• Title/Summary/Keyword: k-opt

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Convolution-Superposition Based IMRT Plan Study for the PTV Containing the Air Region: A Prostate Cancer Case (Convolution-Superposition 알고리즘을 이용한 치료계획시스템에서 공기가 포함된 표적체적에 대한 IMRT 플랜: 전립선 케이스)

  • Kang, Sei-Kwon;Yoon, Jai-Woong;Park, Soah;Hwang, Taejin;Cheong, Kwang-Ho;Han, Taejin;Kim, Haeyoung;Lee, Me-Yeon;Kim, Kyoung Ju;Bae, Hoonsik
    • Progress in Medical Physics
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    • v.24 no.4
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    • pp.271-277
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    • 2013
  • In prostate IMRT planning, the planning target volume (PTV), extended from a clinical target volume (CTV), often contains an overlap air volume from the rectum, which poses a problem inoptimization and prescription. This study was aimed to establish a planning method for such a case. There can be three options in which volume should be considered the target during optimization process; PTV including the air volume of air density ('airOpt'), PTV including the air volume of density value one, mimicking the tissue material ('density1Opt'), and PTV excluding the air volume ('noAirOpt'). Using 10 MV photon beams, seven field IMRT plans for each target were created with the same parameter condition. For these three cases, DVHs for the PTV, bladder and the rectum were compared. Also, the dose coverage for the CTV and the shifted CTV were evaluated in which the shifted CTV was a copied and translated virtual CTV toward the rectum inside the PTV, thus occupying the initial position of the overlap air volume, simulating the worst condition for the dose coverage in the target. Among the three options, only density1Opt plan gave clinically acceptable result in terms of target coverage and maximum dose. The airOpt plan gave exceedingly higher dose and excessive dose coverage for the target volume whereas noAirOpt plan gave underdose for the shifted CTV. Therefore, for prostate IMRT plan, having an air region in the PTV, density modification of the included air to the value of one, is suggested, prior to optimization and prescription for the PTV. This idea can be equally applied to any cases including the head and neck cancer with the PTV having the overlapped air region. Further study is being under process.

Effect of Phenol Formaldehyde Impregnation on The Physical and Mechanical Properties of Soft-Inner Part of Oil Palm Trunk

  • Hartono, Rudi;Hidayat, Wahyu;Wahyudi, Imam;Febrianto, Fauzi;Dwianto, Wahyu;Jang, Jae-Hyuk;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.6
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    • pp.842-851
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    • 2016
  • The objective of this study was to improve physical and mechanical properties of soft-inner part of oil palm trunk (S-OPT) after impregnation with phenol formaldehyde (PF) resin and densification by close system compression (CSC) method. Effect of different methods of PF resin impregnation (i.e., no vacuum-pressure, vacuum, and vacuum-pressure) was evaluated. The results showed that PF resin impregnation and CSC significantly improved the physical and mechanical properties of S-OPT up to: (1) 176% in density; (2) 309% in modulus of rupture (MOR); (3) 287% modulus of elasticity (MOE); and (4) 191% in the compressive strength. Physical and mechanical properties of S-OPT showed their best performances when PF resin impregnated with vacuum-pressure method as shown by higher weight gain, density, MOR, MOE, compressive strength, and lower recovery of set due to better penetration of PF resin into S-OPT. Combining PF resin impregnation and densification by CSC method could be a good method to improve physical and mechanical properties of S-OPT.

Quality Improvement of Oil Palm Trunk Properties by Close System Compression Method

  • Hartono, Rudi;Wahyudi, Imam;Febrianto, Fauzi;Dwianto, Wahyu;Hidayat, Wahyu;Jang, Jae-Hyuk;Lee, Seung-Hwan;Park, Se-Hwi;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.172-183
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    • 2016
  • Densification of the inner part of oil palm trunk (OPT) by the close system compression (CSC) method was performed in this study. The effects of the compression temperature and time on the anatomical, physical and mechanical properties of OPT were evaluated. The inner part of OPT with an initial average density of $0.3g/cm^3$ was used as samples. Oven-dried samples were immersed in water and vacuumed until fully saturated and then compressed by CSC at 120, 140, 160 or $180^{\circ}C$ for 10, 20, 30 or 40 min. The anatomical characteristics of transverse and radial sections before and after compression were compared by optical microscopy. The physical and mechanical properties, including the density, recovery of set (RS), modulus of elasticity (MOE), modulus of rupture (MOR), and compression parallel to grain were examined. It was observed that the anatomical characteristic of the inner part of OPT (i.e., vascular bundles, vessels, and parenchyma tissue) became flattened, fractured, and collapsed after compression by CSC. The RS decreased with increasing compression temperature and time. The lower RS indicated high dimensional stability. The physical and mechanical properties (i.e., density, MOR, MOE, and compressive strength) of the inner part of OPT increased with increasing compression temperature and time. Compression by the CSC method at $160^{\circ}C$ for 40 min was the optimum treatment.

