• Journal of Korean Society of Industrial and Systems Engineering
• /
• 제39권3호
• /
• pp.147-155
• /
• 2016

Industry 4.0's goal is the 'Smart Factory' that integrates and controls production process, procurement, distribution and service based on the fundamental technology such as internet of the things, cyber physical system, sensor, etc. Basic requirement for successful promotion of this Industry 4.0 is the large supply of semiconductor. However, company I who produces dicing blades has difficulty to meet the increasing demand and has hard time to increase revenue because its raw material includes high price diamond, and requires very complex and sensitive process for production. Therefore, this study is focused on understanding the problems and presenting optimal plan to increase productivity of dicing blade manufacturing processes. We carried out a study as follows to accomplish the above purposes. First, previous researches were investigated. Second, the bottlenecks in manufacturing processes were identified using simulation tool (Arena 14.3). Third, we calculate investment amount according to added equipments purchase and perform economic analysis according to cost and sales increase. Finally, we derive optimum plan for productivity improvement and analyze its expected effect. To summarize these results as follows : First, daily average blade production volume can be increased two times from 60 ea. to 120 ea. by performing mixing job in the day before. Second, work flow can be smoother due to reduced waiting time if more machines are added to improve setting process. It was found that average waiting time of 23 minutes can be reduced to around 9 minutes from current process. Third, it was found through simulation that the whole processing line can compose smoother production line by performing mixing process in advance, and add setting and sintering machines. In the course of this study, it was found that adding more machines to reduce waiting time is not the best alternative.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권6호
• /
• pp.365-378
• /
• 2020

The study aims to develop concepts originating through empirical research models to build superior competitiveness and optimal performance achievement. Therefore, to bridge these goals, the study addresses several indicators/items as a novelty, namely, entrepreneurship insight factors, market orientation, knowledge-sharing, innovation, managerial capability, product strategy, process and service improvement, resources capability to improve performance and increase competitiveness by empirical model direct, mediating and indirect effect. The total sample in this study is 497 eligible SMEs that partner with go-food in Makassar City. All research samples are the owner or the person in charge of the business; the data collection period is from May to December 2019. Data are collecting using a survey with 64 construct questions, summarized in seven manifest variables. The research method uses quantitative tools, with SMART-PLS as a statistical tool. This study develops sixteen hypotheses; all of the hypotheses are supported both directly, indirectly, and mediated. The study also found that the link based on CCT, RBV, and TAM Theory is the right choice of theories, as the foundation of this study was very reliable and valid. Indeed, all of the grounded methods have implications both in theory and its main application for the business in the online marketplace.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제14권2호
• /
• pp.654-670
• /
• 2020

Workers at construction sites are easily exposed to many dangers and accidents involving falls, tripping, and missteps on stairs. However, researches on construction site monitoring system to prevent work-related injuries are still insufficient. The purpose of this study was to develop a wearable textile pressure insole sensor and examine its effectiveness in managing the real-time safety of construction workers. The sensor was designed based on the principles of parallel capacitance measurement using conductive textile and the monitoring system was developed by C# language. Three separate experiments were carried out for performance evaluation of the proposed sensor: (1) varying the distance between two capacitance plates to examine changes in capacitance charges, (2) repeatedly applying 1 N of pressure for 5,000 times to evaluate consistency, and (3) gradually increasing force by 1 N (from 1 N to 46 N) to test the linearity of the sensor value. Five subjects participated in our pilot test, which examined whether ascending and descending the stairs can be distinguished by our sensor and by weka assessment tool using k-NN algorithm. The 10-fold cross-validation method was used for analysis and the results of accuracy in identifying stair ascending and descending were 87.2% and 90.9%, respectively. By applying our sensor, the type of activity, weight-shifting patterns for balance control, and plantar pressure distribution for postural changes of the construction workers can be detected. The results of this study can be the basis for future sensor-based monitoring device development studies and fall prediction researches for construction workers.

• Korean Journal of Plant Resources
• /
• 제30권2호
• /
• pp.191-213
• /
• 2017

This study was conducted to elucidate the distribution of vascular plants and their value of Mt. Samyeong. The vascular plants that were collected 10 times from October 2013 to July 2015 consisted of a total of 538 taxa; 92 families, 308genera, 466 species, 3 subspecies, 62 varieties and 7 forms. The observed rare plant species as designated by Korea Forest Service were 24 taxa. Endemic species were 25 taxa. 28 taxa were recorded as naturalized plants and their naturalized rate and urban index were noted as 5.3% and 8.7%. Among the surveyed 538 taxa, edible, medicinal, pasturing, ornamental, timber, dye, fiber and industrial plants included 220 taxa, 195 taxa, 167 taxa, 65 taxa, 25 taxa, 8 taxa, 6 taxa and 3taxa, respectively.

