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Effect of the new maternity insurance scheme on medical expenditures for caesarean delivery in Wuxi,

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《医学前沿（英文）》 2016年第10卷第4期页码 473-480 doi: 10.1007/s11684-016-0479-

摘要：

Aiming to control rising medical expenditures and help improve China’s healthcare systems, this study examined whether a cap-based medical insurance scheme with shared financial interest between the insurance and healthcare providers is effective in containing hospitals’ C-section medical expenditures. We used 6547 caesarean delivery case records from a teaching tertiary-level general public hospital located in Wuxi, China (2004–2013), and used the Chow test to investigate the possibility of significant variation in mean medical expenditures for caesarean deliveries pre- and post-reform. We also used paired sample t-tests and linear regression models to compare the mean medical expenditures between insured and uninsured women undergoing caesarean delivery during the post-reform period. After the scheme’s implementation, medical expenditures for caesarean deliveries declined and the medical expenditures of women covered by the scheme were significantly lower than those of uninsured patients. These findings indicated the scheme’s effectiveness in minimizing caesarean delivery expenditures. The cap-based medical insurance scheme with shared financial interest between insurance and healthcare providers would likely steer healthcare providers’ behaviors in a more cost-effective direction.

关键词： maternity insurance scheme financial incentive caesarean delivery medical expenditure China

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Integration of current identity-based district-varied health insurance schemes in China: implications

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《医学前沿（英文）》 2012年第6卷第1期页码 79-84 doi: 10.1007/s11684-012-0179-5

摘要：

With China’s great efforts to improve public health insurance, clear progress has been achieved toward the ambitious full health insurance coverage strategy for all. The current health insurance schemes in China fall into three categories: urban employee basic health insurance scheme, urban resident scheme, and new rural cooperative medical system. Despite their phasic success, these substantially identity-based, district-varied health insurance schemes have separate operation mechanisms, various administrative institutions, and consequently poor connections. On the other hand, the establishment and implementation of various health insurance schemes provide the preconditioning of more sophisticated social health insurance schemes, the increase in the income of urban and rural people, and the great importance attached by the government. Moreover, the reform of the “Hukou” (household register) system provides economical, official, and institutional bases. Therefore, the establishment of an urban-rural integrated, citizen-based, and nationwide-universal health insurance scheme by the government is critically important to attain equality and national connection. Accordingly, the differences between urban and rural areas should be minimized. In addition, the current schemes, administrative institutions, and networks should be integrated and interconnected. Moreover, more expenditure on health insurance might be essential for the integration despite the settings of global financial crisis. Regardless of the possible challenges in implementation, the proposed new scheme is promising and may be applied in the near future for the benefit of the Chinese people and global health.

关键词： health insurance urban employee basic health insurance scheme urban-resident scheme new rural cooperative medical system

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Social insurance for occupational diseases

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《医学前沿（英文）》 2012年第6卷第2期页码 221-223 doi: 10.1007/s11684-012-0187-5

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施工导流工程风险的保险费用厘定方法研究

陈志鼎,胡志根

《中国工程科学》 2011年第13卷第4期页码 106-112

摘要：

在分析导流工程风险因素、综合风险率和工程保险期限的基础上，研究导流工程失效后淹没基坑造成损失的次数及其分布规律，提出导流系统失效后的总损失服从非齐次复合Poisson过程，建立基于导流工程保险损失的聚合风险模型，给出施工导流工程保险费用的厘定方法及其数学表达，为水利水电工程保险费的厘定提供理论方法。

关键词：导流风险工程保险保险费非齐次复合Poisson过程

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Z-scheme CdS/WO on a carbon cloth enabling effective hydrogen evolution

