• Title/Summary/Keyword: Internal and External Evaluation

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Colorectal Cancer Staging Using Three Clustering Methods Based on Preoperative Clinical Findings

  • Pourahmad, Saeedeh;Pourhashemi, Soudabeh;Mohammadianpanah, Mohammad
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.2
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    • pp.823-827
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    • 2016
  • Determination of the colorectal cancer stage is possible only after surgery based on pathology results. However, sometimes this may prove impossible. The aim of the present study was to determine colorectal cancer stage using three clustering methods based on preoperative clinical findings. All patients referred to the Colorectal Research Center of Shiraz University of Medical Sciences for colorectal cancer surgery during 2006 to 2014 were enrolled in the study. Accordingly, 117 cases participated. Three clustering algorithms were utilized including k-means, hierarchical and fuzzy c-means clustering methods. External validity measures such as sensitivity, specificity and accuracy were used for evaluation of the methods. The results revealed maximum accuracy and sensitivity values for the hierarchical and a maximum specificity value for the fuzzy c-means clustering methods. Furthermore, according to the internal validity measures for the present data set, the optimal number of clusters was two (silhouette coefficient) and the fuzzy c-means algorithm was more appropriate than the k-means clustering approach by increasing the number of clusters.

Network Traffic-Based Access Control Using Software-Defined Perimeter (소프트웨어 정의 경계를 이용한 네트워크 트래픽 기반 동적 접근 제어)

  • Seo-Yi Kim;Il-Gu Lee
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.34 no.4
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    • pp.735-746
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    • 2024
  • The rapid advancement of computer technology has necessitated a safer user environment, prompting the adoption of the zero trust model, which verifies all internal and external network activities. This paper proposes an efficient network traffic data-based dynamic access control method leveraging Software-Defined Perimeter (SDP) capabilities to implement zero trust and address latency issues. According to the performance evaluation results, the detection performance of the proposed scheme is similar to that of conventional schemes, but the dataset size was reduced by 62.47%. Additionally, by proposing an adaptive zero trust verification approach, the dataset size and verification time were reduced by 83.9% and 9.1%, respectively, while maintaining similar detection performance to conventional methods.

Radiographic Evaluation of Femoral Tunnel Placement During ACL Reconstruction (전방 십자 인대 재건술시 대퇴 터널의 위치에 대한 방사선학적 평가)

  • Chung, Hyun Kee;Choi, Choong Hyeok;Lee, Joong Hak
    • Journal of the Korean Arthroscopy Society
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    • v.2 no.1
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    • pp.80-84
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    • 1998
  • The isometric position for the graft is important in the anterior cruciate ligament reconstruction surgery. It is well known that the femoral position is more critical than tibial side. But, there is few deciding method of proper graft position after the anterior cruciate ligament reconstruction surgery. So we planned to evaluate the ideal femoral isometric position with 6 adult cadavaric femurs and exact radiographs. After the insertion of femoral interference screw on ideal isometric position, we obtained roentgenograms of true lateral view and 10, 20, 30, 45 degree internal and external rotation views. Then we measured the shortest distance from the posterior cortical margin of lateral femoral condyle to posterior border of interference screw on the radiographs. We also measured true distance between posterior cortical margin of lateral femoral condyle to the posterior margin of femoral tunnel after cutting of distal femur. Based on this study, we could not determine the permissible rotation degree of radiographs. But we concluded that if the distance between posterior cortical margin of lateral femoral condyle and posterior border of interference screw ranges 4.5-6.5mm on the lateral view, the femoral position is considered as a relatively ideal isometric good position.

