• 제목/요약/키워드: Origin Criterion

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THE QUEST FOR COSMIC RAY PROTONS IN GALAXY CLUSTERS

  • PFROMMER C.;ENSSLIN T. A.
    • 천문학회지
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    • 제37권5호
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    • pp.455-460
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    • 2004
  • There have been many speculations about the presence of cosmic ray protons (CRps) in galaxy clusters over the past two decades. However, no direct evidence such as the characteristic $\gamma$-ray signature of decaying pions has been found so far. These pions would be a direct tracer of hadronic CRp interactions with the ambient thermal gas also yielding observable synchrotron and inverse Compton emission by additionally produced secondary electrons. The obvious question concerns the type of galaxy clusters most likely to yield a signal: Particularly suited sites should be cluster cooling cores due to their high gas and magnetic energy densities. We studied a nearby sample of clusters evincing cooling cores in order to place stringent limits on the cluster CRp population by using non-detections of EGRET. In this context, we examined the possibility of a hadronic origin of Coma-sized radio halos as well as radio mini-halos. Especially for mini-halos, strong clues are provided by the very plausible small amount of required CRp energy density and a matching radio profile. Introducing the hadronic minimum energy criterion, we show that the energetically favored CRp energy density is constrained to $2\%{\pm}1\%$ of the thermal energy density in Perseus. We also studied the CRp population within the cooling core region of Virgo using the TeV $\gamma$-ray detection of M 87 by HEGRA. Both the expected radial $\gamma$-ray profile and the required amount of CRp support this hadronic scenario.

Draw resonance in polymer processing: a short chronology and a new approach

  • Hyun, Jae-Chun
    • Korea-Australia Rheology Journal
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    • 제11권4호
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    • pp.279-285
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    • 1999
  • Draw resonance is both an important and interesting instability encountered in various extensional-deformation-dominated polymer processing operations. It is important because of its paramount relevance to the productivity and quality issue in the related industry: and it is interesting because of as yet unanswered questions as to what its cause and origin are in terms of physics involved. Specifically, a short chronological account of the draw resonance research is presented in this paper bringing several previous results together and focusing on the derivation of a new criterion for draw resonance based on the interaction of the traveling times of some kinematic waves propagating along the spinline from the die exit to the take-up position. The new explanation of draw resonance put forward here based on the physics of the system is seen to have wide implications on both theoretical and practical aspects of draw resonance instability. The importance of the role played by spinline tension in determining draw resonance is an example of the former whereas interpretation of the mechanism of the draw resonance eliminator is an example of the latter. Finally, an approximate yet a very fast and convenient method for determining draw resonance is also derived based on the above findings and found to agree well with the exact stability results.

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정량분석을 통한 Eleutherococcus species의 HPLC 분석법 검증과 표준화 (Standardization of Eleutherococcus species and HPLC Method Validation for Quantitative Analysis)

  • 송미경;김미연;김호철
    • 대한본초학회지
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    • 제26권1호
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    • pp.103-110
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    • 2011
  • Objective : For the standardization and quality control of eleutheroside E in Eleutherococcus species, HPLC analysis was performed and eleutherosdie E content was compared in 23 kinds of Eleutherococcus species collected from Korea and China. Methods : The content of eleutheroside E in stem bark of Eleutherococcus species collected from Korea and China were analyzed by HPLC. 0.5% phosphoric acid and acetonitrile was used as mobile solvent. Validation of HPLC analysis method was confirmed by analyzing specificity, linearity, precision and accuracy following ICH guideline. Results : Content of eleutheroside E was determined to be 1.0-1.6% and 0.5-0.8% in Korean and Chinese E. senticosus, respectively. Content of eleutheroside E in E. sessiliflorus was 0.7-1.1% and 0.2-0.4% respectively in Korean and Chinese origin. All calibration curves showed good linear regression. The method showed good precision and accuracy with intra-day and inter-day variations of 0.880-3.442% (RSD) and 0.606-3.328% (RSD), respectively, and average recovery was of 0.141-1.363% (RSD), for the eleutheroside E analyzed. Conclusion : These results might be used to establish a criterion of eleutheroside E in Eleutherococcus species.

Multiaxial ratcheting assessment of Z2CND18.12N steel using modified A-V hardening rule

  • Xiaohui Chen;Yang Zhou;Wenwu Liu;Xu Zhao
    • Steel and Composite Structures
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    • 제49권1호
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    • pp.1-17
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    • 2023
  • Based on Ahmadzadeh-Varvani hardening rule (A-V model), multiaxial ratcheting effect of Z2CND18.12N austenitic stainless steel is simulated by ABAQUS with user subroutine UMAT. The results show that the predicted results of the origin multiaxial A-V model are lower than the experimental data, and it is difficult to control ratcheting strain rate. In order to improve the predicted capability of A-V model, the A-V model is modified. In this study. Moreover, under the assumption of the von Mises yield criterion and normal plasticity flow rule, we develop a numerical algorithm of plastic strain with the improved model to implement the finite element calculation of the model. Internal iteration in the numerical algorithm was implemented with the Euler backward method, which calculated the trial strain for each equilibrium iteration using the consistent tangent matrix. With a user subroutine, the proposed model is programmed into ABAQUS for a user - executable version. By simulating the uniaxial ratcheting of a round bar made of Z2CND18.12N austenitic stainless steel, we observe that the predicted results simulated by ABAQUS with UMAT are compared with the experimental data. The predicted results of the improved multiaxial A-V model are consistent well with the experimental data.

