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Lean Product Development—Faster, Better … Cleaner?

Geert Letens

《工程管理前沿(英文)》 2015年 第2卷 第1期   页码 52-59 doi: 10.15302/J-FEM-2015007

摘要: To address this challenge, lean product development has emerged to become the leading improvement methodology for companies toward the creation of a competitive advantage on innovation and technology leadership. While lean product development has its origin in the best practice studies of Japanese car manufacturers such as Toyota, it has been further elaborated in defence and aerospace organizations over the last two decades, and recently empirical evidence has become available for successful introductions in sectors different from the traditionally-studied environments. The primary purpose of this work is to untangle the fuzziness that still surrounds lean product development and to ground the key aspects of lean product development based on insights from six studies published in a special issue of the on this topic. This demonstrates how better and faster product development can be achieved through the integration of lean principles with the best of more traditional new product development (NPD) practices, into a holistic system that can be characterised by value-focused and risk-based decision making, the socio-technical integration of people and process, improved project, pipeline and portfolio management, optimized knowledge management, and the creation of a learning organization. Unfortunately, while the increasing global competition offers the potential to improve the quality of life for many, the spirit of faster, better, and cheaper also threatens to endanger the future of our planet as a whole. As the majority of a product’s social and ecological impacts are committed in the design phase, it, therefore, seems imperative to investigate the integration of lean product development and eco-design principles. As a result, this work also explores the symbiosis of both approaches through the identification of tools and methods that can support the triple bottom-line goals for a sustainable future of life and business.

关键词: lean product development     sustainability engineering     responsible design    

Not asthma, but GERD: case report

WANG Zhonggao

《医学前沿(英文)》 2007年 第1卷 第1期   页码 115-119 doi: 10.1007/s11684-007-0022-6

摘要: Asthma is a disorder of the lungs characterized by increased responsiveness of the airways, as manifested by episodes of wheezing and increased resistance to expiratory airflow because of varying degrees of smooth muscle contraction, edema of the mucosa, and mucus in the lumen of the bronchi and bronchioles. The stimuli vary widely and include antigens, infection, air pollutants, respiratory tract irritants, exercise, and emotional factors. This condition is completely different from distress breathing because of laryngotracheal spasm. One of its causes is the gastric content reflux through the pharynx to the larynx because of gastroesophageal reflux disease (GERD), in addition to the typical human avian flu that may cause immediate suffocation by laryngospasm owing to acute larygotrachitis. A patient suffered from GERD without esophageal symptoms, which was diagnosed and treated as bronchial asthma during his five emergency admissions. The admissions were because of episodic attacks of severe air hunger owing to an extreme throat tightening. The patient was being treated for as long as two years. After the correct diagnosis was made and treatment of laporascopic fundaplication was performed, the longstanding bronchial asthma , after all, completely disappeared. The concept of not asthma, but GERD seems undervalued, unappreciated, even misunderstood among patients with intractable asthma. Therefore, such a case is reported in detail, similar cases are mentioned briefly as well, and a mechanism responsible for GERD-originated larryngo- or laryngotracho-spasm is proposed.

关键词: resistance     mechanism responsible     unappreciated     responsiveness     different    

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

《能源前沿(英文)》 2008年 第2卷 第2期   页码 121-128 doi: 10.1007/s11708-008-0033-2

摘要: As a barrier to compartmentalize cells, membranes form the interface between a cell and its surroundings. The essential function of a membrane is to maintain a relatively stable environment in the cell, exchange substances selectively and transfer energy and information continually from the outside. It is intriguing that above the phase transition temperature, the membrane lipid molecule will have three modes–lateral diffusion, rotational movement and flip-flop activity. These thermodynamic processes are vital to cell existence, growth, division, differentiation and are also responsible for hundreds of thousands of phenomena in life. Previously, species transport across the membrane was interpreted mainly from a phenomenological view using a lumped system model. Therefore, detailed flow processes occurred in the membrane domain and clues related to life mechanism were not sufficiently tackled. Such important issues can be clarified by modeling nano scale thermal hydrodynamics over the gap space of a cell membrane. Previously observed complex membrane behaviors will be shown in this paper and explained by the thermally induced fluidic convections inside the membrane. A correlation between nano scale hydrodynamics, non-equilibrium thermodynamics and cell membrane activities is set up. The disclosed mechanisms are expected to provide a new viewpoint on the interaction between intracellular and extracellular processes through the membrane.

