• 한국안전학회지
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• 제31권3호
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• pp.34-41
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• 2016

The purpose of this paper is to conduct ETA on six items of ESS: the whole system, battery, BMS, PCS, ESS and cable. To achieve that, ESS work flow and its components are categorized. Based on performance, human, environmental, management, and safety, this paper drew initiation events (IE) and end states (ES). ETA is applied to the main functions of each item, and the end states that may occur in one initiation event are suggested. In addition, detailed classification was performed to induce various end states on the basis of the suggested initiation events ; loss of grid electricity of ESS, loss of battery electricity(DC) of battery, impairment of electric function of BMS, loss of grid electricity(AC) of PCS, loss of data of EMS, Mechanical damage of cable, event sequence analysis conducted on the basis of event trees. If the suggested IEs and ESs are applied on the basis of ESS event cases, it is expected to prevent the same kinds of accident and operate ESS safely.

• 한국군사과학기술학회지
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• 제15권4호
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• pp.424-434
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• 2012

This paper presents a path planning algorithm of the unmanned aerial vehicle for the neutralization of the enemy firepower. The long range firepower of the ememy is usually located at the rear side of the mountain which is difficult to bomb. The path planner not only consider the differential constraints of the Unmanned Aerial Vehicle (UAV) but also consider the final approaching angle constraint. This problem is easily solved by incorporating the analytical upper bounded continuous curvature path smoothing algorithm into the Rapidly Exploring Random Tree (RRT) planner. The proposed algorithm can build a feasible path satisfying the kinematic constraints of the UAV on the fly. In addition, the curvatures of the path are continuous over the whole path. Simulation results show that the proposed algorithm can generate a feasible path of the UAV for the bombing mission regardless of the posture of the tunnel.

• 대한지구과학교육학회지
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• 제3권1호
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• pp.47-54
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• 2010

The purpose of this study is finding examine the Thinking Maps and how to use Thinking Maps effectively in Science Education. The result of this study were as follows: First, There are 8 type Maps, Circle Map, Tree Maps, Bubble Map, Double Bubble Map, Flow Map, Multi Flow Map, Brace Map, Bridge Map. Each Maps are useful in the following activities ; Circle Map-Express their thoughts. Tree Map-Activities as like determine the structure, classification, information organization. Bubble Maps-Construction. Double Bubble Map-Comparison of similarities and differences. Flow Map-Set goals, determine the result of changes in time or place. Multi Flow Map-Analysis cause and effect, expectation and reasoning. Brace Map-Analysis whole and part. Bridge Map-Activities need analogies. Second, each element of inquiry has 1~2 appropriate type of Thinking Maps. So student can choose the desired map. Third, the result of analysing of Science Curriculum Subjects, depending on the subject variety maps can be used. Therefore the Thinking Maps can be used for a variety on activities and subject. And student can be selected according to their learning style. So Thinking Maps are effective to improve student's Self-Directed Learning.

• Journal of Microbiology and Biotechnology
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• 제34권2호
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• pp.296-305
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• 2024

Peach tree gummosis is a botanical anomaly distinguished by the secretion of dark-brown gum from the shoots of peach trees, and Botryosphaeria dothidea has been identified as one of the fungal species responsible for its occurrence. In South Korea, approximately 80% of gummosis cases are linked to infections caused by B. dothidea. In this study, we isolated microbes from the soil surrounding peach trees exhibiting antifungal activity against B. dothidea. Subsequently, we identified several bacterial strains as potential candidates for a biocontrol agent. Among them, Bacillus velezensis KTA01 displayed the most robust antifungal activity and was therefore selected for further analysis. To investigate the antifungal mechanism of B. velezensis KTA01, we performed tests to assess cell wall degradation and siderophore production. Additionally, we conducted reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis based on whole-genome sequencing to confirm the presence of genes responsible for the biosynthesis of lipopeptide compounds, a well-known characteristic of Bacillus spp., and to compare gene expression levels. Moreover, we extracted lipopeptide compounds using methanol and subjected them to both antifungal activity testing and high-performance liquid chromatography (HPLC) analysis. The experimental findings presented in this study unequivocally demonstrate the promising potential of B. velezensis KTA01 as a biocontrol agent against B. dothidea KACC45481, the pathogen responsible for causing peach tree gummosis.

