• Title/Summary/Keyword: laeA

Search Result 1,290, Processing Time 0.035 seconds

The Comparison of Beam Data between Measured Beam Data and Calculated Beam Data Using Treatment Planning System (6 MV 광자선의 측정데이터와 치료계획장치에 의한 계산데이터의 비교)

  • Park Sung Kwang;Cho Byung Chul;Cho Heung Lae;Ahn Ki Jung
    • Progress in Medical Physics
    • /
    • v.16 no.3
    • /
    • pp.125-129
    • /
    • 2005
  • The first step in the commissioning procedure of a treatment planning system is always verification of the basic beam data. In this work, we have measured POD curves and beam profiles between 1 $\times$ 1 cm$^{2}$ and 40 $\times$ 40 cm$^{2}$ . In an attempt, Pinnacle 7.4f detect discrepancies between predicted dose distribution and delivered dose distribution. The discrepancies between measurement data and caculation data was found. The delivered dose was underestimated in field but overestimated out of field. The D$_{max}$ depth of 1 $\times$ 1 cm$^{2}$ was reduced about 2 mm. For the larger field size ($\geq$4$\times$4 cm$^{2}$, the beam profile and PDD curve showed good agreement between measurement data and calculation data.

  • PDF

Investigation on Harmful Trace Elements in Some Food Additives (식품첨가물중(食品添加物中) 유해미량금속(有害微量金屬) 함량(含量)에 관(關)하여)

  • Kirn, Jeung-Ok;Song, Jae-Chul;Young, Han-Chul;Ha, Yeung-Lae
    • Journal of Nutrition and Health
    • /
    • v.12 no.3
    • /
    • pp.25-32
    • /
    • 1979
  • In order to investigate harmful trace elements in ford additives used in food processing the contents of Copper, Lead, Cadmium, Chromium, Manganese, Nickel and Iron are determined by Atomic Absorption Spectrophotometer. These Elements are Extracted with APDC-MIBK extract method. Samples are collected from the food Industrial companies in Korea. Samples studied as shown in Table 1 are food colors(3-samples, Flavoring Agents(7-samples), Acidifiers(4-samples) Baking Powders(4-samples), Emulsifiers(2-samples), Thickeners(2-samples), Antioxidants(2-samples), Intensifiers(2-samples), Seasonings(3-samples), modifiers (10-samples) Most of the food additives contained comparatively a little small amount of harmful trace elements. However, the contents of harmful trace elements of Sodium Carbonate, Food Yellow No.5, Food Blue No.1, Food Red No.2 and Alkalies added in noodles are significantly higher than the other food additives. The obtained results are as follows ; 1) Sodium Carbonate contained Cadmium; 16.73 ug/g and Lead ; 61.55 ug/g. 2) Food Yellow No. 5 contained Cadmium: 1.67ug/g and Lead; 23.46 ug/g. 3) Food Blue No. 1 contained Cadmium; 1. 16 ug/g and Lead; 23.46 ug/g. 4) Food Red Ho. 1 contained Cadmium; 1.91 ug/g and Lead 23.08 ug./g. 5) Alkalies added in noodles contained Cadmium; 6. 11 ug/g and Lead; 53.85 ug/g.

  • PDF

Nn Evaluation of Climate Change Effects on Pollution Loads of the Hwangryong River Watershed in Korea (기후변화에 따른 황룡강 유역의 오염부하 유출량 변화 분석)

  • Park, Min Hye;Cho, Hong-Lae;Koo, Bhon Kyoung
    • Journal of Korea Water Resources Association
    • /
    • v.48 no.3
    • /
    • pp.185-196
    • /
    • 2015
  • A conceptual watershed model HSPF (Hydrological Simulation Program-Fortran) was applied to the Hwangryong river watershed to evaluate climate change effects on pollution loads of the river. For modeling purposes, the Hwangryong river watershed was divided into 7 sub-watersheds. The model was calibrated and validated for the river discharges against the data observed in 2011 at several monitoring stations. The RCP scenarios were set up for the model simulations after being corrected by change factor method. The simulation results of the RCP 4.5 scenario indicate that the annual river discharge and concentrations of BOD, TN, TP of the Hwangryong river will continually increase during the second-half of the 21st century. As for the RCP 8.5 scenario, the simulations results imply that the pollution loads will increase during the middle of the 21st century reflecting the pattern of precipitation. Monthly distributions of the pollution loads for the RCP 4.5 and the RCP 8.5 scenarios show it will increase the most in September and February, respectively.

