• Title/Summary/Keyword: Performance Standard

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Development of Standard Resistor Divider for Full Lightning Impulse Voltage (전파 뇌충격전압 측정용 표준 저항분압기의 개발)

  • Kim, Ik-Soo;Moon, In-Wook;Kim, Min-Kyu;Kim, Yung-Bae;Kim, Jin-Gi;Lee, Hyeong-Ho
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1633-1635
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    • 1994
  • This paper presents the development technology of standard resistor divider for full lightning impulse voltage. The ability of high voltage bulk power equipment to withstand lighting stroke is usually evaluated by means of full lightning impulse voltage. Lightning impulse voltage test has been essential to evaluate the insulation performance of electrical power apparatus. Recently International standard (IEC 60) on high voltage measurement techniques is being revised and requests a formal traceability of high voltage measurements. Therefore, general interest for this area has grown considerably during last years, and several international intercomparisions have been completed already worldwide, i.e. Europe, Japan, America etc.. In this viewpoint, we have also investigated the standard resistor divider with shield, which satisfies the IEC recommendation.

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A Study for Robustness of Objective Function and Constraints in Robust Design Optimization

  • Lee Tae-Won
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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    • pp.1662-1669
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    • 2006
  • Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

Design of Quantization Tables and Huffman Tables for JPEG Compression of Medical Images (의료영상의 JPEG 압축을 위한 양자화 테이블과 허프만 테이블 설계)

  • 양시령;정제창;박상규
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.6
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    • pp.453-456
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    • 2004
  • Due to the bandwidth and storage limitations medical images are needed to be compressed before transmission and storage. DICOM (Digital Imaging and Communications in Medicine) specification, which is the medical images standard, provides a mechanism for supporting the use of JPEG still image compression standard. In this paper, we explain a method for compressing medical images by PEG standard and propose two methods for JPEG compression. First, because medical images differ from natural images in optical feature, we propose a method to design adaptively the quantization table using spectrum analysis. Second, because medical images have higher pixel depth than natural images do, we propose a method to design Huffman table which considers the probability distribution feature of symbols. Simulation results show the improved performance compared to the quantization table and the adjusted Huffman table of JPEG standard.

Additional Preamble Definitions for Systems Based on IEEE 802.16 Standard (IEEE 802.16 표준 기반 시스템을 위한 추가적인 프리앰블 정의)

  • Eom, Jaehyung;Seo, Sungwon;Lee, Sungmin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.3
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    • pp.356-362
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    • 2016
  • IEEE 802.16 standard(WiMAX) is one of 3.5G/4G wireless technologies and there are many systems based on the standard. Each frame of the systems begins with a preamble for synchronization and channel estimation, etc. IEEE 802.16 standard defines a total of 114 preamble sequences. By the way there are some systems(such as mobile multi-hop relay) that require using more than 114 preamble sequences. So we define 114 additional preamble sequences in this paper. And we evaluate PAPR and cross-correlation performance of them to decide to be usable as a preamble.

DEVELOPMENT OF A NON-STANDARD FINITE DIFFERENCE METHOD FOR SOLVING A FRACTIONAL DECAY MODEL

  • SAID AL KATHIRI;EIHAB BASHIER;NUR NADIAH ABD HAMID;NORSHAFIRA RAMLI
    • Journal of applied mathematics & informatics
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    • v.42 no.3
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    • pp.695-708
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    • 2024
  • In this paper we present a non-standard finite difference method for solving a fractional decay model. The proposed NSFDM is constructed by incorporating a non-standard denominator function, resulting in an explicit numerical scheme as easy as the conventional Euler method, but it provides very accurate solutions and has unconditional stability. Two examples from the literature are presented to demonstrate the performance of the proposed numerical scheme, which is compared to three methods from the literature. It is found that the method's estimated errors are extremely minimal, such as within the machine precision.

Color Reproduction Modeling of OLED using Standard RBG Display (표준 디스플레이를 이용한 OLED의 색재현성 모델링)

  • Kim, Eun-Su;Lee, Seung-Ik;Park, Kyung-Nam
    • Journal of Korea Society of Industrial Information Systems
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    • v.17 no.7
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    • pp.81-88
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    • 2012
  • This paper proposed the color reproduction modeling of OLED using standard RGB display. The kinds of non-standard RGB displays are various. And color reproduction of non-standard RGB displays is different by chromaticities of primaries and reference white etc. In this paper, we proposed algorithm that made OLED display's color reproduction to standard CRT monitor using conversion matrix. If using the algorism that is proposed in this paper, we can confirm the reproduced color characteristics to simulation beforehand and improve the performance of existing display. when developing new display, we are expected to be used very usefully.

The Building for Safety Regulation DB of Urban Transit System Infrastructure used by Computer Design Tool (전산지원도구를 이용한 도시철도시설 안전기준 DB구축 연구)

  • Lee, Woo-Dong;Shin, Jeong-Ryul;Ahn, Tai-Ki
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.786-790
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    • 2006
  • Urban rail transit offers target performance and function because various lower part system such as rolling-stock, signal, power and trackis consisted as complex. In order to function properly an urban rail transit which is complicated system to work as safety and reliability, System must secure safety with structure, design, manufacture, install and verification and it is important to establish a safety standard follows it procedures, establish what step all it is important to operate. Safety standard of urban transit infrastructure is minimum standard necessary to secure safety of signal, power and track. Urban rail transit standard business leads to make many requirements. Recently, many types of equipment have applied to manage requirements and standards for system efficiently in part of universal, airline and car accordingly applied equipments use to manage a pursuit(Trace) between standard of system. Especially importance of management is emphasized more become more. Importance of standard management which usesa computing support tool recently in transit filed is embossed and is predicted to be more such forward. Therefore we propose the effective method of management with infrastructure system by constructed data-base system.

