E-commerce as one of the most significant aspects of innovation in business processes is what takes place in companies across the world. The gap between information and communications technology and e-business application is called the digital divide. It is necessary to understand the reasons for the failure of commercial sites. Here the objective is to assess the commercial sites of Iran. Different methods are adopted to evaluate sites and electronic stores. The balanced scorecard is a rarely adopted method of concern to evaluate these sites in Iran. The survey methodology and Delphi technique are applied in building the research tools, which led to the development of a questionnaire. Through applying the BSC approach, the numbers of indicators in each of the four perspectives of BSC were identified. The DEMATEL technique is applied to determine the importance of different perspectives and to identify the causal correlations among the four perspectives. The results generated by SMART PLS graphics, the Structural Equation Modeling software, confirm the adequacy of this proposed model for websites. The findings here indicate that the growth and learning perspective have the greatest impact on the other perspectives while the other perspectives mostly affect the financial perspective.

The battery packs are one of the most vulnerable parts of satellites for damages induced by vibration and shock during launch process. This is due to their considerable weight which increases their susceptibility for structural damage and short connection. Therefore, the related components have to pass successfully ground dynamic and vibration tests in order to verify the dynamic design of such component and ensure the successful performance of a space mission. In this paper, first a new design is presented for a battery pack of a microsatellite and then the verification of designed and manufacturing pack is done by performing some vibration tests based on the European space standard (ECSS). It was shown that the designed battery pack which uses circular or radial type arrangement for the battery cell layout can suitably pass the mechanical vibration tests applied to the pack during the lunch.

Friction drilling is a green hole-making process that zealously utilizes the heat generated from the friction between the rotating conical tool and workpiece to create a bushing without generating chip. The difficult-to-machine materials with unique metallurgical properties have been developed to meet the demands of extreme applications. However, the major challenges of friction drilling on difficult-to-machine materials are the hole diameter accuracy, petal formation and tool wear. In this study, the effects of process parameters such as spindle speed and feed rate on bushing height and shape, hardness and tool wear in friction drilling of titanium alloy Ti-6Al-4V were experimentally investigated using tungsten carbide tool. Optical photographs have also been analyzed for better understanding of the chipless friction drilling process for different parametric settings. Experimental results indicated that the spindle speed has great influences for achieving better bushing formation and prolong the tool life. It was confirmed that the low spindle speed and low feed rate have great influences for achieving better bushing shape and height, prolong tool life and lower hardness that located adjacent to the hole wall. It also was discovered that the low thermal conductivity of Ti-6Al-4V caused to improper increment of frictional heat and surface temperature. This disadvantage leads to unsatisfactory bushing formation. This work demonstrated the performances of chipless friction drilling used on difficult-to-machine material that can offer a great prospective for a new product design and manufacturing.

The nature and complexity of today’s supply chains have predisposed them to various risks, which are described under different terms, including disturbances, uncertainties and riots. Under these conditions, organizations are required to manage their supply chain in a way that is responsive to changes. The purpose of this study is to analyze the relationships between the strategies of coping with disturbances in supply chain networks. This is an applied research and using the research literature, 41 factors are selected for the solutions of coping with risk in supply chain networks. Then, these factors are entered in a questionnaire and presented for some supply chain experts. After that, Interpretative Structural Modeling (ISM) and Fuzzy MICMAC are implemented to rate the solutions of coping with risk in supply chain networks. The results show that the establishment of a supply chain continuity system at the seventh level is the basis of agility in the supply chain. The proper and efficient design of processes in the supply chain network will lead to proper operation in management solutions and appropriate synchronization in the supply chain networks. Using appropriate management solutions in synchronization leads to the integration and proper sharing of information within a supply chain network and between various supply chains and government. Additionally, using the synchrony and integration of supply chain networks, it is possible to design the proper supply chain network and appropriate communication between employees and network elements.

Skill management is a key factor in improving effectiveness of industrial companies, notably their maintenance services. The problem considered in this paper concerns scheduling of maintenance tasks under resource (maintenance teams) constraints. This problem is generally known as unrelated parallel machine scheduling. We consider the problem with a both objectives of minimizing total weighted tardiness (TWT) and number of tardiness tasks. Our interest is focused particularly on solving this problem under skill constraints, which each resource has a skill level. So, we propose a new efficient heuristic to obtain an approximate solution for this NP-hard problem and demonstrate his effectiveness through computational experiments. This heuristic is designed for implementation in a static maintenance scheduling problem (with unequal release dates, processing times and resource skills), while minimizing objective functions aforementioned.

