Fuel consumption for various driving styles in conventional and hybrid electric vehicles: Integrating driving cycle predictions with fuel consumption optimization*

Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.     

基于平价上网的海上风电可靠性研究

海上风电是最具规模化开发价值的可再生能源,预计2020年我国累计装机容量突破8.5GW。海上风电的运维成本在度电成本占比25%～40%。2019年起国家推行风电平价上网,对海上风电的发展带来深刻影响。通过海上风电度电成本分析,建立成本-效益模型。研究发现,风电设备的可靠性、可利用率决定了运维成本和度电成本的水平。基于成本-效益模型测算某海上风电项目的度电成本,风机设备可利用率为97.15%时,运维成本下降26.88%,度电成本最低,为0.575 2元/kW·h。     

A cost-effectiveness analysis of revaccination and catch-up strategies with the 23-valent pneumococcal polysaccharide vaccine (PPV23) in older adults in Japan

Objective: In Japan, the National Immunization Program (NIP) includes PPV23 as the primary vaccination for adults and catch-up cohorts. The Japanese Association for Infectious Diseases recommends revaccination for older adults who received primary vaccination ≥5 years earlier. The cost-effectiveness of adding revaccination and/or continuing catch-up vaccination in the NIP was evaluated from the public payer perspective in Japan.

Methods: The Markov model included five health states: no pneumococcal disease, invasive pneumococcal diseases (IPD), non-bacteremic pneumococcal pneumonia (NBPP), post-meningitis sequelae, and death. Cohorts of adults aged 65–95 were followed until age 100 or death: 2014 cohort (aged 65–95, vaccinated: 2014); 2019 cohort (aged 65: 2019); and 2019 catch-up cohort (aged 70–100: 2019, unvaccinated: 2014). Strategies included: (1) vaccinate 2014 and 2019 cohorts; (2) vaccinate 2014 and 2019 cohorts and revaccinate both; (3) strategy 1 and vaccinate 2019 catch-up cohort; (4) strategy 2 and vaccinate 2019 catch-up cohort; and (5) strategy 4 and revaccinate 2019 catch-up cohort. Parameters were retrieved from global and Japanese sources, costs and QALYs discounted at 2%, and incremental cost-effectiveness ratios (ICERs) estimated.

Results: Strategy 1 had the highest number of IPD and NBPP cases, and strategy 5 the lowest. Strategies 3–5 dominated strategy 1 and strategy 2 was cost-effective compared to strategy 1 (ICER: ¥1,622,153 per QALY gained). At a willingness-to-pay threshold of ¥5 million per QALY gained, strategy 2 was cost-effective and strategies 3–5 were cost-saving compared to strategy 1.

Conclusions: Strategies including revaccination, catch-up, or both were cost-effective or cost-saving in comparison to no revaccination and no catch-up. Results can inform future vaccine policies and programs in Japan.     

广义空间调制系统的正则化OMP检测算法

在广义空间调制（GSM）系统中，最大似然（ML）检测可以取得最优的检测性能，然而其计算复杂度随激活天线数的增加急剧增长。针对这一问题，提出了一种基于稀疏重构理论的低复杂度检测算法——正则化正交匹配追踪（ROMP）算法。该算法首先根据信道矩阵和当前残差的内积选取多个候选激活天线索引，接着对候选天线索引按正则化标准进行可靠性验证，剔除错误索引，缩小信号的搜索空间，最后通过求解最小二乘问题估计信号。仿真结果表明，与经典的正交匹配追踪（OMP）算法相比，所提算法以少许复杂度的增加为代价极大提升了检测性能，能够在检测性能与复杂度之间取得更好的折中。     

Risk assessment for public–private partnership projects: using a fuzzy analytic hierarchical process method and expert opinion in China

