• 한국균학회지
• /
• 제43권2호
• /
• pp.133-136
• /
• 2015

We investigated endophytic fungi diversity of two Pinaceae species (Pinus densiflora, Pinus rigida) and one Cupressaceae species (Juniperus rigida) on Mt. Seodae, Korea. In total, 34 isolates were obtained from 19 host plants and identified according to internal transcribed spacer (ITS) region. As a result, they were placed in 13 taxa. Among them, 52.9% belonged to Leotiomycetes, 32.3% belonged to Sordariomycetes, 5.8% belonged to Agaricomycetes, and 3.0% for isolates belonged to either Eurotiomycetes, Dothideomycetes or Ustilaginomycetes. In particular, Lophodermium growing in pine would be an especially important instance of biodiversity for endophytes, suggesting that further study examining its ecological function in the environment is critical.

• 한국시뮬레이션학회논문지
• /
• 제9권4호
• /
• pp.67-75
• /
• 2000

Often system analysts are interested in the estimation of percentile for system performance. For instance, in PERT network system, the percentile that the project. Typically the control variate method is used to reduce the variability of mean response using the correlation between the response and the control variates with a little additional cost during the course of simulation. In the same spirit, we apply this method to estimate the percentile of project completion time in PERT system, and evaluate the efficiency of the controlled estimator for its percentile.1 Simulation results indicate that the controlled estimators are more effective in reducing the variances of estimators than the simple estimators, however those tend to a little underestimate the percentiles for some critical values. We need more simulation experiments to examine such a kind of bias problem. We expect this research presents a step forward in the area of variance reduction techniques of stochastic simulation.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2006년도 추계학술대회 논문집
• /
• pp.387-391
• /
• 2006

Insight into behaviour of pedestrians as well as tools to assess passenger flow conditions are important in for instance planning and geometric design of railway station under regular and safety-critical circumstances. Algorithm for passenger flow analysis based on DEM(Discrete Element Method) is newly developed. There are lots of similarity between particle-laden two phase flow and passenger flow. The velocity component of 1st phase corresponds to the unit vector of calculation cell, each particle to passenger, volume fraction to population density and the particle velocity to the walking velocity, etc. And, the walking velocity of passenger is also represented by the function of population density. Key algorithms are developed to determine the position of passenger, population density and numbering to each passenger. To verify the effectiveness of new algorithm, passenger flow analysis for the basic models of railway station is conducted.

• 보건행정학회지
• /
• 제31권2호
• /
• pp.145-147
• /
• 2021

The ethical environment in academic research is rapidly changing at a global level. Further, social expectations and public interest toward research ethics are also escalating in Korea. Understanding and applying ethical issues in academic research has become increasingly important. To conform to such changes in the ethical environment, the official journal of the Korean Academy of Health Policy and Management has been consistently establishing and modifying rules and principles regarding research ethics. For instance, we amended the submission guidelines to further address the policies for gendered innovations. For this editorial of the current issue, we would like to organize and share several ethical concerns, which recently gained considerable attention. We hope this review provides scholars with practical guidelines to comprehend and incorporate critical ethical issues into academic research.

• 한국지능정보시스템학회:학술대회논문집
• /
• 한국지능정보시스템학회 2007년도 한국지능정보시스템학회
• /
• pp.389-398
• /
• 2007

Case-based reasoning (CBR) is one of the most popular prediction techniques for medical diagnosis because it is easy to apply, has no possibility of overfitting, and provides a good explanation for the output. However, it has a critical limitation - its prediction performance is generally lower than other artificial intelligence techniques like artificial neural networks (ANNs). In order to obtain accurate results from CBR, effective retrieval and matching of useful prior cases for the problem is essential, but it is still a controversial issue to design a good matching and retrieval mechanism for CBR systems. In this study, we propose a novel approach to enhance the prediction performance of CBR. Our suggestion is the simultaneous optimization of feature weights, instance selection, and the number of neighbors that combine using genetic algorithms (GAs). Our model improves the prediction performance in three ways - (1) measuring similarity between cases more accurately by considering relative importance of each feature, (2) eliminating redundant or erroneous reference cases, and (3) combining several similar cases represent significant patterns. To validate the usefulness of our model, this study applied it to a real-world case for evaluating cytological features derived directly from a digital scan of breast fine needle aspirate (FNA) slides. Experimental results showed that the prediction accuracy of conventional CBR may be improved significantly by using our model. We also found that our proposed model outperformed all the other optimized models for CBR using GA.

