• Title/Summary/Keyword: connected control method

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Large-scale Virtual Power Plant Management Method Considering Variable and Sensitive Loads (가변 및 민감성 부하를 고려한 대단위 가상 발전소 운영 방법)

  • Park, Yong Kuk;Lee, Min Goo;Jung, Kyung Kwon;Lee, Yong-Gu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.5
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    • pp.225-234
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    • 2015
  • Nowadays a Virtual Power Plant (VPP) represents an aggregation of distributed energy resource such as Distributed Generation (DG), Combined Heat and Power generation (CHP), Energy Storage Systems (ESS) and load in order to operate as a single power plant by using Information and Communication Technologies, ICT. The VPP has been developed and verified based on a single virtual plant platform which is connected with a number of various distributed energy resources. As the VPP's distributed energy resources increase, so does the number of data from distributed energy. Moreover, it is obviously inefficient in the aspects of technique and cost that a virtual plant platform operates in a centralized manner over widespread region. In this paper the concept of the large-scale VPP which can reduce a error probability of system's load and increase the robustness of data exchange among distributed energy resources will be proposed. In addition, it can directly control and supervise energy resource by making small size's virtual platform which can make a optimal resource scheduling to consider of variable and sensitive load in the large-scale VPP. It makes certain the result is verified by simulation.

A Study on 2D Pattern Design Module and 3D Cloth Simulation System based on Octree Space Subdivision Method (2차원 패턴 디자인 모듈과 Octree 공간 분할 방법을 이용한 3차원 의복 시뮬레이션 시스템에 관한 연구)

  • Kim, Ju-Ri;Joung, Suck-Tae;Jung, Sung-Tae
    • Journal of Korea Multimedia Society
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    • v.10 no.4
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    • pp.527-536
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    • 2007
  • This paper proposes a 3D fashion design system that generates a 3D clothes model by using 2D patterns of clothes and drapes the 3D clothes model on a 3D human model. In the proposed system, 2D patterns of clothes are designed by selecting comer points of 2D mesh. After designing 2D patterns, a 3D clothes model is designed by describing the control points to be connected between 2D patterns. The proposed system reads a 3D human body model file and the designed 3D clothes model and creates a 3D human model putting on the clothes by using the mass-spring model based physical simulation. It calculates collision and reaction between the triangles of human body model and those of clothes for realistic simulation. Because the number of triangles is very large, the collision and reaction processing need a lot of time. To solve this problem, the proposed system decreases the number of collision and reaction processing by using the Octree space subdivision technique. It took a few seconds for generating a 3D human model putting on the designed 3D clothes.

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Evaluation of Source Identification Method Based on Energy-Weighting Level with Portal Monitoring System Using Plastic Scintillator

  • Lee, Hyun Cheol;Koo, Bon Tack;Choi, Chang Il;Park, Chang Su;Kwon, Jeongwan;Kim, Hong-Suk;Chung, Heejun;Min, Chul Hee
    • Journal of Radiation Protection and Research
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    • v.45 no.3
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    • pp.117-129
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    • 2020
  • Background: Radiation portal monitors (RPMs) involving plastic scintillators installed at the border inspection sites can detect illicit trafficking of radioactive sources in cargo containers within seconds. However, RPMs may generate false alarms because of the naturally occurring radioactive materials. To manage these false alarms, we previously suggested an energy-weighted algorithm that emphasizes the Compton-edge area as an outstanding peak. This study intends to evaluate the identification of radioactive sources using an improved energy-weighted algorithm. Materials and Methods: The algorithm was modified by increasing the energy weighting factor, and different peak combinations of the energy-weighted spectra were tested for source identification. A commercialized RPM system was used to measure the energy-weighted spectra. The RPM comprised two large plastic scintillators with dimensions of 174 × 29 × 7 ㎤ facing each other at a distance of 4.6 m. In addition, the in-house-fabricated signal processing boards were connected to collect the signal converted into a spectrum. Further, the spectra from eight radioactive sources, including special nuclear materials (SNMs), which were set in motion using a linear motion system (LMS) and a cargo truck, were estimated to identify the source identification rate. Results and Discussion: Each energy-weighted spectrum exhibited a specific peak location, although high statistical fluctuation errors could be observed in the spectrum with the increasing source speed. In particular, 137Cs and 60Co in motion were identified completely (100%) at speeds of 5 and 10 km/hr. Further, SNMs, which trigger the RPM alarm, were identified approximately 80% of the time at both the aforementioned speeds. Conclusion: Using the modified energy-weighted algorithm, several characteristics of the energy weighted spectra could be observed when the used sources were in motion and when the geometric efficiency was low. In particular, the discrimination between 60Co and 40K, which triggers false alarms at the primary inspection sites, can be improved using the proposed algorithm.

