• 한국약용작물학회지
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• 제14권2호
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• pp.107-112
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• 2006

Two Atractylodes species, A. japonica Koidz. ex Kitam. (AJ) and A. macrocephala Koidz (AM) were used in this study. AJ population had higher amounts of Sesquiterpenoids and stronger tolerance to root rot but less vigor of root growth than AM population. Two populations (AJ and AM) were crossed to make interspecific hybrid population. A total of 98 lines propagated clonally were selected from a cross of AJ and AM, and evaluated for contents of sesquiterpenoids, atractylon (ATLN) and atractylenolide III (AT3) using high performance liquid chromatography (HPLC), and growth characters such as plant height, stem number and root weight. HPLC profiles of the hybrids were compared with those of parent plants, and it demonstrated the production of introgression hybrid by crossing between AJ and AM. Of 98 clonal lines,10 lines were selected by 10% level based on the growth vigor and tolerance to root rot, and AJM2102-51 line showed the heaviest root weight (117.1 g/plant) among them. A total of 98 hybrid lines contained on average $0.16\;{\pm}\;0.10\;mg/g$ of $AT3,\;2.00\;{\pm}\;1.37\;mg/g$ of ATLN, and $2.16\;{\pm}\;1.40\;mg/g$ of total sesquiterpenoids, showing high coefficients of variation (above 65%). Ten lines having high contents of sesquiterpenoids were selected, and AJM2101-15 had the highest amount (9.83 mg/g) of ATLN, and showed 40.8 g/plant of root weight similar to mean value (39.9 g/plant) of hybrid lines. The result showed that the introgression of both characters of vigorous growth from AM and high sesquiterpenoids content from AJ could be possible to make new hybrid lines by crossing between AJ and AM.

• 한국초지조사료학회지
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• 제11권1호
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• pp.1-5
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• 1991

Tall fescue(Festuca amndinacea Schreb.) is a productive pasture grass that is widely adapted to the soil and climate of Korea. It is regarded, however, as relatively low in palatability and nutritive value. On the other hand, Italian ryegrass(lo1ium rnultz$om Lam.) is highly nutritious and palatable, but is essentially weak in cold tolerance. Numerous investigators have succeeded in producing hybrids between Lolium spp. and Festuca spp. but no improved varieties have resulted. Therefore, intergeneric hybridization of Italian ryegrass with tall fescue is employed in 1984 to improve the adaptive and cold resistance quality of Italian ryegrass. In the mean time, F1-hybrid plants obtained by crossing Italian ryegrass x tall fescue were observed in open field. The results are summarized as follows: 1. Leaf-size and silica cell hair were intermediate between the types of parents but the shape of auricle tended to show Italian ryegrass and auricle-cilia to show tall fescue. 2. Roots of $F_1$-hybrid plants were mainly distributed at top soil and did not produced florescence material. 3. Head type of hybrids was intermediate between the types of parents but ray length was somewhat less than the length of tall fescue ray. Typical Italian ryegrass or tall fescue-like phenotypes were not observed. 4. Anthers of $F_1$-hybrid plants were formed but pollen were not formed. Even though pollen were formed, they were all empty. 5. Hybrid plants were more winterhardy and summer persistency than Italian ryegrass. They showed a equivalent growth to Italian ryegrass in spring and to tall fescue in summer. 6. Chromosome of $F_1$-hybrids was allopolyploid(2n=4~=28) and all $F_1$-hybrid plants were sterile.

• 응용통계연구
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• 제34권2호
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• pp.153-166
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• 2021

약물유전체학 연구의 주요 목표는 고차원의 유전 변수를 기반으로 개인의 약물 반응성을 예측하는 것이다. 변수의 개수가 많기 때문에 변수의 개수를 줄이기 위해서는 변수 선택이 필요하며, 선택된 변수들은 머신러닝 알고리즘을 사용하여 예측 모델을 구축하는데 사용된다. 본 연구에서는 400명의 뇌전증 환자의 차세대 염기서열 분석 데이터에 로지스틱 회귀, ReliefF, TurF, 랜덤 포레스트, LASSO의 조합과 같은 여러 가지 혼합 변수 선택 방법을 적용하였다. 선택된 변수들에 랜덤포레스트, 그래디언트 부스팅, 서포트벡터머신을 포함한 머신러닝 방법들을 적용했고 스태킹을 통해 앙상블 모형을 구축하였다. 본 연구의 결과는 랜덤포레스트와 ReliefF의 혼합 변수 선택 방법을 이용한 스태킹 모형이 다른 모형보다 더 좋은 성능을 보인다는 것을 보여주었다. 5-폴드 교차 검증을 기반으로 하여 적합한 최적 모형의 평균 검증 정확도는 0.727이고 평균 검증 AUC 값은 0.761로 나타났다. 또한, 동일한 변수를 사용할 때 스태킹 모델이 단일 머신러닝 예측 모델보다 성능이 우수한 것으로 나타났다.

