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131.
质量体系与HSE管理体系一体化初探   总被引:1,自引:0,他引:1  
从分析ISO900标准与HSE管理标准的相同点和不同点入手,从管理学的角度探讨了质量体系与HSE管理体系相结合的可能性与必要性,探讨了企业实施两个体系一体化的措施。指出,建立一个能同时满足了ISO9000标准要求和HSE管理标准要求的综合体系,可以明显地提高企业管理效益、降低体系运行费用。  相似文献   
132.
Internet users have suffered collateral damage in tussles over paid peering between large ISPs and large content providers. Paid peering is a relationship where two networks exchange traffic with payment, which provides direct access to each other’s customers without having to pay a third party to carry that traffic for them. The issue will arise again when the United States Federal Communications Commission (FCC) considers a new net neutrality order.We first consider the effect of paid peering on broadband prices. We adopt a two-sided market model in which an ISP maximizes profit by setting broadband prices and a paid peering price. We analytically derive the profit-maximizing prices, and show that they satisfy a generalization of the well-known Lerner rule. Our result shows that paid peering fees reduce the premium plan price, increase the video streaming price and the total price for premium tier customers who subscribe to video streaming services; however, the ISP passes on to its customers only a portion of the revenue from paid peering. ISP profit increases but video streaming profit decreases as an ISP moves from settlement-free peering to paid peering price.We next consider the effect of paid peering on consumer surplus. We find that consumer surplus is a uni-modal function of the paid peering fee. The paid peering fee that maximizes consumer surplus depends on elasticities of demand for broadband and for video streaming. However, consumer surplus is maximized when paid peering fees are significantly lower than those that maximize ISP profit. However, it does not follow that settlement-free peering is always the policy that maximizes consumer surplus. The peering price depends critically on the incremental ISP cost per video streaming subscriber; at different costs, it can be negative, zero, or positive.  相似文献   
133.
几内亚马西铁路是服务于西芒杜矿区企业铁矿石产品的铁路外运的重要基础设施,其限制坡度的确定是影响线路走向的主要技术标准,同时对工程投资、建设规模、运输能力、运营效果及行车安全性等至关重要。在阐述马西铁路现状的基础上,对马西铁路限制坡度取值范围进行估算,提出6‰/9‰均衡坡方案、6‰/13‰均衡坡方案、9‰/13‰均衡坡方案3种限制坡度方案,分析影响马西铁路限制坡度选择的主要因素,并通过车流特点、沿线地形地貌、机车类型、牵引质量、工程适应性及投资等方面对不同坡度方案进行分析比选,在满足研究年度运输需求前提下采用综合费用现值法,推荐采用6‰/9‰分方向选择限制坡度的均衡坡方案,研究成果对国内外货运铁路限制坡度的选择具有一定的指导和借鉴意义。  相似文献   
134.
This study proposes and tests a conceptual model that investigates the mediating effect of safety motivation linking psychological contract of safety (PCS) as manifested by employer obligations of safety and employee obligations of safety to safety violations and safety creative performance (SCP). Data were collected from a sample of flight attendants with two weeks time lag in Iran. Underpinned by social exchange theory, the results of structural equation modeling revealed that safety motivation fully mediates the simultaneous effects of PCS indicators on safety violations and SCP. Specifically, indicators of PCS jointly enhance safety motivation. In turn, safety motivation reduces safety violations, while enhancing SCP. Theoretical and practical implications evoked from the results advance existing knowledge of organizationally social interactions in promoting safety and the motivational mechanism through which PCS predicts employees' safety performance outcomes.  相似文献   
135.
The approach, descent, and climb phases of flights in terminal maneuvering areas (TMAs) are some of the critical parts of a flight in which more than half of accidents happen. For an ANSP (Air Navigation Service Provider), to fulfill the responsibility with a high-quality service degree while maintaining safety, these difficult areas should be designed carefully and equipped with the most efficient procedures. Point merge system (PMS), which is defined as a systemized method for sequencing arrival flows, is launched in Istanbul's new TMA (LTFM TMA) being designed by DHMI (Devlet Hava Meydanları Isletmesi) to improve safety and efficiency. In this paper, the airspace complexity is based on adjusted density and structural index, and safety indicators. To investigate the effects of the radical changes made in re-organized LTFM TMA on the safety issue in comparison with the previous terminal maneuvering area, LTBA TMA, six months' data consisting of 75215 arrival and departure flights are used. Results reflect that the LTFM TMA, one of the world's busiest terminal airspaces, has statistically significantly lower scores in terms of conflict numbers per aircraft, complexity metrics, adjusted density, the hour of interactions, and flight hours than LTBA TMA. Lastly, there exists no longer a significant relationship between conflict types and complexity after launching the new design and structure.  相似文献   
136.