• 한국건축시공학회지
• /
• 제21권5호
• /
• pp.397-408
• /
• 2021

건설업은 업무상 재해 발생빈도와 사망자 수가 다른 산업군에 비해 높아 가장 위험한 산업군으로 불린다. 정부는 건설 현장에서 발생하는 산업 재해를 줄이고 예방하기 위해 CCTV 설치 의무화를 발표했다. 건설 현장의 안전 관리자는 CCTV 관제를 통해 현장의 잠재된 위험성을 찾아 제거하고 재해를 예방한다. 하지만 장시간 관제 업무는 피로도가 매우 높아 중요한 상황을 놓치는 경우가 많다. 따라서 본 연구는 딥러닝 기반 컴퓨터 비전 모형 중 개체 분할인 YOLACT와 다중 객체 추적 기법인 SORT을 적용하여 다중 클래스 다중 객체 추적 시스템을 개발하였다. 건설 현장에서 촬영한 영상으로 제안한 방법론의 성능을 MS COCO와 MOT 평가지표로 평가하였다. SORT는 YOLACT의 의존성이 높아서 작은 객체가 적은 데이터셋을 학습한 모형의 성능으로 먼 거리의 물체를 추적하는 성능이 떨어지지만, 크기가 큰 객체에서 뛰어난 성능을 나타냈다. 본 연구로 인해 딥러닝 기반 컴퓨터 비전 기법들의 안전 관제 업무에 보조 역할로 업무상 재해를 예방할 수 있을 것으로 판단된다.

• 인터넷정보학회논문지
• /
• 제20권3호
• /
• pp.77-84
• /
• 2019

Workflow management system is a system that manages the workflow model which defines the process of work in reality. We can define the workflow process by sequencing jobs which is performed by the performers. Using the workflow management system, we can also analyze the flow of the process and revise it more efficiently. Many researches are focused on how to make the workflow process model more efficiently and manage it more easily. Recently, many researches use the workflow log files which are the execution history of the workflow process model performed by the workflow management system. Ourresearch group has many interests in making useful knowledge from the workflow event logs. In this paper we use XES log files because there are many data using this format. This papersuggests what are the cardinalities of the temporal workcases and how to get them from the workflow event logs. Cardinalities of the temporal workcases are the occurrence pattern of critical elements in the workflow process. We discover instance cardinalities, activity cardinalities and organizational resource cardinalities from several XES-based workflow event logs and visualize them. The instance cardinality defines the occurrence of the workflow process instances, the activity cardinality defines the occurrence of the activities and the organizational cardinality defines the occurrence of the organizational resources. From them, we expect to get many useful knowledge such as a patterns of the control flow of the process, frequently executed events, frequently working performer and etc. In further, we even expect to predict the original process model by only using the workflow event logs.

