• 한국작물학회지
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• 제29권1호
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• pp.102-107
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• 1984

자가불화합성 작물인 스테비아는 순도를 유지하기 위하여 삽목에 의해 번식하고 있으나 그 소요기간과 증식률이 낮다. 본 실험에서는 액아로부터 완전한 식물계로 분화시켜 대량 증식을 위한 기내배양조건을 알고자 하였으며 그 결과를 요약하면 다음과 같다. 1. Murashige-Skoog(MS) 기본 배지에 NAA와 kinetin을 단독 처리할 때 액아로부터 shoot분화가 가장 좋은 경우는 NAA는 0.01-0.05mg/${\ell}$의 범위였고, kinetin은 0.5-1.0mg/${\ell}$의 범위이었다. 2. MS배지에서 shoot분화는 NAA 0.01-0.05mg/${\ell}$와 kinetin 0.5-1.0mg/${\ell}$을 조합처리하였을 때 좋았다. 3. MS배지의 salt strength를 달리할 때 1$\times$MS가 $\frac{1}{2}$XMS보다 shoot분화와 생육에서 좋을 결과를 보였다. 그러나 root분화는$\frac{1}{2}$XMS에서 높았다. 4. 이상의 결과로보아 스테비아는 단시일 내에 많은 양을 증식시킬 수 있으며 shoot분화와 root 분화시 배지의 염류농도와 홀몬농도를 달리하는 것이 효율적이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권9호
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• pp.4398-4417
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• 2017

Multi-user Multiple-Input and Multiple-Output (MU-MIMO) has potential for prominently enhancing the capacity of wireless network by simultaneously transmitting to multiple users. User selection is an unavoidable problem which bottlenecks the gain of MU-MIMO to a great extent. Major state-of-the-art works are focusing on improving network throughput by using Channel State Information (CSI), however, the overhead of CSI feedback becomes unacceptable when the number of users is large. Some work does well in balancing tradeoff between complexity and achievable throughput but is lack of consideration of fairness. Current works universally ignore the rational utilizing of time resources, which may lead the improvements of network throughput to a standstill. In this paper, we propose TOUSE, a scalable and fair user selection scheme for MU-MIMO. The core design is dynamic-time-warping-based user selection mechanism for downlink MU-MIMO, which could make full use of concurrent transmitting time. TOUSE also presents a novel data-rate estimation method without any CSI feedback, providing supports for user selections. Simulation result shows that TOUSE significantly outperforms traditional contention-based user selection schemes in both throughput and fairness in an indoor condition.

• 한국초지조사료학회지
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• 제21권2호
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• pp.89-96
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• 2001

Carbohydrate and soluble protein reserves and regrowth characteristics in response to cutting height were investigated over four regrowth cycles of turf-type perennial ryegrass(Lolium perenne L. cv. preludeII). When the plants were at the full-vegetative stage (twelve weeks-old), three sequential defoliations at 3, 6 and 9 cm above the root base were imposed at 2-week intervals. Shoot dry weight in all three treatments continuously decreased with progressing regrowth cycle and the decreasing rate was higher as cutting height was lowered. TNC (total non-structural carbohydrate) in stubble at the end of the fourth regrowth cycle in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 27%, respectively, comparing the initial content. TNC in roots also largely decreased with similar pattern in response to cutting height, whereas the absolute amount was much less compared to stubble. Soluble protein in stubble in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 57%, respectively, at the end of fourth regrowth. A significant correlations between TNC (r=0.906) or protein (r=0.879) at the fourth defoliation and dry weight of regrowing shoots at the end of fourth regrowth were observed. these results indicated that cutting height closely influences the levels of organic reserves available for new growth, and that the levels of reserves might provide a useful tool as a determinant for regrowth dynamics.

• 한국정보통신학회논문지
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• 제15권10호
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• pp.2100-2112
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• 2011

직교부호 도약 다중화기술(Orthogonal Code Hopping Multiplexing)은 CDMA기반 이동통신시스템에서 가용한 직교부호의 수보다 많은 수의 사용자를 수용하기 위해 제안된 통계적다중화기반 하향링크 기술이다. 본 논문에서는 최근 다양한 이동통신시스템에 제안되고 있는 다중안테나 기술인 MIMO기술을 사용하여 기존의 직교부호 도약 다중화기술의 성능을 향상시키는 기술을 제안한다. 각 변조된 심벌은 N번 반복되고 반복된 기 심볼은 N개의 송신 안테나로 동시에 전송된다. 반복을 통하여 기존 직교부호 도약 다중화 기술에서 제기되었던 천공(Perforation)의 영향은 반복된 심볼로 분산된다. 반복된 모든 심볼이 모두 천공될 확률은 급격히 줄어드는 것을 확인할 수 있다. 본 논문에서는 시뮬레이션을 통하여 다중안테나를 이용하여 기존의 직교부호 도약 다중화기술이 가지고 있던 단점이 보상될 수 있음을 보인다.

