• Title/Summary/Keyword: Leakage control

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Leakage and Scattered Radiation from X-ray Unit in Radiography (영상의학과 엑스선 발생장치의 누설 및 산란선량 측정)

  • Im, In-Chul;Lee, Jae-Seung;Kweon, Dae-Cheol
    • Journal of the Korean Society of Radiology
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    • v.5 no.3
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    • pp.155-159
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    • 2011
  • The purposed of this study were measured the radiation exposure of patients and workers by generators, and the protection state for radiation facilities. The subject of the study by X-ray generators in university hospitals of capital area, we measured the maximum irradiation condition of 80 kVp, 200 mA, 0.1 second in the control entrance, control room window, entrance of radiography, adjacent site. The leakage dose per week was which the control entrance was 0.11 mR/week, control room window was 0.15 mR/week, entrance of radiography was 0.12 mR/week and adjacent site was 0.06 mR/week with X-ray unit the mean And the leakage mean dose was 0.11 mR/week. Diagnostic X-ray tubes must ensure that the leakage radiation in the maximum leakage dose in week emitted by the tube outside the useful beam does not exceed certain levels provided by standards.

IN VITRO STUDY ON MARGINAL LEAKAGE OF COMPOSITE RESIN INLAY RESTORATIONS (광중합 복합레진 INLAY 수복물의 변연누출에 관한 실험적 연구)

  • Yoo, Je-Kug;Bae, Jeong-Sik;Lee, Ho-Yong
    • The Journal of Korean Academy of Prosthodontics
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    • v.26 no.1
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    • pp.85-98
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    • 1988
  • The primary aim of this study was to access the degree of marginal leakage in composite resin inlay restorations. Class V cavities were prepared on sixty extracted premolars. They were classified as control group and experimental group 1, 2 and each group was filled with BIS-FIL $I^{(R)}$ and $Silux^{(R)}$ composite resins. In the control group, the composite resin was inserted directly, the experimental group 2 was inserted as composite resin inlay after heat treatment on $125^{\circ}C$, 10 minutes. Then thermocycling was performed 1000 times. After staining with 1% Basic Fuchsin, they were cut in Buccolingual direction and the degree of penetration of the dye was examined under L/M. The following results were obtained : 1. In occlusal margin area, difference in marginal leakage was not observed in all groups. 2. In gingival margin area, cavities filled with composite resin inlay was less marginal leakage than filled directly in BIS-FIL $I^{(R)}$ group, and statistical significant difference was not existed in $Silux^{(R)}$ group. 3. The statistical significance was not existed between composite resin inlay and composite resin inlay heated secondarily. 4. In all groups, gingival margin area reveals more marginal leakage than occlusal margin area and statistical significance was existed.

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A Study on the Automatic Sensing Device for Gas Leakage of Cooling Plate Using the Microprocessor System

  • Wang, Jee-Seok;Yoon, Hee-Jong;Kang, Ki-Seong;Kim, Jong-Do
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.3
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    • pp.329-334
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    • 2011
  • The cooling water circulation plates had been used to drop the temperature of refractory outside shell of common cooling system by using cooling plate or stave type. When they are attacked by surrounding gas, they are corroded and the water flows in the refractory due to leakage of water. So, the life of refractory material is shortened and changed due to the worse conditions of cooling system. The automatic sensing device for water leakage of cooling plate is developed to check the position of trouble by using the microprocessor system when cooling water leak and gas are flowed into the cooling plate through the leakage position. The flowed gas is detected in the micro-process system which delivers the detected position of cooling plate or stave to main control room through the wireless-radio relay station. This system can be possible to detect the position of cooling plate or stave against the water leakage part immediately and then deliver the signal to main control room by using the microprocessor system and wireless-radio relay station. This system will be developed in changing the working condition from manual system to unmanned auto alarm system.