关键词: responsible     phenomenological     phenomena     modes–lateral diffusion     differentiation    

Relationship between expression of hepatocyte grow factor and apoptosis of trophoblasts in hypertensive disorder complicating pregnancy

OUYANG Shan, ZHANG Qinghua, QIAO Fuyuan

《医学前沿(英文)》 2007年 第1卷 第4期   页码 386-389 doi: 10.1007/s11684-007-0075-6

摘要: The aim of this study was to investigate the expression of hepatocyte growth factor (HGF) and Fas in placentas of uncomplicated pregnant women and those with hypertensive disorder complicating pregnancy (HDCP), and elucidate the possible relationship between HGF and apoptosis of trophoblasts. Reverse transcription-polymerase chain reaction (RT-PCR) was undertaken to examine the concentration of HGF mRNA and Fas mRNA obtained from 34 cases of HDCP and 30 cases of uncomplicated pregnancy. The expression of HGF mRNA in mild preeclampsia, severe preeclampsia and eclampsia cases was significantly lower than that in the uncomplicated cases (0.43±0.12, 0.38±0.09, 0.19±0.17 versus 0.67±0.19, <0.05), while the expression of Fas mRNA in mild preeclampsia, severe preeclampsia and eclampisa cases was significantly higher than that in the uncomplicated cases (1.58±0.26, 2.96±0.14, 5.98±1.17 versus 1.01±0.36, <0.05). For HGF mRNA and Fas mRNA, there was no difference between gestational hypertension cases and control cases. Decreased HGF mRNA or increased Fas mRNA was found along with the progress of HDCP. Negative correlation was found between the expressions of HGF and Fas. These results indicate that HGF inhibits the apoptosis mediated by Fas, and the reduced expression of HGF in HDCP may be responsible for the apoptosis of trophoblasts.

关键词: pregnancy     concentration     possible relationship     responsible     hepatocyte    

Construction engineering management culture shift: Is the lowest tender offer dead?

Eric SCHEEPBOUWER, Douglas D. GRANSBERG, Carla Lopez del PUERTO

《工程管理前沿(英文)》 2017年 第4卷 第1期   页码 49-57 doi: 10.15302/J-FEM-2017014

摘要: The procurement of public construction projects must walk a fine line between the corruption of state officials and collusion of contractors. The method of awarding projects to the lowest responsible tenderer was originally implemented to guard against corruption of state officials. However, an investigation of the construction industry in the Canadian province of Quebec showed that lowest-tender-offer procurement gave rise to collusion of companies tendering for the contracts. Alternatively, best-value procurement has been used for decades, but here problems arise owing to the necessity of subjective judging of measures other than price to compare bids, giving rise to time- and money-consuming protests. The paper proposes a compelling argument that the construction engineering management (CEM) culture should refocus its efforts on enhancing project cost certainty rather than merely searching for means to design a project in a manner that produces the lowest initial cost, and awards the construction to the lowest tender offer that focuses on cost savings during the project development and delivery process. The difference in the two approaches is subtle but extremely important. To make the transition, the engineering management tools must be advanced to the next level. This means that all project control tools for managing cost, schedule, and technical scope must be transformed from working in the deterministic mode to the stochastic mode, thus making the probability of completing the project within or below its official budget the primary decision criterion. To do so, CEMs must accept that there is a benefit in paying more for an alternative that increases cost certainty for the entire project. The authors of this paper hope that it will provide the grist for a more general dialog across all industry sectors where engineering management is practiced.

关键词: cost certainty     lowest responsible bid     best value     public procurement     construction engineering management culture    

Reliability design method for steam turbine blades

SHI Jinyuan

《能源前沿(英文)》 2008年 第2卷 第4期   页码 363-368 doi: 10.1007/s11708-008-0073-7

摘要: Based on theories of probability and statistics, and taking static stresses, dynamic stresses, endurance strength, safety ratios, vibration frequencies and exciting force frequencies of blades as random variables, a reliability design method for steam turbine blades is presented. The purport and calculation method for blade reliability are expounded. The distribution parameters of random variables are determined after analysis and numerical calculation of test data. The fatigue strength and the vibration design reliability of turbine blades are determined with the aid of a probabilistic design method and by interference models for stress distribution and strength distribution. Some blade reliability design calculation formulas for a dynamic stress design method, a safety ratio design method for fatigue strength, and a vibration reliability design method for the first and second types of tuned blades and a packet of blades on a disk connected closely, are given together with some practical examples. With these methods, the design reliability of steam turbine blades can be guaranteed in the design stage. This research may provide some scientific basis for reliability design of steam turbine blades.

