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Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infraredspectroscopy: Implications for enabling cell culture process analytical technology?

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

《化学科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 386-406 doi: 10.1007/s11705-015-1533-3

摘要: Compared to small molecule process analytical technology (PAT) applications, biotechnology product PAT applications have certain unique challenges and opportunities. Understanding process dynamics of bioreactor cell culture process is essential to establish an appropriate process control strategy for biotechnology product PAT applications. Inline spectroscopic techniques for real time monitoring of bioreactor cell culture process have the distinct potential to develop PAT approaches in manufacturing biotechnology drug products. However, the use of inline Fourier transform infrared (FTIR) spectroscopic techniques for bioreactor cell culture process monitoring has not been reported. In this work, real time inline FTIR Spectroscopy was applied to a lab scale bioreactor mAb IgG3 cell culture fluid biomolecular dynamic model. The technical feasibility of using FTIR Spectroscopy for real time tracking and monitoring four key cell culture metabolites (including glucose, glutamine, lactate, and ammonia) and protein yield at increasing levels of complexity (simple binary system, fully formulated media, actual bioreactor cell culture process) was evaluated via a stepwise approach. The FTIR fingerprints of the key metabolites were identified. The multivariate partial least squares (PLS) calibration models were established to correlate the process FTIR spectra with the concentrations of key metabolites and protein yield of in-process samples, either individually for each metabolite and protein or globally for all four metabolites simultaneously. Applying the 2 derivative pre-processing algorithm to the FTIR spectra helps to reduce the number of PLS latent variables needed significantly and thus simplify the interpretation of the PLS models. The validated PLS models show promise in predicting the concentration profiles of glucose, glutamine, lactate, and ammonia and protein yield over the course of the bioreactor cell culture process. Therefore, this work demonstrated the technical feasibility of real time monitoring of the bioreactor cell culture process via FTIR spectroscopy. Its implications for enabling cell culture PAT were discussed.

关键词: process analytical technology (PAT)     Fourier-transform infrared (FTIR) spectroscopy     partial least squares (PLS) regression     mouse IgG3     bioreactor cell culture process     real time process monitoring    

Evaluating and structuring indicators for wetland assessment

Xuehua LIU, Yan SUN,

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 221-227 doi: 10.1007/s11783-010-0029-0

摘要: Wetland assessment has been a popular field of research worldwide. However, various indicators have been used in wetland assessment for different purposes and backgrounds and also because of the research limitations. Therefore, a more comprehensive, sound, and efficient indicator system is needed for researchers’ referencing to evaluate wetlands. After an extensive review of wetland assessment literatures, the reported indicators were evaluated using the developed assessment system, based on the Analytical Hierarchy Process (AHP) with three main goals: nature protection, function utilization, and sustainable development. Each indicator was evaluated using two methods. The first method was to study the percentage of the indicator application, and the second was to assess the weighted ratios assigned to the indicators according to principles of comparability, typicality, sensibility, and availability. The results of these two methods were compared to study the commonalities and specialties of the indicators. They also showed that some indicators were widely used, including biodiversity, weather and climate, hydrological change, and the output of wetland. On the other hand, other sustainable indicators were easily ignored, such as environmental carrying capacity and wetland planning. Furthermore, an indicator system for wetland assessment was structured and strategized to discuss how to choose indicators for wetland assessment under different conditions. The proposed approach can be used to guide the process of wetland assessments in the future.

关键词: wetland assessment     indicators     Analytical Hierarchy Process (AHP)     comparison    

Advances in the slurry reactor technology of the anthraquinone process for H

Hongbo Li, Bo Zheng, Zhiyong Pan, Baoning Zong, Minghua Qiao

《化学科学与工程前沿(英文)》 2018年 第12卷 第1期   页码 124-131 doi: 10.1007/s11705-017-1676-5

摘要: This paper overviews the development of the anthraquinone auto-oxidation (AO) process for the production of hydrogen peroxide in China and abroad. The characteristics and differences between the fixed-bed and fluidized-bed reactors for the AO process are presented. The detailed comparison indicates that the production of hydrogen peroxide with the fluidized-bed reactor has many advantages, such as lower operation cost and catalyst consumption, less anthraquinone degradation, higher catalyst utilization efficiency, and higher hydrogenation efficiency. The key characters of the production technology of hydrogen peroxide based on the fluidized-bed reactor developed by the Research Institute of Petroleum Processing, Sinopec are also disclosed. It is apparent that substituting the fluidized-bed reactor for the fixed-bed reactor is a major direction of breakthrough for the production technology of hydrogen peroxide in China.