A study on the therapeutic effects of Topiramate according to the types of migraine (편두통의 형태에 따른 Topiramate의 치료효과 - 무 전조 편두통, 전조 편두통, 그리고 개연적 편두통에 대한 topiramate의 치료 효과 및 치료이후의 임상경과 -)

  • Lee, Jun-Hwa;Cho, Kyung-Lae
    • Clinical and Experimental Pediatrics
    • /
    • v.53 no.4
    • /
    • pp.554-559
    • /
    • 2010
  • Purpose : The purpose of this study was to evaluate whether the therapeutic effects of topiramate differ according to the types of migraine. Methods : We recruited 38 children and adolescents with migraine who had been treated with topiramate. The effect of topiramate was evaluated on the basis of the change in the frequency of migraine attacks after treatment. Results : Among patients having migraine with aura, 85.7% showed complete recovery, 1 (7.1%) showed partial recovery, and 1 did not show any recovery. Among patients having migraine without aura, 47.1% showed complete recovery, 29.4 % showed partial recovery, and 23.5% showed no recovery. Among patients suspected with migraine, 1 (20%) showed complete recovery, 1 (20%) showed partial recovery, and 3 (60%) showed no recovery. Conclusion : Our results indicated that topiramate exhibited excellent therapeutic effects for migraine accompanied with aura, and it was effective in migraine without aura. However, the effect of topiramate in patients suspected with migraine was uncertain.

Lipid Oxidation in Roasted Fish Meat 1. Rancidity in Roasted and/or Reheated Dark Muscled Fish (어육의 배소에 의한 지질산화에 관한 연구 I. 적색육어의 배소 및 재가열에 의한 지질의 산패)

  • LEE Kang-Ho;CHO Ho-Sung;LEE Jong-Ho;SHIM Ki-Hwan;HA Yeoung-Lae
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.30 no.5
    • /
    • pp.708-713
    • /
    • 1997
  • Various chemical indices were analyzed to clarify the tendency of rancidity during the repeats of heating so called roasting heating and/or reheating in dark muscled fish (mackerel and pacific saury). The total lipid contents of fresh mackerel and pacific saury were $36.7\%\;and\;28.4\%$ in saturated fatty acid, $33.0\%\;and\;20.2\%$ in monoenoic acid, and $29.9\%\;and\;49.7\%$ in polyenoic acid, respectively. The ratios of unsaturated fatty acid (UFA)/Saturated fatty acid (SFA) were 1.7, 2.5 and content of total lipid was $16.5\%\;and\;13.7\%$, respectively. Peroxide content gradually increased after roasting heating and reheating in mackerel while it decreased after reheating in pacific saury. Thiobarbituric acid value also increased during roasting and heating in all the samples but decreased after reheating. Acid value increased after roasting heating and reheating in all samples, particularly it was high in pacific saury which have a high composition of UFA. More conjugated dienes were formed when the meat was roasted at $180^{\circ}C$ than at $200^{\circ}C\;or\;220^{\circ}C$, and in the filet with skin than the skinless.

  • PDF

Estimation of Computed Tomography Dose in Various Phantom Shapes and Compositions (다양한 팬텀 모양 및 재질에 따른 전산화단층촬영장치 선량 평가)

