• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.604-613
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• 2018

In this study, we analyzed the variations in the received signal strength index (RSSI) measured from Bluetooth beacons based on the strength and propagation direction of Bluetooth low energy (BLE) signal. Using a smartphone, we performed field experiments to investigate RSSI variations in the BLE signal transmitted by non-directional and directional beacons in an amethyst mine. In case of non-directional beacons, as the distance between the Bluetooth beacon and smartphone decreased, the RSSI increases, whereas as the BLE signal strength increased, the RSSI average gradually increased. The mean value of RSSI measured from the directional beacons was changed without relation to the facing angle between the Bluetooth beacon and smartphone. The results of this study can be used as basic data for developing a Bluetooth beacon-based proximity warning system for underground mines.

• Korea Real Estate Review
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• v.28 no.4
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• pp.37-51
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• 2018

The purpose of this paper is to analyze the effects of location factors on sales by restaurant type in the six districts of Seoul (Jongno-gu, Jung-gu, Yeongdeungpo-gu, Gangnam-gu, Seocho-gu, and Songpa-gu). Ordinary least squares (OLS) regression model is selected for four restaurant types whose spatial autocorrelation is not identified, spatial lag model (SLM) is only selected for seafood restaurant, and spatial error model (SEM) is selected for nine other restaurant types. The floating population and the workers of surrounding businesses have generally positive effects on the sales of restaurants. The floating population elasticity of the sales of restaurants are found to be in the descending order of Oriental food, pub, Western food, and traditional food restaurant, and the elasticity of the workers of surrounding businesses are in the descending order of bakery, Oriental food, and Western food restaurant. The spatial multiplier effects are in the descending order of Oriental food, pub, and Western food restaurant. There is a statistically significant sales gap between roast meat, pub, and bakery in Gangnam-gu and those in five other districts. The results of this research can help in starting a restaurant in that they can provide information on the suitability of location by restaurant type.

• The Safety technology
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• no.198
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• pp.16-17
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• 2014

지난해 산업재해율은 2012년과 동일한 0.59%를 기록했다. 2006년(0.77%) 이후 6년 연속 감소하던 재해율이 주춤하긴 했으나 2012년 사상 처음으로 0.6%대를 돌파한 이후 그 성과를 유지했다는 점에서 긍정적인 평가를 내릴 만하다. 지난해 연초부터 화학물질 누출, 붕괴 사고 등 대형재해가 빈발하면서 재해율이 크게 상승할 것이라는 우려가 있었지만 노 사 민 정 모두가 강한 재해예방 의지를 갖고 안전활동을 전개하면서 0.5%대를 유지하게 된 것이다. 하지만 내면을 들여다보면 여전히 문제점들이 발견된다. 특히 업종별로 건설업 재해가 지속적인 증가추세에 있고, 55세 이상 연령층의 재해자수가 늘어나는 등 안전관리체계의 부실점이 나타난 것이다. 이에 본지는 김규석 고용노동부 산업안전과 과장을 만나 문제점을 개선하기 위해 정부가 추진 중인 방안을 들어봤다.

• Journal of the Korean Geotechnical Society
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• v.17 no.5
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• pp.17-27
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• 2001

지하 굴착공동의 천장면에 형성되는 잠재적 키블록의 존재성과 운동학적 거동 양상 및 안정성을 해석적으로 분석할 수 있는 시스템을 개발하였다. 천장에서 측정된 절리들의 상대적인 위치와 방향성 자료를 이용하여 데이타베이스를 구축하였으며, 굴착설계도와 연계된 전산절리도를 작성하였다. 잠재적 키블록의 존재성과 거동양상은 사면체로 가정된 블록 옆면의 3차원 공간에서의 평면식을 절리의 방향성에 의거하여 구성하며 대수학적으로 분석되었다. 블록의 안정성 분석은 자중에 의해 미끄러짐이 발생되는 블록면의 공간 기하학적 특성을 고려하여 수행하였다. 개발된 분석시스템의 현장활용성을 검증하기 위하여 언양 자수정동굴에서 키블록 형성 및 거동양상을 조사하여 분석결과와 비교하였다.

• Journal of Embryo Transfer
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• v.11 no.1
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• pp.81-83
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• 1996

This study was carried out to investigate the effect of sperm concentration of 5ml maxi-straw on farrowing rate and number of pigs born alive per litter in deep frozen boar semen. We did not find out the effect of sperm concentration on post-thaw sperm motility and NAR acrosome. However, farrowing rate and number of pigs born alive per litter of 7. 5 x 10˚ /5ml and 10.0 x 10˚ /5m1 sperm concentrations were higher than those of 5. 0 /10˚ /5ml sperm concentration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.311-314
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• 2001

본 논문에서는 다중 경로 레일리 페이딩 채널에서 MC (Multi-Carrier) CDMA 시스템의 BER 성능을 분석하였고, 최근에 가장 강력한 부호화 기법으로 급부상하고 있는 터보 코드를 MC CDMA 시스템에 적용하여 성능 개선 정도를 평가하였다. 성능 해석 결과, 레일리 페이딩 채널에서는 강력한 성능 개선 기법을 적용하지 않는 한 사용자수와 E$_{b}$/N$_{o}$ 값에 관계없이 음성 서비스를 지원하지 못함을 알 수 있었다. 한편, 터보 코드를 성능 개선 기법으로 적용하면 BER 성능이 매우 개선되고, 사용자 수와 E$_{b}$/N$_{o}$ 값에 관계없이 음성 서비스를 충분히 지원할 수 있음을 알 수 있었다. 예를 들어 E$_{b}$/N$_{o}$ 가 10 dB이고 사용자 수가 10명인 경우, 터보 코드를 적용함에 의해 BER 성능이 약 5$\times$$10^{-3}$ 정도 개선됨을 알 수 있었다.

