• Title/Summary/Keyword: Power system operation

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A Study of Wind Characteristics around Nuclear Power Plants Based on the Joint Distribution of the Wind Direction and Wind Speed

  • Yunjong Lee
    • Journal of Radiation Industry
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    • v.17 no.3
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    • pp.299-307
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    • 2023
  • Given that toxic substances are diffused by the various movements of the atmosphere, it is very important to evaluate the risks associated with this phenomenon. When analyzing the behavioral characteristics of these atmospheric diffusion models, the main input data are the wind speed and wind direction among the meteorological data. In particular, it is known that a certain wind direction occurs in summer and winter in Korea under the influence of westerlies and monsoons. In this study, synoptic meteorological observation data provided by the Korea Meteorological Administration were analyzed from January 1, 2012 to the end of August of 2022 to understand the regional wind characteristics of nuclear power plants and surrounding areas. The selected target areas consisted of 16 weather stations around the Hanbit, Kori, Wolsong, Hanul, and Saeul nuclear power plants that are currently in operation. The analysis was based on the temperature, wind direction, and wind speed data at those locations. Average, maximum, minimum, median, and mode values were analyzed using long-term annual temperature, wind speed, and wind direction data. Correlation coefficient values were also analyzed to determine the linear relationships among the temperature, wind direction, and wind speed. Among the 16 districts, Uljin had the highest wind speed. The median wind speed values for each region were lower than the average wind speed values. For regions where the average wind speed exceeds the median wind speed, Yeongju, Gochang, Gyeongju, Yeonggwang, and Gimhae were calculated as 0.69 m s-1, 0.54m s-1, 0.45m s-1, 0.4m s-1, and 0.36m s-1, respectively. The average temperature in the 16 regions was 13.52 degrees Celsius; the median temperature was 14.31 degrees and the mode temperature was 20.69 degrees. The average regional temperature standard deviation was calculated and found to be 9.83 degrees. The maximum summer temperatures were 39.7, 39.5, and 39.3 in Yeongdeok, Pohang, and Yeongcheon, respectively. The wind directions and speeds in the 16 regions were plotted as a wind rose graph, and the characteristics of the wind direction and speed of each region were investigated. It was found that there is a dominant wind direction correlated with the topographical characteristics in each region. However, the linear relationship between the wind speed and direction by region varied from 0.53 to 0.07. Through this study, by evaluating meteorological observation data on a long-term synoptic scale of ten years, regional characteristics were found.

Optical Diagnostics of Nanopowder Processed in Liquid Plasmas

  • Bratescu, M.A.;Saito, N.;Takai, O.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.17-18
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    • 2011
  • Plasma in liquid phase has attracted great attention in the last few years by the wide domain of applications in material processing, decomposition of organic and inorganic chemical compounds and sterilization of water. The plasma in liquid is characterized by three main regions which interact each - other during the plasma operation: the liquid phase, which supply the plasma gas phase with various chemical compounds and ions, the plasma in the gas phase at atmospheric pressure and the interface between these two regions. The most complex region, but extremely interesting from the fundamental, chemical and physical processes which occur here, is the boundary between the liquid phase and the plasma gas phase. In our laboratory, plasma in liquid which behaves as a glow discharge type, is generated by using a bipolar pulsed power supply, with variable pulse width, in the range of 0.5~10 ${\mu}s$ and 10 to 30 kHz repetition rate. Plasma in water and other different solutions was characterized by electrical and optical measurements. Strong emissions of OH and H radicals dominate the optical spectra. Generally water with 500 ${\mu}S/cm$ conductivity has a breakdown voltage around 2 kV, depending on the pulse width and the repetition rate of the power supply. The characteristics of the plasma initiated in ultrapure water between pairs of different materials used for electrodes (W and Ta) were investigated by the time-resolved optical emission and the broad-band absorption spectroscopy. The deexcitation processes of the reactive species formed in the water plasma depend on the electrode material, but have been independent on the polarity of the applied voltage pulses. Recently, Coherent anti-Stokes Raman Spectroscopy method was employed to investigate the chemistry in the liquid phase and at the interface between the gas and the liquid phases of the solution plasma system. The use of the solution plasma allows rapid fabrication of the metal nanoparticles without being necessary the addition of different reducing agents, because plasma in the liquid phase provides a reaction field with a highly excited energy radicals. We successfully synthesized gold nanoparticles using a glow discharge in aqueous solution. Nanoparticles with an average size of less than 10 nm were obtained using chlorauric acid solutions as the metal source. Carbon/Pt hybrid nanostructures have been obtained by treating carbon balls, synthesized in a CVD chamber, with hexachloro- platinum acid in a solution plasma system. The solution plasma was successfully used to remove the template remained after the mesoporous silica synthesis. Surface functionalization of the carbon structures and the silica surface with different chemical groups and nanoparticles, was also performed by processing these materials in the liquid plasma.