关键词: design reliability     force     probability     purport     reliability design    

Assembly design system based on engineering connection

Wensheng YIN

《机械工程前沿(英文)》 2016年 第11卷 第4期   页码 423-432 doi: 10.1007/s11465-016-0382-1

摘要:

An assembly design system is an important part of computer-aided design systems, which are important tools for realizing product concept design. The traditional assembly design system does not record the connection information of production on the engineering layer; consequently, the upstream design idea cannot be fully used in the downstream design. An assembly design model based on the relationship of engineering connection is presented. In this model, all nodes are divided into two categories: The component and the connection. Moreover, the product is constructed on the basis of the connection relationship of the components. The model is an And/Or graph and has the ability to record all assembly schemes. This model records only the connection information that has engineering application value in the product design. In addition, this model can significantly reduce the number of combinations, and is very favorable for the assembly sequence planning in the downstream. The system contains a connection knowledge system that can be mapped to the connection node, and the connection knowledge obtained in practice can be returned to the knowledge system. Finally, VC++6.0 is used to develop a prototype system called Connect-based Assembly Planning (CAP). The relationship between the CAP system and the commercial assembly design system is also established.

关键词: product design     assembly design     engineering connection     assembly sequence planning    

设计科学的争论和设计竞争力

谢友柏

《中国工程科学》 2014年 第16卷 第8期   页码 4-13

摘要:

本文回溯了19 世纪末以来西方关于设计科学的争论,探讨在前工业设计时期、工业设计时期和后工业设计时期中关于设计认知和理念的变化,特别是它们在整个工业设计时期中随同满足物质需求产品生产能力增长而发生的转变。事实表明,当产能不满足物质需求时,工业生产是以规模竞争优先;而当规模发展到极端而导致产能过剩并引发许多社会问题时,工业生产就转向创新竞争。竞争模式改变导致设计认知和理念的变化:从保证大规模物质生产、符合物质演变规律,即理性的系统化的设计,到满足人们对新的和美好生活的追求,并同时满足物质需求、精神需求和社会需求统一的由创意引领的设计。哪一个设计能使创新成功,取决于竞争,不仅仅是市场竞争,而且是在社会发展中的竞争。现在不是会不会设计的问题,而是设计有没有竞争力。中国正处在经济增长方式转变的关键时期,推动设计科学的研究,认识这些变化非常重要。本文提出了“竞争性设计”和“继承性设计”的概念,并将后工业设计时期称为竞争性设计时期。

关键词: 设计     工业设计     设计科学     知识     知识获取    

A comparative review of the state and advancement of Site-Specific Crop Management in the UK and China

Zhenhong LI, James TAYLOR, Lynn FREWER, Chunjiang ZHAO, Guijun YANG, Zhenhai LI, Zhigang LIU, Rachel GAULTON, Daniel WICKS, Hugh MORTIMER, Xiao CHENG, Chaoqing YU, Zhanyi SUN

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 116-136 doi: 10.15302/J-FASE-2018240

摘要:

Precision agriculture, and more specifically Site-Specific Crop Management (SSCM), has been implemented in some form across nearly all agricultural production systems over the past 25 years. Adoption has been greatest in developed agricultural countries. In this review article, the current situation of SSCM adoption and application is investigated from the perspective of a developed (UK) and developing (China) agricultural economy. The current state-of-the art is reviewed with an emphasis on developments in position system technology and satellite-based remote sensing. This is augmented with observations on the differences between the use of SSCM technologies and methodologies in the UK and China and discussion of the opportunities for (and limitations to) increasing SSCM adoption in developing agricultural economies. A particular emphasis is given to the role of socio-demographic factors and the application of responsible research and innovation (RRI) in translating agri-technologies into China and other developing agricultural economies. Several key research and development areas are identified that need to be addressed to facilitate the delivery of SSCM as a holistic service into areas with low precision (PA) agriculture adoption. This has implications for developed as well as developing agricultural economies.

