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2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

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Web-based construction equipment fleet management system: cost-effective global and local allocation

Hakob AVETISYAN, Miroslaw SKIBNIEWSKI

《工程管理前沿（英文）》 2017年第4卷第1期页码 76-83 doi: 10.15302/J-FEM-2017012

摘要： Over the last two decades, construction contractors have been gradually making more investments in construction equipment to meet their needs associated with increasing volumes of construction projects. At present, from an operational perspective, almost all contractors pay more attention to maintaining their equipment fleets in well-sustained workable conditions and having a high accessibility of the necessary equipment pieces. However, such an approach alone is not enough to maintain an efficient and sustainable business. In particular, for large-scale construction companies that operate in multiple sites in the U.S. or overseas, the problem extends to an optimal allocation of available equipment. Given the current state of the construction industry in the U.S., this problem can be solved by geographically locating equipment pieces and then wisely re-allocating them among projects. Identifying equipment pieces geographically is a relatively easy task. The difficulty arises when informed decision-making is required for equipment allocation among job sites. The actual allocation of equipment should be both economically feasible and technologically preferable. To help in informed decision-making, an optimization model is developed as a mixed integer program. This model is formed based on a previously successfully developed decision-support model for construction equipment selection. The proposed model incorporates logical strategies of supply chain management to optimally select construction equipment for any construction site while taking into account the costs, availability, and transportation-related issues as constraints. The model benefits those responsible for informed decision-making for construction equipment selection and allocation. It also benefits the owners of construction companies, owing to its cost-minimization objective.

关键词： Construction equipment Equipment assignment optimization Web-based asset management

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Analysis of cost effective pavement treatment and budget optimization for arterial roads in the city

Mbakisya ONYANGO, Saliha Ammour MERABTI, Joseph OWINO, Ignatius FOMUNUNG, Weidong WU

《结构与土木工程前沿（英文）》 2018年第12卷第3期页码 291-299 doi: 10.1007/s11709-017-0419-5

摘要：

Many transportation agencies lack sufficient funds to maintain and repair roads, which results into increased pavement maintenance cost. Pavement Management System (PMS) has demonstrated to be an essential tool for proper management of infrastructure and proper utilization of available funds. The University of Tennessee at Chattanooga utilized Micropaver software as PMS tool to conduct a pavement management analysis of principal arterials in the City of Chattanooga. The study used the City of Chattanooga pavement database to create the current and future pavement conditions. Maintenance and repair (M&R) planning analysis was also performed in order to determine the most cost-effective treatment and suggest the optimum utilization of funds for the city. An analysis of five budget scenarios was conducted for a five-year plan using the critical pavement condition index (PCI) method (ASTM D6433). Results show that the backlog elimination budget would be the best scenario because it increases the pavement condition and eliminates the backlog of major maintenance and repairs over the five-year period. The unlimited budget seems though ideal, it does not improve pavement condition. Maintaining current condition and limited budget scenarios would increase both the backlog and the total cost of maintenance and repairs over the analysis period.

关键词： PMS Micropaver pavement budget maintenance rehabilitation

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Redox flow batteries—Concepts and chemistries for cost-effective energy storage

Matthäa Verena HOLLAND-CUNZ, Faye CORDING, Jochen FRIEDL, Ulrich STIMMING

《能源前沿（英文）》 2018年第12卷第2期页码 198-224 doi: 10.1007/s11708-018-0552-4

摘要： Electrochemical energy storage is one of the few options to store the energy from intermittent renewable energy sources like wind and solar. Redox flow batteries (RFBs) are such an energy storage system, which has favorable features over other battery technologies, e.g. solid state batteries, due to their inherent safety and the independent scaling of energy and power content. However, because of their low energy-density, low power-density, and the cost of components such as redox species and membranes, commercialised RFB systems like the all-vanadium chemistry cannot make full use of the inherent advantages over other systems. In principle, there are three pathways to improve RFBs and to make them viable for large scale application: First, to employ electrolytes with higher energy density. This goal can be achieved by increasing the concentration of redox species, employing redox species that store more than one electron or by increasing the cell voltage. Second, to enhance the power output of the battery cells by using high kinetic redox species, increasing the cell voltage, implementing novel cell designs or membranes with lower resistance. The first two means reduce the electrode surface area needed to supply a certain power output, thereby bringing down costs for expensive components such as membranes. Third, to reduce the costs of single or multiple components such as redox species or membranes. To achieve these objectives it is necessary to develop new battery chemistries and cell configurations. In this review, a comparison of promising cell chemistries is focused on, be they all-liquid, slurries or hybrids combining liquid, gas and solid phases. The aim is to elucidate which redox-system is most favorable in terms of energy-density, power-density and capital cost. Besides, the choice of solvent and the selection of an inorganic or organic redox couples with the entailing consequences are discussed.

