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The purpose of this paper is to measure the financial risk and optimal capital structure of a corporation.

Irregular disjunctive programming problems arising in firm models and risk management can be solved by the techniques presented in the paper.

Parallel processing and mathematical modeling provide a fruitful basis for solving ultra-scale non-convex general disjunctive programming (GDP) problems, where the computational challenge in direct mixed-integer non-linear programming (MINLP) formulations or single processor algorithms would be insurmountable.

The test is limited to a single firm in an experimental setting. Repeating the test on large sample of firms in future research will indicate the general validity of Monte-Carlo-based VAR estimation.

The authors show that the risk surface of the firm can be approximated by integrated use of accounting logic, corporate finance, mathematical programming, stochastic simulation and parallel processing.

Parallel processing has potential to simplify large-scale MINLP and GDP problems with non-convex, multi-modal and discontinuous parameter generating functions and to solve them faster and more reliably than conventional approaches on single processors.

The contamination on SMT assemblies caused by a number of flux/cleaning variation has been investigated, with several analysis methods used to quantify the contamination. The results from analysis of test printed circuit boards (PCBs) using anion separation, conductivity, ionic contamination measurement, visual and SEM inspection, microsections and surface insulation resistance (SIR) methods were compared. The best cleaning result was observed with the combination of water soluble (WS) solder cream and water cleaning. The best measurement method for cleanliness of PCBs was considered to be SIR measurement. For WS fluxes, the iconic contamination test offers effective measurement of the amount of residues left on the PCBs.

Ageing populations induce needs to adapt existing housing. With ageing, the number of frail old people, who require assistance in daily life, is also increased. Converting existing housing into assisted living enables them to remain in their community while receiving necessary support and care. The purpose is to investigate whether post-war mass housing is spatially appropriate for adaptation into group homes for older people.

The research material is attained from Finland. Spatial requirements for group homes are drawn from 130 units built or renovated during 2000–2015. Spatial characteristics of mass housing are mapped from 105 apartment buildings built in the 1970s. The latter are matched with the former by comparing the connectivity of layouts, sizes of units and the numbers and sizes of individual spaces.

Group homes typically utilize a linear layout, which can easily be created in apartment buildings. Individual spaces of a group home fit apartment buildings effortlessly. Whole group home units mostly prove to be spatially feasible but result in looser dimensioning than is typical in existing units. The mass housing stock can be considered a spatial reserve for adaptation into group homes.

This is the first study to employ a large-scale, multi-case spatial mapping approach to analyse the adaptability properties of mass housing into assisted living. The findings pertain primarily to the Finnish context, but a methodology is presented which can be applied to other countries and also to other spatial functions.

To explore the fusion of dust particles and of polymers in a viscous liquid is the main purpose of this article. Newtonian fluid as a base fluid is considered and the mutual presence of polymers and dusty bodies is investigated. It discusses the steady laminar flow and heat transportation of a polymeric dusty liquid induced by a uniformly heated, penetrable and stretchable surface inside the boundary layer.

The mathematical system incorporates separate equations of energy and momentum for dusty bodies and for fluid. The classical Oldroyd-B model is chosen for exploring polymer presence. For the fluid phase, this model adds another stress to the conservation law of momentum. Appropriate similarity variables are introduced to transform the system of partial differential equations (PDEs) into a system of nonlinear ordinary differential equations (ODEs). The problem is solved by introducing a numerical iterative procedure which turned out to be fastly converging.

Expeditious changes inside the boundary layer cause polymers to deform. No changes outside the boundary layer are noticed on account of polymer stretching. The dependence of heat transfer rate and skin friction on the parameter of polymer concentration and Weissenberg number is analyzed and displayed graphically against interaction parameters for temperature and velocity, dust particles’ mass concentration, Eckert and Prandtl numbers. Combining effects of polymers and dust particles cause skin friction to decrease and heat transfer rate to increase. Increasing values of interaction parameter for velocity, dust particles’ mass concentration and Eckert number reduces the drag coefficient and local Nusselt number. On the other hand, the Prandtl number and interaction parameter of temperature magnify the heat flux at the wall.

