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A Statistical Review on States Relating to Operation of Radiotherapy Equipments in Seoul National University Hospital (서울대학교병원의 방사선치료장비 운용 통계에 관한 고찰)

  • Park, Heung-Deuk;Kim, Wan-Sun;Ahn, Hee-Yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.6 no.1
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    • pp.21-30
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    • 1994
  • To analyze the states of operation of radiotherapy facilities in the period from 1979 to 1992 and to get the base for efficient operation and maintenance of the radiotherapy facilities. Data on the records of annual number of patients operated by each facility; span of suspension of operation, the cost and span of repairing, and parts of oui-of-order in the period from 1979 to 1992 were analyzed. We made a comparative analysis of average annual number of patients, annual span of the suspension of operation, annual cost ratio of repair, span of repairing per break down, and total number of broken parts. We could get following annual number of patients(day), span of the suspension of span ($\%$)(day). annual cost ratio fo repair($\%$), span of repairing per break down(Min-Max, day), and number of broken parts from this analysis. 1. Cobalt unit (Picker C-9) : 10,389(43), 0.4(0.83) 0.07, 1hr-2, 3 2. Linac(Clinac 6/100) : 11,492(50), 4.0(9.57), 0.98, 1hr-30, 12 3. Linac(Clinac 18) : 9.115(44), 12.7(30.5), 3.54, 1hr-108. 41 4. Simulator(Picker Ther-X) : 2,017(9), 0.51(1.3), 0.24, 1hr-2, 7 5. RTP(Capentec Cap-plan) : 528(2), 0.4(0.93), - hrs, - The conclusion obtained from statistical analysis above are as follows. 1. The rate of operation of Cobalt unit($99.6\%$) was higher that of Linear Accelerators ($87.3\%$). The rates operation of Simulator and RTP computer were very close to that of Cobalt unit. 2. In order to raise up the working ratio of accelerator. it is desirable that we keep our engineer to learn a sufficient technical skill and the equipment agent to stock sufficient spare parts. 3. In order to maintain Linear Accelerator efficiently, it is desirable to have annually $2.3\%$ of the purchase price of equiment for repairing.

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Changes in Carbohydrate Components of Hard and Soft Wheat during Kernel Maturation (경(硬), 연질(軟質) 소맥(小麥)의 성숙(成熟)에 따른 탄수화물(炭水化物) 특성의 변화(變化))

  • Chang, Hak-Gil;Kyung, Kyu-Hang;Kim, Sung-Kon
    • Korean Journal of Food Science and Technology
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    • v.19 no.1
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    • pp.69-74
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    • 1987
  • These studies were conducted to investigate the changes in carbohydrate properties of the endosperm during the stages of maturity. Original moisture continued to decrease while 1,000-kernel weight and test weight increased steadily in all varieties with maturation. Starch content of the endosperm increased continuously by 35 to 40 days after heading. The B-type starch granules synthesis of the the early mature variety, Chokwang, was depressed at the later stages of development. Amylose and amylopectin components of starch both increased as the kernel matured, and amylose-amylopectin ratio also increased during the same period. Amount of pentosan per kernel basis increased throughout the maturation period. Amylograph break-down had a highly negative coefficient correlation with starch and pentosan content of endosperm. Results indicated that wheat maturation was characterized by an increase in the starch and pentosan content of the kernel.

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An Estimation Process of Effort and Cost in Security Evaluation of Information Technology Security Systems by utilizing Evaluation Work Break-down Structure (EWBS를 통한 정보보호 시스템의 보안성 평가 업무량 및 비용 산정 프로세스)

  • You, Hyung-Joon;Ko, Jeong-Ho;Chang, Soo-Jin;Ahn, Sun-Suk;Lee, Gang-Soo;Jung, Hong-Jin
    • Journal of KIISE:Software and Applications
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    • v.27 no.2
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    • pp.134-147
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    • 2000
  • Even though software industry has been activated, there lack in results of studies on evaluation effort and cost of software systems including Information Technology Security System (ITSS). In this paper, we present a process and a tool for evaluation effort and cost of ITSS, which are conformed to a ITSS evaluation criteria(i. e., Common Criteria or ISO/IEC 15408), by utilizing Evaluation Work Break-down Structure (EWBS) and conventional software development cost estimation methods. Even though we concentrate on ITSS, results of this paper can be applied to estimation of effort and cost of evaluation of software development process and software products.