A 65-nm CMOS Low-Power Baseband Circuit with 7-Channel Cutoff Frequency and 40-dB Gain Range for LTE-Advanced SAW-Less RF Transmitters (LTE-Advanced SAW-Less 송신기용 7개 채널 차단 주파수 및 40-dB 이득범위를 제공하는 65-nm CMOS 저전력 기저대역회로 설계에 관한 연구)

  • Kim, Sung-Hwan;Kim, Chang-Wan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.3
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    • pp.678-684
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    • 2013
  • This paper describes a low-power baseband circuit for SAW-less LTE-Advanced transmitters. The proposed transmitter baseband circuit consists of a 2nd-order Tow-Thomas type active RC-LPF and a 1st-order passive RC LPF. It can provide a 7 multi-channel cut-off frequencies and wide gain control range of -41 dB ~ 0 dB with a 1-dB step. The proposed 2nd-order active RC-LPF adopts an op-amp in which three other sub-op amps are in parallel connected to reduce DC current for different cutoff frequency. In addition, each sub-op amp adopts both Miller and feed-forward phase compensation method to achieve an UGBW of more than 1-GHz with a small DC power consumption. The proposed baseband circuit is implemented in 65-nm CMOS technology, consuming DC power from 6.3 mW to 24.1 mW from a 1.2V supply voltage for each different cut-off frequency.

Research on Continuous After-Treatment Process and System for DTP(Digital Textile Printing) (DTP(Digital Textile Printing)용 후처리 및 연속공정 시스템에 관한 연구)

  • Park, Soon-Young;Jeon, Dong-Won;Park, Yoon-Cheol;Lee, Beom-Soo;Cho, Hang-Sung
    • Journal of Fashion Business
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    • v.15 no.5
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    • pp.43-54
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    • 2011
  • Digital Textile Printing(DTP) is appropriate for quick response system(QRS) and is closely connected with high value added fashion industry. Fashion products of high price are mainly silk and cotton. For high quality DTP products, it is important to optimize the parameters of media, pre and after-treatment, ink, printer, etc. DTP for these two fiber materials is also accompanied certainly with steaming as after-treatment process for coloration. Role of steam is like water in exhaustion dyeing. Steam can diffuse dye or ink in printing paste to fiber. Quality of DTP products depend on after-treatment processes such as steaming, washing, drying. Current production amount of DTP is smaller than one of conventional textile printing. However conventional after-treatment system has been using so far. This is mismatched with DTP in terms of process efficiency, spot work of small lot, quality control. In this study, continuous after-treatment system has been suitably designed for DTP that washing and drying are available after steaming. So, It is possible to improve efficiency of DTP process. Especially, the effects of after-treatment process, such as temperature of heat drum, steaming time on printability, color difference, color fastness were examined. Two types of samples(cotton knit and silk fabrics) were used. The results were obtained as follows : First, there is no a wide difference between the K/S values of cotton and silk treated with continuous after-treatment system and those of sample treated with conventional printing after-treatment method. So it is more effective to use the continuous after-treatment system than conventional printing after-treatment system in case of the daily throughput of 1,000 yards below. Second, after continuous after-treatment for DTP, K/S values were increased and lightness($L^*$) values were decreased. ${\Delta}E$ values were below 2.3. Third, DTP samples treated with continuous after-treatment system were tested for fastness(washing, light, rubbing). Grades of fastness(washing, light, rubbing) were above 3 grade.

Metadata Management for E-Commerce Transactions in Digital Library (디지털 도서관에서 전자상거래 트랜잭션을 위한 메타데이타 관리 기법)

  • Choe, Il-Hwan;Park, Seog
    • Journal of KIISE:Databases
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    • v.29 no.1
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    • pp.34-43
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    • 2002
  • Since traditional static metadata set like Dublin Core has static metadata attributes about bibliography information, integration of metadata for various metadata, problems about standard and extension of metadata must be considered for applying it to new environment. Specially, as event-driven metadata write method included the notion of e-commerce come out for interoperability in digital libraries, traditional metadata management which cannot distinguish between different kinds of update operations to new extension of metadata set occurs unsuitable waiting of update operation. So, improvement is needed about it. In this paper, we show whether alleviative transaction consistency can be applied to digital library or not. Also it would divide newer metadata into static metadata attribute connected in read operation within user read-only transaction and dynamic metadata attribute in update operation within dynamic(e-commerce) update transactions. We propose newer metadata management algorithm considered in classfication of metadata attributes and dynamic update transaction. Using two version for minimal maintenance cost and ARU(Appended Refresh Unit) for dynamic update transaction, to minimize conflict between read and write operations shows fast response time and high recency ratio. As a result of the performance evaluation, we show our algorithm is proved to be better than other algorithms in newer metadata environments.