关键词: anthraquinone process     fixed-bed reactor     slurry-bed reactor     hydrogen peroxide    

Computer aided process planning system based on workflow technology and integrated bill of material tree

LU Chun-guang, MENG Li-li

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 305-312 doi: 10.1007/s11465-006-0039-6

摘要: It is extremely important for procedure of process design and management of process data for product life cycle in Computer Aided Process Planning (CAPP) system, but there are many shortcomings with traditional CAPP system in these respects. To solve these questions, application of workflow technology in CAPP system based on web-integrated Bill of Material (BOM) tree is discussed, and a concept of integrated BOM tree was brought forward. Taking integrated BOM as the thread, CAPP systematic technological process is analyzed. The function, system architecture, and implementation mechanism of CAPP system based on Browser/Server and Customer/Server model are expatiated. Based on it, the key technologies of workflow management device were analyzed. Eventually, the implementation mechanism of integrated BOM tree was analyzed from viewpoints of material information encoding, organization node design of integrated BOM tree, transformation from Engineering BOM (EBOM) to Process BOM(PBOM), and the programming implementation technology.

关键词: PBOM     systematic technological     implementation technology     management     workflow technology    

长江堤防安全评价的理论 方法和实现策略

李青云,张建民

《中国工程科学》 2005年 第7卷 第6期   页码 7-13

摘要:

对长江堤防安全评价的理论与方法进行了较为系统的阐述。重点论述了长江中下游堤防的特点和破坏机理,分析了与堤防安全有关的基本因素;针对堤防安全评价的层次性和动态性等特点,初步建立了长江中下游堤防安全评价的理论框架,提出了堤防安全评价的流程与方法。

关键词: 长江堤防     安全评价     指标体系     层次分析    

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

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    

Lightweight design of an electric bus body structure with analytical target cascading

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0718-y

摘要: Lightweight designs of new-energy vehicles can reduce energy consumption, thereby improving driving mileage. In this study, a lightweight design of a newly developed multi-material electric bus body structure is examined in combination with analytical target cascading (ATC). By proposing an ATC-based two-level optimization strategy, the original lightweight design problem is decomposed into the system level and three subsystem levels. The system-level optimization model is related to mass minimization with all the structural modal frequency constraints, while each subsystem-level optimization model is related to the sub-structural performance objective with sub-structure mass constraints. To enhance the interaction between two-level systems, each subsystem-level objective is reformulated as a penalty-based function coordinated with the system-level objective. To guarantee the accuracy of the model-based analysis, a finite element model is validated through experimental modal test. A sequential quadratic programming algorithm is used to address the defined optimization problem for effective convergence. Compared with the initial design, the total mass is reduced by 49 kg, and the torsional stiffness is increased by 17.5%. In addition, the obtained design is also validated through strength analysis.

关键词: electric vehicle     body in white (BIW)     lightweight     analytical target cascading (ATC)    

Improved analytical model for residual stress prediction in orthogonal cutting

null

《机械工程前沿(英文)》 2014年 第9卷 第3期   页码 249-256 doi: 10.1007/s11465-014-0310-1

摘要:

The analytical model of residual stress in orthogonal cutting proposed by Jiann is an important tool for residual stress prediction in orthogonal cutting. In application of the model, a problem of low precision of the surface residual stress prediction is found. By theoretical analysis, several shortages of Jiann’s model are picked out, including: inappropriate boundary conditions, unreasonable calculation method of thermal stress, ignorance of stress constraint and cyclic loading algorithm. These shortages may directly lead to the low precision of the surface residual stress prediction. To eliminate these shortages and make the prediction more accurate, an improved model is proposed. In this model, a new contact boundary condition between tool and workpiece is used to make it in accord with the real cutting process; an improved calculation method of thermal stress is adopted; a stress constraint is added according to the volume-constancy of plastic deformation; and the accumulative effect of the stresses during cyclic loading is considered. At last, an experiment for measuring residual stress in cutting AISI 1045 steel is conducted. Also, Jiann’s model and the improved model are simulated under the same conditions with cutting experiment. The comparisons show that the surface residual stresses predicted by the improved model is closer to the experimental results than the results predicted by Jiann’s model.

