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The purpose of this paper is to evaluate the lead‐free solder joint reliability of a variety of surface mount components assembled onto printed circuit boards (PCBs) under a number of different tests.

Lead‐free solder with a composition of Sn96.5‐Ag3.0‐Cu0.5 was used in a surface mount reflow process. Different types of surface mount dummy components with a daisy chain, such as CBGAs, BGAs, PLCCs, CSPs, and QFNs, were assembled onto PCBs. Both the mechanical and thermo‐mechanical reliability of the solder joints were evaluated by several tests. The experiments included package shear, package pull, three‐point bending and accelerated thermal cycling testing for 2,000 cycles. The packages were examined by X‐ray and C‐SAM before the reliability tests were carried out. The maximum load and the corresponding load‐displacement curve were recorded in the mechanical test.

The results from the mechanical tests show the major failure mode is on the copper pad. Weibull analysis shows that the characteristic lives of most packages are between 1,100 and 2,400 cycles. For the CBGA, the characteristic life of 96 cycles is relatively short, due to the serious CTE mismatch. Cross‐section inspection shows failures occur at the solder joint. Copper pad failure is also observed.

This paper provides both the mechanical and thermal‐mechanical reliability of lead‐free solder joints. The experimental data are very useful in the lead‐free SMT industries.

Water heating is one of the major energy‐consuming operations in the lodging sector. The purpose of the current study is to estimate the energy consumed and emission associated with hot water usage, to predict the energy cost required under different hot water systems in hotels; and to create a model for the decision‐making criteria in selecting hot water systems.

A total of 24 hotels, which use heat pumps as their main water heating systems, were investigated. A tailor‐made model for estimating the energy requirement of the water heating system was employed. Comparative studies on the energy consumption and energy costs of various types of water heating systems, including heat pumps, diesel boilers, gas boilers, and electric boilers, were conducted. Moreover, an analytic hierarchy process was used to analyze hoteliers' and lenders' selection criteria for water heating facilities.

The energy output for water heating by heat pumps was estimated at 15 GW in the lodging sector. The use of heat pumps can achieve substantial energy savings and reduction of air pollutants when compared with the energy requirements under conventional boilers. The latter accounts for 13 percent of the hoteliers' total decision weight on choosing water‐heating systems. Whereas the air pollutants generated by gas‐fired boilers are remarkably lower than those emitted in the power plants due to the use of heat pumps. Both bankers and hoteliers consider seriously the energy saving potential of hot water supply by trucks.

Due to the small number of decision‐makers in hotels participating in the analytic hierarchy process, the result can only provide an indication of the overall picture of the selection criteria adopted by hoteliers.

The analysis provides hotel owners and managers with an objective and scientific investigation of the emission prediction and energy cost estimation based on the use of different hot water systems. Hotel operators and owners can use the analytical results as reference for making green purchasing decisions.

The current study, which is based on the operational experiences of existing hotels, is a collaborative work between hospitality industry practitioners and educators. It is also the first of its kind to indicate the emission impact of various types of hotel water heating systems and the perspectives of hoteliers and bankers on these systems.

This study aims to understand the impacts of the Minor Works Control System (MWCS) on the performance of minor works contractors following its implementation in 2011, and specifically the initiatives adopted by minor works contractors in response to the new building control regime. Suggestions are made for the further improvement of the MWCS. Like many Western countries and Asian counterparts, Hong Kong has recently implemented a new building control system (the MWCS), which aims to restructure the building proposal approval process and shift the responsibility for building control from the public to the private sector. The effectiveness of the MWCS has been strongly questioned by the industry and the public.

A mixed method including a questionnaire survey (quantitative) and focus group discussions (qualitative) was adopted to provide an initial evaluation of the impact of the MWCS on practitioners and the industry.

The results suggest that implementation of the new control system has helped increase safety awareness and the technical capacity of minor works contractors. Despite these benefits, registered contractors are encountering challenges under the MWCS, such as manpower arrangement problems and higher business operating costs. Initiatives that include maintaining a sound financial background, an adequate in-house supervisory staff and a safe working environment are considered critical by practitioners to maintain their competitive edge under the new control regime.