GC-SAW(Surface Acoustic Wave) 전자코를 활용한 볶은 커피의 원산지 및 배합 커피의 상품별 분류 (Application of GC-SAW(Surface Acoustic Wave) Electronic Nose to Classification of Origins and Blended Commercial Brands in Roasted Ground Coffee Beans)

  • 서한석;강희진;정은희;황인경
    • 한국식품조리과학회지
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    • 제22권3호통권93호
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    • pp.299-306
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    • 2006
  • The numerous varieties of coffee beans contain a wide range prices and qualities. While the varieties of green coffee beans can generally be distinguished by their appearance, this visual criterion is impossible after the roasting process. Therefore, we need to develop a classification method or device. In this study, the potential of a new type of electronic nose, fast gas chromatography based on a surface acoustic wave sensor(SAW), was evaluated for the classification of origins and blended commercial brands in roasted coffee beans. Eight blended commercial brands and the origins of four similarly roasted ground coffee beans(with no significant difference of color) were rapidly(90 sec/sample) classified. The reproductive results were easily understandable over the aroma image pattern by $VaporPrint^{TM}$. In conclusion, GC-SAW electronic nose can be applied to the classification of origins and commercial brands in roasted ground coffee beans and to e evaluation of the similarities and differences of volatile pattern between samples.

Genetic Analysis of Growth Response to Cold Water Irrigation in Rice

  • Han, Long-Zhi;Koh, Hee-Jong
    • 한국작물학회지
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    • 제45권1호
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    • pp.26-31
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    • 2000
  • This study was carried out to obtain the basic information for breeding cold-tolerant rice varieties with high yield-productivity through wide crosses between indica and japonica rice. Genetic analysis was conducted using 55 F$_1$s obtained from half-diallel crosses among eleven cultivars of various origin including indica and japonica rice. Screening for cold tolerance was done with cold-water irrigation after transplanting until ripening stage. Both general combining ability (GCA) and specific combining ability (SCA) effects were highly significant in all characters associated with dry matter accumulation at 30 and 50days after cold-water irrigation (DAC). The variance of GCA was much larger than that of SCA in plant height, shoot dry weight per plant (DWP), crop growth rate (CGR) and cold-water response index (CRI) of these characters except CRI of shoot dry weight per plant. The DWP, CGR and CRI of these characters of Gaochan 102, Tong88-7 and TR22183 were markedly higher than those of the others. GCA effects of these varieties on DWP, CGR and their CRI were also higher than those of the others, indicating that they are useful as promising parents for breeding cold-tolerant varieties. Analysis of genetic parameters for 11$\times$11 half-diallel F$_1$s revealed that inter-locus gene interaction were concerned in the expression of plant height at 50 DAC, CRI of DWP at 50 DAC, and CRI of CGR, and that intra-locus gene interaction for plant height and the other characters were partial dominance and over-dominance, respectively. Narrow-sense heritability (h$^2$$_{N}$) was the highest in plant height as 0.729, and the lowest in CRI of DWP at 30 DAC as 0.048, suggesting that selection for cold tolerance will be quite effective in case that the selection criterion is the performance itself.f.

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동작정보 추출을 위한 가변적 탐색 영역과 블록 크기의 정합 (Size-Variable Block Matching for Extracting Motion Information)

  • 장석우;김봉근;김계영;최형일
    • 정보처리학회논문지B
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    • 제10B권3호
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    • pp.321-328
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    • 2003
  • 본 논문에서는 영상으로부터 블록 단위의 동작벡터를 추출하기 위해 가변적인 크기의 블록을 사용하는 정합 방법을 제안한다. 제안된 정합 알고리즘은 탐색영역의 크기를 적응적으로 조절하고, 보다 정확한 동작벡터를 추출할 때가지 블록의 크기를 동적으로 설정한다. 본 논문에서는 탐색영역의 중심위치를 결정하기 위해 시간의 경과에 따른 블록의 동작변화는 작다고 가정한다. 또한, 탐색영역의 범위는 공간적으로 인접한 블록들의 동작 균일성에 따라 조절된다. 블록의 크기를 결정하는 과정은 작은 크기의 블록에서부터 정합을 시작한다. 정합 정확도가 좋을 경우 블록의 크기를 조금 확대한 후 본 논문에서 정한 정합 기준이 만족될 때가지 정합 과정을 반복한다. 실험 결과는 제안한 가변적인 블록정합 방법이 보다 정확한 블록 단위의 동작벡터를 추출함을 보여준다.