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A Review of Withering in the Processing of Black Tea

  • Deb, Saptashish;Jolvis Pou, K.R.
    • Journal of Biosystems Engineering
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    • v.41 no.4
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    • pp.365-372
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    • 2016
  • Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.

Challenges in Competition Law in Homodeus Era (호모데우스 시대에서 경쟁법의 도전)

  • Shon, Donghwan
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.3
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    • pp.285-292
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    • 2021
  • In Sapiens it shows the reason that sapiens has conquered the earth for the invention of intersubjective reality. In Homodeus sapiens made the science revolution through the religion of humanism. The development of science showed that human free will and emotion is just made through the chemical interaction of neuron which can be manipulated and developed. Algorithm and data wlll be the sovereign which make decision in everything. Yuval Harari tells us the Homodeus appear and break down the order of equality. His anticipation proves right in competition law issues. The collusion through the algorithm makes it difficult to apply existing cartel logic. Agreement is the ground of responsibility but undertaking is not responsible in the market where sovereign algorithm decides eveything. Extreme price differentiation can appear and break down the existing market logic and competition dogma. Everything changes and it is necessary to have the flexible attitude and develop new logic.

Sutdies on Quality Characteristics of Jeju Mandarin Orange Jelly for the Aged (고령자용 감귤젤리의 품질 특성 연구)

  • Lee, Ji-Eun;Choi, Eun-Jung;Oh, Myung-Suk
    • Journal of the Korean Society of Food Culture
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    • v.22 no.4
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    • pp.475-481
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    • 2007
  • This study was carried out to determine the quality characteristics of Jeju mandarin orange jelly with various gelling agent such as agar, ${\kappa}-carrageenan$ and gellan gum for the aged. The concentration of agar was 0.4-0.6% and that of ${\kappa}-carrageenan$ and gellan gum was 0.2-0.4%. The color value, gelling temperature, melting temperature, break down rate, textural properties and sensory acceptance test of Jeju mandarin orange jelly with various gelling agent were measured. Average age of the subjects for acceptance test was 78.23. Redness and yellowness of Jeju mandarin orange jelly with agar was lower than that with ${\kappa}-carrageenan$. The gelling and melting temperature of Jeju mandarin orange jelly with agar was lowest among the jellies. Break down rate of Jeju mandarin orange jelly with agar was highest among the jellies. Above results showed that the stability of Jeju mandarin orange jelly with agar was inferior than that with ${\kappa}-carrageenan$ and gellan gum. Hardness, adhesiveness and springiness of Jeju mandarin orange jelly with agar was lowest among the jellies and sensory acceptance of Jeju mandarin orange jelly with gellan gum was highest among them. Thus, gellan gum was appropriate gelling agent for the Jeju mandarin orange jelly with regard to the acceptability and the depression of sour taste in Jeju mandarin orange jelly could improve the acceptability for the aged.

Comparison and Evaluation of Clothing Insulation of Newly-Developed Air-Filled Baffle Jackets and Down Padded Jackets (새롭게 개발된 겨울용 공기주입형 배플 패딩 재킷과 기존 방한 패딩 재킷들의 보온력 비교 평가)

  • Kwon, JuYoun;Kim, Siyeon;Baek, Yoon Jeong;Lee, Joo-Young
    • Fashion & Textile Research Journal
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    • v.23 no.2
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    • pp.261-272
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    • 2021
  • The purpose of the present study was to evaluate the thermal insulation of air-filled winter jackets according to the amount of air-filler using a thermal manikin. The insulation of these jackets' was compared to a down padded jacket with an identical design and size. The amounts of air-filler were 100% (26,219 cm3), 70% (18,645 cm3), 50% (13,110 cm3), and 0% (0 cm3). The results showed that a clothing insulation (Icl) of 0%, 50%, 70%, and 100% air, and 100% down jackets was 0.208, 0.243, 0.207, 0.176, and 0.315 clo, respectively. In addition, the down jacket with waisttaped had a clothing insulation of 0.369 clo. However, the highest value of clothing insulation per clothing weight was the 50% air-filled jacket in all conditions. In terms of regional power consumption of the thermal manikin, the down jacket consumed less power for the shoulder and chest than the air-filled jackets. In conclusion, in order to maximize the thermal insulation of air-filled jackets, an optimal amount of air-filler, that is, an amount which does not compromise (break) the layer of inner air between the surface of manikin and the lining of the jacket, should be explored. Further studies on lining materials, end-closed design, and changes in thermal insulation under the conditions of strong wind or heavy snow are recommended.

