• Title/Summary/Keyword: problem analysis

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Cost Estimation Model for Introduction to Virtual Power Plants in Korea (국내 가상발전소 도입을 위한 비용 추정 모델)

  • Park, Hye-Yeon;Park, Sang-Yoon;Son, Sung-Yong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.15 no.2
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    • pp.178-188
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    • 2022
  • The introduction of virtual power plants is actively being discussed to solve the problem of grid acceptability caused by the spread of distributed renewable energy, which is the key to achieving carbon neutrality. However, a new business such as virtual power plants is difficult to secure economic feasibility at the initial stage of introduction because it is common that there is no compensation mechanism. Therefore, appropriate support including subsidy is required at the early stage. But, it is generally difficult to obtain the cost model to determine the subsidy level because of the lack of enough data for the new business model. In this study, a survey of domestic experts on the requirements, appropriate scale, and cost required for the introduction of virtual power plants is conducted. First, resource composition scenarios are designed from the survey results to consider the impact of the resource composition on the cost. Then, the cost estimation model is obtained using the individual cost estimation data for their resource compositions using logistic regression analysis. In the case study, appropriate initial subsidy levels are analyzed and compared for the virtual power plants on the scale of 20-500MW. The results show that mid-to-large resource composition cases show 29-51% lower cost than small-to-large resource composition cases.

A Suggestions of Future Direction of the Integrated Community Care Business for Improvement of the Elderly's Life Care (노인의 라이프케어 향상을 위한 지역사회 통합돌봄사업 미래 방향에 대한 제시)

  • Yang, Seung-Hoon
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.8
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    • pp.423-432
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    • 2021
  • In this study, we investigated and the following conclusions are presented by identifying the current status and problems in order to expand the future's value of the community care project introduced and implemented to improve the quality and care for the elderly's life. First, the needs analysis of the elderly receiving services is composed of patient-centered rather than investigator-centered, and in particular, medical management through medical staff visits should be strengthened, and specialized service items according to gender, age, disability type, and personal preference should be strengthened. This will have to be gradually strengthened. Second, by analyzing the satisfaction, redundancy, and effectiveness of service items, we save money, and consider the consumer-oriented service item composition and application of items necessary for new services. Third, through the introduction of an integrated schedule management system, it is necessary to specialize in pre-booking and visit schedule management between the elderly and the direct service organizations that provide services. Fourth, as an effort to solve the financial problem, it is necessary to prepare a rational resource sharing system with health and medical finance, long-term care insurance system, and social welfare financial project. and it may consider that putting the medical personnel who are from local public medical college input. Through these proposals, the community care business will be able to complete and have future value as a universal aged care system.

A Study on Improvement through Analysis of Problem on Physical Activity Promotion System(PAPS) (학생건강체력시스템(PAPS)의 문제점 분석과 개선방안에 대한 연구)

  • Park, Hyoung-Kil
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.7
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    • pp.87-96
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    • 2021
  • The purpose of this study is to analyze the problems of the Physical Activity Promotion System(PAPS) implemented in elementary, middle, and high schools in Korea and to prepare improvement measures. The data of the study was obtained through in-depth interviews, related papers, and press releases. The research participants of this study were 5 incumbent physical education teachers who directly instruct and measure PAPS at school and 5 college students who directly experienced PAPS. The results of the study are as follows. First, the problems that occurred in the educational environment of PAPS were students' indifference, teachers' passive guidance, and decreased physical education hours replaced by PAPS measurement days. Second, the problems occurring in the measurement environment of PAPS were errors due to measurement equipment, deviations due to different measurement locations, and differences in grades according to measurement items. Third, the problems that occur in the measurement process of PAPS are the lack of measurement personnel, the expedient physical fitness measurement, and the non-standardized measurement method. In order to improve these problems and successfully apply PAPS, the following improvement measures should be attempted. Details on this are as follows. First, teachers should inspire students' interest and interest in PAPS. Second, it is necessary to secure the reliability of the measurement result value of PAPS. Third, it is necessary to systematically supplement the school education system for PAPS measurement.

A Study on the Spatial Therapy Program through the Analysis of the Meaning and Value of Old Houses : Focus on Kwon Seong-baek Old House in Andong (고택의 의미와 가치 분석을 통한 공간치료 프로그램 연구 : 안동 권성백 고택을 중심으로)

  • Jo, Jeong-Eun;Jang, Chang-Su;Kwon, Ki-Chang
    • 지역과문화
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    • v.7 no.4
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    • pp.49-68
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    • 2020
  • The study of complementary medicine for the mental illness of modern people has been made up of academic fields. Psychotherapy, art therapy, literary therapy and dance therapy are among them, but these non-integrated studies are extremely limited to apply to reality. Collaboration with the medical community seeking supplementary measures after drug treatment is also a problem, and it is even more difficult to institutionalize them in a policy way. In response, the study suggested a shift to a space-oriented treatment paradigm by studying the value of space that most treatment programs value. Based on the theory of integrated literature therapy developed in Germany and introduced into Korea, the Tetra system was applied to one of Korea's cultural heritages. And I presented a sample of how to program the characteristics of the old house space. Kwon Seong-baek old house in Andong was considered a representative space and analyzed. As a similar case, we looked at the Healian Sun Village, the Knife Village in Germany, and the Temple Stay of Bongeunsa Temple to find out the actual conditions of space utilization. Accordingly, space treatment programs such as walking, writing poems, reading poems, and writing letters were presented by analyzing old houses with a Tetra system. This is significant as the first study to incorporate spatialization and placeability into the program.