• 한국항공우주학회지
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• 제43권11호
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• pp.963-970
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• 2015

본 연구에서는 압전유압펌프의 챔버부, 체크밸브, 부하, 펌프구동제어기 등 유압펌프 전체 구성품의 해석 모델링을 통하여 브레이크용 소형 압전유압펌프의 가압 동특성을 해석하였다. 가압 동특성을 해석하기 위해 먼저 적층형 압전작동기가 챔버내에서 압력을 형성하는 과정을 모델링하였다. 체크밸브 개도에 따른 유량계수 식을 얻기 위해, 유한요소코드 해석을 통해 체크밸브 압력분포 및 유동결과를 얻은 후 체크밸브 유량계수식을 커브 피팅으로 유도하였다. 또한 부하압력을 피드백 받아 작동기 입력전압을 제어하여 부하압력이 입력명령 압력을 잘 추종하도록 펌프구동제어기를 설계하였다. 시뮬레이션 결과 브레이크 작동에 필요한 정상작동압력까지 도달하는데 걸리는 시간은 약 0.03ms 정도이다. 본 연구에서 얻어진 해석 시뮬레이션 결과는 실제 실험결과와 비교를 통해 타당성을 검증하였다.

• 보건행정학회지
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• 제9권4호
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• pp.15-40
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• 1999

To assess the university health service organization(UHSO) and its school health programs a questionnaire survey for all of 186 four-year colleges in Korea was conducted from December 1. 1998 to March 31. 1999. The response rate was 91.9 percent(171 universities). The UHSO was established in 116 universities(67.8%L The most common name of UHSO. used in 61 universities(52.6%). was school health center. Only 45(38.8%) of the 116 universities surveyed had a committee to support and run the UHSO. The percentage of universities that had committee was higher in national universities and those with a large number of students. The average number of staff working in the UHSO was 3.5; 4.6 in national universities; and 7.1 in universities with more than 15.000 students. There were 43 universities(37.1%) which had a part-time physician and 104 universities (89. 7%) had full-time nurses. Only 4 universities(3.4%) had a independent facility for the UHSO while most of UHSO were housed in other building. The UHSO had an independent budget in 86 universities(74.1%). The average budget per university was 46.890.000 won: private universities had more budget with 59.170.000 won on average than national universities with 36.990.000 won. The average budget allocated per student was 4.362 won. A regular physical examination was performed in 72 universities(62.1%). The percentage of university that performed regular physical examination was higher in private universities than in national universities. Health counseling was performed in 113 universities(97.4%) and vaccinations in 87 universities(75.0%). Medical care services were performed in 87 universities(75.0%). and the private universities and those with over 10.000 students provided the student with more services. Environmental sanitation was executed in 73 universities(62.9%) and health education was conducted in 68 universities(58.6%)' The school health management activities were promoted in 104 universities(89.7%) out of 116 universities with UHSO. Only 12 universities(10.3%) published reports on the achievements and performance of the UHSO. Only 29 universities(25.0%) had a continuing education for employees of the UHSO.

• 보건행정학회지
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• 제21권2호
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• pp.159-178
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• 2011

Korea ranks high among the OECD member countries with a high out-of-pocket share. In 2006, the government implemented in full scale the policy of extending the health insurance benefit coverage. Included in the policy are lowering the out-of-pocket share of patients of serious case and expanding the medical bill ceiling system to mention just a few. This study proposes to confirm effectiveness of the benefit extension policy by identifying changes in 'out-of-pocket expenditure as a share of the ability to pay' and 'incidence rate of catastrophic health care expenditure' of each individual household as manifested before and after the benefit extension policy was implemented. The 1st and 3rd year data from the Korea Welfare Panel Study (KoWePS), conducted by the Korea Institute for Health and Social Affairs (KIHASA), were used for the analysis, where low-income households and ordinary households are sampled separately. While the absolute amount of 'out-of-pocket expenditure' occurred to the average household increased for the period 2005-2007, the 'out-of-pocket expenditure as a share of the ability to pay' decreased. At the same time, the share decreased in the case of low-income households and households with patients of chronic or serious case as contrasted with ordinary households. 'Incidence rates of catastrophic health care expenditure' of ordinary households for 2007 stood at 14.6%, 5.9% and 2.8% at the threshold of 10%, 20% and 30%, respectively. The rates decreased overall between 2005 and 2007, while those of low-income households with patients of serious case statistically significantly increased. An analysis of this study indicates that it is related with the medical bill ceiling system regardless of incomes introduced in 2007.