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Development of Korean Warrior Platform Architecture (한국형 워리어플랫폼 아키텍처 개발 연구)

  • Kim, Wukki;Shin, Kyuyong;Cho, Seongsik;Baek, Seungho;Kim, Yongchul
    • Journal of Convergence for Information Technology
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    • v.11 no.5
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    • pp.111-117
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    • 2021
  • With the rapid development of advanced science and technology including the 4th industrial revolution, the future battlefield environment is evolving at a rapid pace. In order to actively respond to issues such as reduction of military resources and shortening of service period, and to emphasize the realization of human-centered values, the Ministry of National Defense is re-establishing the role of the Army in accordance with the defense reform and is promoting the Warrior Platform, a next-generation individual combat system. In this paper, we intend to present the optimal warrior platform architecture suitable for the Korean Army by realizing the concept of future ground operations and analyzing overseas cases. We analyze the essential abilities required of individual combatants and the abilities required for each unit type, and specifically presents a plan for integration and linkage of warrior platform equipment. We also propose an efficient business promotion direction by presenting the data flow and power connection diagram between the devices that need integration and interworking.

Preliminary Design of the Forced Gas Drying System for Spent Nuclear Fuel Dry Storage (사용후핵연료 건식저장을 위한 기체강제순환 건조장치 예비설계)

  • Chae, Gyung-sun;Shin, Kyung-wook;Park, Byeong-mok;Han, Jae-hyun;Lee, Geon-hui;Park, Jae-seok
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.4
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    • pp.403-409
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    • 2017
  • For dry storage of the spent nuclear fuel (SNF) stored in the storage pool of a nuclear power plant, essentially all moisture must be removed to prevent corrosion of the assembly and canister internals and/or degradation of fuel cladding integrity after SNF canister loading operation. R&D work is now in progress on a forced gas drying system that can be used to remove residual water in canisters. In this work, preliminary design is performed to manufacture the forced gas drying system. This process includes a case study of dry methods for canister moisture removal, relative codes and standards, confirmation of adequate dryness, needs analysis at plant sites, and characteristics of SNF stored in pools. Through this preliminary design work, we obtained a conceptual flow diagram and preliminary P&ID of the forced gas drying system. The results of this study can be used to determine details of the design to manufacture the forced gas drying system.

Mixing Zone Analysis on Outfall Plume considering Influence of Temperature Variation (수온 변화의 영향을 고려한 방류관 플룸의 혼합역 분석)

  • Kim Ji-Yeon;Lee Joong-Woo
    • Journal of Navigation and Port Research
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    • v.28 no.10 s.96
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    • pp.947-953
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    • 2004
  • As a large scale port development in coastal waters proceeds step by step and populations in the vicinity of port are getting increased, the issue on 'how to dispose the treated municipal water and wastewater in harbor' brings peoples' concern. The submarine outfall system discharges the primary or secondary treated effluent at the coastline or in deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding sea water and becomes very dilute. We intended in this paper to investigate the impact on dilution of effluent and the behavior of flume under the conditions of the seasonal and spatial temperature variations, which have not been noticeable in designing effective marine outfall system. To predict and analyze the behaviour and dilution characteristics of plume not just with the effluent temperature, but also with the seasonal variation of temperature of surround water, CORMIX( Cornell Mixing Zone Expert System)-GI have been applied. The results should be used with caution in evaluation the mixing zone characteristics of discharged water. We hope to help for the effective operation of outfall system, probable outfall design, protection of water quality, and warm water discharges from a power plant, etc.

Development of Safety Management Information System for Gas Industries Using Database (데이터베이스를 이용한 가스산업시설의 안전관리정보시스템 구축)

  • Um Sung-In;Kim Sung-Bin;Kim Yun-Hwa;Baek Jong-Bae;Kim In-Won;Ko Jae-Wook
    • Journal of the Korean Institute of Gas
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    • v.2 no.2
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    • pp.48-54
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    • 1998
  • In this study a computerized prototype system was developed with Safety Management Information System(SMIS version 1.0) as a main system and database as subsystems to handle information. Safety management information consists of management aspects and technical elements, but SMIS consists of 4 modules of technical elements to interrelate safety technologies closely. SMIS enables gas industries to manage process safety information effectively and to evaluate hazards. The results from SMIS can be used to the operation manual and the emergency plan. Data base consists of 3 modules of accident data, material data, and equipment data to support SMIS. Also, the case study results proved the usefulness of SMIS for searching and accumulating process safety data. Especially, MIS which has the database suggests a formal structure for scattered raw safety data in gas industries and brings reduction of man power and time.

