• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.5
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• pp.7-15
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• 2007

In wireless communication networks, single-radio single-channel architecture degrades throughput and end-to-end delay due to half-duplex transmission of wireless node and route intra interference. Also, In contention-based MAC (Medium Access Control) architecture, channel contention reduces throughput and packet collision enlarges end-to-end delay. In this paper, we use multi-radio multi-channel architecture which will make wireless node to operate in full duplex mode, and exclude route intra interference. Based on this architecture, we propose a new link metric, ccf which reflects the characteristics of a contention-based wireless link, and propose a routing path metric MCCR considering channel switching delay and route intra interference. MCCR is compared with MCR by simulation, the performance of a route established by MCCR outperforms the performance of a route by MCR in terms of throughput and end-to-end delay.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.101-106
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• 2014

This paper presents a wide dynamic range radio-frequency (RF) root-mean-square (RMS) power detector using an automatic gain control (AGC) loop. The AGC loop consists of a variable gain amplifier (VGA), RMS conversion block and gain control block. The VGA exploits dB-linear gain characteristic of the cascade VGA. The proposed circuit utilizes full-wave squaring and generates a DC voltage proportional to the RMS of an input RF signal. The proposed RMS power detector operates from 500MHz to 5GHz. The detecting input signal range is from 0 dBm to -70 dBm or more with a conversion gain of -4.53 mV/dBm. The proposed RMS power detector is designed in a 65-nm 1.2-V CMOS process, and dissipates a power of 5 mW. The total active area is $0.0097mm^2$.

• Management & Information Systems Review
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• v.30 no.4
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• pp.441-474
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• 2011

This purpose of this study is to examine the relationships of ethical leader and ethics management system with employees's organizational citizenship behavior and the mechanism underlying these relationships. A questionnaire survey was conducted involving 1,035 full-time employees from large and medium industries in Daegu and Gyeong-buk provinces. Regression analysis was used to test the hypotheses. The results showed that both of ethical leader and ethics management system were positively related with employees's organizational citizenship behavior. As expected, these relationships were mediated by organization-oriented ethical climate and social responsibility-oriented ethical climate respectively. The findings of this study are as followings: First, employees tend to show their pro-social behavior when they perceive their leaders act ethically and ethics management is well institutionalized. Second, building up the organization-oriented ethical climate and social responsibility-oriented ethical climate can be a powerful strategy to enhance employees's organizational citizenship behavior.

• Smart Structures and Systems
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• v.17 no.1
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• pp.91-105
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• 2016

One of the most commonly used techniques to strengthen steel reinforced concrete structures is the application of externally bonded patches in the form of carbon fiber reinforced polymers (CFRP) or recently, textile reinforced cements (TRC). These external patches undertake the tensile stress of bending constraining concrete cracking. Development of full-field inspection methodologies for fracture monitoring are important since the reinforcing layers are not transparent, hindering visual observation of the material condition underneath. In the present study acoustic emission (AE) and digital image correlation (DIC) are applied during four-point bending tests of large beams to follow the damage accumulation. AE helps to determine the onset of fracture as well as the different damage mechanisms through the registered shifts in AE rate, location of active sources and change in waveform parameters. The effect of wave propagation distance, which in large components and in-situ can well mask the original information as emitted by the fracture incidents is also discussed. Simultaneously, crucial information is supplied by DIC concerning the moments of stress release of the patches due to debonding, benchmarking the trends monitored by AE. From the point of view of mechanics, conclusions on the reinforcing contribution of the different repair methodologies are also drawn.

• Journal of the Korea Society of Computer and Information
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• v.20 no.11
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• pp.175-181
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• 2015

In this paper, based on the reference, we try to review the second issues about opening medical market and health care privatization by each topic and propose the measures and alternatives. Currently, in Korea, connection with launch of the WTO system and force of the FTA, the medical industries getting liberalization and globalization. Thus, it is expected to plunge to full-free competition system, and Korean medical institutions started the global competition which completely different dimension. It means that according to the liberalization of the healthcare market the real problem can be caused and also, the incessant discussion and effort for the implementation of international community are needed. Regard to attracting foreign patients and opening medical markets, the government also spreading the continued advancement strategy politically until now. However, generating problems with implication is inevitable and measures and alternatives to it are also needed. In accordance with the opening, the accompanying suggestions is medical privatization, that is, whether the health care pursue the profit not the not-for-profit and the current hospitals in Korea they are leaved as non-profit hospitals and let the make the subsidiary as general commercial enterprises, it seems indirect. However, it is like a healthcare privatization virtually thus, implication seem be large. Of course, through the public opinion and legal reservation, the liberalization and privatization of medical market can be delayed or not forced. It would be not fit in the flow of the inevitable globalization, it can be inhibited national interest and economic development also, and it can be the critical implications which shake the health system and collapse of the domestic health care market.

