Phytochemical Constituents of Phyllanthus urinaria

차준민,박종일,최상운,이강노 한국생약학회 2020 Natural Product Sciences Vol.26 No.2

Extensive column chromatography separation of the MeOH extract from the aerial parts of Phyllanthus urinaria afforded seventeen compounds (1 - 17). The structures of the compounds were elucidated by physicochemical and spectroscopic methods to be 5′-β-D-glucopyranosyloxyjasmonic butyl ester (1), (+)- cucurbic acid (2), dendranthemoside B (3), boscialin 4′-O-β-D-glucoside (4), 4,5-dihydroblumenol A (5), (6R,9R)-megastigman-4-ene-9,13-diol (6), (3S,5R,6S,9R)-3,6-dihydroxy-5,6-dihydro-β-ionol (7), (6S,9R)-roseoside (8), mallophenol B (9), icariside B5 (10), corchoinoside B (11), canangaionoside (12), 5,6-epoxy-3-hydroxy-7- megastigmen-9-one (13), icariside B2 (14), (7E)-2β,3β-dihydroxy-megastigm-7-en-9-one (15), betulalbuside A (16), and loliolide (17). The compounds 1, and 3 - 16 were isolated for the first time from this plant. The absolute stereochemistry of compound 1 was newly determined. The isolated compounds were tested for cytotoxic activity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay, but all the compounds showed weak cytotoxic activities.

Cauda Equina Syndrome Caused by a Sacral Insufficiency Fracture in the Lower Part of Zones 2 and 3: A Case Report

차준민,권남우,이수지,이장우 대한근전도전기진단의학회 2021 대한근전도 전기진단의학회지 Vol.23 No.1

Sacral insufficiency fractures (SIFs) often cause referred low back pain, and are rarely accompanied by cauda equina syndrome (CES). We report a case of CES caused by SIF in the lower part of zones 2 and 3, which is not a typical location. A postmenopausal woman often sat on a chair for long periods, and pain in the coccyx and perianal area occurred. After 4 years, during which time the pain worsened and she developed urinary and fecal incontinence, magnetic resonance imaging showed a SIF involving the S3-S5 vertebrae. Prolonged latency of the bulbocavernosus reflex was confirmed through an electrodiagnostic study, and detrusor underactivity was confirmed through a urodynamic study, leading to a CES diagnosis. Unlike typical cases of osteoporotic SIF, the fracture occurred at an atypical location. We believe that long periods of sitting caused a different weight-bearing pattern of the sacrum from that found in typical cases.

Functional Improvement after Taking Rehabilitation Program in Cerebellar Ataxia in a Patient with Systemic Lupus Erythematosus: a Case Report

차준민,김형섭 대한뇌신경재활학회 2020 뇌신경재활 Vol.13 No.2

Cerebellar involvement in systemic lupus erythematosus (SLE) is rare, occurring in less than 2% of cases, with cerebellar atrophy on brain imaging even rarer. We describe a case of cerebellar atrophy in a patient with a history of SLE who underwent an intensive rehabilitation program and achieved functional improvement. A 26-years-old female with SLE felt difficult in balancing as well as dizziness and she took magnetic resonance imaging which showed cerebellar atrophy and positron emission tomography-computed tomography which showed markedly decreased signal intensity at bilateral temporal, parietal lobes, cerebellum and moderately at bilateral frontal lobes. A neurological examination showed bilateral nystagmus, intention tremor, bilateral dysmetria, and bilateral dysdiadochokinesia. Prior to the rehabilitation program, the patient's scores on the Berg Balance Scale (BBS) and Modified Barthel Index (MBI) were 4/56 and 37/100, respectively. The patient was hospitalized twice for rehabilitation treatment, which consisted of physical therapy, occupational therapy, therapeutic pool therapy, and robotic-assisted gait training. At discharge, the patient's BBS score was 9/56, and her MBI score was 46/100, and she was able to walk more than 20 m using an anterior walker. In the final 2 weeks before discharge, the patient was trained in the use of an electric wheelchair for outdoor activity.

