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F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma

《医学前沿（英文）》 2021年第15卷第6期页码 913-921 doi: 10.1007/s11684-021-0874-1

摘要： Epileptogenic hypothalamic hamartoma is characterized by intractable gelastic seizures. A systematic analysis of the overall brain metabolic pattern in patients with hypothalamic hamartoma (HH) could facilitate the understanding of the epileptic brain network and the associated brain damage effects of HH. In this study, we retrospectively evaluated 27 patients with epileptogenic HH (8 female patients; age, 2–33 years) by using ¹⁸F-fluorodeoxyglucose-positron emission tomography. The correlations among tomography result, seizure type, sex, and structural magnetic resonance imaging were assessed. Whole metabolic patterns and voxel-based morphometry findings were assessed by group analysis with healthy controls. Assessment of the whole metabolic pattern in patients with HH revealed several regional metabolic reductions in the cerebrum and an overall metabolic reduction in the cerebellum. In addition, areas showing hypometabolism in the neocortex were more widely distributed ipsilaterally than contralaterally to the HH. Reductions in glucose metabolism and gray matter volume in the neocortex were predominant ipsilateral to the HH. In conclusion, the glucose hypometabolism pattern in patients with epileptogenic HH involved the neocortex, subcortical regions, and cerebellum. The characteristics of glucose hypometabolism differed across seizure type and sex. Reductions in glucose metabolism and structural changes may be based on different mechanisms, but both are likely to occur ipsilateral to the HH in the neocortex. We hypothesized that the dentato-rubro-thalamic tract and cerebro-ponto-cerebellar tract, which are responsible for intercommunication between the cerebral cortex, subcortical regions, and cerebellar regions, may be involved in a pathway related to seizure propagation, particularly gelastic seizures, in patients with HH.

关键词： hypothalamic hamartoma gelastic seizure fluorodeoxyglucose-positron emission tomography voxel-based morphometry

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Altered white matter microarchitecture in Parkinson’s disease: a voxel-based meta-analysis of diffusion

Xueling Suo, Du Lei, Wenbin Li, Lei Li, Jing Dai, Song Wang, Nannan Li, Lan Cheng, Rong Peng, Graham J Kemp, Qiyong Gong

《医学前沿（英文）》 2021年第15卷第1期页码 125-138 doi: 10.1007/s11684-019-0725-5

摘要： This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson’s disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size–signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with ＜30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.

关键词： Parkinson’s disease diffusion tensor imaging fractional anisotropy meta-analysis anisotropic effect size–signed differential mapping

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Autogenous healing mechanism of cement-based materials

《结构与土木工程前沿（英文）》页码 948-963 doi: 10.1007/s11709-023-0960-3

摘要： Autogenous self-healing is the innate and fundamental repair capability of cement-based materials for healing cracks. Many researchers have investigated factors that influence autogenous healing. However, systematic research on the autogenous healing mechanism of cement-based materials is lacking. The healing process mainly involves a chemical process, including further hydration of unhydrated cement and carbonation of calcium oxide and calcium hydroxide. Hence, the autogenous healing process is influenced by the material constituents of the cement composite and the ambient environment. In this study, different factors influencing the healing process of cement-based materials were investigated. Scanning electron microscopy and optical microscopy were used to examine the autogenous healing mechanism, and the maximum healing capacity was assessed. Furthermore, detailed theoretical analysis and quantitative detection of autogenous healing were conducted. This study provides a valuable reference for developing an improved healing technique for cement-based composites.

关键词： autogenous healing cement-based materials healing mechanism aggregation effect

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Urban design based on public safety-Discussion on safety-based urban design

Kaizhen CAI, Jianguo WANG

《结构与土木工程前沿（英文）》 2009年第3卷第2期页码 219-227 doi: 10.1007/s11709-009-0023-4

摘要： Because of public safety problems in construction of urban surroundings, this paper expounds the necessity of the study on public safety-based urban design in perspective of modern city. It brings forward the concept of safety-based urban design and attempts to explore the basic connotation and contents with framework for studies.

关键词： urban public safety urban design safety-based urban design

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Gradient-based compressive image fusion

Yang CHEN,Zheng QIN

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 227-237 doi: 10.1631/FITEE.1400217

摘要： We present a novel image fusion scheme based on gradient and scrambled block Hadamard ensemble (SBHE) sampling for compressive sensing imaging. First, source images are compressed by compressive sensing, to facilitate the transmission of the sensor. In the fusion phase, the image gradient is calculated to reflect the abundance of its contour information. By compositing the gradient of each image, gradient-based weights are obtained, with which compressive sensing coefficients are achieved. Finally, inverse transformation is applied to the coefficients derived from fusion, and the fused image is obtained. Information entropy (IE), Xydeas’s and Piella’s metrics are applied as non-reference objective metrics to evaluate the fusion quality in line with different fusion schemes. In addition, different image fusion application scenarios are applied to explore the scenario adaptability of the proposed scheme. Simulation results demonstrate that the gradient-based scheme has the best performance, in terms of both subjective judgment and objective metrics. Furthermore, the gradient-based fusion scheme proposed in this paper can be applied in different fusion scenarios.