• 한국안전학회지
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• 제35권1호
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• pp.107-115
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• 2020

This paper introduces the first vital area identification (VAI) process for the physical protection of nuclear power plants (NPPs) during low power and shutdown (LPSD) operation. This LPSD VAI is based on the 3rd generation VAI method which very efficiently utilizes probabilistic safety assessment (PSA) event trees (ETs). This LPSD VAI process was implemented to the virtual NPP during LPSD operation in this study. Korea Atomic Energy Research Institute (KAERI) had developed the 2nd generation full power VAI method that utilizes whole internal and external (fire and flooding) PSA results of NPPs during full power operation. In order to minimize the huge burden of the 2nd generation full power VAI method, the 3rd generation full power VAI method was developed, which utilizes ETs and minimal PSA fault trees instead of using the whole PSA fault tree. In the 3rd generation full power VAI method, (1) PSA ETs are analyzed, (2) minimal mitigation systems for avoiding core damage are selected from ETs by calculating system-level target sets and prevention sets, (3) relatively small sabotage fault tree that has the systems in the shortest system-level prevention set is composed, (4) room-level target sets and prevention sets are calculated from this small sabotage fault tree, and (5) the rooms in the shortest prevention set are defined as vital areas that should be protected. Currently, the 3rd generation full power VAI method is being employed for the VAI of Korean NPPs. This study is the first development and application of the 3rd generation VAI method to the LPSD VAI of NPP. For the LPSD VAI, (1) many LPSD ETs are classified into a few representative LPSD ETs based on the functional similarity of accident scenarios, (2) a few representative LPSD ETs are simplified with some VAI rules, and then (3) the 3rd generation VAI is performed as mentioned in the previous paragraph. It is well known that the shortest room-level prevention sets that are calculated by the 2nd and 3rd generation VAI methods are identical.

• 한국토양비료학회지
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• 제33권5호
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• pp.325-332
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• 2000

1998년 11월 18일에 $2.7{\times}2.7m$ 거리로 재식된 11년생 궁천조생온주 4주에 5 atom % 15N를 요소로 19.68 g 주-1의 N, $58kg\;ha^{-1}$의 $K_2O$을 시용하였고, 1999년 3월 22일에 104, 308, $62kg\;ha^{-1}$의 N, $P_2O_5$, $K_2O$를 6월 12일에 42 and $83kg\;ha^{-1}$의 N와, $K_2O$를 시용하여 재배한 후 1999년 6월 15일과 12월 8일에 각각 2주씩 굴취 해체하여 전질소 및 가을시용질소 함유량을 수체 부위별로 조사하였다. 과실, 잎줄기, 뿌리에의 전질소함유량의 분포비율은 6월 굴취 때에 각각 주당 전질소 총함유량(168.2g)의 11.9, 42.1, 29.7, 16.3%이었고, 12월 굴취 때에 각각 주당 전질소 총함유량 (169.8g)의 27.6, 36.4, 22.8. 13.1%이었다. 수체 질소 중 가을시용질소에서 유래된 질소의 비율은 두 굴취 시기 모두 새로 발생된 기관에서 현저히 높았다. 6월 굴취 때의 가을시용질소 회수율은 18.5%(3.63g 주-1)이었고, 주당 가을시용질소 총함유량의 21.1, 50.4, 21.5, 7.9%가 각각 과실 잎, 줄기, 뿌리에 분포되어 있었다. 12월 굴취 때의 가을시용질소 회수율은 17.0%(3.35g 주-1)이었고 가을시용질소 총함유량의 39.6, 40.5, 14.5, 5.3%가 각각 과실, 잎, 줄기, 뿌리에 분포되어 있다. 전질소에 비하여 두 시기 모두 가을시용질소에서 유래된 질소는 대사적으로 활발한 조직에 보다 많이 축적된 반면 오래된 조직에는 보다 적게 축적되었다.

• 한국산학기술학회논문지
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• 제14권7호
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• pp.3400-3411
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• 2013

본 연구의 목적은 회복실 환자의 평균 체류시간을 알아보고, 체류시간에 미치는 요인들을 파악하여 회복실 체류 시간 예측을 위한 분석을 하기 위함이다. 본 연구의 대상자는 상급 종합병원에 입원한 전신 마취 하에 일반외과 수술을 받은 18세 이상 성인 남녀 환자 중 회복실로 입실한 환자를 1,500명을 대상으로 하였고 이중 1,293건을 분석하였다. 회복실 체류시간에 영향을 미치는 요인으로 32항목을 측정하였다. 평균 회복실 체류시간은 72.02분이었다. 수술주기별 관련요인과 회복실 체류시간의 관계를 살펴본 결과 나이, 수술종류, 수술시간, 진통제사용회수가 유의미한 관계를 나타내었다 회복실 체류시간에 가장 영향을 많이 주는 변수는 수술종류이며 그 다음 EKG 이상여부, 나이, 마취제, 수술시간으로 나타났다. 범주 I(30분~60분)은 2개의 경우, 범주 II(61분~90분)도 2개의 경우, 범주 III(91분~120분)은 4개의 경우로 분석되었다.