This paper examines the relationship between capital structure and profitability of non-financial companies listed on Vietnam's stock market. The panel data is extracted from financial statements of 488 listed companies between 2013 and 2018. Capital structure discussed is represented by the ratios of short-term liabilities, long-term liabilities and total liabilities to total assets, and profitability is measured by Return on Equity (ROE), Return on Assets (ROA) and Earnings per share (EPS). Firm size, growth rate, liquidity, ratio of fixed assets to total assets are control variables in the study. The Generalized Least Square (GLS) is applied to different models, including ROE, ROA and EPS Model, and tests of autocorrelation, multicollinearity and heteroskedasticity are run to confirm the relationship between capital structure and business performance. The results show that the capital structure of Vietnamese listed non-financial companies is negatively related to their performance. Taking industrial product sectors as the preference sectors, the results show that pharmaceutical and medical, the consumer goods and the public utility industries had a higher relationship between capital structure and firm’s performance (via ROE, ROA, EPS) than industrial product sectors. These evidences are useful new insights to investors, business managers and governmental authorities.

Supplier selection is a complex multi-criteria decision making (MCDM) problem. There are literally various methods for choosing appropriate supplier but there are several criteria involved in complex decision making process. The classical MCDM methods cannot effectively solve real-world problems however fuzzy MCDM methods facilitate the solution fairly and enable the decision-makers to reach accurate decisions in this selection process. In this study, a supplier selection problem is handled, in a firm in automotive industry of Turkey. Fuzzy TOPSIS (Technique for Order Performance by Similarity to Ideal Solution) and generalized Choquet integral are used individually in the solution of the problem.

The aim of this study was to establish the relationship between procurement risk management practices and supply chain performance among mobile phone service providers in Kenya. The study specifically set out to establish the extent to which mobile phone service providers have implemented procurement risk management practices and to determine the relationship between procurement risk management practices and supply chain performance. The study adopted a descriptive study design by collecting data from the four (4) mobile telecommunication companies in Kenya using a self-administered questionnaire. Means, standard deviation, and regression analysis were used to analyze the data collected. The study established that most of the mobile phone service providers in Kenya had implemented procurement risk management practices. It was also clear that there was a very significant relationship between procurement risk management practices and supply chain performance.

This paper describes laboratory tests on twelve simply-supported one-way slabs including four lightweight concrete slabs in this study and previously conducted experiments on eight self-compacting reinforced concrete slabs subjected to loading at the age of 14 days. All slab were identical by dimensions of 3.8 m long supported on 3.5 m span, 400 mm wide, and 161 mm deep with 4N12 bars at an effective depth of 136 mm providing a reinforcement ratio of 0.008. After seven days moist-curing, the specimens were removed from the formworks and subjected to different values of the uniformly distributed loading including the self-weight of slabs. The mid-span deflection of slabs was recorded immediately after putting the loading blocks on the slabs. Despite close values of the compressive strength of the mixtures, the obtained results validate the effect of the concrete type on the instantaneous deflection of slabs. A wide range of existing models of the effective stiffness of reinforced concrete section were investigated to predict the instantaneous deflection of slabs. Majority of the models are developed for conventional concrete. Comparing the predicted and experimental results of mid-span deflection confirmed that the existing models are inadequate for lightly reinforced specimens such as slabs. New models are proposed and verified to predict the effective moment of inertia in the slabs with and without fiber reinforcing concretes.

Global competition pressures have forced manufactures to adapt their productive capabilities. In order to satisfy the ever-changing market demands many organizations adopted flexible resources capable of executing several products with different performance criteria. The unrelated parallel-machines makespan minimization problem (Rm||Cmax) is known to be NP-hard or too complex to be solved exactly. In the heuristics used for this problem, the MCT (Minimum Completion Time), which is the base for several others, allocates tasks in a random like order to the minimum completion time machine. This paper proposes an ordered approach to the MCT heuristic. MOMCT (Modified Ordered Minimum Completion Time) will order tasks in accordance to the MS index, which represents the mean difference of the completion time on each machine and the one on the minimum completion time machine. The computational study demonstrates the improved performance of MOMCT over the MCT heuristic.