PV와 BESS를 이용한 복합배전계통의 정상상태 특성 해석

이수용(Soo-Yong Lee),박수영(Soo-Young Pak),이문석(Mun-Seok Lee),노대석(Dae-Seok Rho),김응상(Eung-Sang Kim) 한국산학기술학회 2014 한국산학기술학회 학술대회 Vol.- No.-

태양광전원(PV)이 계통에 연계됨에 따라 전압변동과 전력품질에 문제가 발생되고 있다. 이에 전기저 장장치(BESS)를 이용하여 이런한 문제들을 해결하기 위한 방안이 제시되고 있으나 체계적인 분석이 미흡한 실정이다. 따라서 본 논문에서는 PV와 BESS가 연계된 복합배전계통을 PSCAD/EMTDC를 이 용하여 모델링을 수행하였고, 시험장치를 제작하여 PV출력과 BESS의 충·방전상태에 따른 전압변동특 성과 역률변동시험을 수행한 결과, 본 연구에서 제시한 방안의 유용성을 확인하였다.

수요관리용 전기저장장치(BESS)의 경제성 평가에 관한 연구

최성식(Sung-Sik Choi),박재범(Jea-Bum Park),태동현(Dong-Hyun Tae),박수영(Soo-Young Pak),노대석(Dae-Seok Rho) 한국산학기술학회 2014 한국산학기술학회 학술대회 Vol.- No.-

최근 전기 사용량이 증가하면서 전력수요와 공급능력의 불균형으로 인하여 전력예비율은 점차 감소되고 있으며, 전력 공급의 신뢰성도 떨어지고 있다. 이러한 배경 하에 전기저장장치(Battery Energy Storage System)는 수요관리의 유력한 수단 가운데 하나로써 중요성이 점차 부각되고 있다. 하지만, 이차전지를 이용한 전기저장장치는 아직 고가이므로 전력계통에 도입하여 운용하기 위해서는 경제성 평가가 필수적이다. 따라서, 본 논문에서는 수용가용 BESS의 피크세이빙 및 부하평준화 기능을 통하여 수용가의 기본전기요금과 사용량전기요금을 감소시켜 최대한의 메리트를 추구하는 경제성평가 알고리즘을 제시하였다. 제안한 알고리즘을 이용하여, 수용가(교육기관)를 대상으로 BESS의 경제성을 분석하여, 본 논문에서 제시한 알고리즘의 유용성을 확인하였다.

Comparative double blind test에 의한 抗아메바劑 Ro7-0207(Tiberal), Metronidazole 및 Dehydroemetine의 治效成績의 比較