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A Study on Detection Algorithm of Open Phase Fault in Grid-Connected Transformer for PV System (태양광전원 연계용변압기의 결상사고 검출 알고리즘에 관한 연구)

  • Kang, Kab-Seok;Tae, Dong-Hyun;Lee, Hu-Dong;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.22-33
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    • 2021
  • In the case of open phase faults caused by the disconnection of distribution feeders interconnected to a PV system, many problems can occur depending on the core type and wiring method of the grid-connected transformers. Moreover, open phase faults are difficult to detect because the open phase voltage of the existing protection relay (Open Phase Relay (47)) can be maintained, even though a disconnection fault occurred, depending on the wiring method and the iron core type of the grid-connected transformer for a PV system. Therefore, this paper proposes a novel algorithm to detect open phase faults by comparing the currents and phases between the primary and secondary sides of a grid-connected transformer. In addition, this paper presents the modeling of a distribution system and protection devices for detecting open phase faults using PSCAD/EMTDC S/W, and implements a test protection device for detecting open phase faults based on the above-mentioned modeling. The simulation and test results confirmed that the proposed algorithm is useful for detecting open phase faults according to the wiring method and iron core type of grid-connected transformer for a PV system because operation slope and unbalance rate of the primary current exceed the setting value (30[%]) of the protection device.

A Study on the Problems and Improvement of the Safety Management Law of Nuclear Facilities -Focused on Safety Management of Aquatic Products- (원자력시설 안전관리 법제의 문제점과 개선방안 연구 -수산물의 안전관리를 중심으로-)

  • Lee, Woo-Do
    • The Journal of Fisheries Business Administration
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    • v.50 no.2
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    • pp.23-40
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    • 2019
  • The main purpose of this study is to analyze and examine the problems of the law systems of the safety and maintenance of nuclear facilities and to propose the improvements with respect to the related problems especialy focused on safety management of aquatic products. Therefore, the results of the paper would be helpful to build an effective management law system of safety and maintenance of nuclear facilities and fisheries products. The research methods are longitudinal and horizontal studies. This study compares domestic policies with foreign policies of nuclear plants and aquatic products. Using the above methods, examining the current system of nuclear-related laws and regulations, we have found that there exist 13 Acts including "Nuclear Safety Act", etc. Safety laws related on nuclear facilities have seven Acts including "Nuclear Safety Act", "the Act on Physical Protection and Radiological Emergency", "Radioactive waste control Act", "Act on Protective Action Guidelines against Radiation in the Natural Environment", "Special Act on Assistance to the locations of facilities for disposal low and intermediate level radioactive waste", "Korea Institute of Nuclear Safety Act". "Act on Establishment and Operation of the Nuclear Safety and Security Commission". The seven laws are composed of 119 legislations. They have 112 lower statute of eight Presidential Decrees, six Primeministrial Decrees and Ministrial Decrees, 92 administrative rules (orders), 6 legislations of local self-government aself-governing body. The concluded proposals of this paper are as follows. Firstly, we propose that the relationship between the special law and general law should be re-established. Secondly, the terms with respect to law system of safety and maintenance of nuclear plants should be redefined and specified. Thirdly, it is advisable to re-examine and re-establish the Law System for Safety and Maintenance of Nuclear Facilities. and environmental rights like the French Nuclear Safety Legislation. Lastly, inadequate legislation on the aquatic pollution damage should be re-established. It is necessary to ensure sufficient transparency as well as environmental considerations in the policy decisions of the Korean government and legislation of the National Assembly. It is necessary to further study the possibilities of accepting the implications of the French legal system as a legal system in Korea. In conclusion, the safety management of nuclear facilities is not only focused on the secondary industry and the tertiary industry centering on power generation and supply, but also on the primary industry, which is the food of the people. It is necessary to prevent damage to be foreseen. Therefore, it is judged that there should be no harm to the people caused by contaminated marine products even if the "Food Safety Law for Prevention of Radiation Pollution Damage" is enacted.

