy physical activity (16 versus 12%). Short-term jobs occurred often in early careers and more frequently entailed potentially hazardous exposures than longer-held jobs. However, as they represented a small proportion of work years, excluding them should have a marginal impact on lifetime exposure assessment.

Occupational Exposures and Computed Tomographic Imaging Characteristics in the SPIROMICS Cohort.

Quantitative computed tomographic (CT) imaging can aid in chronic obstructive pulmonary disease (COPD) phenotyping. Few studies have identified whether occupational exposures are associated with distinct CT imaging characteristics. To examine the association between occupational exposures and CT-measured patterns of disease in the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study). Participants underwent whole-lung multidetector helical CT at full inspiration and expiration. The association between occupational exposures (self-report of exposure to vapors, gas, dust, or fumes [VGDF] at the longest job) and CT metrics of emphysema (percentage of total voxels < -950 Hounsfield units at total lung capacity), large airways (wall area percent [WAP] and square-root wall area of a single hypothetical airway with an internal perimeter of 10 mm [Pi10]), and small airways (percent air trapping [percent total voxels < -856 Hounsfield units at residual volume] and parametric response mapping of functional small-airway abnormality [PRM fSAD]) were explored by multivariate linear regression, and for central airway measures by generalized estimating equations to account for multiple measurements per individual. Models were adjusted for age, sex, race, current smoking status, pack-years of smoking, body mass index, and site. Airway measurements were additionally adjusted for total lung volume. A total of 2,736 participants with available occupational exposure data (n = 927 without airflow obstruction and 1,809 with COPD) were included. The mean age was 64 years, 78% were white, and 54% were male. Forty percent reported current smoking, and mean (SD) pack-years was 49.3 (26.9). Mean (SD) post-bronchodilator forced expiratory volume in 1 second (FEV1) was 73 (27) % predicted. Forty-nine percent reported VGDF exposure. VGDF exposure was associated with higher emphysema (β = 1.17; 95% confidence interval [CI], 0.44-1.89), greater large-airway disease as measured by WAP (segmental β = 0.487 [95% CI, 0.320-0.654]; subsegmental β = 0.400 [95% CI, 0.275-0.527]) and Pi10 (β = 0.008; 95% CI, 0.002-0.014), and greater small-airway disease was measured by air trapping (β = 2.60; 95% CI, 1.11-4.09) and was nominally associated with an increase in PRM fSAD (β = 1.45; 95% CI, 0.31-2.60). These findings correspond to higher odds of percent emphysema, WAP, and air trapping above the 95th percentile of measurements in nonsmoking control subjects in individuals reporting VGDF exposure. In an analysis of SPIROMICS participants, we found that VGDF exposure in the longest job was associated with an increase in emphysema, and in large- and small-airway disease, as measured by quantitative CT imaging.

MTTDFR-SJFR: A Combinatorial Rule Approach to Balance Tradeoff Between Flowtime, Makespan, Delayed Jobs, Total Tardiness and Utilization

In order to fully utilize the Grid resources, implementing a good scheduling algorithm is really important. Currently, some of the well-known researches and enterprise schedulers have applied Priority Rule (PR) schedulers to manage the Grid jobs because they are simple and easy to implement. To date, there is no strong performance justification or proof given on why these specific PR algorithms are preferred compared to other PR algorithms. For example, five PR algorithms; First Come First Serve (FCFS), Longest Job First (LJF), Shortest Job First (SJF), Earliest Deadline First (EDF) and Minimum Time To Deadline (MTTD) have been proposed. However, none of these algorithms perform well in every metrics of performance. An attempt to improve their performance has been made using Combinatorial Rule (CR) which is the combination of more than one PR. Unfortunately, the current implementation of CR only focuses on two performance metrics which are flowtime and makespan, while sacrificing the others. In order to tackle the aforementioned problem, this paper introduces Minimum Time To Deadline to Fastest Resource - Shortest Job to Fastest Resource (MTTDFR-SJFR), a new CR scheduler that performs better than other CR algorithms tested within the scope. To achieve high performance, a combination of PR with Fastest Resource (FR) resource selection scheme that further improve the performance is proposed. Graphical results obtained from experimental simulation showed the superiority of the proposed CR algorithm in term of overall performance, compared to other CR as well as the original PR.