关键词： Compressive sensing (CS) Image fusion Gradient-based image fusion CS-based image fusion

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Reliability-based design for automobiles in China

ZHANG Yimin

《机械工程前沿（英文）》 2008年第3卷第4期页码 369-374 doi: 10.1007/s11465-008-0064-8

摘要： The level of automobile design and manufacturing is an important sign of leadership in science and technology and economic power. The achievements of theories and methods for reliability-based design of automobiles in China are reviewed. For reliability-based design, the theories and practices, optimization, sensitivity, and robustness are estimated. The techniques of reliability-based design for automobiles are developed. The techniques service to the “hollow” phenomena of kernel technology, product innovative power, and independent development power can be solved.

关键词： reliability-based automobile sensitivity optimization robustness

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Reliability-based robust design optimization of vehicle components, Part I: Theory

Yimin ZHANG

《机械工程前沿（英文）》 2015年第10卷第2期页码 138-144 doi: 10.1007/s11465-015-0333-2

摘要：

The reliability-based design optimization, the reliability sensitivity analysis and robust design method are employed to present a practical and effective approach for reliability-based robust design optimization of vehicle components. A procedure for reliability-based robust design optimization of vehicle components is proposed. Application of the method is illustrated by reliability-based robust design optimization of axle and spring. Numerical results have shown that the proposed method can be trusted to perform reliability-based robust design optimization of vehicle components.

关键词： vehicle components reliability-based design optimization reliability-based sensitivity analysis multi-objective optimization robust design

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Reliability-based robust design optimization of vehicle components, Part II: Case studies

Yimin ZHANG

《机械工程前沿（英文）》 2015年第10卷第2期页码 145-153 doi: 10.1007/s11465-015-0334-1

摘要：

The reliability-based optimization, the reliability-based sensitivity analysis and robust design method are employed to propose an effective approach for reliability-based robust design optimization of vehicle components in Part I. Applications of the method are further discussed for reliability-based robust optimization of vehicle components in this paper. Examples of axles,torsion bar, coil and composite springs are illustrated for numerical investigations. Results have shown the proposed method is an efficient method for reliability-based robust design optimization of vehicle components.

关键词： vehicle axles and springs reliability-based design optimization reliability-based sensitivity analysis multi-objective optimization robust design

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A potentiometric cobalt-based phosphate sensor based on screen-printing technology

Lei ZHU,Xiaohong ZHOU,Hanchang SHI

《环境科学与工程前沿（英文）》 2014年第8卷第6期页码 945-951 doi: 10.1007/s11783-013-0615-z

摘要： A potentiometric cobalt-based screen-printing sensor was fabricated by electroplating cobalt on the surface of a screen-printing electrode as the sensitive layer for the determination of dihydrogenphosphate ( ) in wastewater samples. The electrochemical performance of this sensor was fully examined to determine its detection calibration, detection limit, response time, selectivity, and interference with pH, various ions, and dissolved oxygen (DO). The cobalt-based phosphate sensor showed a phosphate-selective potential response in the range of 10 mol·L to 10 mol·L , yielding a detection limit of 3.16 × 10 mol?L and a slope of -37.51 mV?decade in an acidic solution (pH 4.0) of . DO and pH were found to interfere with sensor responses to phosphate. Ultimately, the performance of the sensor was validated for detecting wastewater samples from the Xiaojiahe Wastewater Treatment Plant against the standard spectrophotometric methods for analysis. The discrepancy between the two methods was generally ±5% (relative standard deviation). Aside from its high selectivity, sensitivity, and stability, which are comparable with conventional bulk Co-wire sensors, the proposed phosphate sensor presents many other advantages, such as low price, compactness, ease of use, and the possibility of integration with other analytical devices, such as flow injectors.

关键词： phosphate cobalt screen-printing technology electroplate wastewater

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Study on affecting factors of collaborative product development based on collaboration hierarchy model

ZHANG Xiaodong, LI Yingzi, ZHANG Zhiqiang

《机械工程前沿（英文）》 2007年第2卷第2期页码 210-213 doi: 10.1007/s11465-007-0036-4

摘要： Aiming at the levels of collaborative degree in web-based product development, a collaboration hierarchy model of this product development is developed in this paper. Based on the model, the affecting factors on collaboration levels are analyzed systematically from many aspects, such as technology, organization and business. A gap analysis method is studied in detail, and is applied in a real project. The application shows that it can solve the diverse problems of collaborative product development effectively, and help enterprises find out the critical factors that affect the collaboration.

