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The purpose of this paper is to discuss the recently developed multi-physics computational model for the conventional Gas Metal Arc Welding (GMAW) joining process that has been upgraded with respect to its predictive capabilities regarding the spatial distribution of the mechanical properties controlling the ballistic limit (i.e. penetration resistance) of the weld.

The original model consists of five modules, each dedicated to handling a specific aspect of the GMAW process, i.e.: electro-dynamics of the welding-gun; radiation-/convection-controlled heat transfer from the electric arc to the workpiece and mass transfer from the filler-metal consumable electrode to the weld; prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; and spatial distribution of the as-welded material mechanical properties. The model is upgraded through the introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance of the armor may become controlled by the (often inferior) ballistic limits of its weld (fusion and heat-affected) zones.

The upgraded GMAW process model is next applied to the case of butt-welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using filler-metal electrodes made of the same material. The predictions of the upgraded GMAW process model pertaining to the spatial distribution of the material microstructure and ballistic-limit-controlling mechanical properties within the MIL A46100 butt-weld are found to be consistent with general expectations and prior observations.

To the authors’ knowledge, the present work is the first reported attempt to establish, using computational modeling, functional relationships between the GMAW process parameters and the mechanical properties controlling the ballistic limit of the resulting weld.

An important and challenging question for air transportation regulators and airport operators is the definition and specification of airport capacity. Annual capacity is used for long-term planning purposes as a degree of available service volume, but it poses several inefficiencies when measuring the true throughput of the system because of seasonal and daily variations of traffic. Instead, airport throughput is calculated or estimated for a short period of time, usually one hour. This brings about a mismatch: air traffic forecasts typically yield annual volumes, whereas capacity is measured on hourly figures. To manage the right balance between airport capacity and demand, annual traffic volumes must be converted into design hour volumes, so that they can be compared with the true throughput of the system. This comparison is a cornerstone in planning new airport infrastructures, as design-period parameters are important for airport planners in anticipating where and when congestion occurs. Although the design hour for airport traffic has historically had a number of definitions, it is necessary to improve the way air traffic design hours are selected. This study aims to provide an empirical analysis of airport capacity and demand, specifically focusing on insights related to air traffic design hours and the relationship between capacity and delay.

By reviewing the empirical relationships between hourly and annual air traffic volumes and between practical capacity and delay at 50 European airports during the period 2004–2021, this paper discusses the problem of defining a suitable peak hour for capacity evaluation purposes. The authors use information from several data sources, including EUROCONTROL, ACI and OAG. This study provides functional links between design hours and annual volumes for different airport clusters. Additionally, the authors appraise different daily traffic distribution patterns and their variation by hour of the day.

The clustering of airports with respect to their capacity, operational and traffic characteristics allows us to discover functional relationships between annual traffic and the percentage of traffic in the design hour. These relationships help the authors to propose empirical methods to derive expected traffic in design hours from annual volumes. The main conclusion is that the percentage of total annual traffic that is concentrated at the design hour maintains a predictable behavior through a “potential” adjustment with respect to the volume of annual traffic. Moreover, the authors provide an experimental link between capacity and delay so that peak hour figures can be related to factors that describe the quality of traffic operations.

The functional relationships between hourly and annual air traffic volumes and between capacity and delay, can be used to properly assess airport expansion projects or to optimize resource allocation tasks. This study offers new evidence on the nature of airport capacity and the dynamics of air traffic design hours and delay.

The purpose of this paper is to analyse and predict the housing prices in Petaling district, Malaysia and its six sub-regions with a set of housing attributes using functional relationship model.

A new multiple unreplicated linear functional relationship model with both the response and explanatory variables are subject to errors is proposed. A total of 41,750 housing transacted records from November 2008 to February 2016 were used in this study. These data were divided into 70% training and 30% testing sets for each of the selected sub-regions. Individual housing price was regressed on nine housing attributes.

The results showed the proposed model has better fitting ability and prediction accuracy as compared to the hedonic model or multiple linear regression. The proposed model achieved at least 20% and 40% of predictions that have less than 5% and 10% deviations from the actual transacted housing prices, respectively. House buyers in these sub-regions showed similar preferences on most of the housing attributes, except for residents in Shah Alam who preferred to stay far away from shopping malls, and leasehold houses in Sri Kembangan are more valuable. From the h-nearest houses indicator, it is concluded that the housing market in Sungai Buloh is the most volatile in Petaling District.