Influence of substituted phenyl backbone on the fungicidal activity of phenyl or 2-pyridyl substituents in bis-aromatic ${\alpha},{\beta}$-unsaturated ketone derivatives (비스 방향족 $\alpha, \beta$ -불포화 케톤 유도체중 2-pyridyl 및 phenyl 치환체의 항균성에 관한 치환 phenyl backbone의 영향)

  • Sung, Nack-Do;Yu, Seong-Jae;Choi, Kyoung-Seob;Kim, Hyun-Jae
    • The Korean Journal of Pesticide Science
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    • v.2 no.3
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    • pp.45-51
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    • 1998
  • A series of bis-aromatic ${\alpha},{\beta}$-unsaturated ketone derivatives with mesaured fungicidal activities in vivo against rice blast(Pyricularia oryzae), tomato leaf blight (Phytophtora infestans) and barley powdery mildew(Erysiphe graminis) were studied by using quantitative structure activity relationship equations. The QSAR model for the activity of phenyl substituents, $1{\sim}11$, clearly reveals three important factors, namely, resonance(R<0), optimal molecular hydrophobicity(${\pi})_{opt.}=0.38$) and optimal distance($((L_{1})_{opt.}=5.69({\AA}))$ of substituent, respectively. But in case of 2-pyridyl substituents, $12{\sim}28$, the activity were governed by optimal molecular refractivity $((M_{R})_{opt.}=8.04{\sim}39cm^{3}/mol)$, steric effect(Es<0) and LUMO energy(e.v). The fungicidal activity relationship of phenyl and 2-pyridyl substituents against Erysiphe graminis have been proportioned.

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The complexity of opt-in procedures in mobile shopping: Moderating effects of visual attention using the eyetracker (모바일 쇼핑에서 옵트인의 절차적 복잡성 연구: 아이트래커(eyetracker) 기반 시각적 주의의 조절효과)

  • Kim, Sang-Hu;Kim, Yerang;Yang, Byunghwa
    • Journal of Digital Convergence
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    • v.15 no.8
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    • pp.127-135
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    • 2017
  • Consumers tend to feel concern about disclosure of personal information and, at the same time, to avoid inconvenience of procedural complexity caused by the privacy protections. The purpose of current paper is to investigate relationships between opt-in procedural complexity and shopping behavior using smart phones, moderating by the amount of visual attentions using eyetrackers. Therefore, we created a virtual mobile Web-site in which the complexity of opt-in procedures in our experiment is manipulated and measured. Also, we measured the dwell-time of area of interest using SMI-RED 250 instrument for tracking the real eye movement. Results indicated that the levels of procedural complexity are related to repurchase, indicating a moderating effect of the amount of visual attentions. Finally, we discussed several theoretical and practical implications of management for mobile commerce.

Comparative Effects of Phytase Derived from Escherichia coli and Aspergillus niger in Sixty Eight-week-old Laying Hens Fed Corn-soy Diet

  • Yan, L.;Zhou, T.X.;Jang, H.D.;Hyun, Y.;Kim, H.S.;Kim, I.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.10
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    • pp.1391-1399
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    • 2009
  • Two hundred and sixteen 68-week-old Hy-Line brown laying hens were used in a 6-week feeding trial to compare the efficacy of phytases Optiphos (OPT) and Natuphos (NAT), which were isolated from Escherichia coli and Aspergillus niger, respectively. Hens were randomly allotted into six treatments with six replications (six layers in three adjacent cages) per treatment according to their initial BW. The hens were then subjected to one of the following dietary treatments: i) Positive Control (PC; available phosphorus (AP) 0.4%); ii) Negative control (NC; AP 0.2%); iii) NAT1 (NC+250 FTU/kg NAT); iv) NAT2 (NC+500 FTU/kg NAT); v) OPT1 (NC+250 FTU/kg OPT); vi) OPT2 (NC+500 FTU/kg OPT). Feed intake, egg production, egg quality, apparent nutrient digestibility and serum P and Ca concentration were evaluated to compare the effect of the two phytases. Feed intake and eggshell thickness were not affected by the treatments. Superior effects (p<0.05) of OPT were only observed in egg production and egg weight compared with NAT. Characteristics such as eggshell breaking strength, apparent digestibility of N, Ca and P and serum P concentration were equally increased with the supplementation of both phytases (p<0.05), where no significant difference was observed in those characteristics between PC and phytase supplementation at 500 FTU/kg. Equally effective improvements (p<0.05) were also observed in egg production and DM digestibility, where no improvements were observed (p<0.05) between the PC group and the groups with phytase supplementation at 500 FTU/kg. Equal increases in the serum Ca level were observed when the groups with phytase supplementation were compared to the PC group. Overall, the results of this study suggest that NAT and OPT are equally effective at liberating phytate-bound complexes when included in 0.2% available phosphorus diets for 68-week laying hens; either source of phytase can be fed to commercial 68-week laying hens at 500 FTU/kg to correct the negative effects associated with a 0.2% available phosphorus diet. In conclusion, either source of phytase can be fed to commercial first cycle laying hens at 500 FTU/kg to effectively replace inorganic phosphorus when economically justified.