• 보건행정학회지
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• 제23권3호
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• pp.224-232
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• 2013

Background: This study was a comparative analysis of the major curriculum for 2-year, 3-year, and 4-year colleges of the department of health administration in Korea. Methods: Among 45 Korean colleges registered with the department of health administration as of 2012, finally 25 colleges were selected by establishing the department of health administration more than 5 years ago, excluding government's financial support, and taking regional locations into account. Results: First, generally 2-year colleges was not the relationships between organizational philosophy/purposes and major course in comparison to those of 3-year or 4-year colleges. Second, the composition of credits in the major course appears to be higher for 3-year, 2-year, and 4-year colleges, respectively. Third, subjects related to basic medicine and medical records were included more often in 2-year, 3-year, and 4-year colleges, respectively, and health policy issues were covered more in 4-year, 3-year, and 2-year colleges, respectively. Fourth, the number of students per full-time professor in 2-year colleges was much higher than that in 3-year and 4-year colleges, and the employment rate of graduates for 4-year colleges was found to be higher than that for 2-year and 3-year colleges. Conclusion: Although this study has limitations with regard to the selection of research subjects, it provides baseline data for establishing the health administration required for training competent future professionals.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권6호
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• pp.1848-1868
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• 2014

Multiple-in multiple-out (MIMO) in long-term evolution (LTE) is an essential factor in achieving high speed data rates and spectral efficiency. The unexpected growth in data rate demand has pushed researchers to extend the benefits of multi-user MIMO. The multi-user MIMO system can take full advantage of channel conditions by employing efficient adjustment techniques for scheduling, and by assigning different modulation and coding rates. However, one of the critical issues affecting this feature is the appropriate estimation of channel quality indicator (CQI) to manage the allocated resources to users. Therefore, an accurate CQI estimation scheme is required for the multi-user MIMO transmission to obtain significant improvements on spectral efficiency. This paper presents overviews of multi-user MIMO in LTE/LTE-advanced systems. The link adaptation, scheduling process, and different factors that affect the reliability of CQI measurements are discussed. State-of-the-art schemes for the post-processing CQI estimation, and the comparisons of various CQI estimation schemes to support multi-user MIMO are also addressed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.139-142
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• 2003

Traditionally, the thickness of fire protection materials of structural elements such as beam and column have been decided by fire test using the predominant steel section of $H-300{\times}300{\times}10{\times}15$ for column and $H-400{\times}200{\times}8{\times}13$ for beam in Korea. But this way of determination of fire protection thickness yields very unduly results. Because the temperature-increment rate of structural steel elements depends mainly on magnitude of their cross-areas. In general, the thicker size of cross-areas for structural elements, the lower temperature shows up. It had already proved that the fire protection thickness only depends on the size of cross-areas and the fire protection method for three-fide or four-side exposed conditions in European countries, the United State of America and so on. To demonstrate there would be differences among various cross-areas for structural elements, we conducted several fire tests with full-scale specimens of beams and columns. For the determination of critical temperature for steel section when the fire resistant performance is needed to be decided, we conducted with a loaded fire test for beam and column, respectively. The small column in 1.0 meter length and beam in 1.5 meter length were used in order to deprive the rational fire protection thickness of structural elements such as beam and column, respectively. After test, we could obtain there were significant temperature lass between higher cross-areas and lower cross-areas. The critical temperature of steel as a criterion is used 538$^{\circ}C$ for column and 593$^{\circ}C$ for beam which is from ASTM E 119 because we don't make provisions as critical temperature by elements. We could consider that the best way of determination of fire protection thickness is using the following multi-regression equation which was deprived from several fire tests using the concept of section factor, FR(column) = 0.17 +5191.49t A/Hp + 40.77t, FR(beam) = 0.25 +6899.31t A/Hp + 32.60t(where, FR means fire resistant time, t means thickness, A means cross-area and Hp means heated parameter).