As the data used are the actual housing transaction records in Petaling District, it represents only a segment of Malaysian urban population. The result will not be generalized to the entire Malaysian population.

This study is expected to provide insights to policymakers, property developers and investors to understand the volatility of the housing market and the influence of determinants in different sub-regions. The potential house buyers could also use the model to determine if a house is overpriced.

This study introduces measurement errors into the housing attributes to provide a more reliable analysis tool for the housing market. This study is the first housing research in Malaysia that used a large number of actual housing transaction records. Previous studies relied on small survey samples.

The purpose of this paper is to investigate the underlying reciprocity mechanism which governs the relationship between employer and employee at their workplaces in a perspective whereby intrinsic and extrinsic factors of job satisfaction are considered as proxy to organizational offerings, while multi overall job satisfaction and dimensional organizational commitment as employee’ attitudinal reaction to the organizational offerings. Under the aforementioned notion, the present study intends to examine the influence of job characteristics on employees’ attitudes, such as, job satisfaction, organizational commitment and employee’ turnover intentions as psychological response to job characteristics. In a way, the study attempts to insight into how employee’ reciprocate to the perceived obligation toward its organization. The study also aims to supplement the empirical evidence about the competing power of intrinsic and extrinsic factors of job in determining the job satisfaction. Although various studies exhibit positive relationship between job satisfaction and organizational commitment has been consistently reported. However, for the managerial implication, the identification of employee physiological and psychological needs to gauge the understanding of mechanism by which of employee’ reacts to its environment and develop attitude toward their job and organization is imperative. In this context, this study makes a humble attempt to clear the relationships in the perspective of reciprocation between organization and its employees. Thus, this study attempts to illustrate how feeling a need to reciprocate, those who experienced strong satisfaction with job characteristics appear to have had a sense of moral duty to the organization can be helpful in understanding the processes by which organizational inducements exert their influence on other employee attitudes and behaviors. Evidently, while the link between employees’ satisfaction with their job and high organizational commitment, on the one hand, and low intentions to leave on the other is fairly straightforward, yet there in need to study these variables as exogenous and endogenous to inquire about their causation. Also, the available present literature on the understudy concern genuinely lacks adequate empirical material about the competing power of intrinsic and extrinsic factors of job in determining the job satisfaction as such some author hold that intrinsic characteristic of job better predict job satisfaction while as another set of behavioral scientists found extrinsic job characteristics as prime determinant of job satisfaction compare to the intrinsic worth of their jobs. The present study was conducted in the state of depressed economy where unemployment rate is as high as 194 percent it was found interesting to investigate the about the competing power of intrinsic and extrinsic factors of job in determining the job satisfaction. The present study also attempts to supplement the empirical evidence in this direction.

Since the study use the tenets of situational theories of employee’ attitude which assume that employee’ attitude results from the psychological evaluation of one’s job characteristics or other aspects of the environment in the organization; therefore, the study integrates the job characteristics as the organizational offerings to its employee and employees attitude like job satisfaction, organizational commitment and employee’ turnover intentions as reciprocity reaction to the organizational offerings. The structural equation model was used to frames the intricacy job characteristics, job satisfaction and organizational commitment and employee turnover intentions. Ten job characteristics were identified with which employees experience at the workplace as organizational offerings. These include salary, recognition, co-workers, supervision, organizational policies, promotion, working condition, task requirement, job security and nature of work. Subsequently, these identified facets were divided into intrinsic and extrinsic factors of job satisfaction, and were considering as proxy to the organizational offerings to its employees. These job characteristics were identified during in-depth interviews and discussions with the respondents, while overall job satisfaction, organizational commitment and employees’ turnover intentions were considered as employee’s psychological reactions to the organizational offerings. The sample consists of 654 hospital employees, working at the different hospital across state. In order to ensure the representation of the entire human capital, employees working under different levels of occupational status and different sectors of economy were included in the for the purpose of data collection. The number of employees from each hospital has been selected through proportionate method. Employees from each hospital were selected on the basis of the chit method. Measurement tools Questionnaire method was used to collect the data for the present study. A five-point likert type scale was used for the sake of maintaining uniformity in measuring the variables. All the variables were measured with multiple-item scales, questionnaire item used to measure different constructs in this study are derived from the previously established studies. As such, multidimensional organizational commitment construct was measured using items drawn from Meyer and Allen (1991) scale. Job characteristics and employee’ turnover intentions scale was adapted from the study conducted by Ali Muhammad et al. (2008). The instrument used for the present study has universal application. Therefore the results thus produce are of universal significance. The reliability and validity of measurement tools for the study was established by the confirmatory factor analysis (CFA).

