• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.939-943
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• 2007

Two experiments were conducted to determine the lysine requirement of straight-run broiler chickens ($Hubbard{\times}Hubbard$) during the period 4-21 (Exp. 1) and 21-40 (Exp. 2) days of age. Experiments were conducted during the summer months (June-August) in open-sided houses, thus exposing chicks to chronic heat stress. Daily min-max temperature averaged $28-40^{\circ}C$ (Exp. 1) and $28-36^{\circ}C$ (Exp. 2). Lysine deficient basal diets were formulated to contain low-nutrient-density, i.e., 2,700 kcal per kg ME, 18.6% CP (Exp. 1), and 2,750 kcal per kg ME, 17.1% CP (Exp. 2), to mimic typical commercial broiler diets used in Pakistan. Diets were supplemented with L-lysine HCl to provide total lysine level ranging from 0.85 to 1.10% (six increments) and 0.72 to 1.02% (six increments), respectively in Exp. 1 and 2. Live performance data were subjected to quadratic analysis and requirement was defined as the level achieving 95% of maximum or minimum values. Lysine requirements were found to be 0.98 and 0.97% total lysine, respectively, for gain and feed efficiency during 4-21 days, and 0.87% total lysine for both gain and feed efficiency during 21-40 days of age. Calculated on a digestible lysine basis, the estimates were 0.85 and 0.84%, respectively, for gain and feed efficiency during 4-21 days of age; and 0.75% for gain and feed efficiency during 21-40 days of age.

• 한국산업정보학회논문지
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• 제13권4호
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• pp.24-34
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• 2008

이 연구는 모바일 비즈니스의 진화과정과 환경변화를 다각적이고 복합적으로 분석하여 향후 모바일콘텐츠 비즈니스의 진화방향을 예측함과 동시에 성공적인 전략을 도출하는데 그 목적이 있다. 결론적으로 모바일콘텐츠(MC) 비즈니스 모델은 세대를 거듭해가면서 영역이 확대되고, 그에 따른 사업자의 진출도 늘어남에 따라 복합적이고 다각적으로 변해 가면서 새로운 비즈니스 전략과제를 제시하고 있는데, 첫째, 고객접근성을 강화해야 하며, 둘째, 감성적으로 접근해야 하며, 개방적인 비즈니스 모델이 필요하다. 넷째, 소비자의 니즈를 반영한 콘텐츠의 기획 및 제작이 필요하며, 다섯째, 모바일플랫폼 선도형 콘텐츠군의 개발과 CP의 비즈니스모델 다양화가 요구된다. 산업정책 차원에서는 모바일콘텐츠 산업의 지속적인 발전을 위해서 단기적이고 단면적인 정책이 아닌, 지속가능한 미래 지향적인 정책이 마련되어야 한다. 건전하고 활기찬 모바일콘텐츠 생태계 조성을 위해서 정부와 규제기구는 모바일콘텐츠 시장의 주도자이기보다는 환경 조성자 역할에 충실하는 것이 바람직하다. 즉, 시장의 원활한 작동을 위한 기본적인 제도와 질서를 형성하고 관리하는데 주력해야 할 것이다.

• 전자공학회논문지
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• 제51권3호
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• pp.202-209
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• 2014

본 논문에서는 원형편파 패치안테나에 상부덮개를 여러 층으로 적층함으로써 안테나 성능에 미치는 영향을 분석하였다. 지금까지 원형편파 패치안테나를 설계하기 위해서는 주로 단층의 상부덮개를 적용하거나, 여러 층으로 구성된 하나의 상부덮개를 적용하였고, 성능 분석시 안테나 축비를 거의 고려하지 않았다. 먼저, 상부덮개와 패치안테나 간의 공기층 높이에 의한 중심주파수의 변화를 분석하였다. 공기층 높이가 적을 때는 중심주파수가 낮은 쪽으로 천이하였고, $005{\lambda}_0$의 공기층 높이에서는 주파수 천이가 거의 없었다. 다음은 최적의 공기층 높이를 적용하여 상부덮개의 층수를 증가하면서 안테나 성능을 분석하였다. 상부덮개의 층수가 증가하면서 안테나 이득은 비례적으로 증가하지만, 안테나 축비는 점차적으로 악화되었다. 또한, 상부덮개의 유전체 두께가 증가할수록 안테나 이득은 증가하지만 안테나 축비는 급격히 악화되었다. 결과적으로 안테나 축비를 3dB 이내로 유지하면서 상부덮개의 층수를 확장하여 다양한 이득을 얻을 수 있는 안테나 설계가 가능함을 확인하였다.