SAFETY ANALYSIS OF INCREASE IN HEAT REMOVAL FROM REACTOR COOLANT SYSTEM WITH INADVERTENT OPERATION OF PASSIVE RESIDUAL HEAT REMOVAL AT NO-LOAD CONDITIONS

  • SHAO, GE;CAO, XUEWU
    • Nuclear Engineering and Technology
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    • v.47 no.4
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    • pp.434-442
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    • 2015
  • The advanced passive pressurized water reactor (PWR) is being constructed in China and the passive residual heat removal (PRHR) system was designed to remove the decay heat. During accident scenarios with increase of heat removal from the primary coolant system, the actuation of the PRHR will enhance the cooldown of the primary coolant system. There is a risk of power excursion during the cooldown of the primary coolant system. Therefore, it is necessary to analyze the thermal hydraulic behavior of the reactor coolant system (RCS) at this condition. The advanced passive PWR model, including major components in the RCS, is built by SCDAP/RELAP5 code. The thermal hydraulic behavior of the core is studied for two typical accident sequences with PRHR actuation to investigate the core cooling capability with conservative assumptions, a main steam line break (MSLB) event and inadvertent opening of a steam generator (SG) safety valve event. The results show that the core is ultimately shut down by the boric acid solution delivered by Core Makeup Tank (CMT) injections. The effects of CMT boric acid concentration and the activation delay time on accident consequences are analyzed for MSLB, which shows that there is no consequential damage to the fuel or reactor coolant system in the selected conditions.

The adaptive filter configuration for down stream of Naktong river (낙동강 하류원수에 적합한 여과지의 여재구성)

  • Kim, Sang-goo;Ryou, Dong-choon;Lee, Yung-sik;Son, Jin-eun
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.95-95
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    • 1995
  • This study was carried out to evaluate the variations of headloss rate and of specific deposit to depths with effective size of media and configuration of filter layer during algae blooming period. 0.51mm size media was disqualified because most of headloss occurred rapidly below 5cm from surface layer however 0.91mm size media acted deep filtration more than 20cm from top, as result 0.91mm sixte media filter had 2∼3 times longer filtration time than 0.51mm sixte media filter, but 0.91mm size media have break-through potentiality. multi-layer filter with 1.02mm anthracite and 0.51mm sand had large deposit volume in upper layer that could longer filtration time, moreover smaller media in lower layer that could protect break-through.

SBLOCA AND LOFW EXPERIMENTS IN A SCALED-DOWN IET FACILITY OF REX-10 REACTOR

  • Lee, Yeon-Gun;Park, Il-Woong;Park, Goon-Cherl
    • Nuclear Engineering and Technology
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    • v.45 no.3
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    • pp.347-360
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    • 2013
  • This paper presents an experimental investigation of the small-break loss-of-coolant accident (SBLOCA) and the loss-of-feedwater accident (LOFW) in a scaled integral test facility of REX-10. REX-10 is a small integral-type PWR in which the coolant flow is driven by natural circulation, and the RCS is pressurized by the steam-gas pressurizer. The postulated accidents of REX-10 include the system depressurization initiated by the break of a nitrogen injection line connected to the steam-gas pressurizer and the complete loss of normal feedwater flow by the malfunction of control systems. The integral effect tests on SBLOCA and LOFW are conducted at the REX-10 Test Facility (RTF), a full-height full-pressure facility with reduced power by 1/50. The SBLOCA experiment is initiated by opening a flow passage out of the pressurizer vessel, and the LOFW experiment begins with the termination of the feedwater supply into the helical-coil steam generator. The experimental results reveal that the RTF can assure sufficient cooldown capability with the simulated PRHRS flow during these DBAs. In particular, the RTF exhibits faster pressurization during the LOFW test when employing the steam-gas pressurizer than the steam pressurizer. This experimental study can provide unique data to validate the thermal-hydraulic analysis code for REX-10.