关键词: remote sensing     decision support     responsible research and innovation     digital soil mapping    

Optimal dome design considering member-related design constraints

Tugrul TALASLIOGLU

《结构与土木工程前沿(英文)》 2019年 第13卷 第5期   页码 1150-1170 doi: 10.1007/s11709-019-0543-5

摘要: This study proposes to optimize the design of geometrically nonlinear dome structures. A new Multi-objective Optimization Algorithm named Pareto Archived Genetic Algorithm (PAGA), which has an ability of integrating the nonlinear structural analysis with the provisions of American Petroleum Institute specification is employed to optimize the design of ellipse and sphere-shaped dome configurations. Thus, it is possible to investigate how the qualities of optimal designations vary considering the shape, size, and topology-related design variables. Furthermore, the computing efficiency of PAGA is evaluated considering six multi-objective optimization algorithms and eight quality measuring indicators. It is shown that PAGA has a capability of both exploring an increased number of pareto solutions and predicting a pareto front with a higher convergence degree. Moreover, the inclusion of shape-related design variables leads to a decrease in both the weights of dome structures and their load-carrying capacities. However, the designer easily determines the most requested optimal design through the archiving feature of PAGA. Thus, it is also demonstrated that the proposed optimal design procedure increases the correctness degree in the evaluation of optimal dome designs through the tradeoff analysis. Consequently, PAGA is recommended as an optimization tool for the design optimization of geometrically nonlinear dome structures.

关键词: dome structure     geometric nonlinearity     multi-objective optimization     API RP2A-LRFD    

LARM PKM solutions for torso design in humanoid robots

Marco CECCARELLI

《机械工程前沿(英文)》 2014年 第9卷 第4期   页码 308-316 doi: 10.1007/s11465-014-0318-6

摘要:

Human-like torso features are essential in humanoid robots. In this paper problems for design and operation of solutions for a robotic torso are discussed by referring to experiences and designs that have been developed at Laboratory of Robotics and Mechatronics (LARM) in Cassino, Italy. A new solution is presented with conceptual views as waist-trunk structure that makes a proper partition of the performance for walking and arm operations as sustained by a torso.

关键词: humanoid robots     torso design     parallel manipulators (PKM)     conceptual design    

Structural optimal design of a swing vane compressor

Junjie MA,Xiang CHEN,Zongchang QU

《能源前沿(英文)》 2019年 第13卷 第4期   页码 764-769 doi: 10.1007/s11708-016-0449-z

摘要: In this paper, a novel swing vane rotary compressor (SVC) was introduced, which had significant advantages—simple mechanism, reduced frictional loss, reliable operation, and a comparatively higher compression ratio. Based on the swing vane compressor geometry model, thermodynamic model and kinetic model, the mathematical model of optimum design was established, and further theoretical and experimental studies were conducted. The length of the cylinder, radius of the rotor and cylinder were defined as design variables and the reciprocal of EER as objective function. The complex optimization method was adopted to study the structure of the swing vane compressor. The theoretical model could provide an effective method for predicting compressor performance, which would also contribute to structural optimization of the SVC. The study shows that the friction loss of the compressor are greatly reduced by optimized design in a given initial value, and the EER increased by 8.55%.

关键词: swing vane compressor     simulation     optimization design    

Ranking of design scenarios of TMD for seismically excited structures using TOPSIS

Sadegh ETEDALI

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1372-1386 doi: 10.1007/s11709-020-0671-y

摘要: In this paper, design scenarios of a tuned mass damper (TMD) for seismically excited structures are ranked. Accordingly, 10 design scenarios in two cases, namely unconstrained and constrained for the maximum TMD, are considered in this study. A free search of the TMD parameters is performed using a particle swarm optimization (PSO) algorithm for optimum tuning of TMD parameters. Furthermore, nine criteria are adopted with respect to functional, operational, and economic views. A technique for order performance by similarity to ideal solution (TOPSIS) is utilized for ranking the adopted design scenarios of TMD. Numerical studies are conducted on a 10-story building equipped with TMD. Simulation results indicate that the minimization of the maximum story displacement is the optimum design scenario of TMD for the seismic-excited structure in the unconstrained case for the maximum TMD stroke. Furthermore, H of the displacement vector of the structure exhibited optimum ranking among the adopted design scenarios in the constrained case for the maximum TMD stroke. The findings of this study can be useful and important in the optimum design of TMD parameters with respect to functional, operational, and economic perspectives.