A STUDY OF THE APICAL LEAKAGE OF VARIOUS RETROGRADE FILLING MATERIALS (Retrograde filling시 수종 충전재료에 따른 폐쇄효과에 대한 연구)

  • Do, Jeong-Wook;Kwon, Hyuk-Choon
    • Restorative Dentistry and Endodontics
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    • v.14 no.1
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    • pp.97-105
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    • 1989
  • This study was conducted to evaluate and compare the apical leakage among the retrograde filling materials; retrograde filling with non-zinc amalgam, cavity varnish and non-zinc amalgam, z.o.e cement, Glass Ionomer cement, scotch bond and silux. Sixty single rooted teeth were divided into six groups and each tooth was individually prepared for its particular group. The specimens were incubated at $37^{\circ}C$ for 24 hrs and then were infiltrated by 2% methylene blue for 7 days. Apical leakage was evaluated by measuring the degree of dye penetration between the filling material and the canal wall. The results were as follows: 1. The scotch bond and silux group showed the least amount of apical leakage and the control group showed the greatest amount of apical leakage. 2. The groups retrofilled with cavity varnish and amalgam, glass-Ionomer cement, scotch bond and silux showed significantly good apical seal than control group. 3. The groups retrofilled with glass Ionomer cement, scotchbond and silux showed significantly good apical seal than the groups retrofilled with Amalgam and Zinc oxide eugenol cement.

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Piosk : A Practical Kiosk To Prevent Information Leakage

  • Lee, Suchul;Lee, Sungil;Oh, Hayoung;Han, Seokmin
    • International journal of advanced smart convergence
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    • v.8 no.2
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    • pp.77-87
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    • 2019
  • One of important concerns in information security is to control information flow. It is whether to protect confidential information from being leaked, or to protect trusted information from being tainted. In this paper, we present Piosk (Physical blockage of Information flow Kiosk) that addresses both the problems practically. Piosk can forestall and prevent the leakage of information, and defend inner tangible assets against a variety of malwares as well. When a visitor who carries a re-writable portable storage device, must insert the device into Piosk installed next to the security gate. Then, Piosk scans the device at the very moment, and detects & repairs malicious codes that might be exist. After that, Piosk writes the contents (including sanitized ones) on a new read-only portable device such as a compact disk. By doing so, the leakage of internal information through both insiders and outsiders can be prevented physically. We have designed and prototyped Piosk. The experimental verification of the Piosk prototype implementation reveals that, Piosk can accurately detect every malware at the same detection level as Virus Total and effectively prevent the leakage of internal information. In addition, we compare Piosk with the state-of-the-art methods and describe the special advantages of Piosk over existing methods.

Low Leakage Input Vector Searching Techniques for Logic Circuits at Standby States (대기상태인 논리 회로에서의 누설전류 최소화 입력 탐색 방법)

  • Lee, Sung-Chul;Shin, Hyun-Chul
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.10
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    • pp.53-60
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    • 2009
  • Due to increased integration density and reduced threshold voltages, leakage current reduction becomes important in the semiconductor IC design for low power consumption. In a combinational logic circuit, the leakage current in the standby state depends on the values of the input. In this research, we developed a new input vector control method to minimize the leakage power. A new efficient algorithm is developed to find the minimal leakage vector. It can reduce the leakage current by 15.7% from the average leakage current and by 6.7% from the results of simulated evolution method during standby or idle states for a set of benchmark circuits. The minimal leakage input vector, with idle input signal, can also reduce the leakage current by 6.8% from the average leakage current and by 3.2% from the results of simulated evolution method for sequential circuits.

AN in vitro STUDY OF THE CORONAL LEAKAGE OF TWO ROOT CANAL FILLING TECHNIQUE USING ANAEROBIC BACTERIAL LEAKAGE MODEL (근관 충전된 치아에서의 혐기성세균을 이용한 치관부 미세누출측정에 관한 연구)

  • Kim, Jin-Woo
    • Restorative Dentistry and Endodontics
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    • v.24 no.3
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    • pp.490-494
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    • 1999
  • The aim of this in vitro study was to investigate the coronal leakage of obligate anaerobes into root canals obturated with two different techniques. 48 extracted human teeth with straight, single root canals were prepared with crown-down technique with Profile under copious irrigation until the master apical file was size 40. The teeth were divided randomly into experimental groups (40 teeth) and control groups (8 teeth). In the experimental groups, 20 teeth were obturated with lateral condensation and other 20 teeth were obturated with continuous wave technique with System B. Coronal leakage of two root canal filing technique was evaluated using anaerobic bacterial leakage model with Fusobacterium nucleatum(ATCC 25586) for 60 days. The results were as follows 1. The incidence of bacterial leakage of experimental groups was 65% in group 1 (lateral condensation) and 60% in group 2 (continuous wave technique with System B). This difference was not statistically significant (P>0.05). 2. There was no statistically significant difference(P>0.05) in leakage score between group 1 (lateral condensation) and group2 (continuous wave technique with System B).