• 대한전기학회논문지:전력기술부문A
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• 제49권10호
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• pp.516-523
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• 2000

In this paper, intelligent methods using digital protective relay in power supervisory control system is developed in order to protect power systems by means of timely fault detection and diagnosis during operation for induction motor which has various load environments and capacities in power systems. The spectrum pattern of input currents was used to monitor to state of induction motors, and by clustering the spectrum pattern of input currents, the newly occurrence of spectrums pattern caused by faults were detected. For diagnosis of the fault detected, the fuzzy fault tree was derived, and the fuzzy relation equation representing the relation between an induction motor fault and each fault type, was solved. The solution of the fuzzy relation equation shows the possibility of each fault's occurring. The results obtained are summarized as follows: 1) The test result on the basis of KEMC1120 and IEC60255, show that the operation time error of the digital motor protective relay is improved within ${\pm}5%$. 2) Using clustering algorithm by unsupervisory learning, an on-line fault detection method, not affected by the characteristics of loads and rates, was implemented, and the degree of dependency by experts during fault detection was reduced. 3) With the fuzzy fault tree, fault diagnosis process became systematic and expandable to the whole system, and the diagnosis for sub-systems can be made as an object-oriented module.

• 한국콘텐츠학회논문지
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• 제11권1호
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• pp.56-64
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• 2011

스트림데이터는 무한하고 연속적인 특성을 지니고 있기 때문에 전체 데이터를 기반으로 빈발 항목 집합을 탐사하는 것은 어렵다. 이 때문에 데이터의 특성과 사용자의 특성을 반영한 특수한 데이터마이닝 방법이 필요하다. 이 논문에서는 사용자가 최근에 발생한 데이터에 더 많은 관심이 있다는 특성을 반영하여 빈발 항목을 탐사하는 FIMWB 방법을 제안한다. FIMWB는 과거 데이터의 발생 시점과 현재 시점과의 시간 간격에 따라 가변적인 가중치를 배치에 부여하여 최신 데이터에 더 많은 관심과 중요성을 반영한다. FP-Digraph는 FIMWB를 통해 탐사된 빈발 항목으로 그래프를 구성하여 빈발 항목 집합을 탐사한다. 실험 결과로 FIMWB 방법이 불필요한 항목의 생성을 감소시키고 트리기반(FP-Tree)의 빈발 항목 집합 탐사에 비해 제안하는 FP-Digraph 방법이 스트림 데이터 환경에 더 적합함을 알 수 있다.

• 한국수자원학회논문집
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• 제41권8호
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• pp.797-806
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• 2008

본 연구에서는 특정 해상도상에서 정의되는 유역의 모든 배수경로들로 구성되는 배수망을 도시하여 자연유역의 배수구조에 대한 기하학적 특성을 분석하여 보았다. 이를 위하여 Fractal 나무와 Horton의 법칙을 기반으로 분기에 의하여 조직되는 망상구조에 대하여 이론적 고찰을 수행하였다. 배수망의 작도에는 ArcGIS를 적용하였고 작도된 배수망에 대하여 Strahler의 차수기법에 따라 위상구조를 수립하여 차수별 배수구조의 기하학적 특성을 분석하고자 시도하여 보았다. Richardson의 방법에 따라 배수구조의 Fractal 특성을 분석해 본 결과 지표면유동과 하천유동 사이에는 개별적인 거동특성이 존재할 수 있음을 볼 수 있었고 자연유역의 하천망은 공간을 채워가는 Fractal 도형임을 확인할 수 있었다. 본 연구의 결과로부터 지표면유동을 포함한 망상구조에 대한 Fractal 이론을 실제유역에 적용하였을 경우 지금까지의 경험식에 의한 차수법칙과 상이한 결과를 나타냄을 알 수 있었다. 이의 결과들은 추후 망상구조의 결정에 크게 기여될 수 있으리라 판단된다.