• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.186-193
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• 2002

A new integrated torque and speed control algorithm has been proposed for the load balancing of rollers in continuous strip processing line(CSPL). Using the proposed method, the output torque and speed can be controlled to follow the reference in spite of nonideal effects such as the speed reference error and/or the controller gain difference between rolls. This new algorithm can be easily implemented in a motor drive system of each roll as it does not require the torque feedback of the others. Through the simulation and experiments for a simple CSPL consists of four driven rolls, the load balancing performance of the proposed scheme is presented and compared with that of conventional method.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.181-189
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• 2002

The first zoeal stage of Palaemon ortmanni (Rathbun, 1902) is re-described and illustrated in detail from laboratory-hatched material. The first zoeas of Palaemon are more closely related to those of Palaemonetes than to Macrobrachium, Leptocarpus, Leander, Leanderites, and Brachycarpus by having the endopod of maxillule with terminal seta and the endopod of maxilla with 2+1 setae. A provisional key to the zoeas between three genera Palaemon, Macrobrachium, and Periclimenes known from Korean waters is included.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.227-237
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• 2000

Fourteen species of the genus Gonocephalum and one species of the genus Opatrum (Tenebrionidae, Opatrini) from Korea have been previously recorded. They are taxonomically reviewed based on many faunistic reports and research papers. We also examined many specimens including voucher materials of the previous studies. Among the recorded species, G. sabulosum is excluded because it was misidentified for the individual variation of Opatrum subaratum. We couldn’t find any Korean materials of four species (G. japanum, G. bilinearum, G. outreyi, G. malayanum), and used the materials determined from other countries. Key to 13 species of the genus Gonocephalum, illustrations of adults and male aedeagus are provided.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.170-179
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• 1996

누룩은 생소맥을 조분쇄하여 물로 혼합시켜 자연적으로 공지중의 여러 종류의 미생물을 배양시켜 만들었다. 그러므로 누룩에서는 많은 종류의 사상균, 호모와 세균이 증식하였다. 누룩의 당화력은 원료 생소맥의 당화력과 대부분의 사상균의 당화력과 알붕의 세균성 당화력에 기인하여, 발효력은 누룩효모와 극소수의 사상균애 의하여 이루어지고 있다. 1945년 이전까지 누룩으로부터 12속 59종의 사상균이, 8속 29종의 효모와 4속 16종의 세균이 분리 되었다. 누룩사상균은 Aspergillus 속이 주종을 이루었고 Rhizopus속, Absidia속, Nucor속의 순으로 분포하고 있었고, Aspergillus속과 Rhizopus속은 중요한 누룩 당화균으로 작용하였다. 누룩의 대표적 효모는 Saccharomyces cerevisiae 이며 , 이균이 알코올 발효에 가장 큰 역할을 담당하며, Saccharomyces cerevisiae도 전통 민속주의 탁주와 약주의 발효역에 깊이관여한다고 사료된다. 누룩 중에 증식하는 세균은 양조학상 특별한 역할을 담당하지않지만 Bacillus 속 과 젖산세균이 많이 분리되었으며, 젖산세균은 담금초기에 pH의 안정화에 기여할 수 있다고 추측할 수 있다.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.41-46
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• 1996

본 실험은 이병 딸기의 조직에서 분리 동정된 시들음병균(Fusarium oxysporum f. sp. fragariae) 균주들의 유？거 변이를 random amplified polymorphic DNA(RAPD) marker들을 이용하여 조사하였다. 총 24개의 딸기 시들음병 균주들의 DNA를 주형으로 하여 16개의 random 10-mer primer들을 사용하여 증폭시킨 결과 총 231개의 marker들을 이용하여 유전적 변이를 조사해 본 결과 크게 RAPD I과 RAPD II의 2개 그룹으로 나눌 수 있었다. RAPD I그룹에 속하는 균주는 VCG A에 속하는 Y1, K1, K2, K3, K4, N2, N3, N4-1, N6-1, N6-2, N8, N9, N10, M1-2-1 균주, VCG B에 속하는 M4-1 균주 그리고 VCG C에 속하는 N1, Y2 균주들이었고, RAPD II그룹에는 VCG B에 속하는 M1-1, M2-2-1, M2-4-2, M3-2, M3-3-2 균주와 VCG D에 속하는 N1 1 균주가 속하였다. 이들 2그룹 간에는 31%의 유사성이 있었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.967-972
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• 2012

In order to implement good control of the permanent magnet synchronous motor(PMSM), the exact speed and rotor position information is needed.Recently, many studies have performed about sensorless speed control of the PMSM. This paper proposed sensorless speed controls of PMSM by using the Unscented Kalman Filter(UKF).The UKF is designed to eliminate the noise and get to the accuracy value and deals with the estimation of the speed and the rotor position of PMSM. Simulation and experiment have been performed for the verification of the proposed algorithm.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.211-222
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• 1992