This paper investigates the quantile-based spillover effects among 17 stock markets from January 1993 to January 2022, utilizing a quantile approach based on the variance decomposition of a quantile vector autoregression (QVAR) model. Compared with the traditional mean-based spillover measures, this new quantile approach allows for a nuanced investigation of spillovers at every quantile and capture spillovers under extreme events. The results show that: (1) the total spillover is high and exhibits strong time-varying characteristics, and the tail spillover is higher and more complex in scale and direction; (2) the spillover at each quantile level shows an upward trend, especially during the 2008 crisis and the COVID-19 epidemic; (3) developed countries (or regions) are the net exporters of stock market spillovers, while the developing countries are the net importers; and (4) the 17 stock markets constitute different local financial networks, which may be related to economic conditions and geographical location.  相似文献   
137.
Pedestrian group detection is a challenging but significant issue in pedestrian flow control and public safety management. To address the issue that most conventional pedestrian grouping models (PGMs) can only identify a pedestrian group at a limited distance of less than 2 m, this study extended the pedestrian distance constraint of conventional PGMs with a reconstruction of the normal group detection criterion and development of a novel group detection criterion suitable for long-span space. To measure the movement behavior similarity with normal distance, five necessary constraints: velocity difference, moving direction offset, distance limitation, distance fluctuation, and group-keeping duration were studied quantitatively to form the criterion to detect normal groups. Meanwhile, a long-span group detection criterion was proposed with extended distance and direction consistency constraints. Therefore, this study proposed an improved PGM that considers long-span spaces (PGMLS). In the PGMLS workflow, the MMTrack algorithm was used to obtain pedestrian trajectories. A difference measurement method based on sequential pattern analysis (SPA) was adopted to analyze the velocity similarity of pedestrians. To validate the proposed grouping model, experiments based on pedestrian movement videos in the exit hall of the Shanghai Hongqiao International Airport were conducted. The results indicate that the proposed model can detect both normal and widely separated pedestrian groups, with a long span range of 2–12 m.  相似文献   
138.
This study compares the information content of funds from operations (FFO) and net income (NI) in the real estate investment trust (REIT) industry. We find that models using FFO explain more of the variance in cumulative abnormal returns around earnings announcement dates than models using NI do. We also find that the information content of FFO differs across REITs of different sizes. FFO does not provide useful information to investors in the case of large REITs. Finally, we show that the gain or loss from sales of property is relevant to valuing large REITs.  相似文献   
139.
Managing safety and health matters require comprehensive policy intervention to change the existing culture in the ground handling operations and reducing the safety performance outcomes. This study aims to investigate the relationship between safety culture and safety performance outcome with voluntary policy intervention as the moderating effect of the relationship. The study employed a quantitative method through a survey instrument, which was participated by 423 ground handling workers from six international airports in Malaysia. The results indicated seven hypotheses in direct relationships have positive association between safety culture and safety performance construct. While for moderator relationships, there were five hypotheses found to be statistically significant and supported. The presence of voluntary policy interventions were found to be beneficial or detrimental elements for the insignificant relationships of the study. The ground handling organisation is expected to utilise these results by strengthening their organisation safety culture and prioritise safety and health matters over demand and cost.  相似文献   
140.
标准化建设是提高铁路企业效率和安全管控能力的重要途径。兰州局集团公司车务系统以标准化为主线,以实现人的行为安全可控为目标,遵循体系建设系统性、充分性、适宜性的要求,坚持体系化、标准化、闭环管理、流程再造的设计原则,从标准体系及标准评价体系、标准化车间、标准化生产指挥中心和智能行车系统等方面,对车务系统安全标准化体系功能进行设计,为构建管理规范、标准统一、保障有力的车务系统安全标准化体系提供支撑。  相似文献   
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