• 제목/요약/키워드: Operating environment

검색결과 2,892건 처리시간 0.031초

고도처리 하수처리장 운전조건의 통계분석 (Statistical Analysis of Operating Parameters on Advanced Wastewater Treatment Plant)

  • 이찬형;문경숙
    • 한국환경과학회지
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    • 제14권2호
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    • pp.251-258
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    • 2005
  • Statistical analysis between operating parameters and effluent quality on advanced wastewater treatment plant was performed. Through factor analysis four factors derived varimax rotation were selected each plant. Four components explained $80\%,\;82\%$ of the total variance of the process, respectively. The components on MLE plant were identified in the following order: 1) HRT increase and BOD load decrease by influent decrease, 2) Biomass, 3) SVI increase by internal return increase, 4) Microbial diversity by SRT increase. On $A_2O$ plant, we defined them as follows: factor 1, high MLSS by return rate increase, HRT increase by influent decrease; factor 2, biomass; factor 3, BOD of influent; factor 4 was relate to DO.

Load spectra growth modelling and extrapolation with REBMIX

  • Volk, Matej;Fajdiga, Matija;Nagode, Marko
    • Structural Engineering and Mechanics
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    • 제33권5호
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    • pp.589-604
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    • 2009
  • In the field of predicting structural safety and reliability the operating conditions play an essential role. Since the time and cost limitations are a significant factors in engineering it is important to predict the future operating conditions as close to the actual state as possible from small amount of available data. Because of the randomness of the environment the shape of measured load spectra can vary considerably and therefore simple distribution functions are frequently not sufficient for their modelling. Thus mixed distribution functions have to be used. In general their major weakness is the complicated calculation of unknown parameters. The scope of the paper is to investigate the load spectra growth for actual operating conditions and to investigate the modelling and extrapolation of load spectra with algorithm for mixed distribution estimation, REBMIX. The data obtained from the measurements of wheel forces and the braking moment on proving ground is used to generate load spectra.

운행지형형태에 따른 2$\frac{1}{2}$톤 트럭의 수명비교 (Life Comparision of 2$\frac{1}{2}$ Ton Truck Considering The Operation Terrains)

  • 김장현;하석태
    • 한국국방경영분석학회지
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    • 제16권2호
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    • pp.1-13
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    • 1990
  • The life of an equipment depends upon its operating characteristics and physical environment factors. This paper presents the economic life length of 2 1/2 ton truck considering the operation terrains. For this specific research, the operation terrains are categorized into seacoast area, mountain area and plain area. To compute the life length, the method of equivalent annual cost is employed. The sample vehicles from each corresponding area are randomly selected from those vehicles whose ages exceed 9 years. This research finds the following results : (1) The life length operated at seacoast area is 9.75 years, (2) The life length operated at mountain area is 11.25 years, (3) The life length operated at plain area is 14 years. This research argues that the key factor such as characteristics of operating enviroment for allocation of operating and maintaining cost should be considered.

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Thermal Stress Analysis on the Solid Oxide Fuel Cell according to Operating Temperature

  • Kwon, Oh-Heon;Kang, Ji-Woong;Jo, Se-Jin
    • International Journal of Safety
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    • 제10권1호
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    • pp.1-4
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    • 2011
  • The fuel cell is one of the green energy receiving a lot of attention. Among the fuel cells, it is generally referred to SOFC(solid oxide fuel cell) which is made up composites of a solid. SOFC has excellent merits in the side of environment and energy. However because of the high operating temperature, it has economic loss by the using of expensive materials and problems of structural instability by thermal stresses. Therefore, this study aims to the effect of analysis by the FEMLAB. The results have deformations and the maximum stresses from the variation of the thickness of vulnerability spots. The deformation shows expansion as 0.82% and the stress ${\sigma}_{xx}$ is 392MPa in electrolyte and -56.31MPa in anode. When increasing or decreasing the thickness to 50% of the reference thickness about the electrolyte which is vulnerable spots.

