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Techno-economic analysis of the adoption of electric vehicles

Donald KENNEDY, Simon P. PHILBIN

《工程管理前沿(英文)》 2019年 第6卷 第4期   页码 538-550 doi: 10.1007/s42524-019-0048-x

摘要: Significant advances in battery technology are creating a viable marketspace for battery powered passenger vehicles. Climate change and concerns over reliable supplies of hydrocarbons are aiding in the focus on electric vehicles. Consumers can be influenced by marketing and emotion resulting in behaviors that may not be in line with their stated objectives. Although sales of electric vehicles are accelerating, it may not be clear that purchasing an electric vehicle is advantageous from an economic or environmental perspective. A techno- economic analysis of electric vehicles comparing them against hybrids, gasoline and diesel vehicles is presented. The results show that the complexity of electrical power supply, infrastructure requirements and full life cycle concerns show that electric vehicles have a place in the future but that ongoing improvements will be required for them to be clearly the best choice for a given situation.

关键词: BEV     battery powered electric vehicle     environmental impact of electric vehicles     techno-economic analysis     gasoline versus electric powered cars     diesel versus electric cars     consumer behaviour    

ENVIRONMENTAL ATTITUDES AND CONSUMER PREFERENCE FOR ENVIRONMENTALLY-FRIENDLY BEVERAGE PACKAGING: THEROLE OF INFORMATION PROVISION AND IDENTITY LABELING IN INFLUENCING CONSUMER BEHAVIOR

《农业科学与工程前沿(英文)》 2023年 第10卷 第1期   页码 95-108 doi: 10.15302/J-FASE-2022478

摘要:

● Consumer preference for environmentally-friendly beverage packaging was investigated.

关键词: China     consumer preference     food and beverage packaging     green identity label     information treatment     plastics    

ANN-based empirical modelling of pile behaviour under static compressive loading

Abdussamad ISMAIL

《结构与土木工程前沿(英文)》 2018年 第12卷 第4期   页码 594-608 doi: 10.1007/s11709-017-0446-2

摘要: Artificial neural networks have been widely used over the past two decades to successfully develop empirical models for a variety of geotechnical problems. In this paper, an empirical model based on the product-unit neural network (PUNN) is developed to predict the load-deformation behaviour of piles based SPT values of the supporting soil. Other parameters used as inputs include particle grading, pile geometry, method of installation as well as the elastic modulus of the pile material. The model is trained using full-scale pile loading tests data retrieved from FHWA deep foundations database. From the results obtained, it is observed that the proposed model gives a better simulation of pile load-deformation curves compared to the Fleming’s hyperbolic model and t-z approach.

关键词: piles in compression     load-deformation behaviour     product-unit neural network    

Investigation of the hydro-mechanical behaviour of compacted expansive clay

Yujun CUI, An Ninh TA, Anh Minh TANG, Yingfa LU,

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 154-164 doi: 10.1007/s11709-010-0019-0

摘要: The hydro-mechanical behaviour of compacted expansive Romainville clay was investigated. The soil was air-dried, crushed, and passed through a 2 mm sieve before being statically compacted to a dry density of 1.35 Mg/m. The mechanical behaviour was investigated by tests in oedometer with controlled suction using the vapor equilibrium technique (suction = 0, 9, 39, and 110 MPa). The vertical stress was applied in the range of 0–800 kPa. The experimental results are shown as follows: 1) wetting-induced swelling was higher at lower vertical stresses; 2) the vertical stress under which no swelling occurred during water flooding was estimated at 60 kPa, which can be considered as the swelling pressure of the soil tested; 3) the soil compressibility (changes of volume upon stress increases) was strongly influenced by the soil suction: the lower the suction, the higher the compressibility. The hydraulic behaviour was investigated using a large-scale infiltration chamber (800 mm × 1000 mm in section and 1000 mm high). The large size of the soil column allowed burying the volumetric water content sensors (ThetaProbe) without significantly affecting the water transfer and the soil swelling during infiltration. The soil suction was monitored along the soil height (every 100 mm) using various relative humidity sensors and psychrometers. In the infiltration test, water was kept on the soil surface and changes in suction and volumetric water content were monitored for 338 d. The wetting front has reached the bottom of the soil column at the end of the test. The data from the simultaneous monitoring of suction and water content were used to determine the water retention curve and the unsaturated hydraulic conductivity using the instantaneous profile method. It has been observed that the soil water retention curve depends on the soil depth; that is to be related to the soil depth-dependent swelling. The unsaturated hydraulic conductivity was found to be quite low, comprised between 3 × 10 m/s (at saturated state) and 10 m/s (at about 100 MPa suction).

