• ETRI Journal
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• v.29 no.4
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• pp.421-429
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• 2007

This paper presents a direct-conversion CMOS transceiver for fully digital DS-UWB systems. The transceiver includes all of the radio building blocks, such as a T/R switch, a low noise amplifier, an I/Q demodulator, a low pass filter, a variable gain amplifier as a receiver, the same receiver blocks as a transmitter including a phase-locked loop (PLL), and a voltage controlled oscillator (VCO). A single-ended-to-differential converter is implemented in the down-conversion mixer and a differential-to-single-ended converter is implemented in the driver amplifier stage. The chip is fabricated on a 9.0 $mm^2$ die using standard 0.18 ${\mu}m$ CMOS technology and a 64-pin MicroLead Frame package. Experimental results show the total current consumption is 143 mA including the PLL and VCO. The chip has a 3.5 dB receiver gain flatness at the 660 MHz bandwidth. These results indicate that the architecture and circuits are adaptable to the implementation of a wideband, low-power, and high-speed wireless personal area network.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.10
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• pp.86-93
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• 2004

This paper presents the remote measurement of the ECU signals adopted with KWP 2000 protocol using the wireless communication technique of bluetooth. The bluetooth technology will be the most promising network paradigm which can open the new area in the information technology. Especially, bluetooth module is able to link all the electrical products and personal computers to cellular phone or PDA. This research has a try to design a wireless measurement model of ECU signal based on the car telemery system using bluetooth device. In order to measure the ECU signals, we designed the interface circuits which is able to communicate between the ECU system and the terminal circuits according to the ISO, SAE regulation of communication protocol standard. A microprocessor S3c341 OX is used for the system control and communication of ECU signals. The embedded system software is programmed to measure the ECU signals using the ARM compiler and ANCI C based on Micro/OS-II kernel to communicate between two bluetooth modules using bluetooth stack. The remote measurement of ECU signals using the bluetooth was designed and implemented to evaluate the performance of wireless network to the transmit measurement data. The possibility for the remote measurement of the self diagnosis signals of ECU adopted with KWP2000 protocol verified through the developed systems and algorithms in embedded system.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.747-753
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• 2020

This study aims to interpret the meaning of a successful entrepreneur from the perspective of women entrepreneurs in Malang, Indonesia. This research offers a phenomenological approach using purposive sampling. Data was collected by in-depth interviews using structured questionnaire with registered women entrepreneurs in Malang obtained from MSMEs (micro small and medium-sized enterprises) entrepreneurs. The 'continually developing' is one of the meanings of a successful entrepreneur. This study also found that success is when what women do can be useful to others. Besides, the meaning of success has two criteria, i.e., when they can meet their needs (individual satisfaction) and social performance as a goal to be achieved by entrepreneurs. The motivation of women entrepreneurs to establish their venture was not only financial returns, but also personal satisfaction, which was also the indicator of entrepreneurial success for women. This study has several limitations. First, our sample size is too small and consists of entrepreneurs that have an average age above 40 years. Hopefully, further research will be able to generalize our findings to a broader sample in various industries outside the city of Malang. As our research shows, the criteria and meaning of success may be different for a larger sample of entrepreneurs.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.5
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• pp.351-360
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• 2016

Rapid population growth with high living standards and high electronics use for personal comfort has raised the electricity demand exponentially. To fulfill this elevated demand, conventional energy sources are shifting towards low production cost and long term usable alternative energy sources. Hybrid renewable energy systems (HRES) are becoming popular as stand-alone power systems for providing electricity in remote areas due to advancement in renewable energy technologies and subsequent rise in prices of petroleum products. Wind and solar power are considered feasible replacement to fossil fuels as the prediction of the fuel shortage in the near future, forced all operators involved in energy production to explore this new and clean source of power. Presented paper proposes fuzzy logic based Energy Management System (EMS) for Wind Turbine (WT), Photo Voltaic (PV) and Diesel Generator (DG) hybrid micro-grid configuration. Battery backup system is introduced for worst environmental conditions or high load demands. Dump load along with dump load controller is implemented for over voltage and over speed protection. Fuzzy logic based supervisory control system performs the power flow control between different scenarios such as battery charging, battery backup, dump load activation and DG backup in most intellectual way.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.11
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• pp.1004-1011
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• 2016

In this paper, we suggested the methodology of analyzing and reconstructing of measured electromagnetic emanations from the Micro Controller Unit(MCU) chip of Universal Serial Bus(USB) keyboard. By analyzing electromagnetic emanations, entered information is found at keystroke and furthermore, information security problems such as personal information leakage and eavesdropping can be arisen. USB keyboards make the radiated signal according to the signal transmission mechanism. Electromagnetic emanations were measured by log periodic antenna and wideband receiver and were analyzed by signal processing algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.8
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• pp.1937-1942
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• 2010

In this paper, RFID technology was applied to fitness center and order to exercise the right of each user without the guidance of a personal trainer should be made systematically. for example, excercise sequence, equipment usage, excercise and golas etc. Also, Customers who use the fitness center using RFID is trainer at a low-cost under the guidance of the same effect can be expected. In this paper, Our system will record the movements of time, as well as our system can be analyze of excercise using micro processor and acceleration sensor.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.440-447
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• 2007

