• Title/Summary/Keyword: Adequate level

Search Result 1,129, Processing Time 0.026 seconds

A Study of De-electrification Characteristics of Charged Body By Soft X-Ray Ionizer (연X선 Ionizer에 의한 대전물체의 제전특성에 관한 연구)

  • 이동훈
    • Journal of the Korean Society of Safety
    • /
    • v.13 no.3
    • /
    • pp.67-73
    • /
    • 1998
  • The technology for neutralizing static electricity by soft X-ray radiation has been newly developed. This technology involves ionization of gas molecules in the vicinity of a charged substrate to generate ions and electrons to reduce electrostatic potential. The ULSI device substrate and liquid crystal display substrate tend to get charged instantly to a high potential level when they are handled in the manufacturing process. Soft X-ray radiation is adequate in air or $O_2$ gas at atmospheric pressure. This newly developed neutralization method is effective to be superior to the conventional technique, i.e., an ionizer by using corona discharge ,in every aspect. The new method features excellent neutralization capability and is able to completely reduce electrostatic potential to 0 V within a short time. Moreover, this is a very clean antistatic technology free from particle generation ,ozone generation, and electromagnetic noise, which are problems in using the corona discharge ionizer.

  • PDF

General Cytological Characters of Malignant Breast Lesions (유방의 세침흡인 세포검사 -악성 병변의 일반적인 세포 소견-)

  • Kim, Jee-Yeon
    • The Korean Journal of Cytopathology
    • /
    • v.18 no.2
    • /
    • pp.100-111
    • /
    • 2007
  • Fine needle aspiration (FNA) cytology of breast disease is recognized to be highly accurate and cost effective, especially when this is used in combination with clinical examination and imaging as part of a triple approach. A probabilistic/categorical approach is used for the classification of breast FNA specimens. Criteria are defined from the perspective of the likelihood of making a definitive diagnosis of cancer on excision. This approach is an accurate way of classifying breast FNA specimens, and this can be reliably applied regardless of the level of experience of the pathologist for interpreting the case. When a definitive diagnosis of malignancy is made, the next step is to determining the specific histologic types of the malignancy according to their cytological features. In order to make an accurate diagnosis of carcinoma and for correct typing a tumor, an adequate, correctly sampled aspirate without any other artifacts is required.

A compare study on the Evaluation Method of Aircraft Noise (항공기 소음의 평가 척도에 대한 비교 연구)

  • 전지현;안병옥;송민정;장길수;김선우
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2001.11b
    • /
    • pp.703-706
    • /
    • 2001
  • Currently domestic criteria for the aircraft noise is being adapted WECPNL(weighted equivalent continuous perceived noise level), while internationally preferred method is which is originated from $L_{eq}$ and can evaluate even environmental noise. WECPNL used in domestic as a evaluation method is only for the aircraft noise. It is, therefore, not adequate for the evaluation of residents' injury, moreover, it is very difficult to measure the aircraft noise with WECPNL due to the complicated calculating procedures as long as automatic measuring system is not used. Accordingly, this study aims to propose alternative evaluation method for the aircraft noise. To achieve this purpose, the data measured by automatic measuring system were gathered and calculated with three evaluation methods: WECPNL, $L_{eq}$ and $L_{dn}$ and the results calculated from different methods were compared and analyzed.

  • PDF

Seismic Performance Evaluation for MCR of Nuclear Power Plant Isolated by FPS (FPS로 면진된 원전 주제어실의 내진 성능 평가)

  • 김대곤;김우범;서용표;문대식;김종엽
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2003.09a
    • /
    • pp.453-460
    • /
    • 2003
  • The objective of this study is to investigate the seismic performance for a seismically isolated main control room (MCR) of nuclear power plant. MCR was isolated by spherically shaped friction pendulum system (FPS). The FPS provided the simplest means of achieving long period in the isolation system under low gravity load. Some parametric studies were conducted with different properties of FPS. When the coefficient of friction in the sliding surface of FPS is low, the seismic performance of MCR was satisfactory However, the lateral displacement in the isolation level was rather large. To restrict this displacement into adequate range, a fluid viscous dampers were used.

  • PDF

A substructure formulation for the earthquake -induced nonlinear structural pounding problem

  • Shi, Jianye;Bamer, Franz;Markert, Bernd
    • Earthquakes and Structures
    • /
    • v.17 no.1
    • /
    • pp.101-113
    • /
    • 2019
  • Earthquake-induced pounding is one of the major reasons for structural failure in earthquake prone cities. An accurate description of the pounding phenomenon of two buildings requires the consideration of systems with a large number of degrees of freedom including adequate contact impact formulations. In this paper, firstly, a node to surface formulation for the realization of state-of-the-art pounding models for structural beam elements is presented. Secondly, a hierarchical substructure technique is introduced, which is adapted to the structural pounding problem. The numerical accuracy and efficiency of the method, especially for the contact forces, are verified on an academic example, applying four different impact elements. Error estimations are carried out and compared with the classical modal truncation method. It is demonstrated that the hierarchical substructure method is indeed able to significantly speed up the numeric integration procedure by preserving a required level of accuracy.