• Earthquakes and Structures
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• 제13권2호
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• pp.151-164
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• 2017

This article aims to investigate the possible retrofitting of a deficient building with soft story failure mode by connecting it to an adjacent building which is designed based on current code with friction dampers at all floors. Low cost and high performance reliability along with significant energy dissipation pertaining to stable hysteretic loops may be considered in order to choose the proper damper for connecting adjacent buildings. After connecting two neighbouring floors by friction dampers, the sliding forces of dampers at various stories are set in two arrangements: uniform sliding force and then variable sliding force. In order to account for the stochastic nature of the seismic events, incremental dynamic analyses are employed prior and after the installation of the friction dampers at the various floors. Based on these results, fragility curves and mean annual rate of exceedance of serviceability and ultimate limit states are obtained. The results of this study show that the collapse mode of the deficient building can affect the optimum arrangement of sliding forces of friction dampers at Collapse Prevention (CP) performance level. In particular, the Immediate Occupancy (IO) performance level is not tangible to the sliding force arrangement and it depends solely on sliding force value. Generally it can be claimed that this rehabilitation scheme can turn the challenge of pounding two adjacent buildings into the opportunity of dissipating a large amount of the seismic input energy by the friction dampers, thus improving significantly the poor seismic performance of the deficient structure.

• Asian-Australasian Journal of Animal Sciences
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• 제26권7호
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• pp.995-1002
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• 2013

The effect of conjugated linoleic acid (CLA) feeding on growth performance and fatty acid profiles in thigh meat of broiler chicken was investigated using meta-analysis with a total of 9 studies. Overall effects were calculated by standardized mean differences between treatment (CLA fed) and control using Hedges's adjusted g from fixed and random effect models. Meta-regression was conducted to evaluate the effect of CLA levels. Subgroups in the same study were designated according to used levels of CLA, CP levels or substituted oils in diets. The effects on final body weight, weight gain, feed intake and feed conversion ratio were investigated as growth parameters. Total saturated and unsaturated fatty acid concentrations and C16:0, C18:0, C18:2 and C18:3 concentrations in thigh meat of broiler chicken were used as fatty acid profile parameters. The overall effect of CLA feeding on final weight was negative and it was only significant in fixed effect model (p<0.01). Significantly lower weight gain, feed intake and higher feed conversion ratio compared to control were found (p<0.05). CLA feeding on the overall increased total saturated fatty acid concentration in broilers compared to the control diet (p<0.01). Total unsaturated fatty acid concentration was significantly decreased by CLA feeding (p<0.01). As for individual fatty acid profiles, C16:0, C18:0 and C18:3 were increased and C18:2 was significantly decreased by CLA feeding (p<0.01). In conclusion, CLA was proved not to be beneficial for improving growth performance, whereas it might be supposed that CLA is effective modulating n-6/n-3 fatty acids ratio in thigh meat. However, the economical compensation of the loss from suppressed growth performance and increased saturated fatty acids with the benefit from enhanced n-6/n-3 ratio should be investigated in further studies in order to propose an appropriate use of dietary CLA in the broiler industry.

• 한국시뮬레이션학회논문지
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• 제30권1호
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• pp.55-63
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• 2021

본 논문은 전투 시뮬레이션 상에서 모의되는 무기체계의 방호성능에 대한 연구로, 입사각도에 따른 방호성능의 개선효과를 제시하고자 하였다. 이를 위해, 여러 속도로 발사된 5.45 mm 보통탄을 사용한 소화기 위협에 대하여 일반적으로 사용되는 균일압연강판 재질의 장갑판 3종의 완전 및 부분관통 여부를 판정하는 실사격 탄도실험이 수행되었다. 주요 실험 변수는 무기체계 장갑의 재질 그리고 탄자의 입사각도이었다. 또한, 방호성능에 대한 정량적인 분석을 위하여 기존 세 가지 방호한계속도 측정방법들이 사용되었다. 그 결과 탄자의 입사각이 30도인 경우 장갑의 방호성능은 0도인 경우 대비 재질별 1.04배부터 1.14배까지 향상되었으며, 방호효과가 평균적으로 약 1.1배 개선되는 것을 확인하였다. 이러한 실험결과는 장갑판의 방호성능을 증진시키는 변수에 반영되어 보다 현실에 가까운 전투 시뮬레이션을 개발하는데 기여할 것으로 기대된다.

