• 사물인터넷융복합논문지
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• 제7권2호
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• pp.47-53
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• 2021

IoT(Internet of Things) 환경에서 한정된 대역폭을 갖는 서버에서 저장된 비디오 데이터를 많은 클라이언트들에게 전송하기 위해서는 전송률 변화 횟수, 첨두 전송률, 전송률 변화량 등의 요소를 고려하여 전송 계획을 세워야 한다. 이 전송 계획을 스무딩이라고 하며 전송률 증가 횟수를 최소화하는 CBA, 전송률 변화횟수를 최소화하는 MCBA, 전송률 변화량을 최소화하기 위한 MVBA 등이 있다. 본 연구에서는 평균 전송률을 최소화하기 위해 제안된 알고리즘[16]에 대한 성능을 평가하기 위해, 제안된 알고리즘과 기존 스무딩 알고리즘들에서의 첨두 전송률, 전송률 변화횟수, 전송률 증가횟수, 전송률 변화량, 첨두 전송률 이용률, 평균 전송률을 다양한 비디오 데이터와 버퍼 크기로 비교한다. 평가 결과 제안 알고리즘은 평균 전송률이 가장 낮은 전송 계획을 세움으로써, 서버의 한정된 네트워크 자원의 효율적인 사용에 도움을 준다.

• 한국조경학회지
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• 제41권6호
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• pp.140-146
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• 2013

본 연구는 휴대용 광합성측정장치(CIRAS-2, PPS, UK)를 이용하고, 토양 수분조건에 따른 섬기린초의 생리특성을 파악하였다. 섬기린초의 광합성 속도, 식물수분이용효율, 호흡속도 등 측정을 통하여 섬기린초의 생장에 가장 적합한 광도와 토양 수분범위를 명확하게 파악하였다. 광도에 따른 광합성 속도가 증가하였고, $600{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ 경우에서 최고점에 도달한 후 그 이후 감소하는 경향을 나타났다. 토양 수분 조건에 따른 섬기린초의 광합성 속도과 식물수분이용효율은 수분함량 11.31%에서 가장 높은 값을 보였으며, 호흡속도는 수분함량 7.91%에서 가장 높은 값을 나타냈다. 그 결과에 의하면, 섬기린초는 가장 적합한 광도 범위가 $600{\sim}1,200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$이고, 수분 범위가 7.09~11.31%이다.

• 한국의료질향상학회지
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• 제18권1호
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• pp.71-78
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• 2012

Background : The objective of this study was to examine the effect of management system for the appropriate prophylactic use of antibiotics in surgical patients at a tertiary hospital from 2007 to 2010. Methods : We collected clinical data of three different surgical procedures(colectomy, heart surgery, hysterectomy) for three months of 2007 and 2010, respectively. The number of total cases was 245(137, 54, 54) in 2007, 240(133, 42, 65) in 2010. We measured the rate of use of inappropriate prophylactic antibiotics, administration within 1 hour prior to the incision and the antibiotics prescription days after surgery. To evaluate the effectiveness of the management system, the results of the two groups(Group1=2007, Group2=2010) were compared by t-test, chi-square test or Fisher's exact test. Result : The rate of Aminoglycoside uses decreased drastically from 11.4% to 0.8%(P<.001). The selection of 3rd/4th Cephalosporin dropped from 11.8% to 5.8%(P=.020). The combination of antibiotics decreased from 27.8% to 11.7%(P<.001). The antibiotic prescription rate on discharge declined from 11.8% to 2.5%(P<.001) and the number of antibiotics prescription days after surgery was shortened from 4.2 days to 2.3 days(P<.001). No significant difference in the rate of administration within 1 hour between two groups was found. Through 3-year management, 5 out of 6 measures were significantly improved(except the administration within 1 hour). The rate of surgical site infection decreased from 2.4% to 1.3%(P=.504). Conclusion : The findings demonstrate that the management system for the prophylactic use of antibiotics in surgical patients was effective in decreasing the rate of surgical site infection during 3 years.

