• Title/Summary/Keyword: Periodic Review

Search Result 189, Processing Time 0.027 seconds

SPECTRAL PROPERTIES OF GALACTIC AND EXTRAGALACTIC BLACK HOLE CANDIDATES

  • CHAKRABARTI SANDIP K.
    • Journal of The Korean Astronomical Society
    • /
    • v.29 no.spc1
    • /
    • pp.223-225
    • /
    • 1996
  • We review current theoretical understanding of the spectral properties (low and high states, transition of states, quasi-periodic oscillations etc.) of the low mass as well as supermassive black hole candidates.

  • PDF

Comparative Study on Korea and French Men's Bat - During 17th Century to 18th Century - (한국과 프랑스의 남성 모자 비교연구 - $17{\sim}18$세기를 중심으로 -)

  • Yang, Ji-Na;Lee, Sang-Eun
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.9 no.2
    • /
    • pp.115-125
    • /
    • 2007
  • A hat is a general term for what human beings wear on their heads in order to protect them from the cold or heat, to be used for ornament, or to symbolize social position. A hat represents the position of a man who wears it, attitude toward the society, and faith for a religion for males. Since men's hats can create their image and uniqueness in casual wear from current fashion items, they are proposed as a fashion accessory item of designers each season. The purpose of this study is to review hats, which are part of costume, in a more analytic method. The research range of this study is hats for men in the upper class in the 17th to 18th centuries from the history of costume when diverse periodic and characteristic costume changes occurred. In the 17th to 18th centuries in the middle of the Chosun Dynasty, changes in costume occurred as the feudal society of the dynasty had been dissolved since the Japanese invasion in 1592. Political power was established in France as the Baroque Age began in the 17th century. Since European costume, especially women's costume led fashion in France, the country represented the age better than any other countries. Aristocratic costume in the Rococo Age of the 18th century was changed to completely different shape of costume after the French Revolution. In this regard, this age was deemed to be the most appropriate for the comparison or costume. Another purpose of this study is to review the common and different features of periodic factors that affect changes in costume by researching the hats of the two countries in the same age in order to understand relation between periodic characteristics and costume throughout history of costume.

  • PDF

Periodic Lateralized Epileptiform Discharges Are lctal Phenomena, and Need an Antiepileptic Treatment (주기편측간질모양방전은 발작현상으로서 항경련제 치료가 필요하다)

  • Kim, Jae-Moon
    • Annals of Clinical Neurophysiology
    • /
    • v.13 no.1
    • /
    • pp.21-25
    • /
    • 2011
  • Periodic lateralized epileptiform discharges (PLEDs) had been debated whether it is ictal or non-ictal phenomenon. As most of PLEDs occur in patients with acute structural lesions, some epileptologists prefer PLEDS as a non-ictal phenomenon, rather an obscure epiphenomenon of etiological diseases. But, almost half of the patients with PLEDs do not have acute structural lesions in the brain and metabolic disorders or old CNS lesions may cause PLEDs and even more, no brain lesion was identified in some patients. There are many data supporting PLEDs as ictal phenomena. Occurrence of PLEDs usually accompanied by decreased mentality and is improved as PLEDs disappeared. Current SPECT study showed marked hyperperfusion in the lesion side of PLEDs, that is striking evidence of PLEDs as ictal phenomena. Also careful review of EEG with PLEDs revealed it is a dynamic process rather than a static state. Despite of these evidences, as PLEDs are an end-stage of animal status epilepticus models, it may be a transition of ictal to interictal state.

Periodic Safety Review of Wolsong Unit 1 - Environmental Impact as gaseous and liquid effluents (월성 1호기 주기적안전성평가 - 기체 및 액체 방사성폐기물에 의한 환경영향)

  • 김성민;이은미;김미자;이갑복;정양근;엄희문
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2003.11a
    • /
    • pp.455-462
    • /
    • 2003
  • According to Korean nuclear code requires Periodic Safety Review(PSR) every 10 years should be perform for operating reactor, and selects the eleven PSR safety factors. Among them the review objective of the environmental impact is to determine whether the operator has an adequate programme for surveillance of the environmental impact of the nuclear power plant based on current safety standards. In this paper, the environmental impact in PSR of Wolsong Unit 1 was reflected current safety standards as of the evaluation date. As a result, all items generally satisfied the standards, and the staff also verified that the population dose due to the operation of Wolsong Unit 1 was controlled safely as of the evaluation date.