This article studies the infinite extensibility of polymers. FENE and FENE-P models can be used to investigate the polymer presence in dusty fluids in the future.

In this article, the authors’ aim is to study the combined presence of polymers and dusty bodies. Keeping the existing literature in view, this type of fusion is not studied yet. Polymer inclusion in a viscous dusty fluid is studied and the behavior of fluid flow and heat transportation is investigated within the boundary layer over a permeable linearly stretching sheet.

The goal of this work is to evaluate the feasibility of soldering tin‐silver‐copper balled BGAs using tin‐lead‐based solder and to investigate the influence of different production parameters on the microstructure of the solder joint.

The soldering of the BGAs was done with various temperature profiles and two conveyor speeds under a nitrogen atmosphere in a full convection oven. One specimen from each temperature/time combination was cross‐sectioned. The cross sections were analysed with optical microscopy, scanning electron microscopy with energy dispersive X‐ray spectroscopy (SEM/EDS) at 30 kV and focused ion beam microscopy (FIB).

The cross sections show a metallurgical bond between the solder and the tin‐silver‐copper balls of the BGA, even at a peak reflow temperature of 210°C. However, the balls alloy only partially with the solder, as the liquidus of tin‐silver‐copper balls is 217°C. As soon as the peak temperature exceeds the liquidus of the ball, the solder is totally dissolved in the material of the ball. A reflow profile with a peak temperature of about 230°C on the BGA gives a homogenous reaction of the solder with the ball with a minimum formation of voids.

The dependence of varying reflow parameters on reliability requires detailed study. Especially the effect of a partially melted ball on the degradation of the solder joint needs to be investigated.

From the findings, it can be said that soldering lead‐free balls with tin‐lead solder is possible. This is useful during the transitional period that the industry is in at the moment. More and more component manufacturers are changing their components to lead‐free, often without notice to the customer. If a production line is still running a tin‐lead process it is essential to know how to process these components with tin‐lead solder.

The purpose of the present study was to review the thermo-mechanical challenges of reflowed lead-free solder joints in surface mount components (SMCs). The topics of the review include challenges in modelling of the reflow soldering process, optimization and the future challenges in the reflow soldering process. Besides, the numerical approach of lead-free solder reliability is also discussed.

Lead-free reflow soldering is one of the most significant processes in the development of surface mount technology, especially toward the miniaturization of the advanced SMCs package. The challenges lead to more complex thermal responses when the PCB assembly passes through the reflow oven. The virtual modelling tools facilitate the modelling and simulation of the lead-free reflow process, which provide more data and clear visualization on the particular process.

With the growing trend of computer power and software capability, the multidisciplinary simulation, such as the temperature and thermal stress of lead-free SMCs, under the influenced of a specific process atmosphere can be provided. A simulation modelling technique for the thermal response and flow field prediction of a reflow process is cost-effective and has greatly helped the engineer to eliminate guesswork. Besides, simulated-based optimization methods of the reflow process have gained popularity because of them being economical and have reduced time-consumption, and these provide more information compared to the experimental hardware. The advantages and disadvantages of the simulation modelling in the reflow soldering process are also briefly discussed.

This literature review provides the engineers and researchers with a profound understanding of the thermo-mechanical challenges of reflowed lead-free solder joints in SMCs and the challenges of simulation modelling in the reflow process.

The unique challenges in solder joint reliability, and direction of future research in reflow process were identified to clarify the solutions to solve lead-free reliability issues in the electronics manufacturing industry.

This work conducts a comprehensive analysis of how to incorporate resilience and sustainability into capacity expansion strategies for business-to-business (B2B) chemical supply chains. This study aims to guide both researchers and managers on ensuring profitability in B2B chemical supply chains while minimizing environmental impacts, complying with regulations and mitigating disruptions and risks.

A systematic literature review is conducted to analyze the interplay between sustainability and resilience in chemical B2B supply chains, specify the quantitative and qualitative methods used to tackle this challenge and identify the drivers and barriers concerning capacity expansion. In addition, a comprehensive conceptual framework is suggested to outline a compelling research agenda.