关键词: Romainville clay     suction control     oedometer test     large infiltration task     hydro-mechanical behaviour    

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

《机械工程前沿(英文)》 2013年 第8卷 第2期   页码 127-136 doi: 10.1007/s11465-013-0254-x

摘要:

In this paper we investigate the nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of defects. The nonlinear developed lumped-mass model includes eight degrees of freedom with two nonlinear hertzian contacts. The first one is located between cam and first roller while the second is between second roller and the sliding rod. The nonlinear dynamic behaviour is described by second order differential equations which are resolved by using the implicit Newmark algorithm combined with the Newton-Raphson iterative scheme. The influence of the cam profile error on the dynamic behaviour is also investigated.

关键词: cam     nonlinear behaviour     oscillating roller follower     profile error    

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

《结构与土木工程前沿(英文)》 2008年 第2卷 第2期   页码 116-122 doi: 10.1007/s11709-008-0015-9

摘要: Stresses and deflections were measured in various semi-continuous composite beams. The bending and rotational capacities of the composite connections were measured in terms of beam curvatures and deflections by using two full-scale semi-rigid composite frames with monotonic loadings. The effect of semi-rigid connections on the performance of composite beams with various loadings was compared with predictions and codes. The tests show that the semi-continuous composite beams are more economic and effective than the simple or continuous composite beams. The semi-rigid connections affect the bending capacities and beam deflections, so the connection behavior should be considered in the design of composite beams. Yielding analysis of the steel beam bottom flange has some influence on the deflection calculation of composite beams.

关键词: rotational     effective     deflection calculation     semi-continuous composite     full-scale semi-rigid    

Effect of embedment length of untreated natural fibres on the bond behaviour in cement mortar

Gudimella RAMAKRISHNA, Sriraman PRIYADHARSHINI

《结构与土木工程前沿(英文)》 2018年 第12卷 第4期   页码 454-460 doi: 10.1007/s11709-017-0454-2

摘要: The present investigation is focused on studying the effects of various matrices with 1:3, 1:4 and 1:5 mortars and fibre types of sisal and coir on the bond behavior at various ages of curing, i.e., 24 h, 3 d, 7 d and 28 d. The other parameters included in the investigation are water/cement (w/c) ratio, sand gradation and embedment length of fibres. In addition, the type of failure of sisal and coir fibres for different mixes of mortars at various curing ages is also reported. From the results, it is seen that the bond strength is improving with respect to age of curing in case of sisal fibres, but decreases in case of coir fibres. The failure of fibres due to fibre fracture is observed in sisal fibres and fibre pullout is observed in coir fibres. The other varying parameters such as mortar mixes, sand gradation, w/c ratio and embedded length also showed significant effect on bond behaviour of sisal and coir fibre with the cement mortar mixes.

关键词: bond strength     cement mortar     natural fibre     pullout test     type of failure    

Global challenges of food safety for China

Joseph J. JEN

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 291-293 doi: 10.15302/J-FASE-2017167

摘要:

Ever since the Melamine event, China has faced challenges of food safety both domestically and globally. With the economic development, the Chinese consumers are demanding high quality, nutritious, and safe foods from the food industry but are not willing to pay higher prices. The Chinese food chain system of mostly small and medium enterprises presents challenges to the government to monitor and implement food safety laws and regulations. The academia and media are learning to take on their responsibilities with some success. Discussions and potential solutions of the global challenges of the five pillars for the food safety in China are presented here.

关键词: food safety     challenges     food industry     government     academia     media     consumer    

TRANSFORMATION OF FOOD SYSTEMS: HOW CAN IT BE FINANCED?

《农业科学与工程前沿(英文)》 2023年 第10卷 第1期   页码 109-123 doi: 10.15302/J-FASE-2023483

摘要:

● The analysis of financing for the transformation of food systems requires first a consideration of costs.