  • Lee, Chang-Lae
    • Journal of radiological science and technology
    • /
    • v.40 no.1
    • /
    • pp.13-18
    • /
    • 2017
  • The purpose of this study was to investigate CTDI (computed tomography dose index at center) for various phantom shapes, sizes, and compositions by using GATE (geant4 application for tomographic emission) simulations. GATE simulations were performed for various phantom shapes (cylinder, elliptical, and hexagonal prism PMMA phantoms) and phantom compositions (water, PMMA, polyethylene, polyoxymethylene) with various diameters (1-50 cm) at various kVp and mAs levels. The $CTDI_{100center}$ values of cylinder, elliptical, and hexagonal prism phantom at 120 kVp, 200 mAs resulted in 11.1, 13.4, and 12.2 mGy, respectively. The volume is the same, but $CTDI_{100center}$ values are different depending on the type of phantom. The water, PMMA, and polyoxymethylene phantom $CTDI_{100center}$ values were relatively low as the material density increased. However, in the case of Polyethylene, the $CTDI_{100center}$ value was higher than that of PMMA at diameters exceeding 15 cm ($CTDI_{100center}$ : 35.0 mGy). And a diameter greater than 30 cm ($CTDI_{100center}$ : 17.7 mGy) showed more $CTDI_{100center}$ than Water. We have used limited phantoms to evaluate CT doses. In this study, $CTDI_{100center}$ values were estimated and simulated by GATE simulation according to the material and shape of the phantom. CT dosimetry can be estimated more accurately by using various materials and phantom shapes close to human body.

Effects of Preflocculated Filler Flocs and Nano-sized Coating Binder on Fold Cracking of Coated Paper (충전물 선응집체 크기와 나노 바인더에 의한 도공지의 접힘터짐 변화)

  • Im, Wanhee;Seo, Dongil;Oh, Kyudeok;Jeong, Young Bin;Youn, Hye Jung;Lee, Hak Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.47 no.5
    • /
    • pp.91-97
    • /
    • 2015
  • Papermakers wish to increase the filler content of printing and writing grades because it allows saving in production cost through fiber replacement and improving the formation, and optical and printing properties of the paper. However, high filler loading in the base paper has negative side effects. It reduces the mechanical properties of paper and induces cracking at the fold after coating process. Fold cracking is one of the most frequent quality complaints for magazines, high quality books, etc. Two approaches were examined as methods to reduce fold cracking. One approach was to use preflocculated fillers, which was expected to reduce the fold cracking because it would decrease the interfiber bonding. The other approach was to use a new coating binder that gives greater binding power and thereby provides an opportunity of reducing the fold cracking of coated paper. When filler preflocculation was employed in producing the base paper, fold cracking becomes more severe than conventional filler loading condition. On the other hand, use of nano sized binder in coating improved the tensile properties of the coating layer and thereby decreased the crack area. It was shown that tensile properties of coating layer played an important role in fold cracking of coating.

Study on Manufacture of Korean Paper(Hanji) Sludge-Wood Fiber Composite Boards I. Physical Properties of Korean Paper(Hanji) Sludge-Wood Fiber Composite Boards (한지슬러지-목재섬유 복합보드의 제조연구 I. 한지슬러지-목재섬유 복합보드의 물리적 성질)

  • Lee, Phil-Woo;Lee, Hak-Lae
    • Journal of the Korean Wood Science and Technology
    • /
    • v.27 no.2
    • /
    • pp.23-30
    • /
    • 1999
  • This study was carried out to develop the Korean paper(Hanji) sludge-wood fiber composite boards utilizing the relinquished sludges occurring from the making process of Korean classic paper Hanji. The bark of paper mulberry(Broussonetia kazinoki Sieb.) has been used as a raw material since past hundreds and thousands years. Korean paper(Hanji) sludge was divided into two kinds, the one was the white sludge from the first stage and the other was the black sludge occurring from the final stage of Korean paper(Hanji) making. Four levels of the mixed ratio of each white or black sludge to wood fiber(10:90, 20:80, 30:70 and 40:60), three levels of the resin adhesives(PMDI, urea and phenol resin) and three levels of the density(0.60, 0.75 and 0.90) were designed to investigate the physical properties of Korean paper(Hanji) sludge-wood fiber composite boards. From the results and discussion, it could be concluded as follows : 1. In the white sludge-wood fiber composite board, the thickness swelling was not affected by the specific gravity and sludge additive of composite boards, but among the resin adhesives PMDI resin showed the best dimensional stability. Water absorption was superior in urea resin, secondly PMDI resin and very poor in phenol resin. 2. In the black sludge-wood fiber composite board, thickness swelling was superior in PMDI resin but very poor in phenol resin. In water absorption, PMDI and urea resin showed good results, regardless of specific gravity or sludge additive, but phenol resin showed poor results. 3. From the results and discussion of physical properties it is suggested that the white sludge-wood fiber composite boards bonded with PMDI or black sludge-wood fiber composite boards bonded with urea resin were made possibly with similar or better properties. compared with general fiberboard until the addition of 20% sludge into wood fiber.