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The Effect of C Language Output Method to the Performance of CGI Gateway in the UNIX Systems (유닉스 시스템에서 C 언어 출력 방법이 CGI 게이트웨이 성능에 미치는 영향)

  • Lee Hyung-Bong;Jeong Yeon-Chul;Kweon Ki-Hyeon
    • The KIPS Transactions:PartC
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    • v.12C no.1 s.97
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    • pp.147-156
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    • 2005
  • CGI is a standard interface rule between web server and gateway devised for the gateway's standard output to replace a static web document in UNIX environment. So, it is common to use standard I/O statements provided by the programming language for the CGI gateway. But the standard I/O mechanism is one of buffer strategies that are designed transparently to operating system and optimized for generic cases. This means that it nay be useful to apply another optimization to the standard I/O environment in CGI gateway. In this paper, we introduced standard output method and file output method as the two output optimization areas for CGI gateways written in C language in the UNIX/LINUX systems, and applied the proposed methods of each area to Debian LINUX, IBM AIX, SUN Solaris, Digital UNIX respectively. Then we analyzed the effect of them focused on execution time. The results were different from operating system to operating system. Compared to normal situation, the best case of standard output area showed about $10{\%}$ improvement and the worst case showed $60{\%}$ degradation in file output area where some performance improvements were expected.

Performance Appraisal and Job Rotation of the Nurse In a General Hospital (간호사 인사관리 제도에 관한 연구)

  • Kwon, Young-Hee;Lee, Myung-Ha
    • Journal of Korean Academy of Nursing Administration
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    • v.5 no.3
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    • pp.425-444
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    • 1999
  • The purpose of this study is to survey evaluation of the nurse on the current Performance Appraisal System. the need for future performance of the nurse and the opinions about the job rotation, and suggest the direction of improvement by obtaining basic data to improve personnel management of the nurse in a hosipial, the subject of the investigation. The study was conducted self-reporting questionniare survey of 330 nurses working at C hospital located in Chonbuk Province and the data was collected from May 4. 1999 through May 14. The research used measuring instrument developed by researcher for evalution about the present performance appraisal. the need for the future performanc appraisal system and the opinion of job rotaion. The analysis of the collected data was computerized using SPSS/PC+ program, calculated frequency, percentage, the mean and standard deviation and used Pearson, s Correlation Coefficients, t-test, chi- square test. Major findings are as follows. 1) As for the purpose of the current performanc appraisal, the appraiser recognized it as a security of promotion standard, while the employee saw it as a means for control as guidance and supervison of work. 2) With regard to use the result of the present performance appraisal, appraiser picked ambiguous appraisal standard, employees recognized unilateral evaluation of superior eliminated the participation of them as the highest priority. 3) In relation to the current criteria for promotion of the nurse, both appraisers and employees placed more weight on the length of clinical than performance appraisal score. 4) There is much possibility of the appraiser making an error to evaluate considering the length of performance appraisal. 5) Both appraisers and employees indicated that prospective result of performance appraisal should be used for the ability development & motivation of the individual. 6) Concerning employee's participation for performance appraisal both sides wanted by far more participation. 7) Regarding the most ideal appraisal method, both parties favored most the way added up the evaluation of the head nurse and peer review and followed by the manner the revaluation of the head nurse by considering self-evaluation. 8) As to the individual interview after the appraisal, more than 60% of appraisers responded it's not necessary, while above 88.5% of employees answered it is essential so that it is showed significantly difference between the appraisers and the employees. 9) As far as open of the evaluation result is concerned. 75% of the appraiser were against it but 80% of the employee were for it so that it showed significantly between them. The most principal reason that the employee want is that it motivates the individual's ability development and the fairness of the appraisal increases. 10) Whether the periodical rotation is necessary or not, 80% of appraisers and employees answered it's necessary, however, over 70% of them did not want the rotation. 11) Work-group Cohesiveness level within the nursing unit was attentive different from desire of the rotation, that is, the work group cohesiveness level of nurses wanting rotation was significantly lower than that of the group not desiring it.

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Convergent Awareness and Performance of the Standard Operating Procedure in Emergency Medical Technicians Serving as Paramedics (구급대원으로 활동하는 응급구조사의 표준작전절차에 대한 융복합적인 인지도와 수행도)

  • Hwang, Jeong-Hyeon;Lee, Hyeon-Ji
    • Journal of the Korea Convergence Society
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    • v.8 no.10
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    • pp.105-114
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    • 2017
  • The purpose of this study was to examine the convergent awareness of emergency medical technicians serving as paramedics on the standard operating procedure(SOP) and their performance of it. The subjects in this study were 400 selected emergency medical technicians who were working as paramedics, and SPSS 20.0 was employed to make an analysis. The findings of the study were as follows: As for the convergent awareness of the subjects, they were best aware of the prevention of respiratory infections, and they were least aware of hand hygiene. Concerning performance, they performed best in handling treatment equipment and ensuring staff safety, and they performed least well in terms of hand hygiene. Overall, they were rated higher in awareness than in performance. Second, regarding the influence of general characteristics, there were statistically significant differences in awareness according to age, gender and injury experience, and significant differences were found in performance according to career only. The convergent awareness of the emergency medical workers was positively correlated with their performance. Given the findings of the study, it's required to improve both the Standard Operating Procedure awareness and performance of emergency medical workers who serve as paramedics, and it's expected to make it possible to boost their performance when repeated education is provided with the kind of programs that aim at improving awareness.