• 임산에너지
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• 제22권3호
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• pp.29-36
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• 2003

본 논문은 중국 장백산 북사면의 5가지 산림 군집에서 우세목의 잎 내 질소 환원 효소의 활성도를 보다 개량된 방법을 적용하여 측정 분석한 내용을 다루었다. 질소 환원 효소의 활성도는 수목의 내음성과 연관이 깊은 것으로 파악되어, 양수일수록 질소 환원 효소의 활성도가 높은 것으로 측정되었다. 또한 질소 환원 효소의 활성도는 산림내의 수직적 구조와 생태적 입지 조건과 연관이 깊은 것으로 나타났다. 질소 환원 효소의 활성도가 높은 수종들은 생장이 빠르고 생산력이 높은 것으로 판단된다.

• 한국철도학회논문집
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• 제11권6호
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• pp.530-535
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• 2008

대구지하철 화재사고 이후 많은 화재안전대책에 대한 연구가 수행중이나, 안전대책의 효과에 대한 정량적 분석이나 다양한 대책이 조합되어 사용될 경우의 효과에 대한 연구는 미흡한 실정으로 화재안전대책의 중복투자가 발생할 수 있다. 본 연구에서는 다양한 화재안전대책의 연관성을 분석하고 안전대책이 위험도 경감에 미치는 영향을 정량적으로 평가하기 위해 주요 영향인자와 대책을 고장수목과 사건수목으로 구성하였다. 본 연구 결과는 향후 위험도 평가과정에서 안전대책의 민감도 분석이나 비용효과 분석 등에 활용될 수 있다.

• 한국도로학회논문집
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• 제20권3호
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• pp.27-37
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• 2018

PURPOSES : The objective of this study is to develop a pavement rehabilitation decision tree considering current pavement condition by evaluating severity and distress types such as roughness, cracking and rutting. METHODS : To improve the proposed overall rehabilitation decision tree, current decision tree from Korea and decision trees from other countries were summarized and investigated. The problem when applying the current rehabilitation method obtained from the decision tree applied in Seoul was further analyzed. It was found that the current decision trees do not consider different distress characteristics such as crack type, road types and functions. Because of this, different distress values for IRI, crack rate and plastic deformation was added to the proposed decision tree to properly recommend appropriate pavement rehabilitation. Utilizing the 2017 Seoul pavement management system data and considering all factors as discussed, the proposed overall decision tree was revised and improved. RESULTS :In this study, the type of crack was included to the decision tree. Meanwhile current design thickness and special asphalt mixture were studied and improved to be applied on different pavement condition. In addition, the improved decision tree was incorporated with the Seoul asphalt overlay design program. In the case of Seoul's rehabilitation budget, rehabilitation budget can be optimized if a 25mm milling and overlay thickness is used. CONCLUSIONS:A practical and theoretical evaluation tool in pavement rehabilitation design was presented and proposed for Seoul City.

• 한국정보과학회논문지:데이타베이스
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• 제35권3호
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• pp.218-230
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• 2008

시간지원 데이타베이스 시스템에서의 시간 집계 연산은 일반적인 집계 연산의 확장으로써, 집계의 범위 조건에 '시간'을 포함한다. 시간 집계 연산은 이력 데이타 웨어하우스, 전화 기록 관리(CDR) 등에 유용하다. 본 논문에서는 질의 조건에 여러 개의 선택 프레디키트들을 포함하는 시간 집계 연산을 효율적으로 처리하기 위한 자료 구조인 ITA-tree를 제안하고, 이를 이용한 시간 집계 처리 기법을 제안한다. ITA-tree에서는 레코드의 시간 구간을 T-value라는 하나의 값으로 변환한 후, $B^+$-tree와 비슷하게 이 값을 이용하여 색인을 생성한다. 또한, 많은 레코드가 동일한 T-value 값을 가지게 되는 핫-스팟 문제를 위해 개선된 ITA-tree인 eITA-tree를 제안한다. 본 논문에서는 제안된 기법들의 성능을 분석과 실험을 통해 비교한다.

• Journal of Forest and Environmental Science
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• 제40권2호
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• pp.111-117
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• 2024

An evaluation was carried out on variability in morphology of fruits and seeds (number and weight) of Tetrapleura tetraptera (Schumach. and Thonn.) Taub. from different populations across its distribution range in Nigeria. Bulk fruit samples were collected and examined for variations in morphological characters. Differences in morphological character of fruits and seeds among the populations were determined using analysis of variance at 5% level of probability. The relationships among morphological characters were determined using Pearson correlation coefficient (r). Significant variations (p<0.05) existed among T. tetraptera populations for all the evaluated characters: fruit length, fruit width, number of seeds per fruit and seed weight. A positive significant strong correlation (r=0.96) was found between seed weight and number of seeds per fruit, while no correlation existed between fruit length, width and number of seeds. Seed weight was positively correlated with minimum altitude (r=0.97) and maximum altitude (r=0.99) of seed populations. Number of seeds was also significantly correlated with maximum altitude (r=0.965). There was no significant correlation between geo-climatic variables and fruit dimensions (length and width). Observed variations in morphological traits within and across populations of T. tetraptera may be used as proxy to estimate genetic diversity and selection of superior trees for improved productivity.