关键词: financial markets     food systems     development financing     consumer expenditures     public budgets     Sustainable Development Goals    

A systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

《能源前沿(英文)》 2019年 第13卷 第2期   页码 386-398 doi: 10.1007/s11708-017-0497-z

摘要: The potential to save energy in existing consumer electrical appliances is very high. One of the ways to achieve energy saving and improve energy use awareness is to recognize the energy consumption of individual electrical appliances. To recognize the energy consumption of consumer electrical appliances, the load disaggregation methodology is utilized. Non-intrusive appliance load monitoring (NIALM) is a load disaggregation methodology that disaggregates the sum of power consumption in a single point into the power consumption of individual electrical appliances. In this study, load disaggregation is performed through voltage and current waveform, known as the - trajectory. The classification algorithm performs cropping and image pyramid reduction of the - trajectory plot template images before utilizing the principal component analysis (PCA) and the -nearest neighbor ( -NN) algorithm. The novelty of this paper is to establish a systematic approach of load disaggregation through - trajectory-based load signature images by utilizing a multi-stage classification algorithm methodology. The contribution of this paper is in utilizing the “ -value,” the number of closest data points to the nearest neighbor, in the -NN algorithm to be effective in classification of electrical appliances. The results of the multi-stage classification algorithm implementation have been discussed and the idea on future work has also been proposed.

关键词: load disaggregation     voltage-current (V-I) trajectory     multi-stage classification algorithm     principal component analysis (PCA)     k-nearest neighbor (k-NN)    

从原子结构探讨贵金属在提取冶金过程中的行为

陈景

《中国工程科学》 1999年 第1卷 第2期   页码 34-40

摘要:

从原子结构特征分析了第Ⅷ族和IB族中Fe、Co、Ni、Cu 3d贱金属元素与其余8个贵金属元素化学性质的差异,以及Ru、Rh、Pd、Ag 4d贵金属与Os、Ir、Pt、Au 5d贵金属化学性质的差异。指出横向比较时,它们的化学稳定性都是从左到右增大;纵向比较时,化学稳定性是3d≤4d<5d。以从硫化铜镍矿中提取富集贵金属为例,讨论了焙烧-还原熔炼-氧化吹炼等火法过程及电解富集、阳极泥硫酸化处理、湿法氯化、加压氧化、选择性还原等湿法过程中贵金属的行为。

关键词: 原子结构     贵金属     提取冶金    

Parameter studies on impact in a lap joint

Amir M. RAHMANI,Elizabeth K. ERVIN

《机械工程前沿(英文)》 2015年 第10卷 第1期   页码 64-77 doi: 10.1007/s11465-014-0322-x

摘要:

To represent a loose lap joint, a beam impacting four springs with gaps is modeled. Modal analysis with base excitation is solved, and time histories of contact points are closely monitored. Using the impulse during steady state response, six influential parameters are studied: damping ratio, contact stiffness, intermediate contact position, gap, excitation amplitude and beam height. For all parameters, the system response is highly controlled by modes with two contacting springs. Each parameter’s effect on system response is presented including unstable regions, unique trend behaviours result. Recommendations for structural designers are also noted.

关键词: impact mechanics     contact     joint behaviour     modal analysis     parameter study    

Behaviour of self-centring shear walls——A state of the art review

《结构与土木工程前沿(英文)》 2023年 第17卷 第1期   页码 53-77 doi: 10.1007/s11709-022-0850-0

摘要: The application of unbonded post-tensioning (PT) in structural walls has led to the development of advanced self-centring (rocking) shear wall systems that has significant advantages, including accelerated construction due to the incorporation of prefabricated elements and segmental construction for different materials (e.g., concrete, masonry, and timber), reduced residual drifts, and little damage upon extreme seismic and wind loads. Concrete, masonry, and timber are often used for the construction of unbonded PT structural wall systems. Despite extensive research since the 1980s, there are no well-established design guidelines available on the shear wall configuration with the required energy dissipation system, joint’s locations and acceptance criteria for shear sliding, confinement, seismic performance factors, PT loss, PT force range and residual drifts of shear walls subjected to lateral loads. In this research a comprehensive state-of-the-art literature review was performed on self-centring shear wall system. An extensive study was carried out to collect a database of 100 concrete, masonry, and self-centring shear wall tests from the literature. The established database was then used to review shear walls’ configurations, material, and components to benchmark requirements applicable for design purposes. The behaviour of concrete, masonry and timber shear walls were compared and critically analysed. The general behaviour, force-displacement performance of the walls, ductility, and seismic response factors, were critically reviewed and analysed for different self-centring wall systems to understand the effect of different parameters including configurations of the walls, material used for construction of the wall (concrete, masonry, timber) and axial stress ratio. The outcome of this research can be used to better understand the behaviour of self-centring wall system in order to develop design guidelines for such walls.

