• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.6
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• pp.1031-1040
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• 2023

Propagation characteristics in line-of-sight(LOS) paths in 3, 6, 10, and 17 GHz frequency bands were measured and analyzed in two different indoor corridors: second floors of Buildings D2 and E2. The measurement was designed to measure when the receiving antenna moved at 0.5 m intervals from 3 m to 30 m, while the transmission antenna was fixed. The analysis of the two indoor corridors was compared by applying basic transmission loss, root mean square (RMS) delay spread, and K-factor. For basic transmission loss, the loss coefficient of the floating intercept path loss model was higher in the indoor corridor of Building E2 than in that of Building D2. Similarly, the RMS delay spread in the time domain was greater in the indoor corridor of Building E2. However, the indoor corridor of Building D2 exhibited higher K-factor in the 3, 6, and 17 GHz bands with lower wave propagation in the 10 GHz band. Despite the 2 indoor corridors being identical, the propagation characteristics varied due to different internal structures and materials. The results provide measurement data for ITU-R Recommendations regarding various indoor environments.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.4
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• pp.500-506
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• 2007

Purpose: This study was conducted to analyze the health concerns, health behavior, and related factors for elders taking part in activities at senior centers. Method: A total of 811 elders were selected through conveniently sampling. Data were collected from November 21, 2006 to December 20, 2006. Data analysis included frequency, t-test, ANOVA, Duncan test, and Stepwise Multiple Regression using SPSS Win 15.0. Results: For health concerns statistically significant differences were found for gender, age, family, pockety money, sleeping time, regular health check-ups, and exercise. For health behavior statistically significant differences were found for gender, age, family, pocket money, religion, medical insurance, perceived health status, sleeping time, regular health check-ups, chronic illness, regular breakfast, exercise, and drinking. Perceived health status was identified as a variable influencing the health behavior. Conclusion: The results suggest that perceived health status can be considered as factor for significant nursing interventions to help single elders and older elders in senior centers.

• Journal of IKEEE
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• v.23 no.3
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• pp.878-882
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• 2019

XOR(exclusive-OR)-XNOR(exclusive NOR) circuit is a basic component of 4-2 compressor for high performance arithmetic operation. In this paper we propose an energy efficient XOR-XNOR circuit. The proposed circuit is reduced the internal parasitic capacitance in critical path and implemented with 8 transistors. The circuit produces a perfect output signals for all input combinations. Compared with the previous circuits, the proposed circuit has a 14.5% reduction in propagation delay time and a 1.7% increase in power consumption. Therefore, the proposed XOR-XNOR is reduced power-delay- product (PDP) by 13.1% and energy-delay-product (EDP) by 26.0%. The proposed circuits are implemented with standard CMOS 0.18um technology and verified through SPICE simulation with 1.8V supply voltage.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.459-470
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• 2007

The structural equation modeling techniques were used to assess a model of chemistry learning strategy based on self-handicapping tendency and goal orientation. Data were collected during chemistry lessons in two high schools. In the optimal model II-2 of this research, the self-handicapping tendency was negatively related to the use of self-efficacy. The learning goal was positively related to the use of self-efficacy and to learning strategy. The performance- approach goal was positively related to self-efficacy but presented an negative relationship to learning strategy. The performance-avoidance goal was negatively related to self-efficacy but presented an positive relationship to learning strategy. Besides affecting the learning strategy through self-efficacy indirectly, the learning goal, performance-approach goal, and performance-avoidance goal affected learning strategy directly. The self-handicapping tendency and performance- avoidance goal were a negative predictors of self-efficacy, but the learning goal and performance-approach goal were a positive predictors. And the self-efficacy affected learning strategy positively. The implications of these findings for learning strategy in chemistry are discussed. Although the paths model of relationships of the motivations to learn and learning strategies in chemistry education as mentioned above is established, the more systematic search for the higher self-efficacy and learning strategy in different courses and curriculums may be needed.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2001.11a
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• pp.96-100
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• 2001

본 논문에서는 skeleton slot 복사기를 이용하여 GSM 900과 GSM 1800에서 사용할 수 있는 이중대역 안테나를 설계 및 제작하여 측정 결과를 비교 분서하였다. 기본적인 skeleton slot 구조에서는 낮은 밴드의 2배 이상의 주파수에서는 수평 빔폭이 일정치 않고, 정재파비 특성이 불량하였으나, 급전부와 측면 방사부분의 다중경로 형성 및 절곡 구조를 이용하여 이를 해결하였다. 안테나의 크기는 반사판이 190$\times$190(mm), 복사기는 154$\times$106(mm), 높이는 33mm로 하여 현재 서비스 사업자틀이 주로 사용하는 크기로 구성하였다. 구성 재질은 1mm 두께의 알류미늄판을 이용하며, 이를 NCT로 타공 및 절곡하여 제작하였기 때문에 대량 생산 시 단가를 낮출수 있다. 실측결과 900MHz 대역에서 13.7%, 1800MHz 대역에서 16.4%의 -l0dB 반사손실 대역폭을 만족하고, 방사패턴도 대역별로 $\pm$1$^{\circ}$이내의 일정한 양상을 보여 이중대역 안테나로서의 요구를 만족하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.327-332
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• 2021