Multi-fidelity uncertainty quantification of high Reynolds number turbulent flow around a rectangular 5:1 Cylinder

  • Sakuma, Mayu;Pepper, Nick;Warnakulasuriya, Suneth;Montomoli, Francesco;Wuch-ner, Roland;Bletzinger, Kai-Uwe
    • Wind and Structures
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    • v.34 no.1
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    • pp.127-136
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    • 2022
  • In this work a multi-fidelity non-intrusive polynomial chaos (MF-NIPC) has been applied to a structural wind engineering problem in architectural design for the first time. In architectural design it is important to design structures that are safe in a range of wind directions and speeds. For this reason, the computational models used to design buildings and bridges must account for the uncertainties associated with the interaction between the structure and wind. In order to use the numerical simulations for the design, the numerical models must be validated by experi-mental data, and uncertainties contained in the experiments should also be taken into account. Uncertainty Quantifi-cation has been increasingly used for CFD simulations to consider such uncertainties. Typically, CFD simulations are computationally expensive, motivating the increased interest in multi-fidelity methods due to their ability to lev-erage limited data sets of high-fidelity data with evaluations of more computationally inexpensive models. Previous-ly, the multi-fidelity framework has been applied to CFD simulations for the purposes of optimization, rather than for the statistical assessment of candidate design. In this paper MF-NIPC method is applied to flow around a rectan-gular 5:1 cylinder, which has been thoroughly investigated for architectural design. The purpose of UQ is validation of numerical simulation results with experimental data, therefore the radius of curvature of the rectangular cylinder corners and the angle of attack are considered to be random variables, which are known to contain uncertainties when wind tunnel tests are carried out. Computational Fluid Dynamics (CFD) simulations are solved by a solver that employs the Finite Element Method (FEM) for two turbulence modeling approaches of the incompressible Navier-Stokes equations: Unsteady Reynolds Averaged Navier Stokes (URANS) and the Large Eddy simulation (LES). The results of the uncertainty analysis with CFD are compared to experimental data in terms of time-averaged pressure coefficients and bulk parameters. In addition, the accuracy and efficiency of the multi-fidelity framework is demonstrated through a comparison with the results of the high-fidelity model.

A Study on Calculation of Urban Compactness Index Considering Space Syntax: Focusing on the Declining Local Cities (공간구문론을 활용한 도시 압축지수 산정에 관한 연구: 소멸위험도시를 중심으로)

  • HA, Ji-Hye;KANG, Jung-Eun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.3
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    • pp.29-58
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    • 2022
  • Recently, Korea has been experiencing a problem of population decline, therefore the transition to a compact spatial structure is being urged. However, what is required is not just physical compression, but a compact city that also considers connectivity, in view of the changes in today's demographic and industrial structure. From this point of view, this study measures the compressibility of domestic cities suffering from extinction risk due to low birth rates, aging population, and population decline, and examined the spatial structure characteristics. In addition to the compressibility evaluation index used in previous studies, the compressibility of six indicators (population, land use, service accessibility, transport accessibility, connectivity, and concentration) was compared and analyzed, and a comprehensive compression index was calculated. The analysis results, based on the comprehensive compression index, classified 2.3% cities in the first grade, 4.6% in the second grade, 16.09% in the third grade, 43.68% in the fourth grade, and 33.33% in the fifth grade areas. Currently, the urban characteristics affecting the compactness index differ from region to region. Therefore, it is necessary to establish measures and policies for extinction risk considering the influence of each region's compactness index. This study is meaningful in that connectivity was considered using spatial syntax, and the compactness of cities at risk of extinction was compared and analyzed quantitatively. It is expected that this study will be used as basic data to establish the direction and action strategy for extinction risk cities.

Cyber attack group classification based on MITRE ATT&CK model (MITRE ATT&CK 모델을 이용한 사이버 공격 그룹 분류)

  • Choi, Chang-hee;Shin, Chan-ho;Shin, Sung-uk
    • Journal of Internet Computing and Services
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    • v.23 no.6
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    • pp.1-13
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    • 2022
  • As the information and communication environment develops, the environment of military facilities is also development remarkably. In proportion to this, cyber threats are also increasing, and in particular, APT attacks, which are difficult to prevent with existing signature-based cyber defense systems, are frequently targeting military and national infrastructure. It is important to identify attack groups for appropriate response, but it is very difficult to identify them due to the nature of cyber attacks conducted in secret using methods such as anti-forensics. In the past, after an attack was detected, a security expert had to perform high-level analysis for a long time based on the large amount of evidence collected to get a clue about the attack group. To solve this problem, in this paper, we proposed an automation technique that can classify an attack group within a short time after detection. In case of APT attacks, compared to general cyber attacks, the number of attacks is small, there is not much known data, and it is designed to bypass signature-based cyber defense techniques. As an attack model, we used MITRE ATT&CK® which modeled many parts of cyber attacks. We design an impact score considering the versatility of the attack techniques and proposed a group similarity score based on this. Experimental results show that the proposed method classified the attack group with a 72.62% probability based on Top-5 accuracy.