关键词： electrochemical energy storage redox flow battery vanadium

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Treatment of soybean wastewater by a wild strain Rhodobacter sphaeroides and to produce protein under natural conditions

Junguo HE, Guangming ZHANG, Haifeng LU,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 334-339 doi: 10.1007/s11783-010-0239-5

摘要： The conventional treatment method of soybean wastewater is expensive and generates waste sludge that requires further handling. Purple nonsulfur bacteria (PNSB) wastewater treatment is a clean technology and can generate single cell protein while degrading pollutants. A wild strain of PNSB, Z08, was isolated from local soil and was used to treat soybean wastewater. To develop a cost-effective process, the work was performed under natural conditions without artificial light, aeration, nutrients addition, or pH and temperature adjustment. The results showed that the wild strain Z08 could grow well under natural conditions. The growth curve showed two quick-growth periods and a turning point. The Z08 treatment of soybean wastewater was zero order reaction and COD reduction was 96% after 10 d. The major byproducts of the process were C2-C5 organic acids, predominantly butyric acid. No alcohol was found in the effluent. The initial COD/bacterial-mass ratio (F/M) had a significant effect on soybean wastewater treatment efficiency. When the initial F/M was lower than 10 mg-COD/mg-bacteria, a sufficient amount of time to achieve 90% of COD reduction was only three days. The Z08 biomass yield was 0.28g·g, and the bacterial protein content was 52%.

关键词： purple nonsulfur bacteria (PNSB) Rhodobacter sphaeroides Z08 soybean wastewater cost effective

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Life-cycle cost analysis of optimal timing of pavement preservation

Zilong WANG,Hao WANG

《结构与土木工程前沿（英文）》 2017年第11卷第1期页码 17-26 doi: 10.1007/s11709-016-0369-3

摘要： Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analysis (LCCA) model to quantify the impact of pavement preservation on agency cost and vehicle operation cost (VOC) and analyzed the optimal timing of preservation treatments. The international roughness index (IRI) data were extracted from the long-term pavement performance (LTPP) program specific pavement studies 3 (SPS-3) to determine the long-term effectiveness of preservation treatments on IRI deterioration. The traffic loading and the initial IRI value significantly affects life extension and the benefit of agency cost caused by pavement preservation. The benefit in VOC is one to two orders greater in magnitude as compared to the benefit in agency cost. The optimal timing calculated based on VOC is always earlier than the optimal timing calculated based on agency cost. There are considerable differences among the optimal timing of three preservation treatments.

关键词： pavement preservation life-cycle cost analysis agency cost vehicle operation cost

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Comparative cost analysis of three different anesthesia methods in gynecological laparoscopic surgery

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《医学前沿（英文）》 2012年第6卷第3期页码 311-316 doi: 10.1007/s11684-012-0205-7

摘要：

In the current study, we assessed and evaluated the costs and benefits of three popular methods of general anesthesia practiced in our department for gynecological laparoscopic surgery in recent years. Sixty adult female patients who underwent elective gynecological laparoscopic surgery under general anesthesia were randomly divided into three groups: group V, group I and group C. In group V, anesthesia was induced intravenously with midazolam, remifentanil, propofol and vecuronium, and maintained with continuous infusion of propofol and remifentanil. In group I, anesthesia was intravenously induced with midazolam, fentanyl, propofol and vecuronium, and maintained with inhaled isoflurane and intravenous bonus of fentanyl. In group C, anesthesia was induced as in group I, but maintained with isoflurane inhalation combined with propofol-remifentanil infusion. All patients received vecuronium for muscle relaxation. Perioperative incidences of complications and total anesthesia costs for patients in all groups were recorded. In addition, postoperative satisfaction of the patients was also noted, and similar outcomes of the satisfaction were reported in all 60 patients. Although there was no statistical significance among groups, the incidence of postoperative nausea and vomiting were higher in group C, and the rates of shivering and the needs for analgesics were higher in group V. Anesthesia costs in group I were the lowest. Therefore, it is concluded that the costs of anesthesia induced with midazolam, fentanyl, propofol, vecuronium, and maintained with isoflurane, fentanyl and vecuronium are cheapest, and there is no significant difference in patients’ satisfaction and safety among the three above-mentioned methods of anesthesia in our department.