  • PDF

Study on Manufacture of Korean Paper(Hanji) Sludge-Wood Fiber Composite Boards II. Mechanical Properties of Korean Paper(Hanji) Sludge-Wood Fiber Composite Boards (한지슬러지-목재섬유 복합보드의 제조연구 II. 한지슬러지-목재섬유 복합보드의 기계적 성질)

  • Lee, Phil-Woo;Lee, Hak-Lae
    • Journal of the Korean Wood Science and Technology
    • /
    • v.27 no.2
    • /
    • pp.31-37
    • /
    • 1999
  • This study was carried out to develop the Korean paper(Hanji) sludge-wood fiber composite boards utilizing the relinquished sludges occurring from the making process of Korean classic paper Hanji. The bark of paper mulberry(Broussonetia kazinoki Sieb.) has been used as a raw material since past hundreds and thousands years. Korean paper(Hanji) sludge was divided into two kinds, the one was the white sludge from the first stage and the other was the black sludge occurring from the final stage of Korean paper(Hanji) making. Four levels of the mixed ratio of each white or black sludge to wood fiber(10:90, 20:80, 30:70 and 40:60), three levels of the resin adhesives(PMDI, urea and phenol resin) and three levels of the density(0.60, 0.75 and 0.90) were designed to investigate the mechanical properties of Korean paper(Hanji) sludge-wood fiber composite boards. From the results and discussion, it could be concluded as follows : 1. In the white and black sludge-wood fiber composite boards, bending modulus of rupture showed the clear decreasing tendency according to the increase of sludge additive, but it was clearly increased with the increase of specific gravity. Modulus of elasticity showed the same tendency as in the modulus of rupture, and also tensile and internal bonding strength had the same tendencies as in these bending properties. 2. Among the resin adhesives, PMDI or urea resin showed great values in MOR of white sludge-wood fiber composite board, but urea resin was greater than PMDI in MOR and MOE of black sludge-wood fiber composite board. Tensile and internal bonding strength showed the same tendencies as in white sludge-wood fiber composite board. 3. It is suggested that the white sludge-wood fiber composite boards bonded with PMDI or black sludge-wood fiber composite boards bonded with urea resin were able to made similar boards to general fiberboard by the mixed ratio 20:80 of sludge to wood fiber.

  • PDF

Ontology Based Semantic Information System for Grid Computing (그리드 컴퓨팅을 위한 온톨로지 기반의 시맨틱 정보 시스템)

  • Han, Byong-John;Kim, Hyung-Lae;Jeong, Chang-Sung
    • Journal of Internet Computing and Services
    • /
    • v.10 no.4
    • /
    • pp.87-103
    • /
    • 2009
  • Grid computing is an expanded technology of distributed computing technology to use low-cost and high-performance computing power in various fields. Although the purpose of Grid computing focuses on large-scale resource sharing, innovative applications, and in some case, high-performance orientation, it has been used as conventional distributed computing environment like clustered computer until now because Grid middleware does not have common sharable information system. In order to use Grid computing environment efficiently which consists of various Grid middlewares, it is necessary to have application-independent information system which can share information description and services, and expand them easily. Thus, in this paper, we propose a semantic information system framework based on web services and ontology for Grid computing environment, called WebSIS. It makes application and middleware developer easy to build sharable and extensible information system which is easy to share information description and can provide ontology based platform-independent information services. We present efficient ontology based information system architecture through WebSIS. Discovering appropriate resource for task execution on Grid needs more high-level information processing because Grid computing environment is more complex than other traditional distributed computing environments and has various considerations which are needed for Grid task execution. Thus, we design and implement resource information system and services by using WebSIS which enables high-level information processing by ontology reasoning and semantic-matching, for automation of task execution on Grid.

  • PDF