• 한국자동차공학회논문집
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• 제11권5호
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• pp.163-169
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• 2003

Modeling of engine-generator system and its control responses are investigated using high performance generator controller. The nonlinear engine is modeled using mean torque production model based on experimental engine map. In case of diesel engine. the amount of injected fief is decided by engine controller depending on the APS(Acceleration Position Sensor) value. An electromechanical generator model contains electrical circuits and moment of inertia. The generator controller maximizes the performance of generator using decoupling and linearized current feedback control. The generator control system consists of 3-phase IGBT inverter and controller board based on 32 bit floating point DSP. Field oriented control algorithm with digital current feedback control at 10kHz sampling enabled high performance torque and speed control of induction machine. Not only the steady state but also the transient state responses can be evaluated through a batch test of the engine generator system. Developed engine and generator modeling and control can be utilized in various applications such as Series Hybrid Electric Vehicle(SHEV), engine-generator for emergency, and other hybrid generation systems.

• 융합보안논문지
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• 제6권4호
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• pp.91-99
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• 2006

그 동안 이루어진 웹 캐싱에 대한 연구주제는 캐시에 대한 구조적인 접근을 통한 성능의 향상과, 캐싱 기법 자체에 대한 연구, 이들 기법을 혼합적으로 결합한 기법에 대한 연구가 주로 이루어져 왔다. 또한 기존의 웹 객체 참조특성 분석은 웹 로그를 통한 히스토리 분석, 사용자선호도, 데이터마이닝 관점에서의 사용자 특성을 위주로 이루어져왔다. 본 연구에서는 웹 객체참조특성을 확률분포적인 특성 관점에서 분석하며, 이를 통해 객체의 평균수명을 분석하고 이를 웹 캐싱 성능 향상에 도입하는 새로운 연구 방법을 제시한다. 본 연구는 다양한 연구로 발전할 수 있으며, 전자상거래시스템의 성능향상, 지연시간 계산을 통한 고객 만족도의 향상, 웹 로그분석을 통한 데이터마이닝 분야 등 다양한 분야에 대해 연구의 파급 효과가 기대된다.

• 산업경영시스템학회지
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• 제40권4호
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• pp.260-267
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• 2017

Quantum-inspired Genetic Algorithm (QGA) is a probabilistic search optimization method combined quantum computation and genetic algorithm. In QGA, the chromosomes are encoded by qubits and are updated by quantum rotation gates, which can achieve a genetic search. Asset-based weapon target assignment (WTA) problem can be described as an optimization problem in which the defenders assign the weapons to hostile targets in order to maximize the value of a group of surviving assets threatened by the targets. It has already been proven that the WTA problem is NP-complete. In this study, we propose a QGA and a hybrid-QGA to solve an asset-based WTA problem. In the proposed QGA, a set of probabilistic superposition of qubits are coded and collapsed into a target number. Q-gate updating strategy is also used for search guidance. The hybrid-QGA is generated by incorporating both the random search capability of QGA and the evolution capability of genetic algorithm (GA). To observe the performance of each algorithm, we construct three synthetic WTA problems and check how each algorithm works on them. Simulation results show that all of the algorithm have good quality of solutions. Since the difference among mean resulting value is within 2%, we run the nonparametric pairwise Wilcoxon rank sum test for testing the equality of the means among the results. The Wilcoxon test reveals that GA has better quality than the others. In contrast, the simulation results indicate that hybrid-QGA and QGA is much faster than GA for the production of the same number of generations.