• Steel and Composite Structures
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• 제23권1호
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• pp.95-105
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• 2017

The use of superelastic shape memory alloys (SMAs) as reinforcements in concrete structures is gradually gaining interest among researchers. Because of different mechanical properties of SMAs compared to the regular steel bars, the use of SMAs as reinforcement in the concrete may change the response of structures under seismic loads. In this study, the effect of SMAs as reinforcement in concrete structures is analytically investigated for 3-, 6- and 8-story reinforced concrete (RC) buildings. For each concrete building, three different reinforcement details are considered: (1) steel reinforcement (Steel) only, (2) SMA bar used in the plastic hinge region of the beams and steel bar in other regions (Steel-SMA), and (3), beams fully reinforced with SMA bar (SMA) and steel bar in other regions. For each case, columns are reinforced with steel bar. Incremental Dynamic Analyses (IDA) are performed using ten different ground motion records to determine the seismic performance of Steel, Steel-SMA and SMA RC buildings. Then fragility curves for each type of RC building by using IDA results for IO, LS and CP performance levels are calculated. Results obtained from the analyses indicate that 3-story frames have approximately the same spectral acceleration corresponding with failure of frames, but in the cases of 6 and 8-story frames, the spectral acceleration is higher in frames equipped with steel reinforcements. Furthermore, the probability of fragility in all frames increases by the building height for all performance levels. Finally, economic evaluation of the three systems are compared.

• Natural Product Sciences
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• 제25권2호
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• pp.111-114
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• 2019

The herbal formula, DF-02, consisting of Ephedra intermedia and Rheum palmatum are used for the treatment of the metabolic diseases such as obesity and liver fibrosis in Korean local clinics. We aimed to develop the simultaneous analytical conditions for four standards, (+)-pseudoephedrine (PSEP) and (-)-ephedrine (EP) for E. intermedia, and aloe-emodin (AE) and chrysophanol (CP) for R. palmatum using HPLC-UV techniques. The validated conditions yielded the high precision (relative standard deviation (RSD) < 3.65%) and the recoveries (94 - 106%) using the calibration curves with high linearity ($R^2$ > 0.9994). As a result, four standards of DF-02 were simultaneously determined under the developed method, which will be utilized for the quality control or evaluation of DF-02 and many herbal preparations containing E. intermedia and R. palmatum.

• 근관절건강학회지
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• 제21권2호
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• pp.153-163
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• 2014

Purpose: This study was to analyze the job of coordinators working in the regional cardiocerebrovascular center. Methods: Using Developing a Curriculum (DACUM) method, the role of coordinators was defined and their duties and tasks were identified. The developed duties and tasks were classified and validated according to importance, difficulty, and frequency of the job. Results: A coordinator is defined as a clinical nurse specialist affiliated in a cardiocerebrovascular center. The coordinator is responsible for managing the major critical pathway to provide adequate medical service and providing education to the patient with myocardial infarction and cerebrovascular attack admitted via emergency room for prevention and management of disease. Ten duties and sixty-nine tasks were identified on the DACUM chart which represented the importance, difficulty, and frequency of tasks showed as A, B, C respectively. Based on determinant coefficient of the task, the highest ranked task was 'analysis for variation of CP' and the lowest was'investing the articles in stock'. Conclusion: The results of study showed that coordinators were doing various duties and tasks and they felt burden from their work and were in confusion. The results of this study can be used to develop training programs for coordinators and evaluation-scale of the coordinators' job performance as the basic data.

• 한국군사과학기술학회지
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• 제20권6호
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• pp.752-757
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• 2017

새로운 공정으로 제작한 금속판재(MMC)가 운동에너지탄을 막는 부가방호구조로 적용가능성을 확인하기 위해 고속충돌시험 및 수치계산으로 평가연구를 수행하였다. 충돌속도는 1.3 km/s 이상에서 우선적으로 수직충돌상황만 고려하였다. 연강의 반무한판에 대한 침투깊이를 기준값으로 설정하고 새로운 부가장갑을 설치하는 경우에 대해 침투깊이 및 질량효율을 비교 검토하였다. MMC판재의 제작은 한국재료연구소에서 이루어졌으며, 이 재료에 대한 고속변형 물성은 포항공과대학에서 수행되었다. 결과는 다음과 같이 요약된다. (1) 연강 반무한판에 세라믹 판재를 부가하는 것만으로도 방호성능 감소 없이 중량이득이 나타난다. (2) 세라믹 판재 앞뒷면에 연성의 금속을 추가 부가하면 중량 증대 없이도 방호성능은 다소 증가하였다. 이는 세라믹을 감싸는 효과가 일부 나타난 것으로 판단된다. (3) 세라믹 판재 앞뒷면에 부가된 연성의 금속을 MMC로 변경한 경우 방호성능 감소 없이 방호성능이 추가적으로 다소 증대되었다. 이것은 단순 연성의 금속보다는 연성과 취성을 모두 지니는 MMC가 바람직한 역할을 수행하였다고 보인다. 즉 세라믹을 감싸는 encapsule 효과 및 탄 저지력이 우수한 세라믹의 취성이 동시에 나타남을 의미한다. (4) 마지막으로 현재의 자료만으로는 강화재로 SiC와 B4C중에 우열을 가리기에는 미소한 차이만 발생하기에 부족함이 있다.