Measurement of Port Service Quality in Container Transport Logistics Using Importance -Performance Analysis: A Case of Busan Port

  • Ha, Min-Ho;Ahn, Ki-Myung
    • 한국항해항만학회지
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    • 제41권5호
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    • pp.353-358
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    • 2017
  • This study aims to propose an assessment tool of port service quality (PSQ) in the context of container transport logistics (CTLs), by taking the perspectives from port users. The CTLs defined in this study are the relevant activities of serving the physical flows of a container box from a point of origin via a container port to a point of destination. To address the ports' role in collaboration between its channel members in CTLs, the PSQ measures for all port user groups (i.e. common PSQ measures) are selected based on the relevant CTLs activities involved by port, and its users within terminal/port area as well as throughout the CTLs chain. An importance-performance analysis (IPA) is applied as a diagnostic tool to analyse the status quo of Busan Port in CTLs contexts, by comparing the importance and performance (IP ) scores against each individual CTLs criterion. The findings from the IPA reveal that port managers and policy makers at the Busan Port should concentrate on six PSQ measures (i.e. SR1, SR4, ITS1, VAS1, VAS4, ICI3) to enhance PSQ in CTLs. However, four measures (i.e. ITS2, ITS3, ITS4, VAS2) are identified as a possible overkill, indicating an area of inefficiency where a remedial action of the cost-cutting decision is necessary. On the other hand, the Busan port shows an outstanding performance on four measures such as SR2, SR3, ICI1 and ICI2. The measures are not only important but also high performance. The study findings provide managerial guidance to port managers in Busan Port, in view of searching for managerial and operational strategies for sustainable port growth.

Characteristics of South Korea's Geothermal Water in Relation to Its Geological and Geochemical Feature

  • Lee, Chung-Mo;Hamm, Se-Yeong;Lee, Cholwoo;Choi, Sung-Ja;Chung, Sang Yong
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제19권2호
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    • pp.25-37
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    • 2014
  • The volcanic type of geothermal water is linked intimately to active or potentially active volcanoes and takes place near the plate boundaries. In contrast to the volcanic type, the geothermal water in Korea has a non-volcanic origin. Korea's geothermal water is classified into the residual magma (RM) type and deep groundwater (DG) type according to the criterion of $35^{\circ}C$. This study reviewed the relationship between the physical and chemical features of the 281 geothermal water sources in South Korea in terms of the specific capacity, water temperature, and chemical compositions of two different basements (igneous rock and metamorphic rock) as well as the geological structures. According to the spatial relationship between the geothermal holes and geological faults, the length of the major fault is considered a key parameter determining the movement to a deeper place and the temperature of geothermal water. A negligible relationship between the specific capacity (Q/s) and temperature was found for both the RM type and DG type with the greater specific capacities of the RM- and DG-igneous types than the RM- and DG-metamorphic types. No relationship was observed between Q/s and the chemical constituents ($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, $Zn^{2+}$, $Cl^-$, $SO_4{^{2-}}$, $HCO_3{^-}$, and $SiO_2$) in the DG-igneous and DG-metamorphic types. Furthermore, weak relationship between temperature and chemical constituents was found for both the RM type and DG type.

방사선(放射線)으로 조사(照射)된 Polyvinylchloride의 내방사성(耐放射性) 전기전도도(電氣傳導度)에 가소제(可塑劑)가 미치는 영향(影響) (Effects of Plasticizer to Radioresistance and Electrical Conductivity of Irradiated Polyvinylchlorde)

  • 김봉흡
    • Journal of Radiation Protection and Research
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    • 제3권1호
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    • pp.23-28
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    • 1978
  • 유기석계(有機錫系) 안정제(安定劑)를 포함하고 있는 polyvinylchloride (PVC)의 내방사성(耐放射性)은 가소제(可塑劑)로서 첨가된 dioctylphthalate(DOP)의 양의 증가와 더부러 증가하며 이와 같은 내방사성(耐放射性)의 평가는 시료의 IR 특성 상에서 안정제의 해이(解離)에 기인(起因)하고 있는 $1,540{\sim}1,640cm^{-1}$에서의 흡수대가 선량과 더부러 변화하는 거동으로 살필 수 있다. 가소화된 PVC에서의 내방사성의 증가는 DOP 분자구조의 일부를 형성하는 benzen 환(環)에서 방사 에너지가 공명흡수 되기 때문이라 사료(思料)되며 이와 같은 견해(見解)는 방사선량에 대한 도전율변화특성(導電率變化特性)의 고찰 결과와도 잘 일치 한다. 실용적면(實用的面)에서 $0{\sim}100Mrad$ 사이의 선량에 대한 충분(充分)한 내방사성(耐放射性)을 얻기 위하여는 30phr 전후의 DOP 첨가량이 필요하다.

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