• Journal of the Korea Convergence Society
• /
• 제7권6호
• /
• pp.99-104
• /
• 2016

This study is a nonequivalent control group pretest-posttest design to verify the effect of music listening on convergent job stress of experimental group of 40 who are listening to music 10 times and control group of 40 who are taking a rest in fire-fighters. Homogeneity test and distribution of high risk and low risk were analyzed using Chi-test and the effect of listening to music on job stress was analyzed using t-test with SPSS 22.0 program. The experimental group showed a decreased job stress more significantly than the control group. Therefore, job stress intervention program should be developed and practical and systematical approach to reduce the job stress using music listening aggressively should be prepared in the future based on this study's result.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• 제39권12호
• /
• pp.1305-1311
• /
• 2015

A butterfly valve is a type of flow-control device typically used to regulate a fluid flow. This paper presents an estimation of the shape parameter of the Weibull distribution, characteristic life, and $B_{10}$ life for a concentric butterfly valve based on a statistical analysis of the reliability test data taken before and after the valve improvement. The difference in the shape and scale parameters between the existing and improved valves is reviewed using a statistical hypothesis test. The test results indicate that the shape parameter of the improved valve is similar to that of the existing valve, and that the scale parameter of the improved valve is found to have increased. These analysis results are particularly useful for a reliability qualification test and the determination of the service life cycles.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• 제20권9호
• /
• pp.1741-1746
• /
• 2016

Recently, technology using a PC and the personal server efficiently has been highlighted in accordance with the historical background. Solutions for large enterprises and public institutions and PC and personal server management are being commercialized for fee. Paying a fee for PC and personal server management being a burden and commercialized solutions include a function that does not require. In this paper, proposed the PC and personal server management system include monitoring that cpu, hdd, memory, respond speed. It expects to extend the PC and service life is available without charge through the free distribution of the burden. The Development program and application is available for free from the android market and on-line. Server agent program of the proposed system operates based on a single-threaded system. That is low load and the low functional burden on the server.

• Journal of Digital Convergence
• /
• 제16권8호
• /
• pp.89-98
• /
• 2018

The emergence of the mobile commerce market as a new megatrend, mobile shopping is becoming an important distribution channel in the domestic online shopping market. The purpose of this study is to classify shopping values perceived by mobile social commerce users into a utilitarian value and a hedonic value explained and to empirically examine the effects of social commerce characteristics on the purchase intention and shopping values in mobile social commerce. conclusion, this implies that site providers and sellers need to try to supply cheaper and more economical products than those offline and provide the most effective and optimum information and service so sellers and consumers can exchange messages with each other and create meanings.

• Progress in Superconductivity and Cryogenics
• /
• 제19권4호
• /
• pp.1-11
• /
• 2017

This article reviews the recent activities of field testing and application of superconducting fault current limiters (SFCL) based on high-temperature superconductors (HTS). The review particularly focuses on the trends in the field tests in terms of the technical aspects and commercial activities of the SFCLs. Stimulated by the discovery of HTS, numerous research and development activities have been conducted worldwide for SFCLs operating from distribution voltages to transmission voltages. Different types of SFCLs have been developed and field-tested. Consequently, more than 20 field tests and applications have been performed on real grids worldwide while supplying electric power to the customers. These field tests have not only provided the track records of the operation experiences including the problems and maintenance during operation, but also proved their current limiting capabilities against real faults, rendering this new technology highly viable. Through these activities, the following trends in the status of field testing and application are observed. Resistive-type SFCLs with HTS-coated conductors were dominantly used in the most recent field tests. This implies that the resistive type is technically more mature than the other types. Bus-bar coupling and transformer feeders were the major application locations. It is of importance that most of the field applications were conducted as R&D projects. A relevant change from the R&D stage to the application stage is shown as recently deployed SFCLs are expected to be under long-term operation and commercial service. Here, we review the installation of these SFCLs by substation. This review also discusses the recent activities for their commercial applications.

• KIISE Transactions on Computing Practices
• /
• 제23권12호
• /
• pp.670-676
• /
• 2017

Naval combat systems use real-time processing and compositing of collected information to provide the optimal combat capabilities that maximize survival and ensure mission effectiveness. The software for a combat system has dozens to thousands of components depending on the size of the system, and the communication between the components is achieved via DDS. Although the message interface of the combat system is managed through MDMS, an increase in the system size can result in problems such as the deterioration of the development efficiency. In this paper, we implement XMDMS to operate a distributed processing environment and then solve the problem of the reduction in the development efficiency caused by a load at the server. The experimental results shows that XMDMS improves the processing delay and network performance compared to MDMS.