《能源前沿（英文）》 2021年第15卷第3期页码 678-686 doi: 10.1007/s11708-021-0768-6

摘要： Photocatalytic water splitting for hydrogen (H₂) generation is a potential strategy to solve the problem of energy crisis and environmental deterioration. However, powder-like photocatalysts are difficult to recycle, and the agglomeration of particles would affect the photocatalytic activity. Herein, a direct Z-scheme CdS/WO₃ composite photocatalyst was fabricated based on carbon cloth through a two-step process. With the support of carbon cloth, photocatalysts tend to grow uniformly for further applications. The experimental results showed that the H₂ yield of adding one piece of CdS/WO₃ composite material was 17.28 μmol/h, which was 5.5 times as compared to that of pure CdS-loaded carbon cloth material. A cycle experiment was conducted to verify the stability of the as-prepared material and the result demonstrated that the H₂ generation performance of CdS/WO₃ decreased slightly after 3 cycles. This work provides new ideas for the development of recyclable photocatalysts and has a positive significance for practical applications.

关键词： photocatalysis CdS/WO₃ carbon cloth Z-scheme hydrogen evolution

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Emergency design framework: a satellite preliminary scheme design

TENG Hongfei, WANG Yishou, ZHANG Bao

《机械工程前沿（英文）》 2007年第2卷第2期页码 184-192 doi: 10.1007/s11465-007-0031-9

摘要： The emergency design of mechanical products or equipment (such as a satellite) is significant for disaster relief when the natural disasters occur. Most of us are unaware about the little information that is available in literature about emergency designs. Against the background of the preliminary scheme design of satellite payloads, emergency design was studied in the case of natural disasters. We presented some definitions about emergency design. Then, we proposed the basic ideas of how to realize the emergency design. These ideas were inspired by two aspects: 1) the evolutionary algorithms, the agent, the human-computer cooperation, and the collaborative design theory; 2) the emergency behaviors in ant colonies. Following the ideas, first we constructed the human computer cooperation agents (hereinafter called the HC-Agents) that combine the human intelligence with evolutionary algorithms. These HC-Agents had specific features like the division of labor in the ant colony. Second, we developed the multiagents cooperative design system on the basis of a hybrid P2P (peer-to-peer) model. Therefore, the emergency design system has shown some capabilities, such as anti-interference, adaptation, and rapid response.

关键词： significant intelligence P2P hereinafter computer cooperation

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A lightweight authentication scheme with user untraceability

Kuo-Hui YEH

《信息与电子工程前沿（英文）》 2015年第16卷第4期页码 259-271 doi: 10.1631/FITEE.1400232

摘要： With the rapid growth of electronic commerce and associated demands on variants of Internet based applications, application systems providing network resources and business services are in high demand around the world. To guarantee robust security and computational efficiency for service retrieval, a variety of authentication schemes have been proposed. However, most of these schemes have been found to be lacking when subject to a formal security analysis. Recently, Chang (2014) introduced a formally provable secure authentication protocol with the property of user-untraceability. Unfortunately, based on our analysis, the proposed scheme fails to provide the property of user-untraceability as claimed, and is insecure against user impersonation attack, server counterfeit attack, and man-in-the-middle attack. In this paper, we demonstrate the details of these malicious attacks. A security enhanced authentication scheme is proposed to eliminate all identified weaknesses.

关键词： Authentication Privacy Security Smart card Untraceability

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ZnFe₂O₄/BiVO₄ Z-scheme heterojunction for efficient visible-light photocatalytic

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1728-1740 doi: 10.1007/s11705-023-2322-z

摘要： A novel Z-scheme ZnFe₂O₄/BiVO₄ heterojunction photocatalyst was successfully synthesized using a convenient solvothermal method and applied in the visible light photocatalytic degradation of ciprofloxacin, which is a typical antibiotic contaminant in wastewater. The heterostructure of as-synthesized catalysts was confirmed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy characterizations. Compared with the single-phase counterparts, ZnFe₂O₄/BiVO₄ demonstrated considerably enhanced photogenerated charge separation efficiencies because of the Z-scheme transfer mechanism of electrons between the composite photocatalysts. Consequently, the 30% ZnFe₂O₄/BiVO₄ catalyst afforded a degradation rate of up to 97% of 20 mg/L ciprofloxacin under 30 min of visible light irradiation with a total organic carbon removal rate of 50%, which is an excellent activity compared with ever reported BiVO₄-based catalysts. In addition, the liquid chromatography-mass spectrometry and quantitative structure-activity relationships model analyses demonstrated that the toxicity of the intermediates was lower than that of the parent ciprofloxacin. Moreover, the as-synthesized ZnFe₂O₄/BiVO₄ heterojunctions were quite stable and could be reused at least four times. This study thus provides a promising Z-scheme heterojunction photocatalyst for the efficient removal and detoxication of antibiotic pollutants from wastewater.