Mass incarceration, race inequality, and health: Expanding concepts and assessing impacts on well-being

We explore race differences in how individuals experience mass incarceration, as well as in mass incarceration's impacts on measures of well-being that are recognized as major social determinants of health. We draw on baseline data from a sample of 302 men and women recently released from prison/jail or placed directly onto probation in New Haven, Connecticut (CT) for drug related offenses and followed at 6-month intervals for two years (2011–2014). We describe race differences in experiences of mass incarceration and in its impacts on well-being; and we conduct mediation analyses to analyze relationships among race, mass incarceration, and well-being. Blacks reported fewer adult convictions than whites, but an average of 2.5 more adult incarcerations. Blacks were more likely to have been incarcerated as a juvenile, spent time in a juvenile facility and in an adult facility as a juvenile, been on parole, and experienced multiple forms of surveillance. Whites were more likely to report being caught by the police doing something illegal but let go. Blacks were more likely to report any impact of incarceration on education, and dropping out of school, leaving a job, leaving their longest job, and becoming estranged from a family member due to incarceration. Whites were more likely to avoid getting needed health or social services for fear of arrest. Overall, Blacks reported a larger number of impacts of criminal justice involvement on well-being than whites. Number of adult incarcerations and of surveillance types, and being incarcerated as a juvenile, each mediated the relationship among race, mass incarceration, and well-being. Though more research is necessary, experiences of mass incarceration appear to vary by race and these differences, in turn, have implications for interventions aimed at addressing the impacts of mass incarceration on health and well-being.

Evidence-based practice and knowledge utilisation – a study of attitudes and practices among social workers in Germany

ABSTRACTThis study aimed to add to the limited empirical knowledge base on evidence-based practice (EBP) and social work in Germany. Using a regional sample of 158 social workers that were recruited through stratified sampling procedures, the study examined knowledge utilisation as well as attitudes toward the use of research-based practice methods, administering a normed and internationally recognised instrument, the Evidence-Based Practice Attitude Scale (EBPAS). It further examined practitioner-level predictors of openness toward research-based methods. Findings indicated limited familiarity with the concept of EBP and showed that research and theory were not primary sources of knowledge to guide practice. Yet, attitudes toward research-based methods were overall positive and indicated considerable openness if methods made sense, were appealing, and sufficient training and support were provided. Scepticism and negative attitudes were evident in some areas (e.g. manualization, requirements). Multivariate linear regression indicated that individuals in leadership positions held more positive attitudes while a longer job tenure was inversely related to openness, approaching significance. Findings of the study are compared to the U.S. normative sample as well as a prior German study using the EBPAS. Implications for knowledge development in the discipline of social work in Germany are discussed.

Applying Queueing Theory for the Optimization of a Banking Model

The purpose of this paper is to investigate waiting times at banking firms to design a system to optimise the overall banking experience. Queueing analysis and queuing theory will be investigated and applied in order to improve customer experience whilst maximising profits. Different queueing strategies will be implemented using waiting time as a performance measurement. In order to find the most efficient solution the following queuing methods will be investigated: First in First out (FIFO), Last in First out (LIFO), Shortest Job First (SJF), Longest Job First (LJF), most profitable job first and priority queues. After investigation, design and simulation, queuing strategies will be implemented on a real world banking scenario whilst introducing banking traffic at different times of the day as well as disturbances such as tellers going offline. A practical design includes a Field Programmable Gate Array (FPGA) in order to simulate the banking scenario. The FPGA approach will provide a mobile solution for the optimization of queueing in a banking firm which could later be implemented in a banking firm for a better banking experience. Based on results obtained, the SJF method produces the best customer satisfaction, whilst most profitable job first queues maximizes profits.

Self-perceived vision in farming, forestry, and fishing occupations

ABSTRACTUsing data from the 2005–2006 and 2007–2008 NHANES questionnaires, we evaluated self-perceived vision difficulty in individuals with a history of farming, forestry, and fishing (FFF) occupations. A self-perceived vision difficulty indicator was derived from responses to 3 separate measures. Those indicating farming, forestry, or fishing as longest job worked were classified as having an FFF history and compared to those reporting any other occupation. Logistic regression analyses utilizing NHANES sampling weights were conducted. After controlling for age, gender, race/ethnicity, education, and income-to-poverty ratio, those with an FFF history were 76% more likely to report vision difficulty than those having an alternate occupational history. Personal protective equipment and routine optometric examination may be particularly prudent for this occupational group.

Respiratory Cancer and Non-Malignant Respiratory Disease-Related Mortality among Older Construction Workers-Findings from the Health and Retirement Study.

ObjectiveThis study explored the risk of respiratory cancer and non-malignant respiratory disease (NMRD)-related mortality among older construction workers.MethodsAnalyzed data from the 1992–2010 RAND Health and Retirement Study (HRS) and the HRS National Death Index – Cause of Death file. About 25,183 workers aged 50 years and older were examined, including 5,447 decedents and 19,736 survivors, of which 1,460 reported their longest job was in construction. Multinomial logistic regression assessed the differences in mortality between workers’ longest occupations, controlling for confounders.ResultsAfter adjusting for smoking and demographics, construction workers were almost twice as likely to die from respiratory cancer (OR = 1.65; CI: 1.10–2.47) or NMRD (OR = 1.73; CI: 1.16–2.58) compared to white-collar workers.ConclusionsThis study adds to the growing evidence that respiratory cancer and NMRD are frequently associated with construction exposure.

Association between shift work and obesity according to body fat percentage in Korean wage workers: data from the fourth and the fifth Korea National Health and Nutrition Examination Survey (KNHANES 2008-2011).