关键词： general anesthesia economics cost

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Lifecycle carbon footprint and cost assessment for coal-to-liquid coupled with carbon capture, storage

《能源前沿（英文）》 2023年第17卷第3期页码 412-427 doi: 10.1007/s11708-023-0879-3

摘要： The coal-to-liquid coupled with carbon capture, utilization, and storage technology has the potential to reduce CO₂ emissions, but its carbon footprint and cost assessment are still insufficient. In this paper, coal mining to oil production is taken as a life cycle to evaluate the carbon footprint and levelized costs of direct-coal-to-liquid and indirect-coal-to-liquid coupled with the carbon capture utilization and storage technology under three scenarios: non capture, process capture, process and public capture throughout the life cycle. The results show that, first, the coupling carbon capture utilization and storage technology can reduce CO₂ footprint by 28%–57% from 5.91 t CO₂/t·oil of direct-coal-to-liquid and 24%–49% from 7.10 t CO₂/t·oil of indirect-coal-to-liquid. Next, the levelized cost of direct-coal-to-liquid is 648–1027 $/t of oil, whereas that of indirect-coal-to-liquid is 653–1065 $/t of oil. When coupled with the carbon capture utilization and storage technology, the levelized cost of direct-coal-to-liquid is 285–1364 $/t of oil, compared to 1101–9793 $/t of oil for indirect-coal-to-liquid. Finally, sensitivity analysis shows that CO₂ transportation distance has the greatest impact on carbon footprint, while coal price and initial investment cost significantly affect the levelized cost of coal-to-liquid.

关键词： coal-to-liquid carbon capture utilization and storage (CCUS) carbon footprint levelized cost of liquid lifecycle assessment

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Floating production storage and offloading systems’ cost and motion performance: A systems thinking application

Rini NISHANTH, Andrew WHYTE, V. John KURIAN

《工程管理前沿（英文）》 2018年第5卷第3期页码 357-368 doi: 10.15302/J-FEM-2018022

摘要：

Floating production storage and offloading (FPSO) units increasingly represent a practical and economic means for deep-water oil extraction and production. Systems thinking gives a unique opportunity to seek a balance between FPSO technical performance(s), with whole-cost; stakeholder decision-making is charged to align different fit-for-use design specification options’ that address technical-motion(s), with respective life-cycle cost analyses (LCCA). Soft system methodology allows situation based analyses over set periods-of-time by diagnosing the problem-at-hand; namely, assessing the antecedents of life-cycle cost relative to FPSO sub-component design alternatives. Alternative mooring- component comparisons for either new-build hulls or refurbished hulls represent an initial necessary consideration to facilitate extraction, production and storage of deep-water oil reserves. Coupled dynamic analysis has been performed to generate FPSO motion in six degrees of freedom using SESAM DeepC, while life-cycle cost analysis (LCAA) studies give net-present-value comparisons reflective of market conditions. A parametric study has been conducted by varying wave heights from 4 – 8 m to understand FPSO motion behavior in the presence of wind and current, as well as comparing the motions of turreted versus spread mooring design alternatives. LCCA data has been generated to compare the cost of such different mooring options/hull conditions over 10 and 25-year periods. Systems thinking has been used to explain the interaction of problem variables; resultantly this paper is able to identify explicit factors affecting the choice of FPSO configurations in terms of motion and whole-cost, toward assisting significantly with the front-end engineering design (FEED) phase of fit-for-purpose configured FPSOs, in waters off Malaysia and Australia.