• Proceedings of the CALSEC Conference
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• 1999.11a
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• pp.499-508
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• 1999

최근 인터넷 이용자의 폭발적인 증가로 전자상거래 시장 규모는 급격히 증가하고 있으며, WEFA에 의하면 우리나라 전자상거래 시장규모는 1998년 약 3.6억불로 추정하고 있으며, 1999년도에는 전년 대비 6배 성장한 21.6억불로 세계 10위 규모를 기록할 것으로 예측되고 있다 국내 인터넷 이용자수는 96년 말부터 매년 약 2배씩 증가해왔으며, 1999년 말에는 700만명, 2000년말에는 최고 1400만명까지 확대될 것으로 예측되고 있다. 이러한 인터넷의 이용자의 확산은 금세기 들어 가장 빠른 속도로 보급된 매체인 TV보다 무려 4배 빠른 속도로 보급되고 있는 셈이다. 요컨대, 전세계가 인터넷 기반하의 전자상거래체제로 비즈니스 환경이 급격히 전환하고 있으며 그 중에서도 한국이 인터넷 이용자 숫자면 에서나 전자상거래 규모면 에서나 유별나게 성장성이 돋보이는 것이다. (중략)

• Journal of the Korean Regional Science Association
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• v.33 no.3
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• pp.21-30
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• 2017

The purpose of this study is to analyze the effect of urban characteristics on regional population and to suggest policy implications based on the analysis results. For this purpose, this study used spatial econometrics analysis(SAR, SEM, SAC) using data on 122 eup-myon-dong areas in Incheon Metropolitan City. As a result of the analysis, First, in terms of spatial, population density showed positive (+) effect while employment density has negative (-) effect. Also, the increase in the number of tertiary industries and workers in the industry has a positive (+) effect. Second, in terms of housing, the apartment ratio showed positive (+) effect and the increase of low-rise deteriorated housing has negative (-) effect. Third, the increase in educational facilities and urban parks showed positive (+) effect on population. In conclusion several policy implications for urban management found through this analysis are discussed.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.3
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• pp.159-166
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• 2007

Objective: To investigate whether semen parameters in infertile couples who undergone intrauterine insemination (IUI) change in the subsequent IUI cycle and the subsequent in vitro fertilization (IVF) cycle. Methods: Fifty-three infertile couples who had failed to become pregnant after the first IUI cycle with computer-assisted semen analysis (CASA) were included. After the first IUI, thirty-eight couples underwent the second IUI (Group 1), and fifteen underwent IVF-ET procedure (Group 2). All semen parameters including semen volume, concentration, motility and total motile sperm count were analyzed in the second IUI or IVF-ET procedure for comparison with the result of first IUI. Results: There were no significant differences in husband age, interval between the first and second procedure and cause of infertility. In Group 1, only sperm motility at the time of the latter IUI was significantly decreased when compared to the former IUI irrespective of the first semen parameters. In Group 2, sperm concentration, motility and total motile sperm count at the time of subsequent IVF were lower than the former IUI. By sub-analyses of Group 2, in the group of optimal semen parameter at IUI cycle, sperm concentration and total motile sperm count at the time of subsequent IVF were lower than the former IUI, while in the group of suboptimal semen parameter at IUI cycle, only sperm motility at the time of subsequent IVF were lower than the former IUI. Conclusion: The semen parameters in couples converted to IVF cycle were more adversely affected than those remained in IUI cycle. Further study on psychological stress should be necessary to explain the reason.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.30-41
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• 2015

This study was prepared by varying the type of barley sikhye to promote the use of barley. to learn the quality characteristics of traditional beverage sikhye, sikhyes were made out of different kinds of barley such as amethyst barley, black naked barley, tetrastichum barley, tetrastichum waxy barley, naked barley and naked waxy barley. The result of the study is as following. Regarding the length/width ratio of barley grain, black naked barley was the biggest; while amethyst barley was the smallest. Moisture content of barley grain was in the range of 54.96~71.74%. The saccharification liquid pH was in the range of 5.40~5.63 and the soluble solid content was in the range of 15.37~18.73 brix %. The saccharification liquid of sikhye made of tetrastichum waxy barley had the highest soluble solid content; while the saccharification liquid of sikhye made of black naked barley had the lowest soluble solid content. Reducing sugar was in the range of 4.35~7.42 mg/ 100 g; at which tetrastichum waxy barley sikhye had the highest reducing sugar while black naked barley sikhye had the lowest reducing sugar. The result of reducing sugar was similar to the result of soluble solid content. Black naked barley had low Lightness, redness and yellowness in its cooked rice grain and saccharification liquid. The result of barley sikhye characteristics was as following. Black naked barley had the strongest fullness while tetrastichum waxy barley had the weakest fullness. Black naked barley had strong feeling after swallowing the barley rice grain; while tetrastichum waxy barley had weak feeling after swallowing the barley rice grain. The result of feeling after swallowing the barley rice grain had correlation with fullness. The result of preference test was as following. naked waxy barley sikhye and naked barley sikhye had best outlook. In the smell, amethyst barley sikhye was the best. regarding texture, naked barley sikhye and naked waxy barley sikhye had high preference. In overall preference, naked barley sikhye was the best. Like above, there were differences in quality in sikhyes dependent on the variety of barley. In particular, tetrastichum waxy barley and naked barley will be able to increase the amount of sweetness without malt production during sikhye.