Stainless steel (SS) and Titanium alloy (Ti) are the most commonly used materials in many industrial fields such as the automotive and aerospace industry. Stainless steel has good corrosion resistance and titanium alloy has an extremely lightweight characteristic. The combination of both materials has become a tremendous innovation in the industrial sector. Resistance spot welding which has commonly applied in many industrial fields is a good consideration to join these two dissimilar materials due to the high efficiency that could be achieved by using this method. However, the way of joining these dissimilar materials should be carefully considered due to the significant difference in mechanical properties between SS and Ti. In the present study, 3 mm of SS316L and Ti6Al4V sheets were joint under the resistance spot welding method with an aluminum interlayer. The optimized welding parameters were provided under the Taguchi method L9 orthogonal array along with the mechanical properties’ investigation. The optimum welding parameters were 11 kA of weld current, 30 Cycles of welding time, and 5 kN of electrode force which produced 8.83 kN tensile-shear load of the joint. The mechanical structure analysis shows the different morphology between stainless steel and titanium interfaces and the intermetallic compound layer was formed on the SS/Al and Al/Ti interfaces. The EDX analysis shows the atomic diffusion-reaction on the application of aluminum as an interlayer on the SS/Ti joint.

As a country surrounded by the ocean, Indonesia is categorized as a country that has marine potential. The fishermen communities’ economy depends on ocean. However, the fishermen communities live below the poverty line and their average income is less than regional minimum wage. In conjunction with the issue, this study seeks to investigate the factors affecting the income of fishermen communities and right decision to fishermen in covering with welfare insurance in Cirebon, Indonesia. The quantitative study is designed using cross-sectional approach. The data collected by applying random sampling with open-ended questions and interview. A total of 100 fishermen’s have participated in this study. The study used some factors in measuring the fishermen community income, namely coastal environment condition, fish catching technology and location, operational capital, climate (season) condition, fishermen’s age, fishermen’s education, and fishing experience. The data are analyzed using the multinomial logistic regression model by assisting the statistical software, i.e., SPSS-23. The results show that coastal environment condition, fish catching technology and location, operational capital, climate (season) condition, fishermen’s age, fishermen’s education, and fishing experience have significant effects on fishermen income. Interestingly, the factor of coastal environment condition and climate (season) condition have significant negative effects on fishermen income. In conclusion, this study identified that two important factors reduced the welfare level of fishermen (via income). Also, in line with that things, the right decision which can provide to support and assist the fishermen community was by providing the welfare insurance. It is purposely to give them the protection from various risks faced by fishermen.

This paper presents a review of clustering and mathematical programming methods and their impacts on cell forming (CF) and scheduling problems. In-depth analysis is carried out by reviewing 105 dominant research papers from 1972 to 2017 available in the literature. Advantages, limitations and drawbacks of 11 clustering methods in addition to 8 meta-heuristics are also discussed. The domains of studied methods include cell forming, material transferring, voids, exceptional elements, bottleneck machines and uncertain product demands. Since most of the studied models are NP-hard, in each section of this research, a deep research on heuristics and metaheuristics beside the exact methods are provided. Outcomes of this work could determine some existing gaps in the knowledge base and provide directives for objectives of this research as well as future research which would help in clarifying many related questions in cellular manufacturing systems (CMS).

Rotating shafts have a vast application in various industries especially in the aerospace industry such as engines, compressors and turbines. The researchers have performed considerable efforts on the rotating shafts’ dynamic behavior because of their sensitivity to the rotor specifications and different parameters such as supports. In this paper by employing a pipe elbow element, an especial finite element formulation is derived to investigate dynamic behavior of rotating shaft in the presence of support clearance. The proposed element consists of four nodes with twenty-four degrees of freedom, which also accounts for the shear and gyroscopic effects. Within a finite element analysis framework, the focus of the paper is proposing a formulation to account for the dynamic behavior of a rotating shaft with much less number of elements. The element is implemented in a finite element code and then is used to model and analyze some rotating shaft examples. In order to verify the developed formulation, results are compared with those obtained from other schemes reported in the literature.