关键词： ZnFe₂O₄/BiVO₄ Z-scheme heterojunction photocatalytic degradation ciprofloxacin

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Extended model predictive control scheme for smooth path following of autonomous vehicles

《机械工程前沿（英文）》 2022年第17卷第1期页码 4-4 doi: 10.1007/s11465-021-0660-4

摘要： This paper presents an extended model predictive control (MPC) scheme for implementing optimal path following of autonomous vehicles, which has multiple constraints and an integrated model of vehicle and road dynamics. Road curvature and inclination factors are used in the construction of the vehicle dynamic model to describe its lateral and roll dynamics accurately. Sideslip, rollover, and vehicle envelopes are used as multiple constraints in the MPC controller formulation. Then, an extended MPC method solved by differential evolution optimization algorithm is proposed to realize optimal smooth path following based on driving path features. Finally, simulation and real experiments are carried out to evaluate the feasibility and the effectiveness of the extended MPC scheme. Results indicate that the proposed method can obtain the smooth transition to follow the optimal drivable path and satisfy the lateral dynamic stability and environmental constraints, which can improve the path following quality for better ride comfort and road availability of autonomous vehicles.

关键词： autonomous vehicles vehicle dynamic modeling model predictive control path following optimization algorithm

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Determination of the scheme of precision grinding compensation on the radome

GUO Dongming, LIU Minjing, ZHANG Chunbo, SHENG Xianjun, SUN Yuwen

《机械工程前沿（英文）》 2007年第2卷第3期页码 263-266 doi: 10.1007/s11465-007-0045-3

摘要： The radome, which is often used to house airborne scanning radar antennas, causes a large boresight error and boresight error slope of the radar antenna. One way to decrease the boresight error induced by the radome is to modify its geometric thickness. Determining the grinding scheme from the boresight error performance is the most important problem to be solved. A typical inverse problem about electromagnetic fields is solving the precise grinding compensation area and allowance according to the antenna aperture distribution and the radome s boresight error performance, which could hardly be solved by a purely mathematical method. An effective approach combining theoretical analysis and mathematical calculations with experimental measurement is presented in this paper to determine the grinding area and allowance for compensating the boresight error performance of the radome. By comparing the calculated and measured data of the boresight error and the boresight error slope before and after grinding, it is shown that this method is simple and practical and can be used for many kinds of radomes.

关键词： mathematical effective approach experimental measurement antenna electromagnetic

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Investigation on a mitigation scheme to resist the progressive collapse of reinforced concrete buildings

Iman TABAEYE IZADI, Abdolrasoul RANJBARAN

《结构与土木工程前沿（英文）》 2012年第6卷第4期页码 421-430 doi: 10.1007/s11709-012-0181-7

摘要： This study presents the investigation of the approach which was presented by Thaer M. Saeed Alrudaini to provide the alternate load path to redistribute residual loads and preventing from the potential progressive collapse of RC buildings. It was proposed to transfer the residual loads upwards above the failed column of RC buildings by vertical cables hanged at the top to a hat steel braced frame seated on top of the building which in turn redistributes the residual loads to the adjacent columns. In this study a ten-storey regular structural building has been considered to investigate progressive collapse potential. Structural design is based on ACI 318-08 concrete building code for special RC frames and the nonlinear dynamic analysis is carried out using SAP2000 software, following UFC4-023-03 document. Nine independent failure scenarios are adopted in the investigation, including six external removal cases in different floors and three removal cases in the first floor. A new detail is proposed by using barrel and wedge to improve residual forces transfer to the cables after removal of the columns. Simulation results show that progressive collapse of building that resulted from potential failure of columns located in floors can be efficiently resisted by using this method.

