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101.
Job stress can lead to various system dysfunctions, but until now no reliable biomarkers for its assessment have been identified. Allostatic load (AL) is an index that enables the cumulative effect on the body of chronic stress to be assessed, and is derived from a set of relevant biological measures. In this study, a 13-parameter index (building on the original 10-item index) was used to examine the relationship between job strain and AL. Participants were 1219 healthy Chinese employees. Job strain was measured using the Job Content Questionnaire, and AL was assessed by various possible stress responses, including blood pressure, cholesterol, indicators of glucose metabolism, and hormone and inflammation markers. AL in the high job strain group differed sharply from that in the low job strain group. The AL score was positively associated with age and educational level. Several individual parameters also differed between the two groups. Men scored significantly higher on AL and cardiovascular and metabolic health outcomes, whereas for women the associations appeared in the biological indicators. Analyses indicated that decision latitude (DL) and job demands were significantly related to AL. Job demands correlated significantly with the primary biological indicators and DL with the secondary health outcomes. In conclusion, this study provides evidence of the value of measuring allostatic load in assessing the chronic effects of job stress. 相似文献
102.
103.
A batch is a subset of jobs which must be processed jointly in either serial or parallel form. The algorithmic aspects of
the batching scheduling problems have been extensively studied in the literature. This paper presents necessary and sufficient
conditions of the existence of optimal batch sequences for the single machine, batching, total weighted completion time scheduling
problems on two batching ways: (1) all jobs form one batch; (2) each batch contains a single job. This kind of conditions
can help us to recognize some special optimal schedules quickly.
Research supported by NSFC (10671183). 相似文献
104.
105.
高技术产业化协同过程探讨 总被引:2,自引:0,他引:2
本文用协同学理论研究了高技术产业化过程,并论述技术成熟度参数、高技术企业数量变化和随机因素在高技术产业化过程中的影响. 相似文献
106.
An ordered labeled tree is a tree in which the nodes are labeled and the left-to-right order among siblings is relevant. The edit distance between two ordered labeled trees is the minimum cost of transforming one tree into the other through a sequence of edit operations. We present techniques for speeding up the tree edit distance computation which are applicable to a family of algorithms based on closely related recursion strategies. These techniques aim to reduce repetitious steps in the original algorithms by exploring certain structural features in the tree. When these features exist in a large portion of the tree, the speedup due to our techniques would be significant. Viable examples for application include RNA secondary structure comparison and structured text comparison. 相似文献
107.
Let n,j,k be nonnegative integers. An n-fold L(j,k)-labeling of a graph G is an assignment f of sets of nonnegative integers of order n to the vertices of G such that, for any two vertices u,v and any two integers a∈f(u), b∈f(v), |a?b|≥j if uv∈E(G), and |a?b|≥k if u and v are distance two apart. The span of f is the absolute difference between the maximum and minimum integers used by f. The n-fold L(j,k)-labeling number of G is the minimum span over all n-fold L(j,k)-labelings of G. Let n,j,k and m be nonnegative integers. An n-fold circular m-L(j,k)-labeling of a graph G is an assignment f of subsets of {0,1,…,m?1} of order n to the vertices of G such that, for any two vertices u,v and any two integers a∈f(u), b∈f(v), min{|a?b|,m?|a?b|}≥j if uv∈E(G), and min{|a?b|,m?|a?b|}≥k if u and v are distance two apart. The minimum m such that G has an n-fold circular m-L(j,k)-labeling is called the n-fold circular L(j,k)-labeling number of G. This paper provides upper and lower bounds for the n-fold L(j,1)-labeling number and the n-fold circular L(j,1)-labeling number of the triangular lattice and determines the n-fold L(2,1)-labeling number and n-fold circular L(2,1)-labeling number of the triangular lattice for n≥3. 相似文献
108.
Feifeng Zheng E. Zhang Yinfeng Xu Wei-Chiang Hong 《Journal of Combinatorial Optimization》2014,27(1):182-198
This paper makes extended studies on the discrete problem of online scheduling and reliable lead time quotation (discrete Q-SLTQ) introduced by Keskinocak et al. (Manag. Sci. 47(2):264–279, 2001). We first relax the assumption on revenue function from a linear decreasing function to any decreasing function. We present an online deterministic strategy which is optimal in competitiveness for concave revenue functions. The above results are further extended to the continuous Q-SLTQ model where orders are released at arbitrary time points. For the discrete Q-SLTQ problem, if orders are with nonuniform lengths, we prove the nonexistence of online strategies with bounded competitive ratios; otherwise if orders are with unit length but various weights, we present an optimal online strategy. 相似文献
109.
110.
随着外部环境日渐复杂,新一代员工自我意识觉醒,信息化工作模式扩展,企业传统管理机制对员工绩效的影响越发有限。利用员工自我管理机制以及前摄性行为提升其自身创新绩效的管理路径有望成为持续增强企业创新实力的新方法。研究以国有科技型组织中的知识员工为样本,以主动反馈寻求行为为中介,探索前摄型人格对员工创新绩效的影响机制。研究结果表明,员工前摄型人格对其创新绩效具有正向影响;反馈寻求行为(询问与监测)完全中介前摄型人格对创新绩效的影响;主管对创新的支持正向调节直接反馈寻求行为——询问与创新绩效的关系,具有创新性同事的存在正向调节间接反馈寻求行为——监测与创新绩效的关系。 相似文献