• 한국자동차공학회논문집
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• 제19권2호
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• pp.26-34
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• 2011

Hybrid powertrain systems have been developed to improve the fuel efficiency of internal combustion engines. In the case of a parallel hybrid powertrain system, an engine and a motor are directly coupled. Because of the hardware configuration of the parallel hybrid system, friction and the pumping losses of internal combustion engines always exists. Such losses are the primary factors that result in the deterioration of fuel efficiency in the parallel-type hybrid powertrain system. In particular, the engine operates as a power consumption device during the fuel-cut condition. In order to improve the fuel efficiency for the parallel-type hybrid system, cylinder deactivation (CDA) technology was developed. Cylinder deactivation technology can improve fuel efficiency by reducing pumping losses during the fuel-cut driving condition. In a CDA engine, there are two operating modes: a CDA mode and an SI mode according to the vehicle operating condition. However, during the mode change from CDA to SI, a serious fluctuation of the air-fuel ratio can occur without adequate control. In this study, an air-fuel ratio control algorithm during the mode transition from CDA to SI was proposed. The control algorithm was developed based on the mean value CDA engine model. Finally, the performance of the control algorithm was validated by various engine experiments.

• Journal of the Optical Society of Korea
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• 제4권1호
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• pp.30-36
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• 2000

In this paper, a method based on the Genetic Algorithm(GA) for phase optimization is proposed. The programmable hybrid optical interconnection system implemented by the spatial light modula-tor is tested for a near-real-time optical processing. Designed diffractive grating has a 74.7[%] high diffraction efficiency and a $1.73 {\times}10^{-1}$ uniformity quantitatively. The dependence of characteris-tics on several parameters in the grating design are analyzed. Also, as a result of the geometrical transformation to obtain quantitative data for $3 {\times} 3$ spot beams, an objective optical experiment using CCD array detector produces the mean of beam intensity as a gray level of 202, the maximum value is 225, the minimum value is 186, and uniformity is quantitatively $1.93 {\times} 10^{-1}$, similar to the simulation result.

• 농업과학연구
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• 제14권1호
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• pp.98-133
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• 1987

The mechanical and rheological properties of agricultural materials are important for engineering design and analysis of their mechanical harvesting, handling, transporting and processing systems. Agricultural materials, which composed of structural members and fluids do not react in a purely elastic manner, and their response when subjected to stress and strain is a combination of elastic and viscous behavior so called viscoelastic behavior. Many researchers have conducted studies on the mechanical and rheological properties of the various agricultural products, but a few researcher has studied those properties of rice plant, and also those data are available only for foreign varieties of rice plant. This study are conducted to experimentally determine the mechanical and the rheological properties such as axial compressive strength, tensile strength, bending and shear strength, stress relaxation and creep behavior of rice stems, and grain detachment strength. The rheological models for the rice stem were developed from the test data. The shearing characteristics were examined at some different levels of portion, cross-sectional area, moisture content of rice stem and shearing angle. The results obtained from this study were summarized as follows 1. The mechanical properties of the stems of the J aponica types were greater than those of the Indica ${\times}$ Japonica hybrid in compression, tension, bendingand shearing. 2. The mean value of the compressive force was 80.5 N in the Japonica types and 55.5 N in the Indica ${\times}$ Japonica hybrid which was about 70 percent to that of the Japonica types, and then the value increased progressively at the lower portion of the stems generally. 3. The average tensile force was about 226.6 N in the Japonica types and 123.6 N in the Indica ${\times}$ Japonica hybrid which was about 55 percent to that of the Japonica types. 4. The bending moment was $0.19N{\cdot}m$ in the Japonica types and $0.13N{\cdot}m$ in the Indica ${\times}$ Japonica hybrid which was 68 percent to that of the Japonica types and the bending strength was 7.7 MPa in the Japonica types and 6.5 MPa in the Indica ${\times}$ Japonica hybrid respectively. 5. The shearing force was 141.1 N in Jinju, the Japonica type and 101.4 N in Taebaeg, the Indica ${\times}$ Japonica hybrid which was 72 percent to that of Jinju, and the shearing strength of Taebaeg was 63 percent to that of Jinju. 6. The shearing force and the shearing energy along the stem portion in Jinju increased progressively together at the lower portions, meanwhile in Taebaeg the shearing force showed the maximum value at the intermediate portion and the shearing energy was the greatest at the portion of 21 cm from the ground level, and also the shearing strength and the shearing energy per unit cross-sectional area of the stem were the greater values at the intermediate portion than at any other portions. 7. The shearing force and the shearing energy increased with increase of the cross-sectional area of the rice stem and with decrease of the shearing angie from $90^{\circ}$ to $50^{\circ}$. 8. The shearing forces showed the minimum values of 110 N at Jinju and of 60 N at Taebaeg, the shearing energy at the moisture content decreased about 15 percent point from initial moisture content showed value of 50 mJ in Jinju and of 30 mJ in Taebaeg, respectively. 9. The stress relaxation behavior could be described by the generalized Maxwell model and also the compression creep behavior by Burger's model, respectively in the rice stem. 10. With increase of loading rate, the stress relaxation intensity increased, meanwhile the relaxation time and residual stress decreased. 11. In the compression creep test, the logarithmic creep occured at the stress less than 2.0 MPa and the steady-state creep at the stress larger than 2.0 MPa. 12. The stress level had not a significant effect on the relaxation time, while the relaxation intensity and residual stress increased with increase of the stress level. 13. In the compression creep test of the rice stem, the instantaneous elastic modulus of Burger's model showed the range of 60 to 80 MPa and the viscosities of the free dashpot were very large numerical value which was well explained that the rice stem was viscoelastic material. 14. The tensile detachment forces were about 1.7 to 2.3 N in the Japonica types while about 1.0 to 1.3 N in Indica ${\times}$ Japonica hybrid corresponding to 58 percent of Japonica types, and the bending detachment forces were about 0.6 to 1.1 N corresponding to 30 to 50 percent of the tensile detachment forces, and the bending detachment of the Indica ${\times}$ Japonica hybrid was 0.1 to 0.3 N which was 7 to 21 percent of Japonica types. 15. The detachment force of the lower portion was little bigger than that of the upper portion in a penicle and was not significantly affected by the harvesting period from September 28 to October 20. 16. The tensile and bending detachment forces decreased with decrease of the moisture content from 23 to 13 percent (w.b.) by the natural drying, and the decreasing rate of detachment forces along the moisture content was the greater in the bending detachment force than the tensile detachment force.