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Development of a Numerical Model for Evaluation of Long-Term Mechanical Degradation of Shotcrete Lining in Tunnels (터널 숏크리트 라이닝의 장기 내구성 저하 평가를 위한 수치모델의 개발)

  • Shin Hyu-Soung;Lim Jong-Jin;Kim Dong-Gyu;Lee Gyu-Phil;Bae Gyu-Jin
    • 한국터널공학회:학술대회논문집
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    • 2005.04a
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    • pp.251-258
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    • 2005
  • In this study, a new concept for simulating a long-term mechanical degradation mechanism of shotcrete in tunnels has been proposed. In fact, it is known that the degradation takes place mainly by internal cracks and reduced stiffness, which results mainly from volume expansion of shotcrete and corrosion of cement materials, respectively. This degradation mechanism of shotcrete in tunnels appears similar to those of the most kinds of chemical reactions in tunnels. Therefore, the mechanical degradation induced by a kinds of chemical reaction was generalized and mathematically formulated in the framework of thermodynamics. The numerical model was implemented to a 3D finite element code, which can be used to simulate behaviour of shotcrete structures undergoing external forces as well as chemical degradation in time. A number of illustrative examples were given to show the feasibility of the model in tunnel designs with consideration of long-term degradation effect of shotcrete quantitatively for increase of long-term safety of tunnels.

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Evaluation Absorbed Dose During the Breast Cancer Brachytherapy in Canine Phantom (반려견 팬텀에서 유방암 근접방사선치료 시 흡수선량 평가)

  • Kim, Jung-Hoon;Lee, Deuk-Hee
    • Journal of the Korean Society of Radiology
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    • v.14 no.5
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    • pp.523-528
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    • 2020
  • The application of breast cancer, which has the highest incidence in females among cancer that is the number one cause of death for dogs, was to be evaluated the absorbed dose during brachytherapy using simulation. MCNPX program was used for simulation, and a small size canine phantom was produced to measure absorbed dose. The results of the absorbed dose was the highest at 192Ir to 1.02E-12 Gy/# for tumors, and the same tendency was shown for internal and external absorbed dose. Therefore, the selection of appropriate sources for dog breast cancer should be considered in brachytherapy, taking into account dog breeds and exposures.

Study on Thermal Conductive PV(PhotoVoltaic) Backsheet using MgO Masterbatch with High Thermal Conductivity (고열전도도 MgO를 이용한 열전도성 PV(PhotoVoltaic) 백시트의 연구)

  • Kim, Chang-Hee;Jang, Hyun-Tae;Park, Jong-Se;Yoon, Jong-Kuk;Noh, Eun-Seob;Park, Ji-Soo;Koo, Kyung-Wan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.3
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    • pp.448-453
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    • 2018
  • PV module protective film plays an important role in protecting the solar cell from external environment by anti-hydrolysis polyester, UV resistance and mechanical properties. The backsheet was manufactured by using Roll-to-Roll dry laminating process. The backsheet structure is composed of 3 layers, which are PE, PET, and Fluorine polymer films. In this study, we have experimented the variation of thermal conductivities depending on MgO inputs 10% to 25% in order to confirm the dependence of the module efficiencies. High thermal conductive backsheet can increase the module output power efficiency because the heat is dissipated by spreading out the internal heat. Long-term environment weatherability tests were conducted for confirming 25 year reliability in the field such as PCT, UV, and power efficiency degradations. As the evaluation result, high thermal conductivity can be effective for increase of power efficiency of solar panel by using thermal conductive MgO masterbatch.

Experiment and Evaluation of Mist Diffusion from Water Tube for Blasting Dust Control in accordance with the Explosives Position (폭약 기폭위치에 따른 발파 분진제어용 워터튜브 주입수의 분무확산 실험 및 평가)

  • Yang, Hyung-Sik;Ko, Young-Hun;Kim, Jung-Gyu;Noh, You-Song;Park, Hoon;Cho, Sang-Ho
    • Tunnel and Underground Space
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    • v.25 no.1
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    • pp.46-55
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    • 2015
  • A water tube with detonating cord was devised to control the blast dust. Water diffusion experiments with different detonating cord positions were conducted during the series of experiments to optimize the design parameters of the tube. Images from high speed camera were analyzed to evaluate the results. AUTODYN program was adopted to simulate the diffusion process of water and compared with the images. Diffusion of water shows cross flow in case of external charge while the internal case shows radial flow. A bubble ring was formed during the numerical analysis of internal charge case as occurred in underwater blast. An additional bubble ring was formed by the reflection pressure from the ground. And the Weber number was determined as sufficient for spray atomization performance of the water tube.