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이동형 머니퓰레이터의 숫자버튼 조작을 위한 시각제어 시스템 개발 (Development of a Visual Servo System in a Mobile Manipulator for Operating Numeral Buttons)

  • 박민규;이민철;주원동
    • 한국정밀공학회지
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    • 제21권7호
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    • pp.92-100
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    • 2004
  • A service robot is expected to be useful in indoor environment such as a hotel, a hospital and so on. However, many service robots are driven by wheels so that they cannot climb stairs to move to other floors. If the robot cannot use elevators. In this paper, the mobile manipulator system was developed, which can operate numeral buttons on the operating panel in the elevator. To perform this task, the robot is composed of an image recognition module, an ultrasonic sensor module and a manipulator. The robot can recognize numeral buttons and an end-effector in manipulator by the vision system. The Learning vector quantization (LVQ) algorithm is used to recognize the number on the button. The barcode mark on the end-effector is used to recognize the end-effector. The manipulator can push numeral buttons using informations captured by the vision system. The proposed method is evaluated by experiments.

플래시 변환 계층을 위한 DPW-LRU 캐시 교체 알고리즘 분석 및 개선 (Analysis and Improvement of the DPW-LRU Cache Replacement Algorithm for Flash Translation Layer)

  • 이형봉;정태윤
    • 대한임베디드공학회논문지
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    • 제15권6호
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    • pp.289-297
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    • 2020
  • Although flash disks are being used widely instead of hard disks, it is difficult to optimize for effective utilization of flash disks because overwrite in place is impossible and the power consumption and time required for read, write, and erase operations are all different. One of these optimization issues is a cache management strategy to minimize write operations. The cache operates at two levels: an operating system equipped with flash disks and a translation layer within the flash disk. Most studies deal with the operating system-level cache strategy. In this study, we implement and analyse the DPW-LRU algorithm which is one of the recently proposed operating system cache replacement algorithms to apply to FTL, and grope with some improvements. As a result of the experiment, the DPW-LRU algorithm maintained superiority even in the FTL environment, and showed better performance with a slight improvement.

웹 기반 운영체제에 관한 연구 (A Study on Web-based operating system)

  • 배유미;정성재;장래영;박정수;소우영
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2012년도 춘계학술대회
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    • pp.674-677
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    • 2012
  • 운영체제는 컴퓨터 하드웨어와 컴퓨터 사용자간의 매개체 역할을 수행하는 것으로 사용자가 프로그램을 수행할 수 있는 환경을 제공한다. 따라서, 운영체제의 주된 목적은 컴퓨터를 편리하게 이용하는 것에 있고, 컴퓨터 하드웨어를 효율적으로 관리하는 데 있다. 컴퓨터를 이용하는 계층의 대중화, 하드웨어의 성능적 향상, 인터넷의 등장, 무선 네트워크의 활성화, 스마트폰 및 태블릿(Tablet) PC 등장, 가상화 기술 및 클라우드 컴퓨팅 등장 등은 운영체제 분야에도 변화를 주기 시작하였다. 특히 서버 가상화 기술을 기반으로 하는 클라우드 컴퓨팅 환경과 다양한 유무선기기를 활용한 인터넷 접속환경으로 인해 웹 기반 운영체제가 탄생하였다. 본 논문에서는 웹 기반 운영체제의 정의, 종류와 특징, 장단점에 대해 분석하고, 앞으로의 전망에 대해 알아본다.

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수술실 간호사의 혈액매개감염 관련 지식, 위험지각과 감염예방행위 (Perception on and Behaviors for Blood-Borne Infection Prevention among Operating Room Nurses)