An Analysis of the Dynamic Characteristics of a Spool Type Pressure Control Valve (스풀형 압력제어밸브의 동특성 해석)

  • Moon, Kang Hyun;Huh, Jun Young
    • Journal of Drive and Control
    • /
    • v.15 no.4
    • /
    • pp.61-66
    • /
    • 2018
  • Almost every hydraulic system is equipped with a pressure relief valve, to maintain working pressure of the system at a pre-determined level. Thus, dynamic characteristics of such a relief valve, in conjunction with other hydraulic components, are important in designing the hydraulic control system. The single stage pressure relief valve is dynamically undesirable, due to relatively low viscous damping, that causes high frequency oscillations. This problem is overcome by introducing orifices in the inner pilot line, and drain line. In this study, for the single stage spool type pressure relief valve, the system equations were derived through an adequate linearisation and several simplifications were made, to use the transfer function formulation technique. All coefficients were evaluated and used, to make some results by using Matlab software. Results of analysis are compared with experimental results. In this study, parameters affecting stability of valve design are determined and suggested relative to the design.

Do the Technostress Creators Predict Job Satisfaction and Teacher Efficacy of Primary School Teachers in Korea?

  • LEE, Mignon;LIM, Kyu Yon
    • Educational Technology International
    • /
    • v.21 no.1
    • /
    • pp.69-95
    • /
    • 2020
  • The purpose of this research is to analyze the predictive powers of the five technostress creators - techno-overload, techno-invasion, techno-complexity, techno-insecurity, and techno-uncertainty - in job satisfaction and teacher efficacy of primary school teachers in Korea when they incorporated mobile technology into teaching. A questionnaire was designed to measure the level of teacher's stress from technology, job satisfaction and teacher efficacy. Data were collected from 164 teachers. Multiple regression analysis was conducted to explain which area of technostress led to varying degrees of job satisfaction and teacher efficacy. The results showed that techno-complexity alone predicted both job satisfaction and teacher efficacy. The reason why techno-complexity was the only predictor is that teachers would have first needed to understand how to incorporate mobile technology into teaching, before feeling overloaded, invaded, insecure, or uncertain about it, meaning techno-complexity precedes other constructs. Therefore, the only stress factor that affected them was how to understand the complexity of mobile technology. This calls for adequate training and support from schools and governments in order for the teachers to fully incorporate technology into teaching.

The Main Problems of Forming Soft Skills in the Future Career of a Student in a Pandemic

  • Zhukova, Oksana;Mandragelia, Volodymyr;Veselska, Liudmila;Yermolenko, Andrii;Dotsenko, Svitlana
    • International Journal of Computer Science & Network Security
    • /
    • v.22 no.3
    • /
    • pp.23-28
    • /
    • 2022
  • The purpose of the article is to analyze students' self-assessment of the level of soft skills development and the prospects for its improvement in a pandemic. For an adequate and objective study of the stated issues, comparative analysis was most often used. For this purpose, theoretical studies of national and foreign experts were analyzed, which included specific sociological surveys. Prospects for further work are assumed in a detailed study of the factors, conditions and mechanisms for the formation and development of soft skills in students of natural, engineering and technological, medical, social and humanitarian specialties.

Knowledge Sharing Among School Library Personnel in Nigeria: How Do Digital and Media Literacies Interfere?

  • Aramide, Kolawole Akinjide
    • International Journal of Knowledge Content Development & Technology
    • /
    • v.12 no.2
    • /
    • pp.7-27
    • /
    • 2022
  • The study investigated the contributions of digital and media literacies to knowledge sharing among school library personnel in Nigeria. The survey research design was adopted for the study while a questionnaire was used to collect data from the 190 respondents that constitute the sample size for the study. Findings from the study revealed a high level of digital and media literacy skills possessed by the school library personnel surveyed. Producing information, evaluating digital information, and finding digital were major media and digital information literacy skills that significantly contributed to knowledge sharing among the school library personnel. The study recommended that adequate attention should be given to the development of digital and media literacies of school library personnel in Nigeria to ensure effective and efficient knowledge sharing.

The Methods of Value Management to Support Decision-Making of Urban Regeneration Projects

  • Kang, Hyun-Koo;Yu, Jung-Ho;Kim, Chang-Duk;Son, Bo-Sik
    • International conference on construction engineering and project management
    • /
    • 2009.05a
    • /
    • pp.1503-1508
    • /
    • 2009
  • The paradigm of urban generation does not lie in physical development/maintenance such as urban redevelopment any more. The paradigm is shifting to balanced activation of administration / management functions including central commerce/business functions, broad culture/tourism functions, international functions and adequate level of residence functions. The urban regeneration project aims to restore functions of cities by physical/environmental, living/cultural and industrial/economical regeneration and is managed differently from existing projects in that it includes multiple sub-projects in it. The overall projects management should be by managing the value sought by the urban regeneration project and multiple other sub-projects. The objective of this study is to present various methods of value management in order to avoid conflicts between various objectives within the said project. It aims to provide the value management methods for decision making by understanding correlatedness between values of various projects and prioritizing them.

  • PDF