Development of Triaxial Cells Operable with In Situ X-ray CT for Hydro-Mechanical Laboratory Testing of Rocks (원위치 X-ray CT 촬영이 가능한 암석의 수리-역학 실험용 삼축셀 개발)

  • Zhuang, Li;Yeom, Sun;Shin, Hyu-Soung
    • Journal of the Korean Geotechnical Society
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    • v.36 no.9
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    • pp.45-55
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    • 2020
  • X-ray computed tomography (CT) is very useful for the quantitative evaluation of internal structures, particularly defects in rock samples, such as pores and fractures. In situ CT allows 3D imaging of a sample subjected to various external treatments such as loading and therefore enables observation of changes that occur during the loading process. We reviewed state-of-the-art of in situ CT applications for geomaterials. Two triaxial cells made using relatively low density but high strength materials were developed aimed at in situ CT scanning during hydro-mechanical laboratory testing of rocks. Preliminary results for in situ CT imaging of granite and sandstone samples with diameters ranging from 25 mm to 50 mm show a resolution range of 34~105 ㎛ per pixel pitch, indicating the feasibility of in situ CT observations for internal structural changes in rocks at the micrometer scale. Potassium iodide solution was found to improve the image contrast, and can be used as an injection fluid for hydro-mechanical testing combined with in situ CT scanning.

A study on an evaluation model for industrial information systems by industry sectors (업종별 특성을 고려한 기업정보화 성숙모형)

  • 진경수;임춘성;박찬권
    • Proceedings of the CALSEC Conference
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    • 2002.01a
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    • pp.86-106
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    • 2002
  • Informatization is a process that corporation's external environmental factors and internal environmental factors influence as complex. is a phenomenon that appears via this process. To evaluate that informatization was propeled well or informatization level is high can be dangerous work extremely by only once-over-lightly some factors, organization information ability is superior or infrastructure is constructed well. Therefore, an evaluation for industrial information systems that consider corporation's external environment and internal environment configurationally and objective estimation through this is required in national dimension. This research sorted types of business using types of business classification of 2001 EIII(Evaluation Indices of Industrial Informatization) laying stress on corporation's product and product production process for reflecting various industrial classification. And we are dividing whole our country corporations by manufacture industry, the construction industry, distribution industry, service industry, banking industry 5 types of business. To see such classed types industry classification from consistent viewpoint, we saw them within new framework, purchase, operation, physical distribution, marketing and sale. service etc. laying stress on primary businesses except support businesses of planning, financial management etc. To draw special quality of business center from primary business of each types of business, we draw industry classification Key Capability that centers when plans corporation's corporate strategy and information strategy. And we deducted industrial classification key production business connected with industry classification Key Capability. After drawing an evaluation items for industrial information systems in informatization analysis viewpoint laying stress on drawn businesses. Finally we did Case Study by making out an evaluation for industrial information systems questionnaire that considers special quality of manufacturing industry. Through EIII that consider the industrial classification, we could know that it explains the corporation's purchase, production, distribution in general and detail.

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An Inverse Boundary Element Method for Finding Boundary Tractions of an Elastic Body (탄성체의 경계 하중을 구하기 위한 역경계요소법)

  • Lee, Sang-Hoon;Kim, Hyun-Gyu
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.3
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    • pp.223-229
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    • 2009
  • Most of structural analyses are concerned with the deformation and stress in a body subjected to external loads. In many fields, however, the interpretation of inverse problems is needed to determine surface tractions or internal stresses from measured displacements. In this study, the inverse processes by using the boundary element method are formulated for the evaluation of boundary tractions from displacements measured on a remote surface. Small errors in measured displacements often result in a substantial loss of accuracy of an inverse system. Numerical results show that the error in reconstructed tractions by using the inverse boundary element methods is sensitive to measurement location and noise.