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Evaluation on the leakage of ground-water through fractured rock under a spillway (여수로 구조물 하부 암반 내 발달한 절리들을 통한 지하수 누수량 분석)

  • Kim, Hyoung-Soo;Lee, Ju-Hyun;Jeong, Ui-Jin;Lee, Joong-Woo
    • Journal of the Korean Geophysical Society
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    • v.9 no.2
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    • pp.129-134
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    • 2006
  • Recently, spillways are need to control stable water level for supporting main dams because of floods by unusual change of weather such as Typhoon Rusa. This study has been focused on the amount of leakage through the rock mass distributed fractures and joints under the opened emergency spillway. It is very important to evaluate the amount of leakage as these affect stability of spillway by interaction between effective stress and pore pressure. The commercial program MAFIC has been used for analyzing groundwater flow in fractured rock mass. The results showed that the values of range, average and deviation of leakage were 2.85∼3.79×10-1, 3.32×10-1 and 1.70×10-2 m3/day/m2 respectively. Secondary, we have estimated the effect of grouting after the transmissivity(Tf) of joint 1 as main pathway of leakage known from above results was changed from 1.78×10-7 to 1.59×10-9 m2/s. The results showed that the values of range, average and deviation of leakage were 7.80×10-4∼1.53×10-3, 1.18×10-3 and 1.32×10-4 m3/day/m2 respectively. As the result, the amount of leakage after grouting has been decreased by a ratio of 1 to 277.

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Effect of Protective Compounds on the Survival, Electrolyte Leakage, and Lipid Degradation of Freeze-Dried Weissella paramesenteroides LC11 During Storage

  • Yao, Amenan A.;Wathelet, Bernard;Thonart, Philippe
    • Journal of Microbiology and Biotechnology
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    • v.19 no.8
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    • pp.810-817
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    • 2009
  • The effect of cryoprotectants (maltodextrin+glycerol) and cryoprotectants+antioxidant [ascorbic acid and/or butylated hydroxytoluene (BHT)] mixtures on the survival, electrolyte leakage, and lipid degradation of freeze-dried Weissella paramesenteroides LC11 during storage was investigated and compared with that of the control (cells without additives) over a 90-day storage period at 4 or $20^{\circ}C$ in glass tubes with water activity ($a_w$) of 0.23. The survival, electrolyte leakage, and lipid degradation were evaluated through colony counts, electrical conductivity, and thiobarbituric acid reactive substances (TBARS) content, respectively. The fatty acids composition was determined by gas chromatography, in both the total lipid extract and the polar lipid fraction, and compared with that of the control after the 90-day storage period. As the storage proceeded, increases in leakage value and TBARS content, as well as a decrease in viability, were observed. After 90 days of storage, the major fatty acids found in both the total lipid extract and the polar lipid fraction were palmitic (16:0), palmitoleic (16:1), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) acids. The survival, leakage value, TBARS content and 18:2/16:0 or 18:3/16:0 ratio were the greatest for the protected strain held at $4^{\circ}C$. Cells with the cryoprotectants+BHT mixture showed the highest percentage of survival and 18:2/16:0 or 18:3/16:0 ratio in both lipid extracts, as well as the lowest leakage value and TBARS content after the 90-day storage period. Drying cells with the cryoprotectants+BHT mixture considerably slowed down polar lipid degradation and loss of membrane integrity, resulting in improved viability during storage.

Leakage detection of pipeline system based on modeling and identification (모델링과 검증에 의한 파이프 라인 시스템의 유출 탐지)

  • ;;;Lee, K. S.;Song, H. K.
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.905-910
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    • 1991
  • This paper presets a leakage detection method based on modeling the leakage in pipeline systems. For gas pipeline systems, a method based on the state space model is suggested. For liquid pipeline systems, an experiment based on the static model equation was performed. In the experiment, it was possible to detect the leak and to diagnosis the leak situation within the error of .+-.3%.

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