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1.
在食品安全威胁下,农户重新定义了“为自家生产”和“为市场生产”的差别化生产行为。基于经济理性行为假设认为农户存在以确保自家食品安全为动机的生存理性。根据在5省区收集的827份农村入户调研数据,对农户差别化生产行为进行具体分析,描述了差别化生产行为总体特征,并测量农户食品安全自我保护意识、威胁感知程度和信息渠道等因素。运用Probit模型验证了命题:以食品安全自我保护意识为特征的生存理性,支配了农户为确保自家消费安全而进行的差别化生产。  相似文献   
2.
This paper provides the first systematic look into the existing research on performance management (PM) practices employed in lean manufacturing organisations (LMOs). It adopts a systematic review method to examine the evidence generated in the period 2004 – 2015 and uses a comprehensive PM framework to synthesise the findings. The results suggest that PM practices that have the most prominent role in LMOs are those that, firstly, are located closest to front-line actions and, secondly, explicitly address operational realities. This calls into question the primacy of accounting-driven controls in LMOs, suggesting that operational controls may be more effective than top-down accounting-based PM practices. The results also confirm the bias towards operational-level issues but suggest that LMOs may integrate the operational and the strategic levels by using PM practices that drive organisational learning through employee involvement and engagement.  相似文献   
3.
制造业是我国国民经济的支柱产业,但也是环境污染物排放的主要来源、能源消耗主体和温室气体排放大户。制造系统高能耗、高物耗、高碳排放的加工过程是造成制造业碳排放量大的重要原因。生产单元作为制造系统的加工的主体,其碳排放量的核算是确定整个制造系统乃至制造业碳排放总量的关键。本文首先对生产单元的原材料、电能、辅助物料及废屑处理所引起的碳排放进行分析,确定生产单元的碳排放源;其次,产品合格率的不同会造成生产单元输入及输出的成品/半成品数量的差异,进而影响生产单元单位产品的碳排放量,在此基础上,综合考虑了原材料、电能、辅助物料及废屑处理的碳排放情况,构建了给定工艺流程下生产单元碳排放核算模型。最后,结合一汽车排气装置加工实例,分别核算加工过程中九个生产单元的碳排放量,验证了模型的可行性。  相似文献   
4.
《共产党宣言》蕴含着深刻的生态思想,其体系以人、社会、自然整体为背景,其核心观点认为生态问题是由资本主义生产方式引起的.马克思在唯物史观视野下,科学论证了资产阶级的所有制必然灭亡、共产主义必然实现的历史发展逻辑,廓清了人与人、人与自然之间双重和解的演化路径.其中关于科技提升、市场拓展、交通和通信发展等引起世界市场“生态扩张”的思想,对全球化程度日益加深境况下“生态文明”和“人类命运共同体”的构建具有重大的理论和实践指导价值.  相似文献   
5.
基于技术水平和规模化水平时空差异,收集不同养殖模式生长周期、出栏量等关键数据,对全国和各省生猪养殖碳排放量进行估算。结果表明,1998-2015年,全国生猪养殖碳排放量呈震荡上升趋势,从1.08亿吨CO2当量增加到1.33亿吨 CO2当量;规模化养殖逐渐取代散养成为碳排放主体,2015年其排放量占比达到73.57%;四川、湖南、河南、山东等生猪主产省份碳排放量居全国前列;LMDI模型的分解结果表明,生猪产量扩张是碳排放增长的主要驱动力,推动碳排放量增长43.93%,技术进步和养殖规模化则将碳排放增长削减了近一半。因此,提高养殖技术、推动规模化养殖、应用沼气池处理粪污将是重要的温室气体减排措施。  相似文献   
6.
以市场需求和市场价格随机波动的二级供应链为研究对象,寻找其在信息不对称条件下绩效优化的路径。通过显示原理分别构建生产成本和销售成本信息不对称时应急供应链的数量折扣契约模型,得到最优订货量与最佳批发价策略。通过具体的算例加以验证,分析了信息不对称程度对供应链上成员及整个供应链绩效的影响。研究结果表明:当突发事件造成市场价格随机波动和市场需求变化时,供应链上的跟随者能从隐瞒私人信息中获利。但当市场需求增大时,整个供应链绩效受损,反之则反是。这与以往研究在市场需求随机、市场价格固定和信息不对称条件下的结论迥异。  相似文献   
7.
Introduction: Tadalafil is a promising phosphodiesterase (PDE) 5 inhibitor prescribed for erectile dysfunction (ED). Daily low dose (5?mg) of tadalafil has also been used for the treatment of male lower urinary tract symptoms (LUTS) associated with benign prostate hyperplasia (BPH). PDE5 inhibitors induce relaxation of smooth muscle cells in the urethra, prostate, bladder neck, and blood vessels. The aim of this study was to investigate the efficacy of tadalafil on vessels endothelial function, in patients with male LUTS symptoms associated with BPH.

