首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   11篇
  免费   0篇
管理学   4篇
社会学   7篇
  2021年   1篇
  2017年   1篇
  2014年   1篇
  2013年   2篇
  2010年   1篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  1998年   1篇
  1985年   1篇
排序方式: 共有11条查询结果,搜索用时 109 毫秒
1.
Adult observers are sensitive to statistical regularities present in natural images. Developmentally, research has shown that children do not show sensitivity to these natural regularities until approximately 8–10 years of age. This finding is surprising given that even infants gradually encode a range of high‐level statistical regularities of their visual environment in the first year of life, We suggest that infants may in fact exhibit sensitivity to natural image statistics under circumstances where images of complex, natural textures, such as a photograph of rocks, are used as experimental stimuli and natural appearance is substantially manipulated. We tested this hypothesis by examining how infants' visual preference for real versus computer‐generated synthetic textures was modulated by contrast negation, which produces an image similar to a photographic negative. We observed that older infants' (9‐months of age) preferential looking behavior in this task was affected by contrast polarity, suggesting that the infant visual system is sensitive to deviations from natural texture appearance, including (1) discrepancies in appearance that differentiate natural and synthetic textures from one another and (2) the disruption of contrast polarity following negation. We discuss our results in the context of adult texture processing and the “perceptual narrowing” of visual recognition during the first year of life.  相似文献   
2.
Job-shop production in an individual and small-batch manufacturing environment demands producing simultaneously different products in many customised versions and in small numbers. The associated variability of the time-phased work content leads to a high degree of complexity and turbulence in the manufacturing process of such a production type. Therefore, production control becomes significantly more complicated, and many theories on how to cope fail in the real world. Despite the many technological and conceptual advances in the field of job-shop control over the past few decades, there is still a remarkable lack of practical control approaches for job-shop production. For this reason the Push-Kanban production control concept will be introduced in this article. It combines robust push scheduling along with a kanban-driven, decentralised inventory control mechanism to create a holistic control approach, integrating all production control tasks. Thus, it offers a feasible option for controlling job-shop production in industrial practice. This article examines the effectiveness of the concept by means of a simulation study based on real data.  相似文献   
3.
Abstract

Physical inactivity, diabetes, hypertension, dyslipidemia, smoking and obesity were associated with imbalance in oxidative stress, leading to endothelial dysfunction. Such dysfunction is present in both cardiovascular disease (CVD) and erectile dysfunction (ED). ED is the persistent inability to achieve or sustain an erection sufficient for satisfactory sexual performance and is one of the first manifestations of endothelial damage in men with CVD risk factors. The purpose of this article is to review the results of studies involving physical activity, CVD, endothelial dysfunction and ED in order to verify its applicability for improving the health and quality of life of men with such disorders. There is consistent evidence that endothelial damage is intimately linked to ED, and this manifestation seems to be associated with the appearance CVDs. On the other hand, physical activity has been pointed out as an important clinical strategy in the prevention and treatment of CVDs and ED mainly associated with improvement of endothelial function. However, further experimental and clinical prospective investigations are needed to test the role of physical exercises in the modulation of endothelial function and their implications on erectile function and the appearance of CVDs.  相似文献   
4.
The decision to dismiss a coach is challenging because poor performance tends to coincide with both bad luck and low coaching ability. We differentiate between dismissals following actual poor performance on the pitch (wise dismissals) and dismissals following seemingly poor performance due to bad luck (unwise dismissals). To categorize dismissals, we use “expected goals,” which are less vulnerable to random variation in match outcomes. Using data from European football, we find that wise dismissals increase subsequent performance compared to a control group of nondismissals with similarly poor performance on the pitch. However, unwise dismissals do not improve subsequent performance compared to a control group with similar strings of bad luck. (JEL D81, J44, L83)  相似文献   
5.
Job Shop Scheduling With Deadlines   总被引:1,自引:0,他引:1  
In this paper we deal with a variant of the Job ShopScheduling Problem. We consider the addition of release dates anddeadlines to be met by all jobs. The objective is makespanminimization if there are no tardy jobs, and tardiness minimizationotherwise. The problem is approached by using a Shifting Bottleneckstrategy. The presence of deadlines motivates an iterative use of aparticular one machine problem which is solved optimally. Theoverall procedure is heuristic and exhibits a good trade-off betweencomputing time and solution quality.  相似文献   
6.
Bourdieu's (1986) General Theory of the Economy of Practices assumes that people perpetually transform tangible and intangible forms of capital according to certain ‘laws of conversion’. On this background, and combining sociology and micro-economics, we analyze specific strings of capital conversion in time and space. More specifically, we raise the question: How do private entrepreneurs transform local social capital into economic capital? We combine in-depth interviews with four private entrepreneurs in rural Denmark with Prisoner's Dilemma game theory. Thus each of our cases illustrates one of the outcomes in the PD matrix. In this way we explain why only one of the four entrepreneurs succeeds in capitalizing social capital.  相似文献   
7.
We derive by means of disjunctive programming the convex hull representation of logical conditions called cardinality rules given by Hong and Hooker (1999), and specify an efficient separation algorithm for the family of inequalities defining the convex hull. We then extend both the convex hull characterization and the efficient separation procedure to more general logical conditions.  相似文献   
8.
9.
High dropout rates threaten the validity of longitudinal studies involving participants suffering from substance use disorder (SUD). The objective of this article is to evaluate strategies to improve retention. The data analysis was based on an ongoing study of long-term recovery of neurocognitive and psychosocial functions. We used traditional strategies to enhance the contact rate. Common factors in psychosocial treatments and biweekly Short Message Service (SMS; text messaging) monitoring were added to further increase the contact rate. The participants (n = 146) were recruited from treatment facilities for SUD. Assessments were measured at 3 months, 6 months, 9 months, and 12 months. This study was successful in retaining a cohort of participants who are typically characterized as having a negative prognosis because of their unstable living arrangements and incomes. Compared to those using GHB, addictive medications, and opiates, the retention rate was the lowest among participants with severe alcohol use disorder (42%).  相似文献   
10.
Software developed and producedin open source projects has become an importantcompetitor in the software industry. Since itcan be downloaded for free and no wages arepaid to developers, the open source endeavorseems to rest on voluntary contributions byhobbyists. In the discussion of this puzzle twobasic patterns of argumentation stand out. Inwhat we call rent-seeker approaches, emphasisis put on the fact that although no wages arepaid to contributors, other pay-offs may turntheir effort into a profitable investment. Inwhat we call donator approaches the point ismade that many people contribute to open sourceprojects without expecting to ever receive anyindividual rewards.We argue that the basic institutionalinnovation in open source has been the craftingof a governance structure, which enablesrent-seeking without crowding out donations.The focus of the presented analysis lies on thespecific institutional mechanisms, by which theopen source governance structure achieves toreconcile the interests of rent-seekers anddonators.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号