Some Thoughts on Reestablishing Appraisal System of Presidential Records (대통령기록물 평가제도 재정립을 위한 몇 가지 단상)

  • Kim, Myoung-hun;Lee, Seung-il
    • The Korean Journal of Archival Studies
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    • no.79
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    • pp.271-303
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    • 2024
  • In our country, which has a strong presidential system, the power and responsibilities of the president are truly enormous. He is the head of state and diplomatic representative, and at the same time exercises authority over all areas of the country, including the legislature, judiciary, and constitutional institutions, along with his responsibilities as head of the executive branch. Considering these aspects, it can be said that presidential records created during the president's rule have a high level of national and historical significance and value compared to other public records. Considering these importance of presidential records, the Presidential Records Management Act was enacted in 2007 to establish an institutional mechanism to systematically manage presidential records. However, the current institutional basis for appraisal of presidential records is very weak. In this regard, there is a need to begin discussions on the appraisal of presidential records in earnest. Considering the national importance and symbolism of presidential records, it is necessary to establish a new direction for appraisal of presidential records that is different from general public records. Accordingly, in this paper, as part of reestablishing Korea's presidential records appraisal system, this article analyzed the status and problems of the current presidential records appraisal system and presented directions needed to find future improvement measures. To this end, as a premise for discussing the importance and value of presidential records, it examined the powers and responsibilities of the presidency as defined in our country's Constitution.Next, we looked at the appraisal system and method for presidential records that are currently in operation, and then analyzed the problems that emerged here in connection with the characteristics of presidential records. Based on this, it presented five perspectives on issues that need to be discussed publicly in the records management community in order to reestablish Korea's presidential records appraisal system in the future.

A Study in an Effective Programs for Emergency Care Delivery System (응급의료 전달체계의 충실 방안)

  • Kwon Sook Hee
    • Journal of Korean Public Health Nursing
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    • v.9 no.1
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    • pp.83-102
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    • 1995
  • As the society is being industrialized, the fast-paced economic development that has caused substantial increase in cerebrovascular and coronary artery diseases and the industrial development and increased use of means of transportation have resulted in the rapid rise of incidents in external injuries as well. So the pubic has become acutely aware of the need for fast and effective emergency care delivery system. The goal of emergency care delivery system is to meet the emergency care needs of patients. The emergency care delivery system is seeking to efficiently satisfy the care needs of people. Therefore the purpose of this study is designed to develop an effective programs for emergency care delivery system in Korea. The following specific objectives were investigated. This emergency care delivery system must have the necessary man power, for transfering the patients, communication net work, and emergency care facilities. 1) Man power Emergency care requires n0t only specialized traning in the emergency treatment but also knowledge and experience i11 other related area, so emergency care personnel traning program should be designed in order to adapt to the specific need of emergency patients. It will be necessary to ensure professional personnel who aquires the sufficient traning and experience for emergency care and to look for legal basis. We have to develop re-educational programs for emergency nurse specialist. They should be received speciality of emergency nursing care so that they will work actively and positively in emergency part. Emergency medical doctor and nurse specialist should be given an education which is related in emergency and critical care. Emergency care personnel will continue to provide both acute and continuing care as partner with other medical team. 2) Transfering the patients. Successful management of pre-hospital care requires adequate traning for the emergency medical technician. Traning program should be required to participate in a actual first aids activites in order to have apportunities to acquire practical skills as well as theoretical knowledge. The system of emergency medical technician should be remarkablly successful with first responder firefighters. Establishing this system must add necessary ambulances operating at any given time. It will be necessary to standardize the ambulance size and equipment. Ambulance should be arranged with each and every fire station. 3) Communication net work. The head office of emergency commumication network should be arranged with the head office of fire station in community. It is proposed that Hot-line system for emergency care should be introduce. High controlled ambulance and thirtial emergency center should simultaneously equip critical-line in order to communication with each other. Ordinary ambulance and secondary emergency facility should also simultaneously equip emergency-line in order to communication with each other. 4) Emergency care facilities. Primary emergency care facilities should be covered with the ambulatory emergency patients-minor illness and injuires. Secondary emergency care facilities should be covered with the emergency admission patients. Third emergency care center should be covered with the critical patients who need special treatments and operation. Secondary and third emergency care facilities should employ emergency medical doctor and emergency nurse specialist to treat in-patients with severe and acute illness and multiple injuires. It should be fashioned for a system of emergency facilities that meets emergency patients needs. Provide incentives for increased number of emergency care facilities with traning in personal/clinical emergency care. 5) Finance It is recommended to put the finance of a emergency care on a firm basis. The emergency care delivery system should be managed by the government or accreditted organizations. In order to facilitate this relevant program the fund is needed for more efficient and effective emergency researchs, service, programs, and policy. 6) Gaining understanding and co-operation of pubic It is also important to undertake pubic education to improve understanding of first aids and C. P. R of individuals, communities and business. It is proposed that teachers and health officers be certified in C. P. R. The C. P. R education can be powerful influence save lives. Lastly appropriate emergency care information must be provided to the pubic for assisting them in choosing emergency care.

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