The findings from the study reveal employees’ subjective evaluation to the intrinsic and extrinsic factors of job contribute to the formation of their reciprocal perspective of psychological attitude toward its job and organization characterized as their job satisfaction and organizational commitment. As such, better evaluation of job content and job context by the employees leads to the sense of obligation and commitment toward the organization, hence reduces their intentions to discord organizational membership. The findings also reveal that employees tend to incline their job satisfaction more toward the extrinsic worth of job than the intrinsic worth. While as both, job satisfaction and organizational commitment, explains relatively equal variation in the employees’ turnover intentions. The relatively strong correlation of extrinsic characteristics of job could be attributed to the fact that professionals generally have limited control over extrinsic factors and have high degree of control over intrinsic elements. Therefore, their perceptions of the job are particularly dependent on the degree of satisfaction with the extrinsic factors (Pearson and Seiler, 1983).

Although there are various studies manifested the relationship between job satisfaction, organizational commitment and employee turnover intentions, for all that, the present work is an attempt to deem these relationships in a different panorama to bring more insight in the subject of organizational behavior. In this study, the relationship among the job characteristics, job satisfaction, organizational commitment and employee’ turnover intentions were considered in a perspective of reciprocity norms. The study opens new horizons to the researchers across the globe, whereby organizational and job characteristics are considered as catalyst for the employee’ attitude and can be study and analyze in a functional relationship model. A new regime of paradigm may investigate the functional relationship between employer offerings as an input and employee attitudes as an output, with more emphasis on the organizational equilibrium. Hence, study encompass the managerial implication by gauging the understanding of mechanism by which of employee’ reacts to the workplace environment and develop attitude toward their job and organization. In this way, the propositions expatiated in the present work improves the understanding for the implications of various motivational theories, different organizational theories and human resource management models. Moreover, this work substantiates and provides insight about the competing power of intrinsic and extrinsic job factors on job satisfaction and opens debate for the generalization of Herzberg’s motivation theory.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

The purpose of this study was to bridge the gap between customer’s assessment of service quality dimensions (SERVQUAL model) and the descriptors of training. A model of service quality is SERVQUAL, which measures the discrepancy between customer’s perceptions and expectation on the customer service. The dimensions of service quality here are evaluated from the customer’s point of view. Functional fluency as a model of transactional analysis identifies descriptors of interpersonal communication that helps employees improve their responses. Hence, to provide a clear training need assessment, the dimensions of service quality and descriptors of functional fluency must be mapped accordingly.

The semantic mapping of the dimensions of the service quality with descriptors of the functional fluency model.

Of the five dimensions of the SERVAQUAL model, four are behavioral and are mapped with four descriptors belonging to four different modes of the functional fluency model. The four modes are positive manner in which people can respond to improve service quality.

The implication is the training needs that emerge by bridging the gap between SERVQUAL dimensions and functional fluency model for self-development.

This will provide an organization the training needs analysis for their employees for improving their interpersonal communication on service quality dimensions.

Bridging of the gap between customer’s assessment of service quality dimensions (SERVQUAL model) and the descriptors of training (functional fluency model).

Autogenesis is an abstract theory of living systems and their evolution, recently developed by the authors. It is proposed that replication—an imperfect copying of a functional information, directed by the same information—characterizes the living organization. Autogenesis is the evolution of replicative systems, where replicative information develops, compartments are formed, and eventually an end state is reached. In this paper we introduce a computer model, the aim of which is to show the predicted phases and phenomena of autogenesis in a nontrivial way, and to make the main concepts of the theory more transparent.