Development of an Intelligent Illegal Gambling Site Detection Model Based on Tag2Vec (Tag2vec 기반의 지능형 불법 도박 사이트 탐지 모형 개발)

  • Song, ChanWoo;Ahn, Hyunchul
    • Journal of Intelligence and Information Systems
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    • v.28 no.4
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    • pp.211-227
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    • 2022
  • Illegal gambling through online gambling sites has become a significant social problem. The development of Internet technology and the spread of smartphones have led to the proliferation of illegal gambling sites, so now illegal online gambling has become accessible to anyone. In order to mitigate its negative effect, the Korean government is trying to detect illegal gambling sites by using self-monitoring agents or reporting systems such as 'Nuricops.' However, it is difficult to detect all illegal sites due to limitations such as a lack of staffing. Accordingly, several scholars have proposed intelligent illegal gambling site detection techniques. Xu et al. (2019) found that fake or illegal websites generally have unique features in the HTML tag structure. It implies that the HTML tag structure can be important for detecting illegal sites. However, prior studies to improve the model's performance by utilizing the HTML tag structure in the illegal site detection model are rare. Against this background, our study aimed to improve the model's performance by utilizing the HTML tag structure and proposes Tag2Vec, a modified version of Doc2Vec, as a methodology to vectorize the HTML tag structure properly. To validate the proposed model, we perform the empirical analysis using a data set consisting of the list of harmful sites from 'The Cheat' and normal sites through Google search. As a result, it was confirmed that the Tag2Vec-based detection model proposed in this study showed better classification accuracy, recall, and F1_Score than the URL-based detection model-a comparative model. The proposed model of this study is expected to be effectively utilized to improve the health of our society through intelligent technology.

A Study on Mechanical Properties and Applicability of CNT-Mixed Grout (CNT-Mixed grout의 역학적 특성 및 적용성 연구)

  • Kim, Seunghyun;Kim, Kanghyun;Shin, Jongho
    • Journal of the Korean GEO-environmental Society
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    • v.23 no.9
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    • pp.5-16
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    • 2022
  • In recent years due to the development of urban and underground space, the number of ground disasters is increasing, and it is also leading to social problems. To solve the problem, a grouting method is generally used. However, the grouting method has material (grout) limitations in permeability, gelation properties and tensile resistance. Therefore, research on grout materials mixed with fibers is actively carried out to improve the problems. However, in the actual ground injection process, many difficulties have been faced causing the blockage of the inlet port and the injection tube. In this study, 'CNT-mixed grout material' was developed using CNT powder that can reinforce the tensile strength of soils. The uniaxial compressive and tensile strength tests were performed to obtain the optimal content and mechanical properties of the CNT Powder-mixed grout. It was found that the optimal CNT powder content is 0.5% that gives the average maximum strength. A one-dimensional injection test and the bulb formation test were carried out, and it was identified that the injection rate and bulb form could be controlled by pressure and mixing ratio. Field application of the CNT-Mixed grout is simulated using numerical analysis of slopes, foundations, and tunnels reinforced in several types. The positive effect of reducing plastic ranges and settlements was confirmed.

Comparative Study of Anomaly Detection Accuracy of Intrusion Detection Systems Based on Various Data Preprocessing Techniques (다양한 데이터 전처리 기법 기반 침입탐지 시스템의 이상탐지 정확도 비교 연구)

  • Park, Kyungseon;Kim, Kangseok
    • KIPS Transactions on Software and Data Engineering
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    • v.10 no.11
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    • pp.449-456
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    • 2021
  • An intrusion detection system is a technology that detects abnormal behaviors that violate security, and detects abnormal operations and prevents system attacks. Existing intrusion detection systems have been designed using statistical analysis or anomaly detection techniques for traffic patterns, but modern systems generate a variety of traffic different from existing systems due to rapidly growing technologies, so the existing methods have limitations. In order to overcome this limitation, study on intrusion detection methods applying various machine learning techniques is being actively conducted. In this study, a comparative study was conducted on data preprocessing techniques that can improve the accuracy of anomaly detection using NGIDS-DS (Next Generation IDS Database) generated by simulation equipment for traffic in various network environments. Padding and sliding window were used as data preprocessing, and an oversampling technique with Adversarial Auto-Encoder (AAE) was applied to solve the problem of imbalance between the normal data rate and the abnormal data rate. In addition, the performance improvement of detection accuracy was confirmed by using Skip-gram among the Word2Vec techniques that can extract feature vectors of preprocessed sequence data. PCA-SVM and GRU were used as models for comparative experiments, and the experimental results showed better performance when sliding window, skip-gram, AAE, and GRU were applied.