BackgroundHealth problems in shift workers vary including obesity acting as a risk factor in cerebrovascular diseases. Recent studies have commonly determined the prevalence of obesity in shift workers on the basis of body mass index. The accuracy of BMI for diagnosing obesity are still limited apparently. Consequently, this study aimed to determine the relationship between shift work and obesity according to the total body fat percentage in Korean wage workers.MethodsFrom the Fourth and the Fifth Korea National Health and Nutrition Examination Survey (2008–2011), after military personnel were excluded, a total of 2952 wage workers (20 ≤ age ≤ 65) whose current jobs were their longest jobs were selected as subjects of the study. The total body fat percentage was used to determine the obesity standards (≥25.7 % in males and ≥36.0 % in females). The subjects were divided into groups by gender and work type (manual vs non-manual), and chi-squared test was used to evaluate the relationship between socio-economic, health behavior, and work-related factors, on the one hand, and obesity, on the other. In addition, multivariate logistic regression analysis was performed to examine the effects of shift work on obesity.ResultsWhen other factors were controlled for, the risk of obesity in shift work showed a statistically significant increase (odds ratio = 1.779, 95 % confidence interval = 1.050-3.015) in the male manual worker group. However, there were no significant results in the male non-manual and female worker groups.ConclusionShift work was related to a higher risk of obesity in the Korean male manual worker group.

Occupational exposures are associated with worse morbidity in patients with chronic obstructive pulmonary disease.

Links between occupational exposures and morbidity in individuals with established chronic obstructive pulmonary disease (COPD) remain unclear. To determine the impact of occupational exposures on COPD morbidity. A job exposure matrix (JEM) determined occupational exposure likelihood based on longest job in current/former smokers (n = 1,075) recruited as part of the Subpopulations and Intermediate Outcomes in COPD Study, of whom 721 had established COPD. Bivariate and multivariate linear regression models estimated the association of occupational exposure with COPD, and among those with established disease, the occupational exposure associations with 6-minute-walk distance (6MWD), the Modified Medical Research Council Dyspnea Scale (mMRC), the COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), 12-item Short-Form Physical Component (SF-12), and COPD exacerbations requiring health care utilization, adjusting for demographics, current smoking status, and cumulative pack-years. An intermediate/high risk of occupational exposure by JEM was found in 38% of participants. In multivariate analysis, those with job exposures had higher odds of COPD (odds ratio, 1.44; 95% confidence interval, 1.04-1.97). Among those with COPD, job exposures were associated with shorter 6MWDs (-26.0 m; P = 0.006); worse scores for mMRC (0.23; P = 0.004), CAT (1.8; P = 0.003), SGRQ (4.5; P = 0.003), and SF-12 Physical (-3.3; P < 0.0001); and greater odds of exacerbation requiring health care utilization (odds ratio, 1.55; P = 0.03). Accounting for smoking, occupational exposure was associated with COPD risk and, for those with established disease, shorter walk distance, greater breathlessness, worse quality of life, and increased exacerbation risk. Clinicians should obtain occupational histories from patients with COPD because work-related exposures may influence disease burden.

How to Get a Longer Job? Roles of Human and Social Capital in the Japanese Labor Market

AbstractThis article investigates the roles of human and social capital played in the Japanese labor market. Our research question is whether they interact to accelerate or decelerate each other to provide first jobs of a long duration. Based on the literature, we focus on the bonding functions of friends and relatives. Using the 2005 Social Stratification and Social Mobility Survey Data, we measure human capital by educational attainment (college education) and social capital by job search methods (using friends or relatives). The dependent variable is the hazard rate of turnover from the first job. We find that social capital especially benefits those with low human capital (high school graduates). When friends or relatives introduce workers to jobs, high school graduates tended to stay longer in their first jobs and had a lower turnover than college graduates did. This means that social capital decelerated effects of human capital. Therefore, in the Japanese labor market, social capital plays a complementary role in mitigating educational disadvantage.

Scheduling games on uniform machines with activation cost

In this paper, we investigate job scheduling games on uniform machines. Activating each machine incurs an activation cost in accordance with its speed. Jobs are self-decision-making players choosing machines with the objective of minimizing their own individual cost. Here, a job's individual cost is defined as the load of its chosen machine plus its activation cost, which is proportionally shared with respect to its size. We first propose an algorithm when there are m kinds of unlimited number of uniform machines, and it is proved to be a Nash Equilibrium (NE) algorithm by using the induction method. Because of equilibria always being far from optimal solutions, the inefficiency of pure NE is measured with the social objective of minimizing the maximum individual cost. Assuming that the longest job is α times as large as the unit activation cost, together with α≥a2, we obtain that both the Price of Anarchy (PoA) and Price of Stability (PoS) are equal to 1. Otherwise, they are bounded by (α+1)/2α. Finally, we provide an example to illustrate the tight bound.