This study is one of the first studies in Hong Kong to evaluate the impact of the new building control system. The feedback and suggestions provided by the practitioners and experts during the research provide valuable insights for the government on how to provide support to practitioners under the MWCS to achieve a better built environment in Hong Kong.

While the peer effects of technology adoption are well established, few studies have considered the variation in peer effects resulting from the mutual proximity between leaders and followers and the heterogeneity of farmers' learning technology. This study addresses the gap in the literature by analyzing the peer effects of technology adoption among Chinese farmers.

Drawing on a government-led soil testing and formulated fertilization program, this study uses survey data of farmers from three Chinese provinces to examine the peer effects of technology adoption. This study uses a probit model to examine how mutual proximity influences peer effects and their heterogeneity. Accordingly, farmers were divided into two groups, namely small- and large-scale farmers, and then into leaders or followers depending on whether they were selected by the government as model farmers.

Both small- and large-scale farmers are more likely to use formula fertilizer if their peers do so. However, a large-scale farmer is more likely to adopt formula fertilizer if the average adoption behavior of other large-scale model (leader) farmers is higher, while a small-scale farmer is more likely to adopt formula fertilizer if other small-scale non-model (follower) farmers have higher average adoption behavior. Moreover, the peer effect was weakened by geographic distance among small-scale farmers and by economic distance among large-scale farmers.

This study elucidates the means of optimizing social learning and technology adoption among farmers.

This paper proposes a conceptual framework underpinning the conflicting key elements in analyzing sustainable development (SD) of real estate property and the environment.

The key elements in the framework are the economic, the socio‐environment, the socio‐economic and the legal systems which represent different competing values.

The competing values framework encompasses the development of environmental legislation and other governmental policies towards environmental sustainability of construction activities. The competing values which direct policy‐making are modelled as short term (resource exploitation) versus long term (resource sustainability) and flexibility (freedom in land use/development) versus control (planning and building laws). As people attain harmonious outcome (intra‐ and inter‐group) in arriving at consensus and directions towards “SD” they do so as members of a complex social organism that has multiple group memberships, interests and loyalties.

As loyalties and interests shift, harmony is in transit, and directions of actions and attitudes change as a function of time. The choice of (potentially conflicting) attainable goals towards SD is a consequence of power play amongst stakeholders.

The paper is important in highlighting the main issues in conceptualizing key conflicting elements in the formulation of policies for SD.

A definition of harmony relating to social exchanges and cultural settings with emphasis on dynamic equilibrium is proposed for the formulation of “SD” policies.

Agricultural carbon productivity considers the dual goals of “agricultural economic growth” and “carbon emission reduction”. Improving agricultural carbon productivity is a requirement for promoting green and low-carbon development of agriculture. Agricultural production agglomeration is widespread worldwide, but the relationship between agricultural production agglomeration and agricultural carbon productivity is inconclusive. This paper aims to study the impact of agricultural production agglomeration on agricultural carbon productivity, which is conducive to a better understanding of the relationships among agglomeration, agricultural economic development and carbon emission, better planning of agricultural layout to build a modern agricultural industrial system and achieve the goal of carbon peaking and carbon neutrality.

Based on China's provincial data from 1991 to 2019, this paper uses non-radial directional distance function (NDDF) and Metafrontier Malmquist–Luenberger (MML) productivity index to measure total factor agricultural carbon productivity. Subsequently, using a panel two-way fixed effect model to study the effect and mechanism of agricultural production agglomeration on agricultural carbon productivity, and the two-stage least squares method (IV-2SLS) is used to solve endogeneity. Finally, this paper formulates a moderating effect model from the perspective of the efficiency of agricultural material capital inputs.

The empirical results identify that Chinese provincial agricultural carbon productivity has an overall growth trend and agricultural technological progress is the major source of growth. There is an inverted U-shaped relationship between agricultural production agglomeration and agricultural carbon productivity. The input efficiency of agricultural film, machine and water resources have moderating effects on the inverted U-shaped relationship. Agricultural production agglomeration also promotes agricultural carbon productivity by inhibiting agricultural carbon emissions in addition to affecting agricultural input factors and its internal mechanisms are agricultural green technology progress and rural human capital improvement.