위험률 평활화를 이용한 공급능력 산정 방법에 관한 연구

차준민 대진대학교 1996 大眞論叢 Vol.4 No.-

Maintenance scheduling plays an important role in evaluating the supply reliability of power system. There exist many operational constraints to be considered for maintenance scheduling. This paper proposes a new algorithm to evaluate the supply capability via the maintenance scheduling for the alternatives of long-term generation expansion planning by using risk levelization method which is one of the most convenient maintenance scheduling method. We adjust the maintenance scheduling to levelize the reliability over all period. The proposed algorithm is applied to the test system. Finally, we could consider various constraints for the maintenance scheduling of alternatives in the long-term generation expansion planning by using the proposed algorithm.

PowerWorld Simulator를 이용한 전력시스템 해석

차준민 대진대학교 정보통신연구소 1999 정보통신 논문집 Vol.2 No.-

In this paper, the analysis of power system is conducted by using PowerWorld Simulator, which is the one of the most powerful simulation program for power system. Several programs for power system analysis are introduced as compared with PowerWorld Simulator. Numerical results of the power flow calculation of the test system show that PowerWorld Simulator is very effective and useful program for power system analysis.

공급신뢰도 개선을 위한 발전기 보수계획

차준민 한국에너지학회 1998 에너지공학 Vol.7 No.1

Maintenance scheduling of generators plays an important role in evaluating supply reliability of power systems. Since generators must be maintained and inspected, the generation planner must schedule planned outages during the year. Several factors entering into this scheduling analysis include: seasonal load-demand profile, amount of maintenance, size of the units, elapsed time from last maintenance, and availability of maintenance crew. This paper proposes a new maintenance scheduling algorithm for the alternatives of long-term generation expansion planning by using LOLP levelization method which is known as an effective method for the generator's maintenance scheduling. To get the best supply reliability of power systems, we change the maintenance period to levelize the reliability over all period. The proposed algorithm is applied to a real size power system and the better reliability results are obtained. 발전기의 보수계획은 전력계통의 공급신뢰도를 평가하는데 중요한 영향을 미치는 변수이다. 발전기는 반드시 검사와 보수를 해야 하기 때문에, 운전계획을 세울 때 한해의 발전기 정지계획을 고려하여 정해야 한다. 이러한 보수계획을 수립할 대에는 계절적 부하수요특징, 보수용량, 발전기 용량, 지난번 보수로부터의 경과시간 등의 여러 가지 요인들을 고려해야 한다. 본 논문에서는 발전기 보수계획 프로그램중 실용적인 방법으로 알려져 있는 LOLP(Loss of Load Probability) 평활화법을 이용하여 각 연도별 공급신뢰도를 최대로 하여 고려대상 기간 전체의 공급신뢰도를 향상시키는 보수계획 수립 알고리즘을 제안한다. 즉, 전력계통의 더 좋은 신뢰도를 얻기 위하여 전체 기간에 대한 신뢰도가 평활화되도록 보수시기를 변경하였다. 제안한 알고리즘을 실계통에 적용하여 그 유용성을 검증하였다.

최대전력 수송능력 평가에서의 데이터 변환 프로그램 개발에 관한 연구

차준민 대진대학교 1998 大眞論叢 Vol.6 No.-

In this paper, the comparison and analysis of PTI and IEEE data formats are conducted, and the algorithm and the developed program for data conversion between these data formats are proposed. PTI and IEEE data formats are widely used as the input data form of the software program for power systems. However, they are composed of different formation with each other. So, it is necessary to convert between two formats in order to used more programs with different input data format. Numerical results of the power flow calculation of the test system show that developed program are effective and useful.