关键词: self-centring shear walls     rocking walls     energy dissipation     seismic performance factors     PT loss     residual drift    

Nonlinear experimental response of non-conventional composite steel and concrete connection

Tobia ZORDAN, Bruno BRISEGHELLA

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 42-49 doi: 10.1007/s11709-008-0058-y

摘要: An experiment was carried out on a set of full-scale specimens of a non-conventional connection between a concrete column and a composite steel and concrete beam defined on the basis of a number of requirements. The proposed connection, conceived in the ambit of semi-rigid joints, is aimed at combining general ease of construction with a highly simplified assembly procedure with a satisfying transmission of hogging moment at supports in continuous beams. For this purpose, the traditional shear studs used at the interface between the steel beam and the upper concrete slab, are also employed at the ends of the steel profiles welded horizontally to the end plates. The test is aimed at investigating the hogging moment response of the connection under incremental loads until failure.

关键词: composite connections     nonlinear behaviour     hogging moment     monotonic tests    

Exploring price effects on the residential water conservation technology diffusion process: a case study of Tianjin city

Junying CHU, Hao WANG, Can WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第5期   页码 688-698 doi: 10.1007/s11783-013-0559-3

摘要: Reforms of the water pricing management system and the establishment of a flexible water pricing system are significant for cities in northern China to tackle their critical water issues. The WATAP (Water conservation Technology Adoption Processes) model is developed in order to capture the water conservation technology adoption process under different price scenarios with disaggregate water demands down to the end use level. This model is explicitly characterized by the technological selection process under maximum marginal benefit assumption by different categories of households. In particular, when households need to purchase water devices in the provision market with the consideration of complex factors such as the life span, investment and operating costs of the device, as well as the regulated water price by the government. Applied to Tianjin city, four scenarios of water price evolutions for a long-term perspective (from year 2011 to 2030) are considered, including BAU (Business As Usual), SP1 (Scenario of Price increase with constant annual rate), SP2 (Scenario of Price increase every four years) and SP3 (Scenario of Price increase with affordable constraint), considering many factors such as historic trends, affordability and incentives for conservation. Results show that on aggregate 2.3%, 11.0% and 18.2% of fresh water can be saved in the residential sector in scenario SP1, SP2 and SP3, respectively, compared with the BAU scenario in the year 2030. The water price signals can change the market shares of different water appliances, as well as the water end use structure of households, and ultimately improve water use efficiency. The WATAP model may potentially be a helpful tool to provide insights for policy makers on water conservation technology policy analysis and assessment.

关键词: technology selection     model optimization     water price     scenario analysis     consumer behavior    

标题 作者 时间 类型 操作

Techno-economic analysis of the adoption of electric vehicles

Donald KENNEDY, Simon P. PHILBIN

期刊论文

ENVIRONMENTAL ATTITUDES AND CONSUMER PREFERENCE FOR ENVIRONMENTALLY-FRIENDLY BEVERAGE PACKAGING: THEROLE OF INFORMATION PROVISION AND IDENTITY LABELING IN INFLUENCING CONSUMER BEHAVIOR

期刊论文

ANN-based empirical modelling of pile behaviour under static compressive loading

Abdussamad ISMAIL

期刊论文

Investigation of the hydro-mechanical behaviour of compacted expansive clay

Yujun CUI, An Ninh TA, Anh Minh TANG, Yingfa LU,

期刊论文

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

期刊论文

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

期刊论文

Effect of embedment length of untreated natural fibres on the bond behaviour in cement mortar

Gudimella RAMAKRISHNA, Sriraman PRIYADHARSHINI

期刊论文

Global challenges of food safety for China

Joseph J. JEN

期刊论文

TRANSFORMATION OF FOOD SYSTEMS: HOW CAN IT BE FINANCED?

期刊论文

A systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

期刊论文

从原子结构探讨贵金属在提取冶金过程中的行为

陈景

期刊论文

Parameter studies on impact in a lap joint

Amir M. RAHMANI,Elizabeth K. ERVIN

期刊论文

Behaviour of self-centring shear walls——A state of the art review

期刊论文

Nonlinear experimental response of non-conventional composite steel and concrete connection

Tobia ZORDAN, Bruno BRISEGHELLA

期刊论文

Exploring price effects on the residential water conservation technology diffusion process: a case study of Tianjin city

Junying CHU, Hao WANG, Can WANG

期刊论文