• Title/Summary/Keyword: Critical parts

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Response of transmission line conductors under different tornadoes

  • Dingyu Yao;Ashraf El Damatty;Nima Ezami
    • Wind and Structures
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    • v.37 no.3
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    • pp.179-189
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    • 2023
  • Multiple studies conducted in the past evaluated the conductor response under one tornado wind field, while the performance of transmission lines under different tornado wind fields still remains unknown. Thus, the objective of this paper is to estimate the variation in the conductor's critical longitudinal and transverse reactions under different tornado wind fields, as well as providing the corresponding critical tornado configurations. The considered full-scale tornadoes are the Spencer, South Dakota, 1998, the Stockton, Kansas, 2005 and the Goshen County, Wyoming, 2009. Computational Fluid Dynamics (CFD) simulations were previously conducted to develop these wind fields. All tornadoes have been rescaled to have a common velocity matching the upper limit of the F2 Fujita scale. Eight conductor systems, each including six spans, are considered in this paper. For each conductor, parametric studies are conducted by varying the location of the three tornado wind fields relative to the tower of interest, therefore the peak reactions associated with each tornado are determined. A semi-analytical closed-form solution, previously developed and validated, is used to calculate the reactions. The study conducted in this paper can be divided into two parts: In the first part, a parametric study considering a wide range of tornado locations is conducted. In the second part, the parametric study focuses on the tornado location leading to the critical tangential velocity on the tower. Based on this extensive parametric study, a critical tornado defined as the Design Tornado and its critical locations, tornado distance R = 125 m, tornado angle 𝜃 = 15° and 30°, are recommended for design purposes.

The anti-hyperglycemic property of different ginseng partitions

  • Xie, Jing-Tian;Wang, Chong-Zhi;Kim, Stephen;Yuan, Chun-Su
    • Advances in Traditional Medicine
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    • v.5 no.1
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    • pp.1-15
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    • 2005
  • Ginseng is a popular medicinal plant highly valued throughout the world. Asian ginseng is one of the most common species of ginseng. It has long occupied a significant position in oriental medicine and has been justified its name as the 'king herb'. As a nutritional supplement, ginseng is an extremely common and popular herbal medicine in the United States and Canada in recent decades. The multiple constituents of ginseng possess equally multifaceted pharmacological actions as demonstrated by numerous studies. Ginseng root and its constituents influenced the central nervous system, endocrine, cardiovascular, gastrointestinal system, sexual, renal organ and immune system, etc. One important action is its anti-hyperglycemic effect. Previous studies on ginseng demonstrate that only the root of ginseng has been used in the treatment of diabetes, while the other parts of ginseng plant were always neglected. Recently, we analyzed the constituents of ginseng berry, leaf and discovered that ginseng berry, leaf extracts and its total ginsenosides have the ability to reduce hyperglycemia and body weight and increase the peripheral glucose utilization in obese or diabetic ob/ob or db/db mice. Our data suggest that all parts of ginseng plant, including root, berry, leaf and stem exhibit potent anti-hyperglycemic and anti-obese effects and may provide an opportunity to develop a novel class of anti-diabetic agents.

Device Design for Inspection Curved Pipes using the Mobile Robot (이동로봇을 이용한 곡관(Curved Pipes) 검사용 디바이스 설계)

  • 조현영;최창환;최용제;김승호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1458-1462
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    • 2003
  • High temperature and high pressure heavy water flows through the pipes in atomic power plants. The curved parts of pipes are critical parts in that they change the direction of steam flow, and these parts are especially affected by severe wear. Therefore, most pipes in atomic power plants are tested by non-destructive examination by workers who use ultrasonic sensors to measure the wall thickness of pipes. But not only are these pipes located in a very dangerous environment, but the space is also very limited. For the safety of workers, it is necessary to design a device that uses a mobile robot that can inspect curved pipes. This paper presents the design and construction of a small device that can generate the necessary contact forces between ultrasonic sensors and pipe walls in a limited space. And a mobile robot is used in place ortho worker for successful non-destructive examination.

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Data Dictionary of Automotive Parts based on PLIB Part 42 (PLIB 파트42를 이용한 자동차부품의 데이터사전)

  • 김영범;조준면;한순흥
    • The Journal of Society for e-Business Studies
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    • v.6 no.2
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    • pp.127-142
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    • 2001
  • For the B2B e-commerce and SCM (Supply Chain Management), standardization of electronic catalogue that contains product and business data is important. Especially, standardization of hierarchies that is required for categorization, and standardization of product properties are difficult and costly to maintain. The ability of searching for items and data in databases is critical for successful e-commerce system. This paper introduces the data dictionary of PUB (ISO 13584) part 42 which can establish the standard of product data. The method is applied to develop the data dictionary of automotive parts.

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Implementation of Shipbuilding components and materials management system (선박부품 자재관리시스템 구축 방안)

  • Park, Doo-jin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.909-910
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    • 2012
  • Shipbuilding is an order made assembly production basically. To build a single vessel, it costs hundreds of thousands small and big parts and million tons of structural steel. From contract to delivery, It takes 2 years of time in general. Shipbuilding parts are supplied order made based in and out of the country. For the cost and efficiency issue, on-time supply of ship parts is critical. Thus, this study suggests the optimum material management system plan of ship components for the best result.