This paper is dealing with recent hot issues related with copper toxicity and its criteria, which was caused by a new government policy relocating some industries discharging priority-water quality pollutants from the watershed of Han River to other regions. Author is not interested in arguments between two sides of anti- and pro-policy but would like to go over status of copper pollution and its management and regulatory policy in Korea. From the data of published Research Journals and Reports, it can be concluded that copper is very common metal not only in the effluent from publically owned wastewater treatment plants, but also as a non-point source pollutant in the rainfall runoff. In addition, there have been very few studies personal interests, not by National Fund Basis. In order to enforce a new regulation, national-wide macro and micro-mass balance work of heavy metals should be performed in advance. In particular, background concentration and measurement errors have to be clearly defined before a new standard or criteria is established. The new standard has to be acceptable in terms of the best available technology and cost.

• Human Ecology Research
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• v.57 no.3
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• pp.353-367
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• 2019

This study investigates the influence of family-friendly workplace policies and organizational culture on the willingness of married female managers to have a child. The analysis includes 353 married female managers from the $6^{th}$ survey of the 2016 Korean Women Manager Panel. Factors that are found to influence the respondents include age, education, number of children, job position, promotional goals, accessibility to family leave, accessibility to shorter work hours during the child-rearing period, and organizational culture. Female managers who can easily use family leave or who have shorter work hours during the child-rearing period show a higher willingness to have a child. By contrast, those whose work places employ a fair and horizontal organizational culture are less willing to have a child. The introduction of family-friendly policies are not found to be statistically significant determinants of female managers' willingness to have a child. We find that influencing family-friendly policies between the first and second childbirth differ. The accessibility of family-friendly policies that affect the willingness of female managers to have a child when they have no child include parental leave, employer-supported childcare, and childcare subsidies. For improving their willingness to have a second child, accessibility to both family leave and shorter work hours during the child-rearing period are effective. In conclusion, the government should strongly consider micro-personal factors, such as family-friendly workplace practices and organizational culture, when executing policies to reverse the current trend of low fertility.

• Communications for Statistical Applications and Methods
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• v.28 no.5
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• pp.447-462
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• 2021

In insurance, the surrender rate is an important variable that threatens the sustainability of insurers and determines the profitability of the contract. Unlike other actuarial assumptions that determine the cash flow of an insurance contract, however, it is characterized by endogenous variables such as people's economic, social, and subjective decisions. Therefore, a microscopic approach is required to identify and analyze the factors that determine the lapse rate. Specifically, micro-level characteristics including the individual, demographic, microeconomic, and household characteristics of policyholders are necessary for the analysis. In this study, we select panel survey data of Korean Retirement Income Study (KReIS) with many diverse dimensions to determine which variables have a decisive effect on the lapse and apply the lasso regularized regression model to analyze it empirically. As the data contain many missing values, they are imputed using the random forest method. Among the household variables, we find that the non-existence of old dependents, the existence of young dependents, and employed family members increase the surrender rate. Among the individual variables, divorce, non-urban residential areas, apartment type of housing, non-ownership of homes, and bad relationship with siblings increase the lapse rate. Finally, among the financial variables, low income, low expenditure, the existence of children that incur child care expenditure, not expecting to bequest from spouse, not holding public health insurance, and expecting to benefit from a retirement pension increase the lapse rate. Some of these findings are consistent with those in the literature.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.6
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• pp.13-24
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• 2017

The purpose of this study is to examine the effect of the management of receivables on the management performance of micro manufacturing industries. The results of the survey are as follows. First, among the factors of management of pre- and post-trade receivables in the micro manufacturing industries, management organization and regulations, contract execution management, bad debt control, which are the subordinate factors of credit control, are positive (+) significant effect on stability. In terms of profitability, management organizations and regulations, which are subordinate factors of credit control management, have a positive (+) significant effect on profitability. The recovery management, which is a factor of management of post - receivable receivables, did not have a significant effect on the stability and profitability of financial management performance. Second, the effect of financial performance on organizational satisfaction is positively related to stability, while profitability has no significant effect on organizational satisfaction. The implication of this study is that pre - trade receivables management is more important than post - trade receivables management in the management of accounts receivables of micro manufacturing industries. Proactive credit management refers to the procedure of establishing and managing personal guarantees and physical guarantees in order to smooth the execution of the obligations at the same time as the contract is concluded through processes such as credit investigation, analysis and evaluation, and sales decision before the contract is concluded. Post receivables management based on the assumption of default is a receivables management procedure from receipt of receivables that are already defaulted to bad debts to bad debt processing. If the collection of receivables is delayed or bad debt is increased, Furthermore, a corporation may be subject to bankruptcy risk (insolvency by paper profits). Therefore, it is meaningful that this study suggests direction to induce change of contract type in advance by understanding the possibility of settlement of accounts receivable and recovery of bad debts within the day of transition in case of contract of micro manufacturing industries.