关键词： FPSO LCCA spread/turret-mooring DeepC cost motion soft-systems

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Estimation of the minimum effective dose of tramadol for postoperative analgesia in infants using the

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《医学前沿（英文）》 2012年第6卷第3期页码 288-295 doi: 10.1007/s11684-012-0208-4

摘要：

Tramadol is a potent analgesic. However, the analgesia efficacy of tramadol, particularly its minimum effective dose (MED), is not clear. The aim of this study is to find MED of tramadol for postoperative analgesia in infants. The continual reassessment method (CRM) was performed to find MED. Infants undergoing surgeries were included in the 3 phases of this series. In each phase, 24 participants were allocated a different tramadol dose. Pain intensity was measured by face, legs, activity, cry, consolability (FLACC) measurement at 3-hour intervals. Tramadol was considered ineffective if the FLACC score was higher than 4 in 10 at anytime. In phase 1, seven dose levels were used within the range 0.1–0.4 mg?kg^-1·h^-1. Phase 1 was insufficient to identify the MED, and we increased the dose to 0.4–0.8 mg?kg^-1·h^-1 in phase 2. Phase 2 was insufficient to identify the MED. In phase 3, local anesthetic wound infiltration was introduced, and the tramadol dose levels tested were the same as in phase 1. The successful analgesia probability of tramadol 0.4 mg?kg^-1?h^-1 was 82.1% (95% CI, 0.742–0.925) in phase 1. In phase 2, it was 84.7% (95% CI, 0.789–0.991) with the dose 0.8 mg?kg^-1?h^-1. Phase 1 and phase 2 were insufficient to identify the MED. In phase 3, the successful analgesia probability for dose 0.35 mg?kg^-1?h^-1was 96.7% (95% CI, 0.853–0.997).We have demonstrated that tramadol provides insufficient analgesia for surgeries considered to cause moderate-to-severe postoperative pain in infants if used as the sole analgesic, and that local anesthetic wound infiltration enhances the efficacy of tramadol.

关键词： tramadol minimum effective dose postoperative analgesia infants continual reassessment method

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分级移动边缘云中节省开销的资源分配 Special Feature on Future Network-Research Article

Ming-shuang JIN, Shuai GAO, Hong-bin LUO, Hong-ke ZHANG

《信息与电子工程前沿（英文）》 2019年第20卷第9期页码 1209-1220 doi: 10.1631/FITEE.1800203

摘要： 5G网络的云化使第三方服务提供商能够在网络边缘部署服务（例如，边缘缓存与边缘计算）。已有工作都是站在特定服务提供商角度，以最大化其收益为目标来研究服务策略（如，内容缓存策略与虚拟CPU分配策略）。然而，尚未有相关工作从网络运营商角度，在满足第三方服务提供商部署需求基础上进行合理、有效的资源分配。本文针对该问题建立了优化模型，目标是最小化所有服务提供商的部署开销。为描述服务提供商的部署需求，将所有应用分为两类，即计算密集型应用和存储密集型应用，并将这两类应用的需求作为优化问题的输入参数。由于建立的数学模型是非凸优化且是NP难问题，设计了基于精英保留策略的遗传算法来求得最优解。通过仿真验证了所设计算法的可行性和有效性。

关键词：边缘云；边缘计算；边缘缓存；资源分配；虚拟机分配

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Developing effective tumor vaccines: basis, challenges and perspectives

XU Qingwen, CHEN Weifeng

《医学前沿（英文）》 2007年第1卷第1期页码 11-19 doi: 10.1007/s11684-007-0003-9

摘要： A remarkable advance in tumor immunology during the last decade is the elucidation of the antigenic basis of tumor recognition and destruction. A variety of tumor antigens have been identified using several strategies including conventional experiments and newly developed bioinformatics. Among these antigens, cancer/testis antigen (CT antigen) is considered to be the most promising target for immunotherapy by vaccination. Successful immunotherapy of tumors requires understanding of the natural relationship between the immune system and tumor in the status of differentiation, invasion and maturation. Continued progress in development of effective cancer vaccines depends on the identification of appropriate target antigens, the establishment of optimal immunization strategies without harmful autoimmune responses and the ability of manipulating tumor microenvironment to circumvent immune suppression and to augment the anti-tumor immune response.