Theory and practice of the interlibrary loan service (상호대차(相互貸償) 제도의 이론(理論)과 응용)

  • Chun Myung Sook
    • Journal of the Korean Society for Library and Information Science
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    • v.13
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    • pp.39-71
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    • 1986
  • Interlibrary loan has been a very common library service in the developed countries but it is yet to be actualized formerly in Korea. As Korea is moving toward an information society where all the individual user's request in the library should be met, we need to understand, in detail, the theory and practice of interlibrary loan service. As various information technology has been applied to the libraries, the libraries became the open system. Thus, the libraries become more cooperative, form networks, and make interlibrary loan service available. This study is based on the following three hypothesis formulated from the systems theory. 1. If libraries cooperate each other and form some kind of networks by mail, computers or telecommunications, they become the open system. 2. If a library develops as the open system, interlibrary loan becomes available in the library. 3. If the interlibrary loan system works, the role of the librarians will be changed. The research was carried out by analyzing the various studies about interlibrary loan service and by examining the interlibrary loan systerns presently working in the U.S.. The conclusions are reached deductively from the data. Some of the terminology used are defined as follows: System: a network of interrelated procedures that are joined together to perform an activity or to accomplish a specific objective. It is, in effect, all the ingredient which make up the whole. Cooperation: Working together to benefit participant libraries. Network: a much more structured type of cooperation in which definite regions or areas are connected by electronic or other means to promote interlibrary loaning of materials, in-service traing & other sharing of resources. Interlibrary loan: the lending of books between libraries. The model of cooperation or networks was used to be (1) a star type, (2) a hieranchical type, (3) a distributed type or (4) the combination of aforementioned three. However, the development of the telecommunications and computers enables all kinds of libraires cooperate together. Interlibrary loan service starts with the needs of user's information. The information have to be logically accessed through bibliographies, computers, electronic mails and satellite communications. And the logical access requires the information technology and the libraries become cooperative. The physical access to the information follows next but only traditional method of mail and some commercial service are currently available for this purpose. Therefore, researches are needed to develop this physical access. If the libraries form networks, the microaspect of library changes accordingly as the macroaspect changes. If the libraries . cooperate to become one large world library, the librarians plan, organize, control library operations and report the results. And the librarians work inside and outside of the library to cooperate with other libraries. Only the cooperation of the libraries will enhance interlibrary loan and the Korean librarians have to be prepared to accept the new role of librarianship for the interlibrary loan service.

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Relationship between dairy products, fish and shellfish intake and metabolic syndrome risk factors in prediabetes: based on the sixth Korea National Health and Nutrition Examination Survey (KNHANES VI-3) 2015 (전당뇨병 대상자의 유제품 및 어패류 섭취와 대사증후군 위험인자와의 관련성 연구 : 2015년 제 6기 국민건강영양조사 자료를 바탕으로)

  • Park, Jeong Seop;Kim, Kyoung Yun
    • Journal of Nutrition and Health
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    • v.50 no.5
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    • pp.447-459
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    • 2017
  • Purpose: Metabolic Syndrome (MetS) is defined as a cluster of inter-connected metabolic disorders involving the glucose metabolism, dyslipidaemia, high blood pressure, and abdominal obesity. The worldwide prevalence has been rapidly increasing to approximately 20~25%, and the prevalence in Korea as of 2012 was reported to be 31.3%. The association of MetS with various diseases needs to be analyzed by conducting an investigation of frequently consumed foods, such as dairy products, fish, and shellfish in prediabetic subjects. Methods: The dietary intake of subjects who met the criteria of the study from January to December 2015 was assessed using the 24-hour recall method. After adjusting the age, sex, BMI, and total energy intake, which are confounding factors that may affect the dietary intake of the subjects, the associations of dairy products, fish, and shellfish intake with the MetS risk factors was analyzed. Results: In prediabetes, the intake of subjects who consumed more than the dairy products median (187.0 g) and the elevation risk of TC [OR, 2.369; 95% CI, 1.057 to 5.312] showed a significant positive association. In prediabetes, the intake of subjects who consumed more than the fish and shellfish median (44.0 g) and the elevation risk of BP showed a significantly weak negative association [OR, 0.073; 95% CI, 0.010 to 0.520]. The probability that the blood LDL cholesterol was ${\geq}100mg/dL$ decreased 0.397 times [95% CI, 0.189 to 0.832]. Conclusion: To control the metabolic risk factors of pre-diabetic and vascular disease subjects, proper dairy, fish and shellfish intake will be important.