• Safety and Health at Work
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• 제7권1호
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• pp.32-37
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• 2016

Background: Previous research has shown that paramedics are exposed to risks in the form of injuries to the musculoskeletal system. In addition, there are studies showing that they are also at increased risk of cardiovascular disease, cancer, and psychiatric diseases, which can partly be explained by their constant exposure to stress. The aim of this study is to evaluate whether the use of shoulder straps decreases physical effort in the form of decreased heart rate and cortisol concentration. Methods: A stretcher with a dummy was carried by 20 participants for 400 m on two occasions, one with and one without the shoulder straps. Heart rate was monitored continuously and cortisol samples were taken at intervals of 0 minutes, 15 minutes, 30 minutes, 45 minutes, and 60 minutes. Each participant was her or his own control. Results: A significant decrease in heart rate and cortisol concentration was seen when shoulder straps were used. The median values for men (with shoulder straps) at 0 minutes was 78 bpm/21.1 nmol/L (heart rate/cortisol concentration), at 15 minutes was 85 bpm/16.9 nmol/L, and at 60 minutes was 76 bpm/15.7 nmol/L; for men without shoulder straps, these values were 78 bpm/21.9 nmol/L, 93 bpm/21.9 nmol/L, and 73 bpm/20.5 nmol/L. For women, the values were 85 bpm/23.3 nmol/L, 92 bpm/20.8 nmol/L, and 70 bpm/18.4 nmol/L and 84 bpm/32.4 nmol/L, 100 bpm/32.5 nmol/L, and 75 bpm/25.2 nmol/L, respectively. Conclusion: The use of shoulder straps decreases measurable physical stress and should therefore be implemented when heavy equipment or a stretcher needs to be carried. An easy way to ensure that staff use these or similar lifting aids is to provide them with personalized, well-adapted shoulder straps. Another better option would be to routinely sewn these straps into the staff's personal alarm jackets so they are always in place and ready to be used.

• 문화기술의 융합
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• 제4권4호
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• pp.187-199
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• 2018

본 연구는 2012년 한국의료패널자료의 보건의식행태에 응답한 만 18세 이상만으로 처리하였으며 전체 2,757명, 남자 2,614명(44.6%), 여자 143명(2.3%)으로 선정하였다. 흡연으로 의료이용 및 의료비지출 자료를 통하여 흡연자의 응급. 입원, 외래 의료이용횟수에 따른 의료비를 통하여 사회적 비용을 추계하였다. 사회적비용은 보건경제학자인 Rice(1968)의 의해 정립된 사회적관점을 채택하여 의료이용에 따른 의료비와, 보험자(공단)비용, 본인부담금, 비급여, 생산성 비용을 합산하여 사회적비용을 산출하였다. 흡연상태별 연간 응급의료이용률은 인구 백명당 흡연자 7.5%, 이용횟수 9.8회 사회적비용은 809,003원으로 나타나고 있다. 흡연상태별 인구 백명당 연간 입원의료이용률은 인구 백명당 흡연자 9.6%, 이용횟수 9회, 사회적비용은 706,870원으로 나타나고 있다. 흡연상태별 연간 외래이용률은 흡연 68.6%, 연간의료이용건수는 9건, 사회적비용은 706,870원으로 나타났다.

• 보건교육건강증진학회지
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• 제31권5호
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• pp.147-158
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• 2014

Objectives: This study aims to examine the association of depression, suicidal behaviors with smartphone use behaviors among Korean adolescents. Methods: We analyzed data from 'Youth Health and Life Skills Survey' in 2013. The survey was based on self-reported questionnaires distributed to 915 grade 7th and 8th students at four middle schools in Gangdong-gu, Seoul, Korea in 2013 to evaluate the effects of 'Youth Health and Life Skills' program. Depression and suicidal behaviors were measured in terms of the experience rate, and smartphone use behaviors were measured with average hours of smartphone use a day and overindulged behaviors in smartphone use by using 5-point Likert scales. We examined the association of depression and suicidal behaviors with smartphone use behaviors by using t-test and regression analyses. Results: 21.5% of respondents have ever felt depressed or hopeless to lose interest in school life almost everyday for 2 weeks or longer in the past year. The experience rate of suicidal ideation, suicide plan, and suicidal attempt were 21.1%, 6.1%, and 5.7%, respectively. The mean of average hours of smartphone use a day was 3.9 hours, and the mean score of overindulged behaviors in smartphone use was 2.99. The students who have experienced depression and suicidal behaviors were more likely to have more smartphone using time and higher scores of overindulged behaviors in smartphne use than those who have not. Conclusion: We concluded that for preventing addictive or problematic smartphone use behaviors among adolescents we should consider and develop more positive strategies for the moderate use of smartphone than regulatory measures, which include the implementation of skill-based health education program including life skills at schools and the development of smartphone applications useful for resolving mental stress and promoting mental health.