关键词： development conventional identification elucidation Successful immunotherapy

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Manufacturing cost constrained topology optimization for additive manufacturing

Jikai LIU, Qian CHEN, Xuan LIANG, Albert C. TO

《机械工程前沿（英文）》 2019年第14卷第2期页码 213-221 doi: 10.1007/s11465-019-0536-z

摘要： This paper presents a manufacturing cost constrained topology optimization algorithm considering the laser powder bed additive manufacturing process. Topology optimization for additive manufacturing was recently extensively studied, and many related topics have been addressed. However, metal additive manufacturing is an expensive process, and the high manufacturing cost severely hinders the widespread use of this technology. Therefore, the proposed algorithm in this research would provide an opportunity to balance the manufacturing cost while pursuing the superior structural performance through topology optimization. Technically, the additive manufacturing cost model for laser powder bed-based process is established in this paper and real data is collected to support this model. Then, this cost model is transformed into a level set function-based expression, which is integrated into the level set topology optimization problem as a constraint. Therefore, by properly developing the sensitivity result, the metallic additive manufacturing part can be optimized with strictly constrained manufacturing cost. Effectiveness of the proposed algorithm is proved by numerical design examples.

关键词： topology optimization manufacturing cost additive manufacturing powder bed

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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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Low-cost adsorbents for urban stormwater pollution control

Yang Deng

《环境科学与工程前沿（英文）》 2020年第14卷第5期 doi: 10.1007/s11783-020-1262-9

摘要： Abstract • Various low-cost adsorbents are studied for capturing urban stormwater pollutants. • Adsorbents are selected based on both pollutant adsorption and unexpected leaching. • Application modes of adsorbents influence their utilization efficacy in practice. Stormwater represents a major non-point pollution source at an urban environment. To improve the treatment efficacy of stormwater infrastructure, low-cost adsorbents have increasingly gained attention over the past decades. This article aims to briefly discuss several key aspects and principles for utilization of low-cost adsorbents for urban stormwater treatment. To determine whether a low-cost adsorbent is suitable for stormwater treatment, two aspects should be carefully assessed, including: 1) its adsorption mechanisms and behaviors that can influence the binding stre.g.,h, adsorption kinetics, and treatment capacity; and 2) unwanted chemical leaching patterns that can affect the extent of water quality degradation. Furthermore, the application mode of an adsorbent in the system design influences the utilization efficiency. Adsorbents, after dosed to soil media in infrastructure, would eventually become ineffective after oversaturation. In contrast, standalone filters or innovative composite adsorbents (e.g., adsorbent-coated mulch chips) can enable a long-lasting adsorption due to periodic replacement with fresh adsorbents. The aforementioned principles play a key role in the success of urban stormwater treatment with low-cost adsorbents.

关键词： Urban stormwater Runoff pollutants Low-cost adsorbents Adsorption Chemical leaching

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Low-cost green building practice in China: Library of Shandong Transportation College

Yingxin ZHU, Borong LIN, Bin YUAN,

《能源前沿（英文）》 2010年第4卷第1期页码 100-105 doi: 10.1007/s11708-009-0072-3

摘要： This paper introduces the design idea and technique utilized in the Library of Shandong Transportation College, which ranked 1st in the 2nd National Green Buildings Innovation Award in China in March 2007 due to its low cost and climate-oriented green strategy during its design and construction phase, including land saving, energy efficiency, water conservation, and so on. Originally, the place was a landfill site with an odor pool. After reconstruction, it was changed into the construction site of the library with an area of 7000m and a scenery pond. With the integrated use of passive shading, daylighting, ventilation with atriums, high-insulation materials, underground duct ventilation, and the substitution of cooling tower with the pond water, the HVAC load design indexes are 59 W/m and 21.8 W/m for space cooling and heating, respectively, much lower than the newly issued Chinese energy efficient design code for public buildings. Moreover, a set of measures is utilized for water conversation, material saving, and improvement of indoor environmental quality. After three years of operation, the real effect has been validated by electricity meter and field measurement. The total initial cost for the building with the above mentioned integrated technologies was only RMB 2150 per square meter, which was worth spending in China due to the climatic adaptability and the relative low cost.

关键词： green building low cost technique energy efficiency integrated strategy