In a decision-making environment related to risk, there are four basic circumstances, namely certainty, risk, uncertainty and conflict. The dynamics of the strategic environment in Southeast Asia cannot be separated from the movement of the development of the Islamic State (IS). The terror threat in Southeast Asia is currently divided into different generations of terror, namely the threat of the Al-Qaeda terror network and the threat of the ISIS terror network. This study aims to analyze and identify the risk value of the development of the Islamic State network in Southeast Asia using the Borda and TOPSIS methods. The Borda method is used to give weight to the criteria related to risk analysis. The TOPSIS method is used to provide a criteria-based risk score. This research is limited to the Southeast Asia region with 4 (four) major countries, namely Indonesia, Malaysia, Thailand, and the Philippines. This research is expected to contribute to control the development of Islamic state networks in the Southeast Asian region. Based on the results of the overall risk analysis, it was found that the Philippines has the highest risk factor value for Islamic State (IS) with a value of 0.550 at level 4 in the High category. Indonesia maintains a risk factor value of 0.307. Thailand has a risk factor value of 0.427. Indonesia and Thailand are at level 3 with the Medium category. Meanwhile, Malaysia has a risk factor value of 0.203 at level 2 in the Low category.

The storage of goods plays a crucial role in warehouse management systems. Although this operation is often considered simple, it is in fact complex, due to the volume of products, the uncertainty in demands, and the rapid customer service response that the market requires. Moreover, the optimization of logistical resources to maintain an efficient operational flow, such as the allocation of storage spaces, often requires complex decisions. In this paper, we analyze academic contributions on the storage location assignment problem published between 2005 and 2017. The literature is classified according to the solution methods, objectives, and related considerations. Suggestions are also provided for future research.

This paper discusses an integrated model of batch production and maintenance scheduling on flow shop with two deteriorating machines producing single item to be delivered at a due date. The model describes the trade-off between production and maintenance costs as the production run length increases on two machines. The objective function of the model is to minimize the total cost consisting of in process and completed part inventory costs, setup costs, preventive & corrective maintenance costs and rework costs on two machines. The step-wise optimization algorithm is developed to solve a mixed integer quadratic programming. Comparison with the practice and the model sensitivity analysis are demonstrated to clarify how the algorithm works.

jective FLP. Generally, quantitative factors are considered as material handling cost, time, etc., and qualitative factors are considered as closeness rating, hazardous movement between the facilities, etc. For solving and optimizing two or more objectives, two methods are available. First is weight approach method and second is non-dominated sorting method. In the former method, suitable weights are given to each objective and combined in a single objective function; while in later method, the objectives are defined separately and by making comparison of the solutions on the non-dominance criteria, best Pareto-optimal solutions are obtained. In this paper, equal area multi-objective FLPs which are formulated as quadratic assignment problem (QAP) are considered and optimized using biogeography based optimization (BBO) algorithm and non-dominated sorting BBO (NSBBO) algorithm. BBO is one of the efficient metaheuristic techniques, developed to solve complex optimization problems. Computational results of BBO algorithm using weight approach illustrate its better performance compared to other methods while solving multi-objective FLPs. Furthermore to obtain Pareto optimal solutions, NSBBO algorithm is implemented.

With the intention of addressing product quality, machine reliability, and acceptable service level issues in real fabrication systems, this paper studies joint effects of stochastic breakdown, backorder of permissible shortage, rework, and scrap on the optimal stock replenishing policy. A decision model is developed to solve the problem, which consists of mathematical modeling, formulations, and optimization method in order to help analyze the problem, derive the system cost function, and find the optimal replenishment cycle length decision. Applicability of the research results are demonstrated by a numerical example. The proposed decision model enables production managers to not only determine the optimal stock replenishing policy, but also reveal individual impact and/or joint effects of stochastic breakdown, defective rate, backorder of allowable shortage, rework, and scrap on the replenishing decision. With such an in-depth study, diverse system characteristics become available for managerial decision-making.

Word of mouth (WOM) advertisement plays an essential role for business development. WOM helps consum-ers become familiar with new products and services, the quality of services and promotes different choices with possibly better features. This paper examines the effect of word of mouth advertisement in medical treatments in Batavia hospital in west Jakarta, Indonesia. The study examines the effects of WOM on patient’s fulfillment, satisfaction and re-admission in this hospital. The study designs a questionnaire and distrib-utes it among some patients who are waiting to receive medical care at this hospital. The survey only concentrates on patience who used the medical treatment for at least two times. Structural equation modeling is used to examine the hypotheses of this survey. The results indicate that WOM could increase the patience’s awareness and positively influence on patience’s choice for getting more treatment.