• 대한전자공학회논문지
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• 제19권6호
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• pp.84-90
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• 1982

본 논물에서는 HCDM(hybrid companding delta modulation)을 사용하여 음성을 부호화할 때, 음성의 간헐성을 이용하여 전송속도를 줄이거나 잡음에 대한 신호비(SQNR)을 증가시키는 연구를 하였다. 음성부분과 묵음(silence)부분을 식별하는 판별기를 이용하여 음성의 묵음부분을 검출하며, 이때 음성부분에 대해서는 HCDM 부호화를 행한다. 음성을 5msec 간격으로 검사하여, 그때 검출되는 묵음부분에 대해서는 그 구간이 묵음이라는 정도만을 전송하며, 수신단에서는 이 정보를 이용하여 묵음부불을 재생한다. 그런데 HCDM 부호기는 2진 신호를 일정한 속도로 또 동기적으로 전송하기 때문에, 버퍼 (buffer)를 사용해야 하며 또한 그것을 효율적으로 제어해야 한다. 음성을 부호화할 때, 묵음검출 기능을 이용하는 HCDM 부호기를 사용하면, 재래의 HCDM 보다 잡음에 대한 신호비를 6dB 만큼 증가시킬 수 있거나, 전송속도를 1/3가량 줄일 수 있다.In this paper we exploit the use of the intermittent property of speech to reduce the transmission rate or to increase signal-to-quantization noise ratio (SQNR) in coding speech by hybrid companding data modulation (HCDM). In this scheme we detect silence in speech by a speech/silence discriminator. HCDM coding is done only for speech portion. For silence that is detected in evert block of 5 ms, only the information indicating that the Since the HCDM coder transmits bina교 signal synchronously at a fixed rate, the use of a buffer and its efficient control is essential. By using the HCDM with silence detection in coding speech, we could improve SONR by as much as 6 dB over the conventional HCDM or reduce the transmission rate by one third of the HCDM rate.

• 한국병원경영학회지
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• 제14권4호
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• pp.149-162
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• 2009

The purpose of this study is to design strategic hospital service based on each hospital's features. For this study, an assessment was conducted by 398 in-patents of one university hospital located in Seoul. The self-questionnaires, which were investigated from Oct. 15th to 29th in 2008, compared central reception desk with ward reception desk in satisfaction and re-use rate of patients. The major results of this study are as follow. First, according to each reception desk user, they have different satisfaction of it. As for the staff kindness, admission procedure, discharge procedure and manner of staff, those made patients be gratified as well. Second, when it comes to the intention of re-use, there were no significant features between them. Only convenience in admission and discharge procedure, however, was an attractive factor for the recommendation. Third, this study found out the reasons for higher re-use rate of central reception desk users. Regarding service, they were contented with the time for test and treatment. As for the hospital service, they would like to re-use this hospital because of convenient steps of paying interim fee and getting certificates. Forth, this study found out the reasons for higher re-use rate of ward reception desk users. As a point of hospital service view, they responded that respected privacy, hospital facility and general service were good for staying. As for the manner of staff, they mentioned nurses and staff in charge and whole staff members were kind. When it comes to the procedures of patient management, steps of discharge and paying interim fee were convenience. In conclusion, the results of this study suggest that providing a ward reception desk service can boost the satisfaction and re-use rate of in-patients. Furthermore, this strategic management method would be good for not only cutting the moving line but also efficient in-patient care system. These results can be used for the strategic hospital marketing field, as well. Even though this study has a limitation of the targeted populations which were only in a ward reception desk running hospital, it can say that having competitiveness in satisfaction of hospital service is good for promoting and differencing each hospital. Consequently, whole general management system would be adjusted first for differencing each hospital; however, this sort of additional factor should be concerned as well. I expect that this study would give meaningful data for designing strategic and differencing marketing method to lots of hospitals.