• Journal of Korean Home Economics Education Association
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• v.8 no.1
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• pp.79-91
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• 1996

The purpose of the study is to see as to how much of changes has occurred in the newly revised Home Economics Textbooks required by the 6th Curriculum as compared to those by the former 5th Curriculum, and to seek future policy directions with can be improved even better, if any, for further revision. To implement this proposal, the study employs 8 different textbooks published in 1995 geared for the 6th Curriculum for data base. The components of the contents divides into two major parts. The first part falls into a category of holistic analysis of the textbooks, which gives a general perspective of the changes in the textbook revised. It includes those areas of changes in the total number of pages, cover page, illustrations, table of contents, appendices, unit cover, introductory remarks, summary and evaluation, etc. It also covers the information on authors of textbook. The latter part consists of several specific areas of major changes occurred in the textbooks for the 6th Curriculum. It covers such areas of changes in the composition of category and its weight, laboratory experiences, and illustrations and tables. To conclude the study, among many findings, two major points are of great importance to mention here. First, the new textbooks have adopted more of varieties in physical appearances and contents per se as to the older ones. And yet, there still found a weakness in numbers of authors participated to a full reflection on contents variety. In addition, the background of authors reflected on an unrealistic idealism which lacks the on-site information provided by the school teachers. Second, the strict regulations created by the Ministry of Education for developing textbook found restricting the authors creativity and thus contents variety of textbooks. Those restricting factors include letter type and size, coloring, paper quality, and volume size.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.2A
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• pp.129-136
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• 2005

A multiplier generator, VPM_Gen (Variable-Precision Multiplier Generator), which generates Verilog-HDL models of multiplier cores with user-defined bit-width specification, is described. The bit-widths of operands are parameterized in the range of $8-bit{\sim}32-bit$ with 1-bit step, and the product from multiplier core can be truncated in the range of $8-bit{\sim}64-bit$ with 2-bit step, resulting that the VPM_Gen can generate 3,455 multiplier cores. In the case of truncating multiplier output, by eliminating the circuits corresponding to the truncation part, the gate counts and power dissipation can be reduced by about 40% and 30%, respectively, compared with full-precision multiplier. As a result, an area-efficient and low-power multiplier core can be obtained. To minimize truncation error, an adaptive error-compensation method considering the number of truncation bits is employed. The multiplier cores generated by VPM_Gen have been verified using Xilinx FFGA board and logic analyzer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8A
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• pp.620-625
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• 2003

The coplanar waveguide bandpass filter using folded-line stepped-impedance resonators(SIRs) is proposed. The folded-line SIR has about λ/8 length using the short-circuited end on coplanar waveguide. It make that the bandpass filter has the half size in comparison with general λ/4 SIR filter. In this paper, we derive the equivalent circuit and design the bandpass filter by using that. We design and fabricate the bandpass filter which has 5 GHz center frequency and 3 % fractional bandwidth. The measurement results fur 4-pole folded SIR bandpass filter agreed well with full-wave simulation and equivalent circuit results. The fabricated bandpass filter has a good spurious characteristic, which the harmonic frequency appeared at 2.5f$\_$0/). The proposed folded-line SIR bandpass filter are applicable for MMIC and High-Tc superconducting filters. bandwidth.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.376-383
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• 2012

In this paper, we provide a general expression of spatial multiplexing gain (SMG) for two mutually interfering multiple-input multiple-output (MIMO) broadcast channels, referred to as MIMO-IBC, when some of user messages are made available to base stations through a common noiseless backbone line. The MIMO-IBC has two base stations and multiple users, each equipped with multiple antennas, where independent messages are transmitted over fixed channels. From the derived results, we observe the variation of the SMG with respect to the presence of a coordination as well as various antenna distributions, and compare the derived result to the SMG of the case with full cooperation among users.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10A
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• pp.776-783
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• 2009

Current-cut circuit is an effective method to obtain low power consumption in wireless communication systems as high speed OFDM. For the operation of current-mode FFT LSI with analog signal processing essentially requires current-mode serial-to-parallel/parallel-to-serial converter with multi input and output structure. However, the Hold-mode operation of current-mode serial-to-parallel/parallel-to-serial converter has unnecessary power consumption. We propose a novel current-mode serial-to-parallel/parallel-to-serial converter with current-cut circuit and full chip simulation results agree with experimental data of low power consumption. The proposed current-mode serial-to-parallel/parallel-to-serial converter promise the wide application of the current-mode analog signal processing in the field of low power wireless communication LSI.