关键词: seismic-excited building     TMD     optimum design     PSO     design scenario     TOPSIS    

Mechanical design, modeling, and identification for a novel antagonistic variable stiffness dexterous

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0691-5

摘要: This study traces the development of dexterous hand research and proposes a novel antagonistic variable stiffness dexterous finger mechanism to improve the safety of dexterous hand in unpredictable environments, such as unstructured or man-made operational errors through comprehensive consideration of cost, accuracy, manufacturing, and application. Based on the concept of mechanical passive compliance, which is widely implemented in robots for interactions, a finger is dedicated to improving mechanical robustness. The finger mechanism not only achieves passive compliance against physical impacts, but also implements the variable stiffness actuator principle in a compact finger without adding supererogatory actuators. It achieves finger stiffness adjustability according to the biologically inspired stiffness variation principle of discarding some mobilities to adjust stiffness. The mechanical design of the finger and its stiffness adjusting methods are elaborated. The stiffness characteristics of the finger joint and the actuation unit are analyzed. Experimental results of the finger joint stiffness identification and finger impact tests under different finger stiffness presets are provided to verify the validity of the model. Fingers have been experimentally proven to be robust against physical impacts. Moreover, the experimental part verifies that fingers have good power, grasping, and manipulation performance.

关键词: multifingered hand     mechanism design     robot safety     variable stiffness actuator    

On the improvement design of dynamic characteristics for the roller follower of a variable-speed plate

Hui Ching FAN, Hong Sen YAN

《机械工程前沿(英文)》 2012年 第7卷 第1期   页码 5-15 doi: 10.1007/s11465-012-0310-y

摘要:

Without modifying the cam contour, a cam mechanism with a variable input speed trajectory offers an alternative solution to flexibly achieve kinematic and dynamic characteristics, and then decrease the follower’s residual vibration. Firstly, the speed trajectory of cam is derived by employing Bezier curve, and motion continuity conditions are investigated. Then the motion characteristics between the plate cam and its roller follower are derived. To analyze the residual vibration, a single degree of freedom dynamic model of the elastic cam-follower system is introduced. Based on the motion equation derived from the dynamic model, the residual vibration of the follower is yielded. The design procedure to improve the kinematic and dynamic motion characteristics is presented and two design examples with discussions are provided. Finally, the simulations of the kinematic and dynamic models by ADAMS are carried out and verified that the design models as well as the performances of the mechanism are feasible.

关键词: cam mechanism     variable input speed     kinematic design     dynamic design     optimal design    

标题 作者 时间 类型 操作

Lean Product Development—Faster, Better … Cleaner?

Geert Letens

期刊论文

Not asthma, but GERD: case report

WANG Zhonggao

期刊论文

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

期刊论文

Relationship between expression of hepatocyte grow factor and apoptosis of trophoblasts in hypertensive disorder complicating pregnancy

OUYANG Shan, ZHANG Qinghua, QIAO Fuyuan

期刊论文

Construction engineering management culture shift: Is the lowest tender offer dead?

Eric SCHEEPBOUWER, Douglas D. GRANSBERG, Carla Lopez del PUERTO

期刊论文

Reliability design method for steam turbine blades

SHI Jinyuan

期刊论文

Assembly design system based on engineering connection

Wensheng YIN

期刊论文

设计科学的争论和设计竞争力

谢友柏

期刊论文

A comparative review of the state and advancement of Site-Specific Crop Management in the UK and China

Zhenhong LI, James TAYLOR, Lynn FREWER, Chunjiang ZHAO, Guijun YANG, Zhenhai LI, Zhigang LIU, Rachel GAULTON, Daniel WICKS, Hugh MORTIMER, Xiao CHENG, Chaoqing YU, Zhanyi SUN

期刊论文

Optimal dome design considering member-related design constraints

Tugrul TALASLIOGLU

期刊论文

LARM PKM solutions for torso design in humanoid robots

Marco CECCARELLI

期刊论文

Structural optimal design of a swing vane compressor

Junjie MA,Xiang CHEN,Zongchang QU

期刊论文

Ranking of design scenarios of TMD for seismically excited structures using TOPSIS

Sadegh ETEDALI

期刊论文

Mechanical design, modeling, and identification for a novel antagonistic variable stiffness dexterous

期刊论文

On the improvement design of dynamic characteristics for the roller follower of a variable-speed plate

Hui Ching FAN, Hong Sen YAN

期刊论文