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Sustainable design of sanitation system based on material and value flow analysis for urban slum in Indonesia

Ken USHIJIMA, Mitsuteru IRIE, Neni SINTAWARDANI, Jovita TRIASTUTI, Umi HAMIDAH, Tadaharu ISHIKAWA, Naoyuki FUNAMIZU

《环境科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 120-126 doi: 10.1007/s11783-012-0460-5

摘要: Material flow analysis (MFA) and value flow analysis (VFA) were applied to the sanitation system in an urban slum in Indonesia. Based on the results of the MFA and VFA, garbage and excreta disposal costs were evaluated to be 0.7% and 1.1%, respectively, of per capita income. Such value flows seem reasonable in light of the recognized affordability to pay (ATP) standard. However, current excreta disposal methods create negative impacts on downstream populations. Because such disadvantages do not go back to disposers, but passed to downstream, the current value flow structure does not motivate individual toilet users to install treatment facility. Based on current material and value flow structures, a resource recycling sanitation system scenario was examined. Based on VFA, an affordable initial cost for such a system was calculated; this was found to be comparable in price to a cheaper composting toilet that is currently available in the market.

关键词: material flow     value flow     resource recycling system     sustainable design     initial cost     urban slum    

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

《农业科学与工程前沿(英文)》 2016年 第3卷 第2期   页码 161-170 doi: 10.15302/J-FASE-2016104

摘要: Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400–3100 kg·hm ) is recommended for the conservation of water and soil in northern China.

关键词: infiltration     initial soil water content     rainfall simulation     soil loss     straw mulching    

Evacuation strategies for vertical ship lift during initial fire: Integrated application of stairs and

Shu CHEN, Menghan SHANG, Jianping WANG

《工程管理前沿(英文)》 2021年 第8卷 第1期   页码 135-147 doi: 10.1007/s42524-020-0125-1

摘要: Vertical ship lifts (VSLs) are widely used in navigation facilities worldwide because of their efficiency and low cost. Although several researchers have investigated fire evacuation strategies for reducing potential safety hazards in VSLs, an effective and integrated application of stairs and elevators when a fire occurs in a VSL is necessary. Several evacuation routes were analyzed according to VSL structure and evacuation times in this study. Objective function corresponding to the minimum vertical evacuation time and related simulation model was subsequently developed to obtain a cooperative evacuation plan considering different numbers of evacuees. The Three Gorges ship lift was used as an example, and simulation results indicate that number of evacuees and exit selection are the main influencing factors of the total evacuation time in the stair- and elevator-coordinated evacuation mode. Furthermore, the distance between people trapped in ship reception chamber and evacuation exits affects evacuees’ choice of exits. The proposed model can provide a theoretical reference for evacuation research during initial fire events in VSLs.

关键词: vertical ship lift     initial fire     fire evacuation     numerical simulation     stair     elevator    

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    

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

null

《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    

Initial stiffness and moment resistance of reinforced joint with end-plate connection

Sufang WANG, Yiyi CHEN,

《结构与土木工程前沿(英文)》 2009年 第3卷 第4期   页码 345-351 doi: 10.1007/s11709-009-0054-x

摘要: In beam-to-column joint with bolted end-plate connection, the structural details of column flange reinforced by backing plate and column web panel reinforced by supplementary plate are analyzed. The joint is divided into some basic components, and the initial stiffness of each component is obtained. Especially, the initial stiffness of reinforced components is drawn by theoretical model and finite element analysis. The initial stiffness of reinforced joint can be obtained by assembling the initial stiffness of each component. The design moment resistance of column flange reinforced by backing plate is deduced based on yield line method, and the design moment resistances of other components are deduced based on present codes. The design moment resistance of the reinforced joint is then determined by the minimum of the design moment resistances of all components. By comparison with the results of finite element calculation, it is verified that the method to calculate the initial stiffness of reinforced joint is accurate enough to be used to estimate the rigid behavior of the joint and to make parametric study.

关键词: steel structure     end-plate connection     backing plate     supplementary web plate     initial stiffness     moment resistance    

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    

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    

余弦忆导忆阻系统周期变化初值位移调控行为 Regular Papers

Mo CHEN, Xue REN, Hua-gan WU, Quan XU, Bo-cheng BAO

《信息与电子工程前沿(英文)》 2019年 第20卷 第12期   页码 1706-1716 doi: 10.1631/FITEE.1900360

摘要: 利用一种新型余弦忆导理想忆阻,构造一个四维忆阻系统。由于忆导函数特殊的非线性,忆阻系统具有沿忆阻内部状态变量坐标轴分布的线平衡点集(0, 0, 0, δ),且平衡点集稳定性随δ变化而周期性演化。数值仿真揭示了忆阻系统非线性、一维的初值位移调控行为,它不仅可由忆阻状态初值触发,也可由其他两个系统状态初值引发。特别地,在位移调控路线上,可以观测到多种具有不同位置和拓扑结构的共存吸引子。通过PSIM电路仿真对该特殊动力学特性进行了验证。

关键词: 初值位移调控;忆阻系统;忆导;线平衡点集    

Nonlinear analysis of pre-tensioned glass wall facade by stability function with initial imperfection

Siu-Lai CHAN, Yaopeng LIU, Andy LEE,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 376-382 doi: 10.1007/s11709-010-0086-2