• 한국의료질향상학회지
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• 제8권2호
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• pp.186-207
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• 2001

Background : This study presented an analysis of healthcare quality indicators using data mining and a development of decision support system for quality improvement. Method : Specifically, important factors influencing the key quality indicators were identified using a decision tree method for data mining based on 8,405 patients who discharged from a medical center during the period between December 1, 2000 and January 31, 2001. In addition, a decision support system was developed to analyze and monitor trends of these quality indicators using a Visual Basic 6.0. Guidelines and tutorial for quality improvement activities were also included in the system. Result : Among 12 selected quality indicators, decision tree analysis was performed for 3 indicators ; unscheduled readmission due to the same or related condition, unscheduled return to intensive care unit, and inpatient mortality which have a volume bigger than 100 cases during the period. The optimum range of target group in healthcare quality indicators were identified from the gain chart. Important influencing factors for these 3 indicators were: diagnosis, attribute of the disease, and age of the patient in unscheduled returns to ICU group ; and length of stay, diagnosis, and belonging department in inpatient mortality group. Conclusion : We developed a decision support system through analysis of healthcare quality indicators and data mining technique which can be effectively implemented for utilization review and quality management in a healthcare organization. In the future, further number of quality indicators should be developed to effectively support a hospital-wide Continuous Quality Improvement activity. Through these endevours, a decision support system can be developed and the newly developed decision support system should be well integrated with the hospital Order Communication System to support concurrent review, utilization review, quality and risk management.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (2)
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• pp.508-510
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• 2004

컴포넌트 기반 기술의 장점을 최대로 살리기 위해서는 컴포넌트 기반 개발 프로세스 및 관리 프로세스가 체계적으로 통합 관리되어야 한다. 체계적인 개발 프로세스의 부재 속에서 개발된 컴포넌트는 자신의 최대 이점인 소프트웨어의 재사용과 품질의 향상을 끌어내지 못하기 때문이다. 이에 본 리포트에서는 체계적인 개발 프로세스에 대한 Opportunity Tree를 제안함으로써 컴포넌트를 개발하고자 하는 이들의 CBD에 대한 이해를 높이고, 개발 과정의 주요 프로세스를 효과적으로 수행할 수 있도록 한다.

• 전자공학회논문지CI
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• 제47권5호
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• pp.25-34
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• 2010

스타이너 포인트들을 추가하여 모든 입력 노드들을 최단 길이로 연결하는 스타이너 최소 트리는 최소 신장 트리에 비해 전체 길이는 짧으나, 그것을 생성하는 문제는 NP-Complete 영역에 속한다. 이 문제를 위한 휴리스틱들은, 입력 노드의 수가 매우 큰 경우에는 많은 시간과 계산을 요구한다. 본 논문에서는 많은 입력 노드에 대해, 최하위 계층에서 포탈을 이용한 모든 가능한 단위 스타이너 트리들을 생성하고 각 상위 계층에서 이들을 계층별 병합 처리하여 최상위 계층에서 최소 비용의 트리를 선택하는 효과적인 PTAS 기법을 제안한다. 16,000개의 입력 노드와 최하위 계층에서 16개의 단위 영역으로 설계된 실험에서 생성된 PTAS 스타이너 트리는, pure 스타이너 트리의 길이에 비해 길이가 0.24% 증가되었으나, 생성 시간은 직렬 처리는 85.4%, 병렬처리는 98.9% 개선되었다. 따라서 제안하는 PTAS 스타이너 트리 생성 기법은 많은 입력 노드들에 대해 근사 스타이너 트리를 신속히 생성하는 응용에 잘 적용될 수 있을 것이다.

• 한국환경과학회지
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• 제31권9호
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• pp.735-741
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• 2022

Global warming affects forests and their ecology. Diversity in the forest is a buffer that reduces the damage due to global warming. Mixed forests are ecologically more valuable as versatile habitats and are effective in preventing landslides. In Korea, most forests were created by simple afforestation with trees of evergreen species. Typically, evergreen trees are shallow-rooted, and deciduous trees are deep-rooted. Mixed forest tree roots grip the soil effectively, which reduces the occurrence of landslides. Therefore, improving the distribution of tree types is essential to reduce damage due to global warming. For this improvement, the investigation of tree types of the forest is needed. However, determining the tree type distribution of forests that are spread over wide areas is labor-intensive and time-consuming. This study suggests effective methods for determining the distribution of tree types in a forest that is spread across a relatively wide area. Using normalized difference vegetation index and RGB images from unmanned aerial vehicles, each evergreen and deciduous tree, and grassland area can be distinguished. The distinguished image determines the distribution of tree type. This method is effective compared to directly determining the tree type distribution in the forest by the use of manpower. The data from these methods could be applied to plan a mixed forest or to prepare for future damage due to global warming.

• Journal of Plant Biotechnology
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• 제48권3호
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• pp.173-178
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• 2021

Basal callus formation and leaf abscission is a problem in clonal micropropagation. We have described an in vitro clonal propagation protocol of Dalbergia sissoo Roxb (shisham) 'FRI-14' in which AgNO₃ played important role not only in mitigating problem of leaf abscission and basal callus, but also improved shoot induction and multiplication. Best induction and shoot multiplication was obtained on MS media with 1.5 mg/l 6-BAP and 10 mg/l AgNO₃ and half-strength MS media with 0.5 mg/l 6-BAP, 2 mg/l AgNO₃ and 50 mg/l Adenine sulphate whereas best ex vitro rooting was obtained with 200 mg/l IBA in pulse treatment.