The systematic study of freshwater rotifers was conducted with the materials collected from 205 sites in South Korea. As a result, 4 subspecies, 3 from of Family Brachionidae (Keratella, Notholca) was identified; of which, 1 from is new to the Korean fauna: Keratella quadrata f. testudo. Total 135 species, 15 subspecies, 9 varieties and 10 forms representing 14 families 40 genera are now recorded from Korea by adding the 1 from newly described in the present paper.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1151-1158
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• 2020

In order to investigate the speed profile of data I/O of HDD, we have developed an utility program. The application to HDD reveals the detail properties of the speed profile of HDD and the relation between the cylinder structure of HDD and the velocity profile. For the extent application, the experiment of the large volume storage was performed, and the profile of SSD media, which is known as the new rapid media, was measured. The new M.2 NVME SSD, which has the ability of over 10Gbps, we can compare the velocities between cp under linux O/S and the utility, and shows that the performance of the utility can be reliable.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.256-256
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• 2021

Saint-Venant 방정식은 수평규모가 수심규모보다 큰 천수흐름을 기술하는 수리동역학 모형으로 지난 수십년간 공학적 분야에서 널리 이용되어 왔다. 최근에도 기후변화에 따른 도시 홍수의 위기 증대로 홍수위기관리의 관심이 높아짐에 따라 홍수파(flood wave), 도시침수(urban inundation), 돌발홍수(flash flood) 등의 신속한 예측을 위한 Saint-Venant 방정식의 연구가 활발히 진행되고 있다. 그러나 도시와 같은 인공구조물이 즐비한 상황에서 천수흐름을 해석하는 고전적인 수치해법들은 다양한 불연속 지형들의 존재로 인하여 불안정하며 지배방정식의 정해로 수치해가 잘 수렴하지 않는 문제가 있다. 지난 수년간 이를 해결하기 위해 불연속한 지형을 안정적으로 해결할 수 있는 수치기법의 연구가 진행되어 왔으나, 정해로의 수렴성, 정확성에 관하여 연구가 부족한 실정이다. 본 연구는 수치해법의 주요 구조를 구성하는 Saint-Venant 방정식의 불연속한 지형조건에 대한 리만 문제의 정해를 연구하였다. 쌍곡선형 시스템의 특징을 고려하여 요소파들(elementary waves)의 공식을 유도하였는데, 질량과 에너지의 보존법칙에 위배되지 않으며 운동량이송부의 비선형성과 지형의 불연속에 의한 비엄격성을 고려할 수 있는 조건을 제시하였다. 또한, 유도된 요소파들을 바탕으로 L-M & R-M 커브이론(Han et al. 2014)을 사용할 수 있는 조건과 당위성을 증명하였고, 이를 바탕으로 Saint-Venant 방정식의 정해법을 구성하였다. 리만문제의 다양한 초기조건들을 바탕으로 모든 경우의 정해 구조를 조사하였고, 이를 통해 불연속 지형에 대한 Saint-Venant 지배방정식의 정해가 다수해를 갖을 수 있음을 보였으며, 이를 근사할 수 있는 수치기법의 전략을 소개하였다.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.365-374
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• 2007

The purpose of this study is to investigate the students' conceptions about the reaction rate changes during the chemical equilibrium shifts and also whether the questions about basic concepts of the reaction rate are helpful for the students' understanding of reaction rate changes during the chemical equilibrium shifts. The subjects were 100 students in the 12th grade. The questionnaires were composed of A, B, and A' set, which had to be answered sequentially. The A set consisted of questions asking the change of reaction rate when chemical equilibrium was shifted, the B set was to testify the basic concepts of the reaction rate, and the A' set was the same as the A set. The results showed that the students' understanding of the reverse reaction rate change was lower than that of the forward reaction rate change during the equilibrium shift. Also it was found that students' understanding of the reaction rate change caused by adding the reactant was fairly good while their understanding of the reaction rate change caused by temperature increment was very poor. Since the students marked very high scores in the B set questions, their poor understanding for the reaction rate changes during the equilibrium shifts was not seemed to be due to the lacks of the basic knowledge of reaction rate. Instead, it was due to the failure of applying the basic knowledge of reaction rate to the changes of reaction conditions. It was also found that the average scores of A' set were statistically higher than those of A set. It means the B set items were helpful for the students to solve the A' set items. These results evidenced the possibility of set questionnaires could help the students to connect the related concepts in solving the problems.