This paper innovatively adopts the NDDF–MML method to measure the total factor agricultural carbon productivity more scientifically and accurately and solves the problems of ignoring group heterogeneity and the shortcomings of traditional productivity measurement in previous studies. This paper also explains the inverted U-shaped relationship between agricultural production agglomeration and agricultural carbon productivity theoretically and empirically. Furthermore, from the perspective of agricultural material capital input efficiency, this paper discusses the moderating effect of input efficiency of fertilizers, pesticides, agricultural film, agricultural machines and water resources on agricultural production agglomeration affecting agricultural carbon productivity and answers the mechanism of carbon emission reduction of agricultural production agglomeration.

The purpose of this paper is to introduce a step‐by‐step implementation framework for lean product development (LPD), from the marketing research on product development process, product design to the launch of final production.

The research approach taken in this paper is built around the primary industry cases, practical approaches and partial solutions available within the existing literature.

The most recent improvement of LPD, from the authors' perspective, focuses on tools and implementation for LPD. In this paper, a detailed step‐by‐step implementation is given after the framework is introduced. Led by value and waste analysis in product development, different tools and techniques which can be used to eliminate wastes were discussed briefly, and then the implementation from Doing the Right Thing to Doing the Right Thing for company transition to lean were proposed elaborately.

Due to time and economic environment limitations, the authors have not covered and implemented this approach in all existing different environments to ensure that it is robust.

The approach described here seeks to overcome other frameworks' weaknesses in terms of the realistic aspect and feasibility, and combines more existing best practice from industry, consultancy and academia into a step‐by‐step framework for the achievement of effective LPD.

Now formed for almost two years, the Brazilian Printed Circuit Association, ABRACI (Associação Brasileira de Circuitos Impressos), held on 17–18 September 1987 at Curitiba its first seminar on printed circuit technology. The association, with 150 members, is going from strength to strength and the 1987 Seminar was attended by 250 persons from several states. Participants included representatives from well known international companies (Du Pont, Degussa, IBM, Unisys, etc.), Government, Universities and local companies. The programme of 16 papers was divided into four sessions: Market, Quality, Manufacturing and SMT. The two‐day event proved too short for the enthusiasm of participants.

The aims of this article are to introduce a modularization framework and a method for the formation of modules.

A methodological framework is presented to guide designers and engineers in the formation and selection of suitable modules in developing customized products. Detailed explanations of the framework are presented theoretically. This framework interacts with different product development participants such as resources, customers' preferences, design architecture for planning, and scheduling a custom‐built product. A new method is proposed with a case example to facilitate the formation of modules.

This paper investigates the potential of the modularization framework, usable for prioritizing the components dependencies and creating required number of modules. It also explains the overall concept, usability and rules/methods for the module formation applied to product design, to allow a greater degree of freedom for the designer, and the opportunity to reduce development time and increase customer satisfaction. A method, based on the rules for modularity concept is proposed within the scope of this paper.

The framework and the method of modularization as illustrated in this article are based on a theoretical hypothesis. Both the approaches require implementing in a real industrial environment in order to generalize their effectiveness, applicability and consistency in the manufacturing arena.

Since product architecture is an important element in determining the value and flexibility of the product development process, the relationship pattern between the architecture and productivity is therefore worthy of careful investigation. The aims of modular framework and rules for modularity are to incorporate design variables and dependency structure with a view to enhancing product development lead time and will contribute to the exploitation of overall bottlenecks of manufacturing systems.

The implementation framework for modular product architecture seems unique as its potential value could be applied in the industrial environment for production flexibility and reducing bottlenecks. Along with the framework, the presented modularity rule or method will contribute to business architecture with a view to providing more reliable operation, easier maintenance and faster product development time.

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms⁻¹ and 5 ms⁻¹ are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.