At the package level, semiconductor reliability inspections involves mounting a semiconductor chip package on a test socket. The form of the test socket is basically determined by the form of the chip package. It also acts as a medium to connect with test equipment through mechanical contact of the leads and socket leads in the chip package, and it minimizes signal loss in a signal transmission process so that an inspection signal can be delivered well to the semiconductor. In this study, a technique was applied to examine the interdependence of adjacent electrical transfer routes and the structure of adjacent electrical transfer paths. The goal was to enable short-circuit testing of fewer than 100 silicon test sockets through a single interface for life tests and precision measurements. The test results of the developed device show a test precision of 99% or more and a simultaneous test speed characteristic of 0.66 sec or less.

• The Journal of Korean Society for School & Community Health Education
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• v.9 no.2
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• pp.105-118
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• 2008

Objectives: This study was performed in order to figure out oral health knowledge level of home room teachers of elementary schools in Daegu area. This study was conducted from March through May 2008. Methodology: A total of three hundred and ten (43 male teachers and 267 female teachers) home room teachers of elementary schools were surveyed. The collected data were analyzed by X2 test and one way ANOVA test by using SPSS 11.0 program. Results: Most oral health knowledge was obtained from dental clinics (45.8%) and mass media and books (40.0%). Many respondents reported that the main purpose of oral hygiene was prevention of periodontal diseases. The highest number of respondents reported that fluoridated tooth paste was the best for fluoride effects on teeth. 56.7% of the respondents said that they visited periodically dental clinics for dental caries prevention. The respondents did not have much knowledge about the importance of fluoride in dental caries. Many respondents did not know that the plaque is the main cause of periodontal diseases. Conclusion: Effective oral health education program should be prepared for the elementary school teachers because their knowledge levels of oral health is not sufficient for students.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.481-485
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• 2005

The port entry system of the inner harbor in Pyeongtaek${\cdot}$Dangjin was planned as lock-gate in 'Master plan project on port planning in Asan industry base(1990)‘, but was changed to tidal harbor in 'Project maintaining Master plan for comprehensive development of Pyeongtaek${\cdot}$Dangjin port(2001)'. Accordingly, southern sea bank constructed under the lower part of Seohae-bridge will be removed so that inbound/outbound vessels for the inner harbor can navigate at all times. However, in the view of the safety on passing through the lower of Seohae-bridge, navigating conditions for the inner harbor will be restricted in the single-way of 50,000 DWT vessel and the two-way of vessel less than 30,000 DWT Therefore, this study carried out the estimation of traffic congestion arising from these vessels with above restrictions q[ter supposing annual inbound/outbound vessel's numbers for loading and unloading cargo surveyed on the inner harbor.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.1
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• pp.105-113
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• 2002

In this study, the steady state performance analysis program was developed for a turboprop engine, and its performance was analyzed at uninstalled and installed conditions. For the purpose of evaluation the developed program was compared with the performance data provided by the engine manufacturer and analysis results of GASTURB8.0 program. It was confirmed that the developed program was reliable because the results by the developed program were well agreed with those by GASTURB8.0 within %%. The linear and non-linear GPA(Gas Path Analysis) programs for performance diagnotics were developed, and selection of optimal measurement variables was studied. Furthermore, in order to investigate effects of the number and the kind of measurement variables, the linear and non-linear GPAs were analyzed with various measurement set. If the measurement parameters were properly selected, the reliable and economic faults detection might be possible even thought the small number of measuring parameters were used.

• Journal of the Korea Society of Computer and Information
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• v.26 no.1
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• pp.189-199
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• 2021

This study examines the relationship between internal marketing, market orientation, patient satisfaction, and hospital image, and especially focuses on the effect of CEO's role on internal marketing at a local national university hospital. A survey was conducted using the convenient sampling technique and 222 questionnaires excluding unreliable replies were used in the final analysis for the hypothesis testing. SPSS 21.0 was used for the basic analysis of the collected data, and confirmatory factor analysis was performed for reliability and validity using AMOS 21.0. Path analysis was performed for the hypothesis testing. The results of this study are as follows: First, the role of CEO positively affects internal marketing. Second, internal marketing has a positive effect on market orientation, and leadership is the most influential factor of internal marketing. Third, market orientation has a positive effect on patient satisfaction and hospital image, which are non-financial organizational performance. Therefore, internal marketing plays a major role in improving market orientation, patient satisfaction, and hospital image, and it is identified that the activation of internal marketing depends on the support of CEO in hospitals.