关键词: residual stress     analytical model     orthogonal cutting     cutting force     cutting temperature    

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1359-1371 doi: 10.1007/s11709-020-0658-8

摘要: In this study, the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical method. The material properties including tensile modulus, shear modulus, and density of the plate were assumed to be spatially varying and uncertain. Gaussian fields with first-order Markov kernels were utilized to define the aforementioned material properties. The stochastic fields were decomposed via application of the Karhunen-Loeve theorem. A first-order shear deformation theory was assumed, following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic energies. The stochastic equations of motion of the plate were obtained using the variational principle. The deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies, and the corresponding mode shapes of the plate were determined using a polynomial chaos approach. The proposed method significantly reduced the size of the mathematical models of the structure, which is very useful for enhancing the computational efficiency of stochastic simulations. The methodology was verified using a stochastic finite element method and the available results in literature. The sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated, and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词: composite plate     spatially varying stochastic properties     Galerkin method     polynomial chaos approach     semi-analytical approach    

Build orientation determination of multi-feature mechanical parts in selective laser melting via multi-objective decision making

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0737-8

摘要: Selective laser melting (SLM) is a unique additive manufacturing (AM) category that can be used to manufacture mechanical parts. It has been widely used in aerospace and automotive using metal or alloy powder. The build orientation is crucial in AM because it affects the as-built part, including its part accuracy, surface roughness, support structure, and build time and cost. A mechanical part is usually composed of multiple surface features. The surface features carry the production and design knowledge, which can be utilized in SLM fabrication. This study proposes a method to determine the build orientation of multi-feature mechanical parts (MFMPs) in SLM. First, the surface features of an MFMP are recognized and grouped for formulating the particular optimization objectives. Second, the estimation models of involved optimization objectives are established, and a set of alternative build orientations (ABOs) is further obtained by many-objective optimization. Lastly, a multi-objective decision making method integrated by the technique for order of preference by similarity to the ideal solution and cosine similarity measure is presented to select an optimal build orientation from those ABOs. The weights of the feature groups and considered objectives are achieved by a fuzzy analytical hierarchy process. Two case studies are reported to validate the proposed method with numerical results, and the effectiveness comparison is presented. Physical manufacturing is conducted to prove the performance of the proposed method. The measured average sampling surface roughness of the most crucial feature of the bracket in the original orientation and the orientations obtained by the weighted sum model and the proposed method are 15.82, 10.84, and 10.62 μm, respectively. The numerical and physical validation results demonstrate that the proposed method is desirable to determine the build orientations of MFMPs with competitive results in SLM.

关键词: selective laser melting (SLM)     build orientation determination     multi-feature mechanical part (MFMP)     fuzzy analytical hierarchy process     multi-objective decision making (MODM)    

Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

《环境科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 267-273 doi: 10.1007/s11783-008-0058-0

摘要: One of the key challenges in the total maximum daily load (TMDL) development process is how to define the critical condition for a receiving waterbody. The main concern in using a continuous simulation approach is the absence of any guarantee that the most critical condition will be captured during the selected representative hydrologic period, given the scarcity of long-term continuous data. The objectives of this paper are to clearly address the critical condition in the TMDL development process and to compare continuous and event-based approaches in defining critical condition during TMDL development for a waterbody impacted by both point and nonpoint source pollution. A practical, event-based critical flow-storm (CFS) approach was developed to explicitly addresses the critical condition as a combination of a low stream flow and a storm event of a selected magnitude, both having certain frequencies of occurrence. This paper illustrated the CFS concept and provided its theoretical basis using a derived analytical conceptual model. The CFS approach clearly defined a critical condition, obtained reasonable results and could be considered as an alternative method in TMDL development.

关键词: representative hydrologic     occurrence     simulation approach     scarcity     alternative    

End-of-pipe or process-integrated: evidence from LMDI decomposition of China’s SO

Pingdan ZHANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 867-874 doi: 10.1007/s11783-013-0541-0

摘要: In this study, reduction in sulfur dioxide (SO ) emission is decomposed into three parts: source prevention, process control and end-of-pipe treatment, using the Logarithmic Mean Divisia Index method (LMDI). Source prevention and process control are defined as process-integrated treatment. It is found that from 2001 to 2010 the reduction of SO emission density in China was mainly contributed by end-of-pipe treatment. From the 10th Five Year Plan (FYP) period (2001–2005) to the 11th FYP period (2006–2010), the Chinese government has attempted to enhance process-integrated treatment. However, given its initial effort, the effect is limited compared with that of the end-of-pipe treatment. The effectiveness of environmental regulation and technology in the reduction of SO density in 30 provinces (municipality/autonomous regions) from 2001 to 2010 is also investigated. This implies that environmental regulation and technology promote process control and end-of-pipe treatment significantly, but does not influence source prevention. Furthermore, environmental technology will only take effect under the circumstances of stringent environmental regulation. Therefore, to fulfill the whole process treatment, environmental regulation should be strengthened and environmental technology upgraded at the same time.