  • PDF

Review of Aging Management for Concrete Silo Dry Storage Systems

  • Donghee Lee;Sunghwan Chung;Yongdeog Kim;Taehyung Na
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.21 no.4
    • /
    • pp.531-541
    • /
    • 2023
  • The Wolsong Nuclear Power Plant (NPP) operates an on-site spent fuel dry storage facility using concrete silo and vertical module systems. This facility must be safely maintained until the spent nuclear fuel (SNF) is transferred to an external interim or final disposal facility, aligning with national policies on spent nuclear fuel management. The concrete silo system, operational since 1992, requires an aging management review for its long-term operation and potential license renewal. This involves comparing aging management programs of different dry storage systems against the U.S. NRC's guidelines for license renewal of spent nuclear fuel dry storage facilities and the U.S. DOE's program for long-term storage. Based on this comparison, a specific aging management program for the silo system was developed. Furthermore, the facility's current practices-periodic checks of surface dose rate, contamination, weld integrity, leakage, surface and groundwater, cumulative dose, and concrete structure-were evaluated for their suitability in managing the silo system's aging. Based on this review, several improvements were proposed.

Periodic Mesoporous Organosilicas (유/무기 하이브리드형 실리카 나노세공체)

  • Park, Sung Soo;Ha, Chang-Sik
    • Journal of Adhesion and Interface
    • /
    • v.21 no.3
    • /
    • pp.113-122
    • /
    • 2020
  • Mesoporous materials are a sort of promising materials with a wide spectrum of applications due to their unique well-defined porous structures that provide high surface area and controllable pore size. Among mesoporous materials, periodic mesoporous organosilicas (PMOs) are highly emerging materials in sense of applications due to their large pore sizes and organic functionality in the frame. The organic functional groups in the frameworks of these solids allow tuning of the surface properties and modification of the bulk properties of the material. This article provides a comprehensive overview of PMOs and discusses their different functionalities, morphology and applications, such as catalysis, environmental applications, and adsorption, for which PMOs have been used after their discovery. The review article will provide fundamental understanding of PMOs and their advanced applications to readers.

Net Inventory Positions in Systems with Non-Stationary Poisson Demand Processes

  • Sung, Chang-Sup
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.6 no.2
    • /
    • pp.51-55
    • /
    • 1981
  • In both continuous-review and periodic-review non-stationary inventory systems, the non-stationary Poisson demand process and the associated inventory position processes were proved being mutually independent of each other, which lead to the probability distribution of the corresponding net inventory position process in the form of a finite product sum of those two process distributions. It is also discussed how these results can correspond to analytical stochastic inventory cost function formulations in terms of the probability distributions of the processes.

  • PDF

A Sufficient Condition for the Independence of Non-Stationary Demand Process and Inventory Position Process under < Q, r > Systems

  • Sung, C.S.
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.8 no.1
    • /
    • pp.22-28
    • /
    • 1982
  • Under a continuous-review inventory system, the inventory position process was proved to be asymptotically independent of the general renewal demand processes, when the two processes form an asymptotic unimodel joint distribution. The analytical technique implemented through this work seems to be more like general, and so the periodic-review system can be similarly investigated. In conclusion, the results may be evaluated to direct to the analytical analyses of some inventory systems which have been treated under some restrictions on demand processes.

  • PDF

Development of CANDU Reactor Aging Monitor (CANDU형 원전 경년열화 감시시스템(Aging Monitor) 개발)

  • Kim, Hong Key;Choi, Young Hwan;Ko, Han Ok
    • Transactions of the Korean Society of Pressure Vessels and Piping
    • /
    • v.5 no.2
    • /
    • pp.13-19
    • /
    • 2009
  • As the operating time in nuclear power plants (NPPs) increases, the integrity of nuclear components may be continually degraded due to aging effects of systems, structures and components. Recently, a number of NPPs are being operated beyond their design life to produce more electricity without shutting down. The critical issue in extending a lifetime is to maintain the level of safety during the extended operation period while satisfying the international regulatory standards. Therefore, it is beneficial to build a monitoring system to measure an aging status. In this paper, the Aging Monitor (AM) based on lots of aging database obtained from the operating plants and research results on the aging effects was developed to monitor, manage and evaluate the aging phenomena systematically and effectively in NPPs. The AM for the CANDU is divided into 6 modules: (1) Aging Alarm/Coloring Monitor, (2) Aging Database, (3) Aging Document, (4) Real-time Integrity Monitor, (5) Surveillance and Inspection Management System, and (6) Continued Operation and Periodic Safety Review (PSR) Safety Evaluation. The proposed system is expected to provide the integrity assessment for the major mechanical components of an NPP under concurrent working environments.

  • PDF