• 제목/요약/키워드: proximity function

검색결과 92건 처리시간 0.033초

Numerical Modeling for the $H_2/CO$ Bluff-Body Stabilized Flames

  • Kim, Seong-Ku;Kim, Yong-Mo;Ahn, Kook-Young;Oh, Koon-Sup
    • Journal of Mechanical Science and Technology
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    • 제14권8호
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    • pp.879-890
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    • 2000
  • This study investigates the nonpremixed $H_2/CO$-air turbulent flames numerically. The turbulent combustion process is represented by a reaction progress variable model coupled with the presumed joint probability function. In the present study, the turbulent combustion model is applied to analyze the nonadiabatic flames by introducing additional variable in the transport equation of enthalpy and the radiative heat loss is calculated using a local, geometry independent model. Calculations are compared with experimental data in terms of temperature, and mass fraction of major species, radical, and NO. Numerical results indicate that the lower and higher fuel-jet velocity flames have the distinctly different flame structures and NO formation characteristics in the proximity of the outer core vortex zone. The present model correctly predicts the essential features of flame structure and the characteristics of NO formation in the bluff-body stabilized flames. The effects of nonequilibrium chemistry and radiative heat loss on the thermal NO formation are discussed in detail.

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A Machine Learning Based Method for the Prediction of G Protein-Coupled Receptor-Binding PDZ Domain Proteins

  • Eo, Hae-Seok;Kim, Sungmin;Koo, Hyeyoung;Kim, Won
    • Molecules and Cells
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    • 제27권6호
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    • pp.629-634
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    • 2009
  • G protein-coupled receptors (GPCRs) are part of multi-protein networks called 'receptosomes'. These GPCR interacting proteins (GIPs) in the receptosomes control the targeting, trafficking and signaling of GPCRs. PDZ domain proteins constitute the largest protein family among the GIPs, and the predominant function of the PDZ domain proteins is to assemble signaling pathway components into close proximity by recognition of the last four C-terminal amino acids of GPCRs. We present here a machine learning based approach for the identification of GPCR-binding PDZ domain proteins. In order to characterize the network of interactions between amino acid residues that contribute to the stability of the PDZ domain-ligand complex and to encode the complex into a feature vector, amino acid contact matrices and physicochemical distance matrix were constructed and adopted. This novel machine learning based method displayed high performance for the identification of PDZ domain-ligand interactions and allowed the identification of novel GPCR-PDZ domain protein interactions.

최적화된 퍼지로직 기반 이동로봇의 지능주행 알고리즘 (Intelligent Navigation Algorithm for Mobile Robots based on Optimized Fuzzy Logic)

  • 조연;이홍규
    • 전기전자학회논문지
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    • 제22권2호
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    • pp.440-445
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    • 2018
  • 본 논문은 미지 유동환경에서 다중 이동로봇들의 주행문제에 대한 연구결과이다. 여기에서 환경은 로봇에게는 알려져 있지 않기 때문에 로봇의 몸체에 부착된 근접센서들을 이용하여 주변환경들을 감지하여야 하고, 로봇이 충돌 없이 경로를 추적하여 목표지점에 도착하도록 기본 방책들을 조합한 지능주행 방법을 제안하였다. 이러한 대부분 기법들은 퍼지논리 제어기들을 이용하여 구현하였으며, 모든 로봇에 동일하게 적용하였다. 퍼지 제어기의 성능을 향상시키기 위해서 유전 알고리즘을 이용하여 퍼지 제어기의 membership function과 rules set를 진화시켰다. 모의실험 결과 제안한 방법이 주행문제에 긍정적인 결과가 있음이 증명되었다.

