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1.
双层规划研究的是两个各具有目标函数的决策者之间按有序的和非合作方式进行的相互作用,上层决策者优先作出决策,下层决策者在上层决策信息下按自己的利益作出反应,由于一方的行为影响另一方的策略选择和目标的实现,并且任何一方又不能完全控制另一方的选择行为,因此上层决策者要根据下层的反应做出符合自身利益的最终决策。而公交车辆配置正符合双层规划模型的思想,所以本论文采用双层规划模型来描述车辆配置与客流量之间的相互作用,从而优化公交线网的车辆配置。 相似文献
2.
杨学武 《广东微量元素科学》2017,24(5)
突发公共卫生事件一直是政府组织十分关注的问题。当前,在公共卫生事件出现高频率的发生几率后,健康教育工作已占据着越来越重要的地位。从宏观角度来说,突发公共卫生事件是一个涵盖范围十分广泛的事件内容,其事件包含了多个可预测与不可预测的突发状况,也包含了任何地点、任何社会群体以及任何事件当中,因此在健康教育上,需从宏观范围进行全面计划,以系统式方式对各个突发公共卫生事件做出针对性教育,且对教育内容作出可行性评估,切实保障健康教育对突发公共卫生事件有一定的作用及影响力。对此,为进一步探讨该话题,针对突发公共卫生事件健康教育基本策略展开详细探讨。 相似文献
3.
随着社会经济的发展及人们环保意识的不断增强,公共交通事业的发展及其投资力度不断加大,公共交通在给人们带来方便的同时也在带动着经济的发展.通过扩展的生产函数模型,采用普通最小二乘方法对2003-2012年间的公共交通数据进行估计分析,并找出有异常值的样本点,然后利用稳健MM估计方法进行估计,结果表明公共交通变量对经济的影响具有正相关作用. 相似文献
4.
建立了不符合度、失望度、不满意度等概念,将公务员招聘问题转化为求不满意度总和最小的0—1规划模型,很好地解决了在不考虑和考虑应聘人员意愿的两种情形下公务员招聘的问题.充分体现了录取的公平公正性和对人才的充分利用. 相似文献
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Solar energy is considered clean energy, and its use is predicted to increase in the near future. Most installed units today are crystalline solar cells, but the field is in constant development, and when the first dye sensitized solar cell was published by Grätzel and O'Reagan a new, third-generation, solar power was born. Highly toxic metals are used to produce the photovoltaic units today, and with the predicted increase in solar cell installation, the human health hazards of these panels could become an issue. Additionally, many of these materials are used in their nanoform, which is associated with an additional risk. In this article, we discuss the technology behind the third-generation solar cells with its valuable use of nanotechnology as well as the possible health hazard when such nanomaterials are used in solar power units. We will show that the main exposure will occur either during the development and production phases or at the end-of-life stage of the solar cells, where toxic material can leach into landfills, and subsequently into the environment and impact the ecosystem directly, or humans indirectly through edible plants or drinking water. 相似文献
7.
There exists a natural trade-off in public key encryption (PKE) schemes based on ring learning with errors (RLWE), namely: we would like a wider error distribution to increase the security, but it comes at the cost of an increased decryption failure rate (DFR). A straightforward solution to this problem is the error-correcting code, which is commonly used in communication systems and already appears in some RLWE-based proposals. However, applying error-correcting codes to those cryptographic schemes is far from simply installing an add-on. Firstly, the residue error term derived by decryption has correlated coefficients, whereas most prevalent error-correcting codes with remarkable error tolerance assume the channel noise to be independent and memoryless. This explains why only simple error-correcting methods are used in existing RLWE-based PKE schemes. Secondly, the residue error term has correlated coefficients leaving accurate DFR estimation challenging even for uncoded plaintext. It can be found in the literature that a tighter DFR estimation can effectively create a DFR margin. Thirdly, most error-correcting codes are not well designed for safety considerations, e.g., syndrome decoding has a nonconstant time nature. A code good at error correcting might be weak under a variety of attacks. In this work, we propose a polar coding scheme for RLWE-based PKE. A relaxed “independence” assumption is used to derive an uncorrelated residue noise term, and a wireless communication strategy, outage, is used to construct polar codes. Furthermore, some knowledge about the residue noise is exploited to improve the decoding performance. With the parameterization of NewHope Round 2, the proposed scheme creates a considerable DRF margin, which gives a competitive security improvement compared to state-of-the-art benchmarks. Specifically, the security is improved by , while a DFR of is achieved a for code rate pf 0.25, 12,289, and binomial parameter . Moreover, polar encoding and decoding have a quasilinear complexity and intrinsically support constant-time implementations. 相似文献
8.
Essential oils (EOs) have been used for centuries, and interest in these compounds has been revived in recent years. Due to their unique chemical composition as well as antimicrobial, immunostimulatory, anti-inflammatory and antioxidant properties, EOs are used in pharmacology, cosmetology and, increasingly, in animal breeding and rearing, and processing of animal raw materials. Essential oils have become a natural alternative to preservatives, taste enhancers and, most importantly, antibiotics, because the European Union banned the use of antibiotics in metaphylaxis in animal husbandry in 2006. In the animal production chain, EOs are used mainly as feed additives to improve feed palatability and increase feed intake, improve animal resistance and health status, and to prevent and treat diseases. Recent research indicates that EOs can also be applied to sanitize poultry houses, and they can be used as biopesticides in organic farming. Essential oils effectively preserve meat and milk and, consequently, improve the safety, hygiene and quality of animal-based foods. Novel technologies such as encapsulation may increase the bioavailability of EOs and their application in the production of food and feed additives. 相似文献
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Koehler G 《Nonlinear dynamics, psychology, and life sciences》2003,7(1):99-114
Nonlinear Dynamics, Psychology, and Life Sciences - Can public policy development and implementation be improved by closely tracking and coordinating its timing with that of the regulated sector?... 相似文献