  • 김남이;정선영
    • 임상간호연구
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    • 제22권3호
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    • pp.276-284
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    • 2016
  • Purpose: The purpose of this study was to identify the factors related to blood-borne infection prevention behaviors based on the risk perception of the health belief model among operating room nurses. Risk perception factors included perceived susceptibility, barriers, benefits, and perceived severity. Methods: Data were collected from 121 operating room nurses working in four different hospitals in Daejeon and Seoul from June 30 to May 11, 2016. Results: The mean age was 31.2 years, and the average years of clinical experience in operating room was 7.9 years. The mean score of knowledge was 13.15. The mean score of perceived susceptibility, barrier, benefit, and perceived severity were 3.76, 3.70, 3.95, and 4.64, respectively. Blood-borne infection prevention behaviors had positive correlation with perceived benefits (p=.010), but negative correlation with sensitivity (p=.009) and barrier (p=.012). The hierarchical regression model on infection prevention behavior was statistically significant (F=4.85, p<.001). The sixteen percent of variance in behavior was explained by age (${\beta}=.18$, p=.038), perceived benefit (${\beta}=.20$, p=.030), perceived susceptibility (${\beta}=-.25$, p=.005), and perceived barrier (${\beta}=-.18$, p=.042). Conclusion: In order to increase infection prevention behaviors among operating room nurses, there is a need for developing specific education program focusing on appropriate management of equipment, instruments, and environment in operating room. In addition, support from the hospital organization level need to be provided as well.

SDR 시스템의 운용소프트웨어 품질평가에 관한 연구 (A Study of Quality Evaluation for SDR System Operating Software)

  • 김민수;이건준;하성재;조상영
    • 한국지능시스템학회논문지
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    • 제24권6호
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    • pp.657-664
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    • 2014
  • 본 논문은 SDR(Software-Defined Radio) 송수신기의 운용 소프트웨어 품질평가를 위한 평가 척도를 제시하고 평가를 자동화할 수 있는 평가 소프트웨어 개발에 대해 설명한다. SDR 운용 소프트웨어는 하드웨어에 종속적인 동작을 하기 때문에 이에 맞는 평가 척도를 도출하기 위하여 동작 환경 및 운영 분야와 동작 방식에 근거한 품질평가 요구사항을 추출하였다. 도출된 평가 척도를 이용한 품질평가의 자동화를 위하여 평가 소프트웨어를 C#언어와 MySQL 데이터베이스를 이용하여 개발하였다. 평가 소프트웨어는 데이터베이스를 이용하여 평가 요소를 입력 또는 갱신할 수 있으며 스크립트를 이용한 자동 평가 기능이 있으며 평가 결과의 시각적 표현이 가능하도록 개발되었다. 도출된 평가 척도와 평가 소프트웨어를 사용하여 파악된 소프트웨어 품질 향상을 위한 개선점은 고품질 SDR 운용 소프트웨어 개발에 유용하게 사용되고 있다.

수술실 간호사의 환자안전문화에 대한 인식이 안전간호활동에 미치는 영향 (The Influences of the Awareness of Patient Safety Culture on Safety Care Activities among Operating Room Nurses)

  • 이경희;이영신;박해경;류정옥;변인승
    • 임상간호연구
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    • 제17권2호
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    • pp.204-214
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    • 2011
  • Purpose: This study was aimed to provide information on the awareness of patient safety culture and safety care activities among operating room (OR) nurses and to analyze the factors influencing the safety care activities. Methods: For this descriptive research, self-reported questionnaires were administered to 168 OR nurses who were working at the university-affiliated and general hospitals. The collected data were analyzed using descriptive statistics, t-test, ANOVA, $Scheff{\grave{e}}$ test, Pearson's correlation coefficient and Stepwise multiple regression with SPSS/WIN 17.0. Results: The mean score of the awareness on patient safety culture was 3.27 out of 5 points and that of safety care activity was 4.31 out of 5. The statistically significant difference was found between experience of safety education and the awareness on patient safety culture. Also, the scores of safety care activities were significantly different according to OR nurses' position, education levels, and experience of safety education. There was a positive correlation between the awareness of patient safety culture and safety care activity. Their explanatory power on safety care activity was 8.8%, which includes working environment in operating room 3.3% and nursing position 5.5%. Conclusion: Compared to the level of patient safety activities, the OR nurses' awareness on patient safety culture was low. Given the specific characteristics and conditions in each hospital, it needs to increase the OR nurses' awareness on patient safety culture and activities related to patient safety.