영상처리를 이용한 Mark 판독 기법에 관한 연구 (A Study on the Mark Reader Using the Image Processing)

  • 김승호;김범진;이용구;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.83-83
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    • 2000
  • Recently, Vision system has being used all around industry. Sensor systems are used for Mark Reader, for example, optical scanning is proximity sensor system, have many disadvantages, such as, lacking user interface and difficulty to store original specimens. In contrast with this, Vision systems for Mark Reader has many advantages, including function conversion to achieve other work, high accuracy, high speed, etc. In this thesis, we have researched the development of Mark Reader by using a Vision system. The processing course of this s)'stem is consist to Image Pre-Processing such as noise reduction, edge detection, threshold processing. And then, we have carried out camera calibration to calibrate images which are acquired from camera. After searching for reference point within scanning area(60pixe1${\times}$30pixe1), we have calculated points crossing by using line equations. And then, we decide to each ROI(region of interest) which are expressed by four points. Next we have converted absolute coordinate into relative coordinate for analysis a translation component. Finally we carry out Mark Reading with images classified by six patterns. As a result of experiment which follows the algorithm has proposed, we have get error within 0.5% from total image.

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메뚜기 (Euprepocnemis shirakii) 성충의 혈구유형 (Hemocyte Types in Adult Grasshpper, Euprepocnemis shirakii Bolivar)

  • 장병수;한성식;여성문
    • Applied Microscopy
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    • 제24권2호
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    • pp.93-104
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    • 1994
  • Six types of hemocytes were identified in adult grasshopper, Euprepocnemis shirakii Bolivar. The morphological and ultrastructural characteristics of these cells were characterized by phase contrast, scanning and transmission electron microscope. The prohemocytes are small and spherical cells with large nucleus. The plasmatocytes are spindle shaped or polymorphic cells which show numerous cytoplasmic processes on the cell surface and they have lysosomes and vesicles that may be involved in phagocytic function. Especially, multivesicular bodies are observed in the polymorphic cells. The granulocytes I are spherical shaped cells. They are characterized by a number of electron dense granules measuring $0.2-0.3{\mu}m$ in average diameter and marginal band of microtubules which are always in close proximity to the cell membrane. The granulocytes II are oval or spindle-shaped cells. They contain large electron dense granules measuring $0.5-0.8{\mu}m$ in average diameter. Their cytoplasm is filled with numerous granules. The spherulocytes contain large amounts of spherules that most of their cytoplasm. Spherules filled with fine granules or flocculent materials. The oenocytoids are large spherical cells with few cytoplasmic organelles. Their cytoplasm contains peculiar aspect of motochondria and numerous polyrobosome.

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Syringe Infusion-based Contactless Atmospheric Pressure Ionization Mass Spectrometry for Small and Large Biomolecules

  • Lo, Ta-Ju;Chang, Chia-Hsien;Chen, Yu-Chie
    • Mass Spectrometry Letters
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    • 제3권4호
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    • pp.87-92
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    • 2012
  • In this study, we explored a new approach for generating ions of organics and biomolecules using contactless atmospheric pressure ionization (C-API). That is, a tapered capillary (~20 cm) was connected to a syringe, which was coupled to a syringe pump for providing a given flow rate to introduce sample solution to the proximity of a mass spectrometer. The gas phase ions derived from analytes were readily formed in the capillary outlet, which was very close to the mass spectrometer (~1 mm). No external electric connection was applied on the capillary emitter. This setup is very simple, but it can function as an ion source. This approach can be readily used for the analysis of small molecules such as amino acids and large molecules such as peptides and proteins. The limit of the detection of this approach was estimated to be ~10 pM when using bradykinin as the sample. Thus, we believe that this approach should be very useful for being used as an alternative ion source because of its low cost, high sensitivity, simplicity, and ease of operation.

유아기 손자녀를 둔 조모의 역할유형과 관련 변인들 : 사회인구학적 특성, 조모-손자녀 접촉 정도 및 조모-모 친밀감 (Types of Grandmothers with Preschool-Aged Grandchildren and Its Correlates : Demographic Characteristics, Contacts between Grandmothers and Grandchildren, and Closeness between Grandmothers and Mothers)

  • 김재희;도현심
    • 아동학회지
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    • 제32권1호
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    • pp.13-29
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    • 2011
  • The objective of this study was to identify role types as they pertain to paternal and maternal grandmothers based on four role dimensions. To this end, a sample of 416 mothers of preschoolers was used. This study also examined correlates of and differences in the type of grandparents in terms of paternal and maternal types of grandmothers. Data were analyzed by K-means clustering, Chi-square, and multi-nominal logistic regression analysis. Grandmothers were classified into five distinct groups : influential, supportive, authority-oriented, passive, and detached types. Maternal grandmothers seemed to be relatively more involved with their grandchildren than paternal ones. The type of grandmothers varied as a function of socioeconomic status, the number of grandchildren, and geographical proximity for paternal grandmothers, and mothers' employment status and the closeness between grandmothers and mothers for maternal grandmothers. The results imply that grandmothers are currently becoming more active in their grandchildren's lives and that kinship in Korean society tends to lean to the maternal side.