• 한국환경생태학회지
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• 제22권6호
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• pp.632-639
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• 2008

기러기류의 분포양상과 시기에 따른 분포변화에 대한 연구를 2006년 10월부터 2007년 3월까지 천수만 부남호와 간월호에서 실시하였다. 기러기류는 주간에 주로 농경지에 분포하였으며, 해안에서는 관찰되지 않았다. 격자별 최대개체수를 이용한 분포도에서, 농경지에서 관찰된 기러기류는 부남호와 간월호 지역 모두 면적이 넓은 지역에 대한 분포비율이 높았다. 특히, 잠자리지역인 저수지와 가까운 지역의 취식비율이 높았다. 기러기류의 주간 취식지는 부남호와 간월호 모두 초기 10월에는 잠자리 지역인 저수지 인근 농경지를 이용하였지만, 월동 중기 1월 이후에는 잠자리에서 먼 지역을 취식지로 이용하였다. 월동말기인 3월에는 개체수 규모가 크게 줄어들고 잠자리에서 먼 지역의 농경지를 더 높은 비율로 이용하였다. 저수지에서 가까운 1km 이내 지역의 평균 개체수가 다른 지역에 비하여 높았다. 월동초기($10{\sim}11$월)에는 저수지 인근지역이 취식지로 선호되었지만, $12{\sim}1$월 그리고, $2{\sim}3$월로 갈수록 평균 서식개체수의 차이가 감소하여 유의한 차이가 없었다. 1km 이내의 격자지역은 초기에 매우 높은 서식지 이용률을 보이지만 차차 감소하여 2월 이후 다시 증가하였다. 반면, 저수지로부터 2km 이상 떨어진 지역은 초기에 매우 낮은 서식지 이용률을 보이지만, 점차 증가하여 1월말에 최대 이용률을 보이고, 이후 점차 감소하였다. 1km 이상2km 미만에 해당하는 지역은 초기에 2km 이상지역보다 이용률이 높고, 1km 미만의 지역보다 낮은 서식지 이용률을 보이지만 11월까지 증가하다가 점차 감소하는 양상을 보였다. 본 연구결과는 기러기류의 취식지 선택이 잠자리와의 거리에 영향을 받으며, 취식무리의 체류 시간에 따라서 먹이량이 감소하여 취식지 선택 양상이 변화하는 것을 보여준다.

• 한국제4기학회지
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• 제17권2호
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• pp.123-128
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• 2003

This study was conducted to examine the water use efficiency (WUE) in five species of one-year-old seedlings grown in a field nursery in Mongolia. Larix sibirica and Pinus sylvestris are the most dominant coniferous species while Ulmus pumila is an important deciduous species known well-adapted in harsh conditions such as in semi-arid forests and Gobi desert regions. Caragana arborescens (Siberian pea shrub) and Hippophae rhamnoides are N-fixing shrubs in Mongolia. Thirty one-year-old seedlings were sampled from each of the five species (a total of 150 samples) and measured for net photosynthetic rate (Pn) and transpiration rate (E). The Pn and E were used to calculate and compare the WUE of each species. Pn differed significantly among the five species (p < 0.05). However, there was no significant difference in Pn between L. sibirica and H. rhamnoides (p > 0.05). C. arborescens showed the highest Pn whereas U. pumila did the poorest. E differed significantly among the five species (p < 0.05). L. sibirica and U. pumila showed considerably lower E than other species. Thus, WUE values of coniferous species such as L. sibirica and P. sylvestris were significantly greater than deciduous or shrub species such as U. pumila, C. arborescens and H. rhamnoides (p < 0.01). It may result that conifers showed relatively high water use efficiency than deciduous or shrub trees due to their lower transpiration rates, which resulted in morphological and physiological characteristics of their leaves. This may indicate that L. sibirica and P. sylvestris can be widely used for rehabilitation works in Mongolia attributed to their dominant distributions but also their high drought-resistance properties.