关键词： prevent progressive collapse alternate load path reinforced concrete buildings nonlinear dynamic retrofitting cable steel hat braced frame barrel and wedge

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燕山石化公司乙烯装置66×10⁴t/a扩能改造方案的研究与决策

曹湘洪

《中国工程科学》 2003年第5卷第11期页码 34-46

摘要：

燕山石化公司30×10⁴t/a乙烯装置1994年完成第一次扩能至45×10⁴t/a的改造后，仍存在原料灵活性差、能耗高、与同期建设的乙烯装置比规模偏小等问题。以全面提高技术水平、降低能耗、增加原料灵活性、尽可能扩大生产能力为目标，充分考虑方案的可实施性、实施时的安全性、实施后的可操作性及方案的先进性和经济性，对装置技术改造的方案进行了比选研究。经改造，实现了生产能力扩大到66×10⁴t/a的目标，实际可达71×10⁴t/a，装置能耗明显下降，石脑油、轻柴油、重柴油、加氢裂化尾油均可作为乙烯原料。在世界上，首次在乙烯装置中采用混合冷剂制冷技术和碳三催化精馏加氢技术并获得成功，对世界乙烯工业技术进步有推动作用。

关键词：乙烯装置扩能方案研究

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Temporal dimension and water quality control in an emission trading scheme based on water environmental

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 119-129 doi: 10.1007/s11783-011-0272-z

摘要： Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.

关键词： emission trading water functional zone water quality control

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Load shedding scheme for an interconnected hydro-thermal hybrid system with SMES

D. TYAGI, Ashwani KUMAR, Saurabh CHANANA

《能源前沿（英文）》 2012年第6卷第3期页码 227-236 doi: 10.1007/s11708-012-0198-6

摘要： The frequency of the power system varies based on the load pattern of the consumers. With continuous increase in the load, the frequency of the system keeps decreasing and may reach its minimum allowable limits. Further increase in the load will result in more frequency drop leading to the need of load shedding, if excess generation is not available to cater the need. This paper proposed a methodology in a hybrid thermal-hydro system for finding the required amount of load to be shed for setting the frequency of the system within its minimum allowable limits. The load shedding steps were obtained based on the rate of change of frequency with the increase in the load in both areas. The impact of superconducting magnetic energy storage (SMES) was obtained on load shedding scheme. The comparison of the results was presented on the two-area system.

关键词： critical load frequency response load shedding multi-area system rate of change of frequency superconducting magnetic energy storage (SMES) device

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A control scheme with performance prediction for a PV fed water pumping system

Ramesh K GOVINDARAJAN,Pankaj Raghav PARTHASARATHY,Saravana Ilango GANESAN

《能源前沿（英文）》 2014年第8卷第4期页码 480-489 doi: 10.1007/s11708-014-0334-6

摘要： This paper focuses on modeling and performance predetermination of a photovoltaic (PV) system with a boost converter fed permanent magnet direct current (PMDC) motor-centrifugal pump load, taking the converter losses into account. Sizing is done based on the maximum power generated by the PV array at the average irradiation. Hence optimum sizing of the PV array for the given irradiation at the geographical location of interest is obtained using the predetermined values. The analysis presented here involves systems employing maximum power point tracking (MPPT) as they are more efficient than directly coupled systems. However, the voltage and power of the motor might rise above rated values for irradiations greater than the average when employing MPPT, hence a control scheme has been proposed to protect the PMDC motor from being damaged during these conditions. This control scheme appropriately chooses the optimum operating point of the system, ensuring long-term sustained operation. The numerical simulation of the system is performed in Matlab/Simulink and is validated with experimental results obtained from a 180 V, 0.5 hp PMDC motor coupled to a centrifugal pump. The operation of the system with the proposed control scheme is verified by varying the irradiation levels and the relevant results are presented.

关键词： photovoltaic system boost converter maximum power point tracking (MPPT) DC permanent-magnet motor centrifugal pump