关键词: end-of-pipe     process-integrated     Logarithmic Mean Divisia Index method (LMDI)     environmental regulation     environmental technology    

δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1414-6

摘要:

• Challenges in sampling of NH3 sources for d15N analysis are highlighted.

关键词: Aerosol ammonium     Atmospheric gaseous ammonia     Isotope fingerprinting     Isotope-based source apportionment     Ammonia gas-to-particle conversion    

Comprehensive health condition assessment on partial sewers in a southern Chinese city based on fuzzy mathematic methods

Lili GAN, Jiane ZUO, Yajiao WANG, Thong Soon LOW, Kaijun WANG

《环境科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 144-150 doi: 10.1007/s11783-013-0554-8

摘要: A self-developed sewer health assessment system using the fuzzy comprehensive evaluation and analytical hierarchy process was applied to give a comprehensive health condition evaluation on part of the local sewers in a southern Chinese city based on the sewer video data collected by a sewer inspection closed circuit television (CCTV) robot. Aside from the overall condition evaluation, the structure, function, and stability status of the sewer were also analyzed using the method. A comprehensive index was proposed to give the overall health condition of pipes with different defects, and , , and were used to quantify the defects affecting the tightness, stability, and function of the pipe, respectively. Results show that 48% of the inspected pipes were in good condition (0< <0.25), and about 33% of the sewer pipes analyzed were categorized to be at severe or urgent condition levels ( >0.5), although most of the pipes were installed only within five years. Frequent sedimentation affects the function of the sewer, and deformation and joint damage affect the structure of the sewer.

关键词: sewer     health condition assessment     analytical hierarchy process     fuzzy comprehensive evaluation     fuzzy mathematic method    

RePizer:一种软件需求排序架构 Article

Saif Ur Rehman KHAN,Sai Peck LEE,Mohammad DABBAGH1,Muhammad TAHIR,Muzafar KHAN,Muhammad ARIF

《信息与电子工程前沿(英文)》 2016年 第17卷 第8期   页码 750-765 doi: 10.1631/FITEE.1500162

摘要: 基于RePizer架构,采用已有的两种需求排序技术:计划博弈(planning game, PG)和层级分析(analytical hierarchy process, AHP),分别比较各自的预期准确度和易用程度

关键词: 软件需求;需求排序技术;排序架构;计划博弈;层级分析    

标题 作者 时间 类型 操作

Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infraredspectroscopy: Implications for enabling cell culture process analytical technology?

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

期刊论文

Evaluating and structuring indicators for wetland assessment

Xuehua LIU, Yan SUN,

期刊论文

Advances in the slurry reactor technology of the anthraquinone process for H

Hongbo Li, Bo Zheng, Zhiyong Pan, Baoning Zong, Minghua Qiao

期刊论文

Computer aided process planning system based on workflow technology and integrated bill of material tree

LU Chun-guang, MENG Li-li

期刊论文

长江堤防安全评价的理论 方法和实现策略

李青云,张建民

期刊论文

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

Junying CHU, Hao WANG, Can WANG

期刊论文

Lightweight design of an electric bus body structure with analytical target cascading

期刊论文

Improved analytical model for residual stress prediction in orthogonal cutting

null

期刊论文

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

期刊论文

Build orientation determination of multi-feature mechanical parts in selective laser melting via multi-objective decision making

期刊论文

Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

期刊论文

End-of-pipe or process-integrated: evidence from LMDI decomposition of China’s SO

Pingdan ZHANG

期刊论文

δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

期刊论文

Comprehensive health condition assessment on partial sewers in a southern Chinese city based on fuzzy mathematic methods

Lili GAN, Jiane ZUO, Yajiao WANG, Thong Soon LOW, Kaijun WANG

期刊论文

RePizer:一种软件需求排序架构

Saif Ur Rehman KHAN,Sai Peck LEE,Mohammad DABBAGH1,Muhammad TAHIR,Muzafar KHAN,Muhammad ARIF

期刊论文