Optimization of optical design for Eye Glass Display

  • Moon, H.C.;Kim, T.H.;Park, K.B.;Park, Y.S.;Seok, J.M.;Kim, H.W.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1603-1606
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    • 2005
  • Eye Glass Display (EGD) with microdisplay to realize the virtual display can make the large screen, so virtual image has been developed by using microdisplay panel. This paper shows study of low cost lens design and simulation for microdisplay system with 0.6" Liquid Crystal on Silicon (LCoS) panel. Lens design optimized consider to spherical aberration, astigmatism, distortion, and chromatic aberration. Code V is used and it designed an aspheric lens about exit pupil 6mm, eye relief 20mm and 35 degree of field of view (FOV). With the application this aspheric lens to LCOS type's microdisplay, virtual image showed 50 inch at 2m. One side of the aspheric lens was constituted from diffractive optical element (DOE) for the improvement in a performance. It had less than ${\pm}2%$ of distortion value and modulation transfer function in axial had 20% of resolution with 30 lp/mm spatial frequency. The optical system is suitable for display of 0.6"-diagonal with SVGA.

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Study on High Aspect Ratio Wing and Optimization of Substructure Location by Using EDISON OPtimal Triangle membrane(Linear and Non-linear analysis) - Static (EDISON OPT 평면요소를 이용한 고 세장비 날개에 대한 선형, 비선형 비교연구 및 추가구조물 위치 최적화)

  • Lee, Da-Woon;Hong, Yoou-Pyo;Shin, Sang-Joon
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.262-267
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    • 2016
  • In this paper, to design Human Powered Aircraft(HPAC) with high aspect ratio wing which behave with large displacement under lift distribution causing a failure itself, then steel wire has been designed to prevent its failure. unit load method is used to calculate reaction force on wire and Optimal Triangle(OPT) membrane is employed to analyze its main wing spar with large displacement. EDISON CSD solver, linear static analysis and co-rotational nonlinear static anaysis both using OPT membrane produce behaviors of beam for each case of wire location about main wing spar, and aerodynamic coefficient also, by using aerodynamic analysis tool.

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Exceptional Characteristics of Cross-border Production Networks in Dandong, North Korea-China Border Region (북중 접경지역 단둥의 대북 생산 네트워크의 예외적 성격)

  • Lee, Sung-Cheol;Kim, Boo-Heon;Chung, Su-Yeul;Kim, Minho;Chi, Sang-Hyun
    • Journal of the Economic Geographical Society of Korea
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    • v.20 no.3
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    • pp.329-352
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    • 2017
  • Since the late 2000s Korean foreign direct investors in North Korea and China border regions have gone through the closure of outward processing trade(OPT) networks and changes in their location due to UN security council resolution and Korean independent sanctions against North Korea's nuclear and missile tests. However, the introduction of new Chinese OPT policy has led to the invigoration of domestic market-based OPT networks towards North Korea. The main aim of this paper is to identify the exceptional characteristics of Dandong in Liaoning province, a North Korea and China border region by analyzing OPT networks towards North Korea. Fundamentally the establishment of OPT networks towards North Korea is likely to be based on the utilization of a plenty of low wages in North Korea. The main reasons for this are fallen into two perspectives: geo-economics and geo-politics. The first perspective is geo-economics centering on the consolidation of economic exchange between North Korea and China, and North Korean economic development. For example, the introduction of Chinese OPT in border region has enabled Chinese local firms based on domestic market to access a plenty of low wage in North Korea in formal and institutional contexts. The second is geo-politics for the stability of North Korean regime based on the means of geo-economics. As the invigoration of domestic market-based OPT networks might make North Korea possible promoting foreign money earning, it enable North Korea to be sustainable as a buffering region between capitalist and socialist regime for China. It shows Chinese geo-strategic attempts to deal with the economic and regime stability of North Korean as a buffering state. In other words, OPT networks in North Korea should be concerned with the discourse practice of geo-economics and geo-politics which might lead to various and contingent spatial economies in border region. As a consequence, North Korea and China border regions could defined as a space in which is applicable to exceptional institutions and policies, and an exploitative space in which create surplus and rents by utilizing a plenty of low wages in North Korea through OPT networks.

Evaluation of water holding property for applying a cosmetic moisturizer from oil palm trunk CNF (오일 팜 수간 유래 CNF (cellulose nanofibrils)의 화장품 보습제 적용을 위한 보습력 평가)

  • Song, Woo-Yong;Shin, Soo-Jeong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.2
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    • pp.91-98
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    • 2016
  • Cellulose nanofibrils (CNF) was made from oil palm trunk (OPT) with soda-anthraquinone pulping, chlorine dioxide bleaching, carboxymethylation, followed by mechanical grinding. Size of this CNF was 16-40 nm of width confirmed by TEM. To evaluate CNF from OPT as cosmetics raw materials for moisturizing component, water holding properties was compared with hyaluronic acid and collagen. CNF from OPT had better water holding property than collagen or hyaluronic acid whether phenoxyethanol was added as antiseptic or without additive.