A Study on the Space Composition for Department of Delivery in Regional Public Hospital (지역거점 공공병원의 분만부 공간구성에 관한 연구(1))

  • Park, Kyeong Hyeon;Shin, Hwa Kyoung;Chai, Choul Gyun
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.28 no.3
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    • pp.47-54
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    • 2022
  • Purpose: This study presents the analysis on space usage of delivery departments in regional public hospitals. The results intention is to achieve improvement of the delivery environment for the mothers and newborns regarding exposure prevention and efficient infection control. The purpose of this study is to provide fundamental data for architectural plans and guidelines for the delivery department. Method: The investigation and analysis were based on research papers, legal systems, public medical statistical data, and the architectural floor plan drawing. For research, 20 regional public hospitals with an operating delivery room were excluded. Regarding data accessibility, 15 regional public hospitals were selected. Results: To overcome the increased vulnerability of the delivery department, the research results of basic data is provided for the establishment to address urgent needs and rapid response. Thus, the research results are as follows: Firstly, the delivery department needs to respond promptly according to the type of patients. For example, in a case of emergency surgery, a connected circulation plan with the related departments is needed. Secondly, for the environment of the delivery area, alleviating anxiety is imperative for pregnant patients and guardians, labor, childbirth, and recovery. Therefore, these needs must be addressed for treatment space and circulation. Lastly, the delivery department is classified into three areas for analysis: access area, treatment area, and support area. In most of the delivery departments of the 15 selected hospitals, there is no space for the access and support area except for the labor and delivery rooms in the treatment area. For the access area, a waiting area, changing room for pregnant women and guardians, and a storage space for contaminated linens are required for infection prevention, safety, and efficiency. For the treatment area, childbirth processes and circulation should have space reserved for labor, delivery, recovery, examination, and treatment. In preparation for an emergency during childbirth, emergency response measures and supporting space needs to be established. For the support area, circulation and rooms are to be designed for medical staff support, activity space, storage and transportation of equipment, and urgent medical treatment. Implications: Along with the low fertility rate and the decrease of medical institutions that operate delivery departments, for the purpose of establishing a public medical service system and a healthy medical environment for mothers and newborns, the researched information demonstrates basic data on space plan of delivery departments in regional public hospitals.

A Study on the Calculation of Optimal Compensation Capacity of Reactive Power for Grid Connection of Offshore Wind Farms (해상풍력단지 전력계통 연계를 위한 무효전력 최적 보상용량 계산에 관한 연구)

  • Seong-Min Han;Joo-Hyuk Park;Chang-Hyun Hwang;Chae-Joo Moon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.1
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    • pp.65-76
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    • 2024
  • With the recent activation of the offshore wind power industry, there has been a development of power plants with a scale exceeding 400MW, comparable to traditional thermal power plants. Renewable energy, characterized by intermittency depending on the energy source, is a prominent feature of modern renewable power generation facilities, which are structured based on controllable inverter technology. As the integration of renewable energy sources into the grid expands, the grid codes for power system connection are progressively becoming more defined, leading to active discussions and evaluations in this area. In this paper, we propose a method for selecting optimal reactive power compensation capacity when multiple offshore wind farms are integrated and connected through a shared interconnection facility to comply with grid codes. Based on the requirements of the grid code, we analyze the reactive power compensation and excessive stability of the 400MW wind power generation site under development in the southwest sea of Jeonbuk. This analysis involves constructing a generation site database using PSS/E (Power System Simulation for Engineering), incorporating turbine layouts and cable data. The study calculates reactive power due to charging current in internal and external network cables and determines the reactive power compensation capacity at the interconnection point. Additionally, static and dynamic stability assessments are conducted by integrating with the power system database.