李午政,全鍾暉,朴弼遠,朴壽泳 대한감염학회 1974 감염 Vol.6 No.1

Introduction New and better substances are still being sought for the treatment of amoebiasis. The aim of this trial is to assess the effectiveness and tolerance of Tiberal and oral dehydroemetine in patients with oligosymptomatic (or mild) intestinal amoebiasis comparing with that of metronidazole which are known to be an active amoebicide. Selection of cases. Lately, classical symptomatic amoebiasis accompanying mucus-bloody stool and tenesmus could be seldom experienced at urban areas in this country. At here the majority of intestinal amebiasis is manifested by loose stools containing mucus, pus or blood (rare), and also by a rapid response to antibioties, but with frequent episods of recurrence caused by diet-failure or alcohol drinking. Among 187 cases of mild enterocolitis which were suspected as being mild intestinal amoebiasis clinically, authors selected amoeba-positive 60 cases and additional 7 cases which were included later in this clinical trial study. The 7 drop-outs in the original study were replaced by these additional 7 cases. The clinical trials were carried out at the St. Mary's Hospital, Catholic Medical College, Seoul, Republic of Korea. During 12 month (April 25, 1973-May 17, 1974), we treated 60 cases of so-called oligosymptomatic amoebiasis with above mentioned three amoebicides. 60 ambulatory cases suffering from mild GI troubles were admitted into the trial (liable to recurrent diarrhoeal stools including mucus, or pus with tenesmus, and also to lower abdominal discomfort of mild pain) those were suspected clinically as having intestinal amoebiasis with carriers of E. histolytica (trophozoits and/or cysts in the feces). Oligosymptomatic amoebiasis group, in this clinical trial study, consisted of 34 males and 26 females ranging from 17 to 62 years of age. All were adolescents or adults and their age distribution was shown in Table 1. Methodology on this clinical trials. We have carried out so-called the comparative double blind trials with Tiberal versus Metronidazole versus oral Dehydroemetine in symptomatic amoebiasis of mild grade. The trial drugs were given also without the knowledge of either the one who gave it or the one who got it in this comparative double blind study. Both (drug examiner) doctors and (drug examined) patients have had no knowledge of each drug. Pharmacist responded to doctor's prescription with code numbers. After the completion of the study the exact name of a drug were publically drawn from the code numbers and the purpose of double blind study was attained. In this study an arrangement for a drug administration schedule was set by as pharmacist exclusively. 60 patients were assigned to one of the three drugs by proper randomization so that 20 patients received tiberal and 20 metronidazole and 20 oral dehydroemetine. After the trial, code numbers of the drugs were identified; nos. 1, 6, 10, 14, 19, 23, 25, 27, 28, 29, 33, 34, 35, 36, 44, 45, 47, 51, 53, and 54 were tiberal; 8, 9, 11, 12, 13, 15, 16, 18, 20, 22, 32, 39, 41, 48, 49, 50, 52, 55, 56, and 57 were metronidazole, and nos. 2, 3, 4, 5, 7, 17, 21, 24, 26, 30, 31, 37, 38, 40, 42, 43, 46, 58, 59 and 60 were oral dehydroemetine. Evaluation The therapeutic effects were assessed by the clinical evolution and by stool parasitology (direct examination and concentration method) performed on day 3 and 6 on treatment, and then at the end of treatment (8-10 day) and one month after the initial treatment. This made a total 4 to 5 parasitological examination per patient, including one examination required for diagnosis prior to treatment. At the same time aspect and consistency of the stool were registered. The effect of the drugs on other protozoa found in the stools were also reported. The tolerance were assessed by clinical findings and laboratory studies made in limited cases at least before and after treatment unless otherwise stated. Blood count, BUN, Alkaline phosphatase, SGP, TECG and urinalysis were performed as laboratory controls. Authors have established following evaluation criteria for this clinical study. Radical cure: free of symptoms with no vegetative or cystic forms of E. histolytica in stool on 3 successive tests. Biological cure: no cystic forms of E. histolytica in stool on 3 successive tests, but persistence of some intestinal disturbances. Relapse: apparent cure or improvement (with negative of 3 successive tests) followed by recurrence with vegetative amoeba on direct smear within 30 days. (re-infection may be included) Failure: the trophozoites or cystic form of E. histolytica has persisted for treatment periods, with some intestinal troubles. Methods of treatment and parasitologic examination In each group one third of the patients received 2 capsnles of 250mg. Tiberal thrice daily for 7 days, one third received 2 tablets of 250 mgmetronidazole thrice daily for 7 days, and one third received 2 tablets of 10 mgdehydroemetine thrice daily for 7 days as the only specific drug. No associated drugs were given together for symptomatic relief in all cases. The reason why fixed 7 days dose were delivered to every cases was based on convenience of stool examination and equalizing the number of days for therapy. The therapeutic drugs were delivered usually for 2 days dose (1st prescription), 3 days dose and 2 days dose (3rd prescription) successively, therefore stool examination had been done on 3rd, 6th and 8-10th day of therapy. Clinical results In oligosymptomatic amoebiasis, 20 cases each were treated with doses of 1,500mg/day of Tiberal and metronidozole for 7 days respectively, and 20 cases were treated with doses of 60mg/day of dehydroemetine for 7 days. The total doses administered were 10,5g, 10,5g, and 420mg respectively in a period of 7 days. Among tiberal group 19 cases were found to be negative after therapy whereas there was 1 with parasitological failure. The clinical effect was fast in 95% of the cases. Effective cure was achieved in 17 whereas symptoms persist in 3 patients among 20 cases. There were 1 failure and 2 late relapse. Comparing data of therapeutic results with that of metronidazole and dehydroemetine were shown in Table 2 & 3. Table 3 shows the negativity rate of trophozoits or cystic form of E. histolytica in stools according to therapeutic periods of trial drugs received. The data would indicated that 5 days dose could not be enough to eradicate the parasites even in the susceptible cases. The result data of clinical improvement and clearance of E. histolytica in patient stool among drug trial groups were shown in Table 4. The cases treated with Tiberal showed no clinical signs on average 4,9 days and negative amoeba in stool on average 4,1 days of therapeutic periods, comparing with on average 5,8 days and 4,1 days in metronidazole-treated group, and on average 6,3 days and average 4,5 days in dehydroemetine-treated group respectively. Authors put in order the therapeutic procedures and their result of failed or relapsed cases with unplanned measures in table 5. These data could be obtained after the completion of the comparative double blind study by the code numbers which were publically drawn afterwards. These therapeutic procedures had been made just incidentally, not by prior plan. 2 cases, 4 cases and 3 cases could get finally effective cure by doubling doses of 7 days course of Tiberal, metronidazole and dehydroemetine respectively. 1 failed case treated with dehydroemetine and 1 another failed case with tiberal could get effective cure by additionally receiving metronidazole and dehydroemetine respectively. 2 failed cases treated with metronidazole could be cleared of parasites by adding tiberal effectively. Adverse reactions were noticed in 20% each of the patients treated with Tiberal and also with metronidazole, and 25% of those treated with dehydroemetine. They were all transient and never severe. There was not a single case who was discontinued on therapy owing to its side-effects. No significant change of laboratory data was noticed by the administration of trial drugs. Brief summary Tiberal, metronidazole and dehydroemetine (oral) were all recognized as highly efficacious anti-amoebic drugs in this clinical studies. On account of following standpoints 1) clearance of parasites in stool 2) clinical symptomatic relieving 3) drug tolerance 4) rate of relapse and failure 5) side-effects, Tiberal could be received much more recognition than metronidazole and dehydroemetine did. P. S. Authors has experienced other 10 cases of amoebiasis among in patients (5 moderate severe intestinal amoebiasis, 4 liver abscesses and 1 lung abscess) treated with Tiberal and metronidazole with excellent therapeutic results, without any sequelae or relapse.