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Method of Shape Error Measurement for the Optimal Blank Design of Shapes with 3D Contour Lines (목표윤곽선이 3 차원 곡선인 형상의 최적블랭크 설계를 위한 형상오차 측정법)

  • Shim, H.B.
    • Transactions of Materials Processing
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    • v.24 no.1
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    • pp.28-36
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    • 2015
  • After a short review of the iterative optimal blank method, a new method of measuring the shape error for stamped parts with 3D contour lines, which is an essential component of the optimal blank design, is proposed. When the contour line of the target shape does not exist in a plane, but exists in 3D space, especially when the shape of the target contour line is very complicated as in the real automotive parts, then the measurement of the shape error is critical. In the current study, a method of shape error measurement based on the minimum distance is suggested as an evolution of the radius vector method. With the proposed method, the optimal blank shapes of real automotive parts were found and compared to the results of the radius vector method. From the current investigation the new method is found to resolve the issues with the radius vector method.

A Study on the Application of Disaster Management System for Business Area (기업에서 재난관리시스템 활용에 관한 연구)

  • Oh, Se-Jung;Kim, Chan-O
    • Journal of the Korean Society of Safety
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    • v.28 no.1
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    • pp.132-136
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    • 2013
  • Even though most of domestic corporations are doing various activities to reduce disasters, it is true that those are actually limited to some parts of business or the formalities in order to obtain specific certificates. For that reason, this writer study a efficient utilization of a guideline about accident provision and business continuity management for less disasters of companies, prevent interruption of critical mission. In short, it is required to operate an effective disaster recovery system and safety management system integrated by a mutual recognition on the relevant parts and different parts. And there is a need to establish a integrated recovery center in order to manage disaster recovery system realistic and effective.

A Product Data Model for the Integration Module for Supporting Collaborations on Hardware and Software Development (소프트웨어 하드웨어 협동설계를 위한 통합모듈을 지원하는 제품자료모델)

  • Do, Namchul
    • Journal of Information Technology Services
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    • v.11 no.4
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    • pp.171-180
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    • 2012
  • Since software and hardware integration has became a strategic tool for companies to innovate their products, an information system that can comprehensively manage software and hardware integrated product development is critical for the current product development. This paper proposed a product data model that can support modules of related software and hardware parts in Product Data Management(PDM) integrated with Software Configuration Management(SCM). The model allows engineers to define software and hardware product structure independently, and support the integration module that can summon related software and hardware parts to build a comprehensive module for collaboration. Through the integration module, engineers can identify and examine the effectiveness of their design alternatives to other related parts form different disciplines. The product data model was implemented as a prototype PDM system and tested with an example robotics product.

A Concept Analysis of Hardiness (강인성 (Hardiness)의 개념 분석)

  • 이영애
    • Journal of Korean Academy of Nursing
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    • v.24 no.4
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    • pp.616-622
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    • 1994
  • Precise concept analysis has been neglected be-cause of a lack of understanding of its necessity and a lack of conceptual analytic knowledge. Concept analysis is the mental work of examining parts, phenomenon and the interrelated whole of a thing. Focus in this article is to extract the critical attributes of hardiness and make an operational delinition. The process of concept analysis is illustrated and documented using the analytic approach described by Walker and Avant (1983). To explore the explicit or implicit meanings of hardiness, existing literature was reviewed. The evolution of hardiness and the dictionary definitions were also added. Hardiness can be defined as follows : A condition of being inured to fatigue or hardship which has three subcomponents-challenge, control and commitment. Critical attributes of hardiness were extracted that may be used in naming the occurrence of the phenomenon. Model case, contrary case, borderline case and related case were described. Antecedents and consequences were explored. The defining critical attributes of hardiness are : 1. Resistance-hardiness involves resistance of stress or hardship. 2. Hardiness involves appraisal of change as a chance. 3. Hardiness implies interpretation of events and self as influential,. 4. Hardiness requires active involving reaction Implications for nursing and for further study are added.

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Dynamic Characteristics Analysis for the Online Monitoring System Designing KTX MRU and Improvement of the Stability Related Variable High Speed (고속열차 감속기의 상시감시시스템 설계 및 가변속주행시 안정성 향상을 위한 동특성해석)

  • Park, Byung Su;Kim, Jin Woo;Choi, Sang Rak;Song, Young Chun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.4
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    • pp.301-307
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    • 2013
  • MRU(motor reduction unit) for KTX is a assembled complex structure that is equipped with a lot of parts at the express train KTX and that is the core power source operating variable speeds. This study is recorded the dynamic characteristics analysis results tested by EMA which is done through the parts and assembly test, transient analysis and stoped train test in order to design the online monitoring system for KTX MRU. And the mode shapes result from critical vibration frequency explain the relation with variable speeds of express train over 250 km/hr. Also these variable speeds make variable operational frequencies at pinion, axle gear mesh frequency and normal bearing fault frequencies. As the specified speed can make resonance with natural frequencies of the MRU, for the train operating stability, this study also presents the MRU's critical speeds calculated by the each train speed.