The findings emphasize the increasing importance of modeling and resolving decision-making challenges related to sustainable and resilient supply chains, particularly in capital-intensive chemical industries. Yet, there is no standardized strategy for addressing these challenges. The predominant solution methods are heuristic and metaheuristic, and the selection of performance metrics tends to be empirical and tailored to specific cases. The main barriers to achieving sustainability and resilience arise from resource limitations within the supply chain. Conversely, the key drivers of performance focus on enhancing efficiency, competitiveness, cost effectiveness and risk management.

This work offers practitioners a conceptual framework that synthesizes the knowledge and tackles the challenges of designing sustainable and resilient supply chains as well as managing their operations in the context of B2B chemical supply chains. Results provide a practical guide for navigating the complex interplay of sustainability, resilience and chemical supply chain expansion.

The key concepts and dimensions associated with capacity expansion planning for a resilient and sustainable chemical supply chain are identified through structured and comprehensive analyses of existing literature. A conceptual framework is proposed for delineating the intersections among sustainability, resilience and chemical supply chain expansions. This mapping endeavor aims to facilitate a future characterized by the deployment of a nexus of resilience and sustainability in chemical supply chains. To this end, a promising future research agenda is accordingly outlined.

The complexity of business environments often causes organizations to produce several inconsistent views of the same business process (BP), leading to fragmentation. BP view integration attempts to produce an integrated view from different views of the same model, facilitating the management of BP models.

To study the trends of BP view integration, the authors conduct an extensive and systematic literature review to summarize findings since the 1970s. With a starting corpus of 918 documents, this survey draws up a systematic inventory of solutions used in academia and industry. By narrowing it down to 71 articles, the authors discuss in-depth 17 BP integration techniques papers, classifying each solution according to 9 criteria.

The authors' study shows that most view-integration methods (11) utilize annotation-based matching, based on formal merging rules. While most solutions are formalized, only approximately half are validated with a real-world use case scenario. View integration can be applied to areas other than database schema integration and BP view integration.

By summarizing existing knowledge up to June 2021, the authors explore possible future research directions. The authors highlight the application of view integration to the blockchain research area, where stakeholders can have different views on the same blockchain. The authors expect that this study contributes to interdisciplinary research across view integration, namely to the context of blockchain.

This survey serves to pave the way for future trends, where the authors highlight the application of view integration to blockchain research.

Counterfeiting is an increasingly global phenomenon that threatens the economy as a whole and also presents a risk for the consumers. The purpose of this study is to explore moral emotions along with moral awareness and moral judgment with respect to their influence in the consumption of counterfeits.

An online questionnaire was distributed among participants (n = 225) who were asked to respond to a counterfeit purchase scenario.

Results highlight the importance of moral awareness as an essential element of moral decision-making. Also, moral emotions were found to influence moral judgment as well as purchase intention.

A limitation refers to the fact that a scenario was used to evoke participants’ emotional responses. Although the situation was realistic and the majority of the people could very well imagine experiencing the reported scenario, results might change in an actual purchase situation.

This study’s findings may be particularly relevant for authorities and educators who design campaigns to curtail counterfeit consumption, thus seeking to encourage consumers to recognize the several negative consequences that result from counterfeiting behavior.

This is one of the few studies that examine the impact of cognitive and emotional influences in a counterfeit purchase decision. Fighting this problem requires an in-depth understanding of consumers’ motivations and how they feel about engaging in this morally questionable behavior.

Corrosion has been defined as the destruction of metal by chemical or electrochemical reaction with its environment. Methods of corrosion control become more and more important as we are increasingly concerned about conserving our natural resources. For effective control of corrosion, we must have a thorough understanding of its nature and methods of measurements. Little correlation exist between laboratory tests and field performance. Atmospheric exposure tests are required to determine the relative aggressiveness of the environment to a variety of materials that might be selected for use. The development of data for this purpose makes possible a suitable selection of materials. Atmospheric small scale tests can often be made the basis of positive statement about the durability of metals, alloys, metal couples and painted metals on large structures and it needs very careful planning and preparation.