Performance evaluation of METAMIC neutron absorber in spent fuel storage rack

  • Kim, Kiyoung;Chung, Sunghwan;Hong, Junhee
    • Nuclear Engineering and Technology
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    • 제50권5호
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    • pp.788-793
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    • 2018
  • High-density spent fuel (SF) storage racks have been installed to increase SF pool capacity. In these SF racks, neutron absorber materials were placed between fuel assemblies allowing the storage of fuel assemblies in close proximity to one another. The purpose of the neutron absorber materials is to preclude neutronic coupling between adjacent fuel assemblies and to maintain the fuel in a subcritical storage condition. METAMIC neutron absorber has been used in high-density storage racks. But, neutron absorber materials can be subject to severe conditions including long-term exposure to gamma radiation and neutron radiation. Recently, some of them have experienced degradation, such as white spots on the surface. Under these conditions, the material must continue to serve its intended function of absorbing neutrons. For the first time in Korea, this article uses a neutron attenuation test to examine the performance of METAMIC surveillance coupons. Also, scanning electron microscope analysis was carried out to verify the white spots that were detected on the surface of METAMIC. In the neutron attenuation test, there was no significant sign of boron loss in most of the METAMIC coupons, but the coupon with white spots had relatively less B-10 content than the others. In the scanning electron microscope analysis, corrosion material was detected in all METAMIC coupons. Especially, it was confirmed that the coupon with white spots contains much more corrosion material than the others.

The effect of mechanical properties of bone in the mandible, a numerical case study

  • Ramos, Antonio;Marques, Hugo;Mesnard, Michel
    • Advances in biomechanics and applications
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    • 제1권1호
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    • pp.67-76
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    • 2014
  • Bone properties are one of the key components when constructing models that can simulate the mechanical behavior of a mandible. Due to the complexity of the structure, the tooth, ligaments, different bones etc., some simplifications are often considered and bone properties are one of them. The objective of this study is to understand if a simplification of the problem is possible and assess its influence on mandible behavior. A cadaveric toothless mandible was used to build three computational models from CT scan information: a full cortical bone model; a cortical and cancellous bone model, and a model where the Young's modulus was obtained as function of the pixel value in a CT scan. Twelve muscle forces were applied on the mandible. Results showed that although all the models presented the same type of global behavior and proximity in some locations, the influence of cancellous bone can be seen in strain distribution. The different Young's modulus defined by the CT scan gray scale influenced the maximum and minimum strains. For modeling general behavior, a full cortical bone model can be effective. However, when cancellous bone is included, maximum values in thin regions increase the strain distribution. Results revealed that when properties are assigned to the gray scale some peaks could occur which did not represent the real situation.

The Role of the Spatial Externalities of Irrigation on the Ricardian Model of Climate Change: Application to the Southwestern U.S. Counties

  • Bae, Jinwon;Dall'erba, Sandy
    • Asian Journal of Innovation and Policy
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    • 제10권2호
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    • pp.212-235
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    • 2021
  • In spite of the increasing popularity of the Ricardian model for the study of the impact of climate change on agriculture, there has been few attempts to examine the role of interregional spillovers in this framework and all of them rely on geographical proximity-based weighting schemes. We remedy to this gap by focusing on the spatial externalities of surface water flow used for irrigation purposes and demonstrate that farmland value, the usual dependent variable used in the Ricardian framework, is a function of the climate variables experienced locally and in the upstream locations. This novel approach is tested empirically on a spatial panel model estimated across the counties of the Southwest USA over 1997-2012. This region is one of the driest in the country, hence its agriculture relies heavily on irrigated surface water. The results highlight how the weather conditions in upstream counties significantly affect downstream agriculture, thus the actual impact of climate change on agriculture and subsequent adaptation policies cannot overlook the streamflow network anymore.