关键词： development web-based business collaborative collaboration hierarchy

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Optimal design of steel portal frames based on genetic algorithms

CHEN Yue, HU Kai

《结构与土木工程前沿（英文）》 2008年第2卷第4期页码 318-322 doi: 10.1007/s11709-008-0055-1

摘要： As for the optimal design of steel portal frames, due to both the complexity of cross selections of beams and columns and the discreteness of design variables, it is difficult to obtain satisfactory results by traditional optimization. Based on a set of constraints of the Technical Specification for Light-weighted Steel Portal Frames of China, a genetic algorithm (GA) optimization program for portal frames, written in MATLAB code, was proposed in this paper. The graph user interface (GUI) is also developed for this optimal program, so that it can be used much more conveniently. Finally, some examples illustrate the effectiveness and efficiency of the genetic-algorithm-based optimal program.

关键词： satisfactory genetic-algorithm-based Technical Specification algorithm efficiency

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Optimizing environmental insulation thickness of buildings with CHP-based district heating system based

Yumei ZHANG, Pengfei JIE, Chunhua LIU, Jing LI

《能源前沿（英文）》 2022年第16卷第4期页码 613-628 doi: 10.1007/s11708-020-0700-5

摘要： The increase of insulation thickness (IT) results in the decrease of the heat demand and heat medium temperature. A mathematical model on the optimum environmental insulation thickness (OEIT) for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction. Besides, a case study was conducted based on a residential community with a combined heat and power (CHP)-based district heating system (DHS) in Tianjin, China. Moreover, the effect of IT on heat demand, heat medium temperature, exhaust heat, extracted heat, coal consumption, carbon dioxide (CO ) emissions and sulfur dioxide (SO ) emissions as well as the effect of three types of insulation materials (i.e., expanded polystyrene, rock wool and glass wool) on the OEIT and minimum annual total environmental impact were studied. The results reveal that the optimization model can be used to determine the OEIT. When the OEIT of expanded polystyrene, rock wool and glass wool is used, the annual total environmental impact can be reduced by 84.563%, 83.211%, and 86.104%, respectively. It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

关键词： optimum environmental insulation thickness heat medium temperature energy grade extracted heat exhaust heat

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MAS-based production scheduling system for manufacturing cell-based workshop

CHU Hong-yan, CAO Quan-jun, FEI Ren-yuan

《机械工程前沿（英文）》 2006年第1卷第4期页码 375-380 doi: 10.1007/s11465-006-0043-x

摘要： The task of production scheduling is to determine the detailed machining path, time, machine tool, etc., for every work piece, according to the production objective and constraints. It is also an important part of the manufacturing system. In this paper, the manufacturing cell-based workshop is described and its scheduling system structure is established based on MAS (multi-agent system) technology. Through the negotiation and communication of each agent, the machining path is determined and the machining sequence and start time are calculated by GA (genetics algorithm). The communication among agents uses the CORBA (common object request broker architecture) technology of the OMG (Object Management Group). The CORBA-based architecture of the communication is designed and some interfaces for the communication are listed. For the genetics algorithm, chromosome coding, fitness function, parameters selection, and the basic genetics operation including selection, crossover and aberrance, are described. The scheduling system also can deal with some abnormal conditions, such as machine tool failure and urgent tasks. Finally, two scheduling examples are given.

关键词： negotiation selection multi-agent communication abnormal

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Building information modeling based on intelligent parametric technology

ZENG Xudong, TAN Jie

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 367-370 doi: 10.1007/s11709-007-0049-4

摘要： In order to push the information organization process of the building industry, promote sustainable architectural design and enhance the competitiveness of China’s building industry, the author studies building information modeling (BIM) based on intelligent parametric modeling technology. Building information modeling is a new technology in the field of computer aided architectural design, which contains not only geometric data, but also the great amount of engineering data throughout the lifecycle of a building. The author also compares BIM technology with two-dimensional CAD technology, and demonstrates the advantages and characteristics of intelligent parametric modeling technology. Building information modeling, which is based on intelligent parametric modeling technology, will certainly replace traditional computer aided architectural design and become the new driving force to push forward China s building industry in this information age.

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A review of condition-based maintenance: Its prognostic and operational aspects

Yanrong LI, Shizhe PENG, Yanting LI, Wei JIANG

《工程管理前沿（英文）》 2020年第7卷第3期页码 323-334 doi: 10.1007/s42524-020-0121-5

摘要： Condition-based maintenance (CBM) detects early signs of failure and dictates when maintenance should be performed based on the actual condition of a system. In this paper, we first review some of the recent research on CBM under various physical structures and signal data. Then, we summarize several kinds of prognostic models that use monitoring information to estimate the reliability of complex systems or products. Monitoring information also facilitates operational decisions in production planning, spare parts management, reliability improvement, and prognostics and health management. Finally, we suggest some research opportunities for the reliability and operations management communities to fill the research gap between these two fields.

关键词： condition-based maintenance prognostics operational decision-making reliability