Public–private partnerships (PPP) have been widely used in China to procure public facilities and services. Complicated problems in PPP projects in China arise because of a variety of risk factors. A proper risk assessment model is needed to identify risks and provide risk response strategies for future Chinese PPP projects. The fuzzy analytic hierarchy process (F-AHP) method provides the ability to solve complex risk assessment of PPP projects. Current risk assessment models are limited to PPP projects in specific countries and do not consider unique risks in China, especially political, economic, social, and legal risks. This paper designed a risk evaluation index system for PPP projects based on the Delphi expert investigation method, and then established an optimized risk evaluation model for PPP projects in China using the F-AHP method. The risks identified are confirmed by interviewing experts from Chinese local government departments, private enterprise, third-party intermediary consulting and regulatory agencies, and academic organizations. The results show that the risks that ranked among the top ten are closely related to China’s political and economic policies and relationships among stakeholders. It can be concluded that government authorities play a critical role in providing a favorable political, social, and economic environment and an effective institutional framework for PPP projects. Furthermore, it is also important to deal with relationships among stakeholders based on the public–private ‘win–win’ principle. This study provides risk response strategies, addressing key issues from eight aspects: an impeccable legal and regulatory framework; a central coordinating and regulating PPP authority; supportive governmental authorities; institutional capacity-building; favorable economic conditions and viability; community, partner, and moral accountability; clear division of responsibilities through contracts; and effective advisory management. These effective measures may be useful in reducing the adverse effects of risk for PPP projects in China.     

Effects of individual resources and team-member exchange on service quality

While workplace resources are generally viewed as positively affecting performance, some studies indicate that not all resources increase performance. This study addresses the controversial disparate effects of workplace resources on performance by exploring functionally classified workplace resources in self-managing service teams and their relative impacts on team service quality. Considering membership dynamics and consequences between members, a field experiment was conducted in a cafeteria, with data collected through a working diary for workplace resources and a customer survey to evaluate service quality. Results suggest that efficacy-resources in self-managing teams should be controlled with caution as they may adversely affect team service quality. Supporting the person–situation interactionism perspective, workplace resources interact dynamically with individual employees and with situations. Esteem-resources were found to increase team service quality, while team-member exchange not only improved team service quality but also moderated the impact of esteem-resources on team service quality.     

Quality of Corporate Social Responsibility Disclosure and Cost of Equity Capital: Lessons from China

This article explores the relationship between the quality of corporate social responsibility (CSR) disclosure and the cost of equity capital by analyzing the financial data and CSR reports of A-share listed firms in China from 2008 to 2014. The quality of the CSR disclosure is shown to be negatively related to the cost of equity capital of the listed firms. This negative correlation proves to be more prominent among firms of environmentally sensitive industries. Taking the ownership of the listed firms into consideration, it is further confirmed that the negative relationship between the CSR disclosure and the cost of equity capital is of higher significance for state-owned enterprises. Our findings also empirically demonstrate that the quality of CSR disclosure is more negatively related to the cost of equity capital among the large listed firms than the smaller ones.     

利用信道状态信息的室内定位技术

多径效应导致基于信号接收强度（RSSI）的室内定位方法精度不高，采用更细粒度的物理层信道状态信息（CSI）可以区分不同路径，提高定位精度。在已有基于CSI室内定位方法的基础上，通过改进对数距离路径损耗模型，得到CSI与传输距离的关系，并结合目标位置所测得的CSI值回归出目标与发射端的距离，最后通过三边定位法预测出目标的位置坐标。实验表明，相比基于RSSI的定位方法以及已有的基于CSI的定位方法，所提方法2 m以内的误差概率提高了将近40%和20%，有效提高了定位精度。     

The distinct contribution of investment promotion agencies’ branch offices in bringing Chinese multinationals to Europe

This study uncovers the distinct contribution of investment promotion agencies’ (IPAs) overseas branch offices in advancing and even creating foreign direct investment. It offers a novel categorisation of IPAs depending on location and headquarter/branch status, and conceptually connects the known functions of IPAs with the advantages set out by the OLI paradigm. Empirical examination of longitudinal data from 29 European IPAs finds that the activities of their branches in China instilled greater awareness and confidence in Chinese multinational enterprises about their ownership- and European location-specific advantages. This contribution of IPA branches is especially salient in emerging economies with newcomer investors.     

茭簰考释--兼及江汉平原湖区人水关系

明清时期长江中游地区地方文献记载的茭簰,并非漂浮种植性质的葑田,而是漂浮居住性质的水上居家设施。“随波上下”且“不时迁移”是其基本特性,实质是借水之力以避水之害,乃湖区居民应对洪涝灾害的居住创举。茭簰不同于为众熟知的舟船,亦有别于水上航行的排筏,茭簰居民并非渔民,而是备有“种莳牲畜”的农民。茭簰与葑田,虽然一耕一居,却具有共同的指向。茭簰是湖区农家适应环境变化,根据生产生活需要而做出的相对选择,堪称湖区居民趋利避害、协调人水关系的代表性举措。