• 대한소아치과학회지
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• 제28권2호
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• pp.261-270
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• 2001

본 연구에서는 최근 치과임상에서 이용되고 있는 7종의 복합레진을 시험재료로 선택한 다음 법랑질과 복합레진 충전재가 대합하는 경우의 마모 양상을 조사하기 위해 광중합형 복합레진과 제2소구치 교두를 핀-디스크 구동 방식의 전동식 마모시험기에 고정한 다음 68.6N의 하중을 가한 상태에서 30,000회전시켜 $1.3{\times}10^3m$의 미끄럼 접촉을 가하였다. 마모도를 평가하기 위해 복합레진의 종류에 따른 제2소구치 교두의 수직고경 변화, 시편의 두께 감소와 체적 손실 및 마모시험 전후의 표면을 주사전자현미경으로 관찰하였고, 표면경도가 마모도에 미치는 영향을 평가하기 위해 누프 경도를 측정한 결과, 다음과 같은 결론을 얻었다. 1. 누프 경도는 Spectrum 군에서 70.4로 가장 높고 Heliomolar 군에서 19.8로 가장 낮은 값을 보였으며, Tukey 다중범위검증법에 의해서 각 군 사이의 통계적 유의성을 검증한 결과, Spectrum 군, Z100 군 및 Clearfil AP-X 군을 제외한 나머지 모든 군들 사이에서 상호간에 통계학적으로 유의한 차이를 보였다(p<0.05). 2. 법랑질의 내마모성은 microfill 형인 Heliomolar 군과 대합하는 경우에 가장 높게 나타났으며, 구치부용에서는 구상의 zirconia silica 미세 입자를 복합화한 micro hybrid 형의 Palpique 군에서 가장 높게 나타났다. 3. 복합레진의 연마성 마모에 대한 저항성은 필러의 평균 입경이 작고 미세 필러를 고밀도로 분산시켜 복합화한 hybrid 형 복합레진에서 높게 나타나는 경향을 보였다. 4. 주사전자현미경 관찰 결과, 마모면에서는 필러의 돌출, 마멸과 탈락 및 기질레진의 미세 균열 진전과 표면층의 박리 등이 관찰되었다.