Phytochemical Constituents of Capsella bursa-pastoris and Their Anti-inflammatory Activity

차준민,김동현,이태현,Lalita Subedi,김선여,이강노 한국생약학회 2018 Natural Product Sciences Vol.24 No.2

Phytochemical investigation of 80% MeOH extract of the aerial parts of Capsella bursa-pastoris yielded fourteen compounds (1 - 14). The structures of the compounds were elucidated by spectroscopic methods to be methyl-1-thio-b-D-glucopyranosyl disulfide (1), 10-methylsulphinyl-decanenitrile (2), 11-methyl-sulphinyl-undecanenitrile (3), 1-O-(lauroyl)glycerol (4), phytene-1, 2-diol (5), (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (6), loliolide (7), b-sitosterol (8), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (9), 1-feruloyl-b-D-glucopyranoside (10), pinoresinol-4'-O-b-D-glucopyranoside (11), luteolin (12), quercetin-3-O-b-D-glucopyranoside (13), and luteolin 6-C-b-glucopyranoside (14). Although compound 1 was reported as synthetic compound, 1 was first isolated from natural source. NMR spectral data assignments of 1, 2 and 3 were reported for the first time, and compounds 1 - 14 were for the first time reported from this plant source. The anti-inflammatory effects of 1 - 14 were evaluated in lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cells. Compounds 12 exhibited strong inhibitory effects on nitric oxide production in LPS-activated BV-2 cells with IC50 values of 9.70 mM.

복합계통의 송전설비 보강계획에 관한 연구

차준민 한국조명전기설비학회 2001 조명·전기설비학회논문지 Vol.15 No.3

본 연구에서는 전원설비와 송전설비를 모두 고려한 복합계통의 송전설비 보강계획을 위한 다양한 판단기준을 정량화하고 불확실한 평가항목을 종합적으로 고려하기 위해 Fuzzy 이론을 도입하여 설비보강계획 대체안중의 최적안을 결정하는 알고리즘을 개발하여 이의 유용성을 검증하였다. 즉, 각 대체안별로 평가항목에 대한 평가 결과를 구하고, 각 평가항목별로 계획입안자가 부여한 중요도에 따른 퍼지측도를 구한다. 이렇게 구한 퍼지측도와 평가치를 Sugeno 퍼지적분을 이용하여 각 대체안별 종합평가치를 구하고, 이 종합평가치가 가장 큰 대체안을 최적안으로 선정한다. 이러한 과정을 통하여 기존의 방법에서 반영할 수 없었던 비용이외의 항목도 고려하여 최적안을 결정할 수 있으며, 또한 평가항목별 중요도를 반영하여 최적안을 결정할 수 있다. 본 알고리즘을 검증하기 위하여 1998년도 한전계통의 345[kV] 선로상정사고 계산결과를 이용하여 최대전력수송능력(MLSC)이 작게 나타나는 경우에 대한 병목구간을 파악하고, 이를 해소하기 위해 실현 가능한 선로보강계획안의 대체안을 상정하였다. 이 대체안은 가공선로, 지중케이블에 대한 증설과 신설을 조합하여 구성하였으며, 이 대체안을 평가하기 위한 평가항목은 건설비, 보수유지비, 선로보강효과, 수용도의 4가지로 정하였다. 상정한 대체안에 본 연구의 알고리즘을 적용하여 최적설비보강계획안을 결정할 수 있었다. Fuzzy theory is used to quantify some subjective criteria and consider uncertain factors for transmission line reinforcement planning in this paper. Sugeno's fuzzy integral is also used in the proposed method, because it can be easily allied to multi attribute decision making problems such as power system planning. To verify the proposed algorithm, some bode-neck lines are searched for the case that the amount of Maximal Load Supplying Capability(MLSC) is small using the results of contingency analysis for Korea Electric Power Corporation(KEPCO)'s 345[kV] transmission line in 1998. And several feasible alternatives are composed for line reinforcement which can dissolve the bottle-neck.

1999년 ICEE를 다녀와서

차준민 대한전기학회 1999 전기의 세계 Vol.48 No.10