• Korean Membrane Journal
• /
• 제7권1호
• /
• pp.1-18
• /
• 2005

The permeate flux decline due to membrane fouling can be addressed using a variety of theoretical stand-points. Judicious selection of an appropriate theory is a key toward successful prediction of the permeate flux. The essential criterion f3r such a decision appears to be a detailed characterization of the feed solution and membrane properties. Modem theories are capable of accurately predicting several properties of colloidal systems that are important in membrane separation processes from fundamental information pertaining to the particle size, charge, and solution ionic strength. Based on such information, it is relatively straight-forward to determine the properties of the concentrated colloidal dispersion in a polarized layer or the cake layer properties. Incorporation of such information in the framework of the standard theories of membrane filtration, namely, the convective diffusion equation coupled with an appropriate permeate transport model, can lead to reasonably accurate prediction of the permeate flux due to colloidal fouling. The schematic of the essential approach has been delineated in Figure 5. The modern approaches based on appropriate cell models appear to predict the permeate flux behavior in crossflow membrane filtration processes quite accurately without invoking novel theoretical descriptions of particle back transport mechanisms or depending on adjust-able parameters. Such agreements have been observed for a wide range of particle size ranging from small proteins like BSA (diameter ${\~}$6 nm) to latex suspensions (diameter ${\~}1\;{\mu}m$). There we, however, several areas that need further exploration. Some of these include: 1) A clear mechanistic description of the cake formation mechanisms that clearly identifies the disorder to order transition point in different colloidal systems. 2) Determining the structure of a cake layer based on the interparticle and hydrodynamic interactions instead of assuming a fixed geometrical structure on the basis of cell models. 3) Performing well controlled experiments where the cake deposition mechanism can be observed for small colloidal particles (< $1\;{\mu}m$). 4) A clear mechanistic description of the critical operating conditions (for instance, critical pressure) which can minimize the propensity of colloidal membrane fluting. 5) Developing theoretical approaches to account for polydisperse systems that can render the models capable of handing realistic feed solutions typically encountered in diverse applications of membrane filtration.

• 대한수학교육학회지:학교수학
• /
• 제4권2호
• /
• pp.317-331
• /
• 2002

The purpose of this study is to compare the eighth-grade mathematics textbooks of Korea, Japan on the one hand, and those of the United States and England on the other, and to explore the implications for mathematics education in the East and the West. As a result, the dichotomy between the East and the West were set up with the sacrifice of the details. First, the textbook development and publication policies of the East are characterized as uniformity, and those of the West are diversity. Second, for the choice of content, the East and West can be represented by essential and discretionary respectively. Third, the physical appearance of Eastern textbooks is rather plain while that of the Western textbooks is colorful, Fourth, in terms of the characteristics of the content, the dichotomies between the East and the West are linear vs. spiral, content vs. context, formal abidance vs. metacognitive shift, and simple vs. realistic. Each of the Eastern and Western approaches has its own weak points as well as its strong points. For instance, textbooks In the West may help students realize how useful mathematics can be in their lives, but if the link between a mathematical concept and the corresponding real life situation is not made clear, sometimes students may not be able to completely grasp the mathematical concept. In turn, the Eastern textbooks may succeed In conveying ideas in an economical way, but they often fail to motivate students to follow the course. Therefore it is important to take a critical view of each approach. It is through a critical understanding of the differences between different cultures that we are able to learn from each other and to put the results of such comparative studies to better use in the future.

• 한국건설관리학회논문집
• /
• 제8권5호
• /
• pp.182-190
• /
• 2007

국내 중 소규모 건설 산업은 시공분야를 중심으로 발전하여 왔으며 소프트분야가 상대적으로 취약하다. 또한 다양한 발주 체계가 활용되지 못하는 문제점을 안고 진행되고 있다. 더욱이 현재 국내 건설 프로젝트들은 자금력과 기술력을 갖춘 대형 건설업체들이 경쟁 우위를 점하고 있어 중 소규모 건설업체들의 입지가 줄어들고 있다. 최근국내 외 건설시장의 대형화, 고도화와 함께 기술집약적인 공사가 늘어감에 따라 기술경쟁이 가능한 설계시공일괄(Design-Build)방식의 건설 산업이 늘어나고 있는 추세이며 규모가 작은 중 소건설기업의 상황에서는 더욱 건설시장에서 효과적인 경쟁력을 보유하여야 할 것으로 예상한다. 이에 본 연구는 디자인 빌드 방식의 성공요인과 중 소규모 프로젝트 사례조사를 한 후 AHP 분석을 통해 성공요인 도출 및 중요도 분석을 함으로써 중 소규모 건설업체의 디자인 빌드 방식의 성공적 수행을 위한 중점 관리요인을 제시하고자 한다. 그리하여 향후 중 소 건설업체의 발전과 생산성 향상을 위한 기반을 제공하고자 한다.