Methods: The Institutional Review Board (IRB) approved this clinical study and informed consents had been obtained from 81 BPH patients.

The following male LUTS parameters: international prostate symptom score (IPSS), overactive bladder symptom score (OABSS), voiding volume, max and mean voiding flow on voiding flowmetry examination and post-voiding residual urine (RU) were compared at 0, 1, 3, 6, and 12 months after a daily dose of 5?mg tadalafil.

In addition, erectile function was evaluated by the sexual health inventory for men (SHIM) score and vessels endothelial function and peripheral neuropathy were assessed by the brachial-ankle pulse wave velocity (baPWV), ankle brachial index (ABI), and vibration perception threshold (VPT) at 0, 3, 6, and 12 months after treatment.

Results: The mean age of 81 patients was 66.4?±?11.4 years old. Their prostate size was 30.2?±?22.1?ml.

Male LUTS parameters including IPSS, OABSS, and RU showed significant improvement from 1 to 12 months after tadalafil administration. Max and mean voiding flow was significantly increased at 6 months after tadalafil treatment.

The SHIM score showed significant improvement after 3 months. Whilst, the results of baPWV also showed significant improvement from 3 to 12 months. ABI was also significantly improved at 6 months. However, there was no change in the VPT at any time point.

Conclusions: Tadalafil is effective for both male LUTS and ED. It is also shown that tadalafil improves baPWV, which we can conclude that higher vessels elasticity has been obtained. This major finding of this study shows that tadalafil has the potency to improve vessels endothelial dysfunction in patients with BPH.  相似文献   
8.
Beginning in the 1980s, and continuing for over three decades since, a particular generation of Tibetans from the Northeastern Tibetan region known as Amdo, and particularly from the northern parts of China’s Qinghai province, has proven extremely productive. Why has this generation, born primarily between 1959 and 1967, been so incredibly successful? This article examines the contextual factors that may have contributed to the incredible success of this generation. This ranges from the policies and circumstances that affected their births, and the state of the cultural field at the time they reached adulthood. Personal experience narratives, autobiographies, and scholarly studies then reveal how this generation was able to access the intellectual field. Finally, I briefly discuss how the Amdo Tibetan intellectual field compares with other Tibetan and ethnic experiences in the People’s Republic of China.  相似文献   
9.
In this article, we introduce tempered Mittag-Leffler Lévy processes (TMLLP). TMLLP is represented as tempered stable subordinator delayed by a gamma process. Its probability density function and Lévy density are obtained in terms of infinite series and Mittag-Leffler function, respectively. Asymptotic forms of the tails and moments are given. A step-by-step procedure of the parameters estimation and simulation of sample paths is given. We also provide main results available for Mittag-Leffler Lévy processes (MLLP) and some extensions which are not available in a collective way in a single article. Our results generalize and complement the results available on Mittag-Leffler distribution and MLLP in several directions. Further, the asymptotic forms of the moments of the first-exit times of the TMLLP are also discussed.  相似文献   
10.
This paper proposes a probabilistic frontier regression model for binary type output data in a production process setup. We consider one of the two categories of outputs as ‘selected’ category and the reduction in probability of falling in this category is attributed to the reduction in technical efficiency (TE) of the decision-making unit. An efficiency measure is proposed to determine the deviations of individual units from the probabilistic frontier. Simulation results show that the average estimated TE component is close to its true value. An application of the proposed method to the data related to the Indian public sector banking system is provided where the output variable is the indicator of level of non-performing assets. Individual TE is obtained for each of the banks under consideration. Among the public sector banks, Andhra bank is found to be the most efficient, whereas the United Bank of India is the least.  相似文献   
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