摘要: Pre-tensioned high strength trusses using alloy steel bar are widely used as glass wall supporting systems because of the high degree of transparency. The breakage of glass panes in this type of system occurs occasionally, likely to be due to error in design and analysis in addition to other factors like glass impurity and stress concentration around opening in a spider system. Most design does not consider the flexibility of supports from finite stiffness of supporting steel or reinforced concrete beams. The resistance of lateral wind pressure of the system makes use of high tension force coupled with the large deflection effect, both of which are affected by many parameters not generally considered in conventional structures. In the design, one must therefore give a careful consideration on various effects, such as support settlement due to live loads and material creep, temperature change, pre-tension force, and wind pressure. It is not uncommon to see many similar glass wall systems fail in the wind load test chambers under a design wind speed. This paper presents a rigorous analysis and design of this type of structural systems used in a project in Hong Kong, China. The stability function with initial curvature is used in place of the cubic function, which is only accurate for linear analysis. The considerations and analysis techniques are believed to be of value to engineers involved in the design of the structural systems behaving nonlinearly.

关键词: tension system     glass wall     nonlinear analysis     pre-tensioning     second-order analysis    

Influence of initial curing conditions and exposure environments on chloride migration in concrete using

Wen XUE, Weiliang JIN, Hiroshi YOKOTA,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 348-353 doi: 10.1007/s11709-010-0077-3

摘要: To investigate the influence of initial curing conditions and exposure environments on chloride ions’ migration in concrete, the specimens that were cured in different conditions and placed in several marine environments were studied. The amount of chloride ions passing through the specimen’s section was monitored in the accelerated chloride migration test. The effective chloride diffusion coefficients () were calculated from the steady-state on the basis of Nernst-Planck’s equation. The results indicated that the initial curing conditions and the wet-dry interval of external environments have coupling influence on effective diffusion coefficient of chloride ion significantly. reflected the density and pore connectivity of concrete. The co-effects of the initial curing condition and following exposure environment should be taken into account in durability design for concrete structure located in marine environment.

关键词: durability     effective diffusion coefficient     steady-state     migration test    

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    

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    

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    

Benefit-based cost allocation for residentially distributed photovoltaic systems in China: A cooperative

Xi LUO, Xiaojun LIU, Yanfeng LIU, Jiaping LIU, Yaxing WANG

《工程管理前沿(英文)》 2021年 第8卷 第2期   页码 271-283 doi: 10.1007/s42524-019-0083-7

摘要: Distributed photovoltaic (PV) systems have constantly been the key to achieve a low-carbon economy in China. However, the development of Chinese distributed PV systems has failed to meet expectations because of their irrational profit and cost allocations. In this study, the methodology for calculating the levelized cost of energy (LCOE) for PV is thoroughly discussed to address this issue. A mixed-integer linear programming model is built to determine the optimal system operation strategy with a benefit analysis. An externality-corrected mathematical model based on Shapley value is established to allocate the cost of distributed PV systems in 15 Chinese cities between the government, utility grid and residents. Results show that (i) an inverse relationship exists between the LCOEs and solar radiation levels; (ii) the government and residents gain extra benefits from the utility grid through net metering policies, and the utility grid should be the highly subsidized participant; (iii) the percentage of cost assigned to the utility grid and government should increase with the expansion of battery bank to weaken the impact of demand response on increasing theoretical subsidies; and (iv) apart from the LCOE, the local residential electricity prices remarkably impact the subsidy calculation results.

关键词: solar photovoltaic     cost allocation     cooperative game theory     Shapley value     mixed-integer linear programming     levelized cost of energy    

标题 作者 时间 类型 操作

Sustainable design of sanitation system based on material and value flow analysis for urban slum in Indonesia

Ken USHIJIMA, Mitsuteru IRIE, Neni SINTAWARDANI, Jovita TRIASTUTI, Umi HAMIDAH, Tadaharu ISHIKAWA, Naoyuki FUNAMIZU

期刊论文

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

期刊论文

Evacuation strategies for vertical ship lift during initial fire: Integrated application of stairs and

Shu CHEN, Menghan SHANG, Jianping WANG

期刊论文

Life-cycle cost analysis of optimal timing of pavement preservation

Zilong WANG,Hao WANG

期刊论文

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

null

期刊论文

Initial stiffness and moment resistance of reinforced joint with end-plate connection

Sufang WANG, Yiyi CHEN,

期刊论文

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

期刊论文

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

Rini NISHANTH, Andrew WHYTE, V. John KURIAN

期刊论文

余弦忆导忆阻系统周期变化初值位移调控行为

Mo CHEN, Xue REN, Hua-gan WU, Quan XU, Bo-cheng BAO

期刊论文

Nonlinear analysis of pre-tensioned glass wall facade by stability function with initial imperfection

Siu-Lai CHAN, Yaopeng LIU, Andy LEE,

期刊论文

Influence of initial curing conditions and exposure environments on chloride migration in concrete using

Wen XUE, Weiliang JIN, Hiroshi YOKOTA,

期刊论文

Manufacturing cost constrained topology optimization for additive manufacturing

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

期刊论文

Low-cost adsorbents for urban stormwater pollution control

Yang Deng

期刊论文

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

Yingxin ZHU, Borong LIN, Bin YUAN,

期刊论文

Benefit-based cost allocation for residentially distributed photovoltaic systems in China: A cooperative

Xi LUO, Xiaojun LIU, Yanfeng LIU, Jiaping LIU, Yaxing WANG

期刊论文