• Title/Summary/Keyword: Variable controls

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A CONSTRUCTION OF A SEMI-AUTOMATIC TELESCOPE FOR ECLIPSE TIMING OBSERVATIONS OF ECLIPSING BINARY STARS (식쌍성의 극심시각 관측을 위한 소형 반자동 망원경 관측시스템의 구성)

  • 이충욱;박성수;김천휘;변용익
    • Journal of Astronomy and Space Sciences
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    • v.20 no.2
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    • pp.143-152
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    • 2003
  • We constructed the photometric observation system with a small semi-automatic telescope for the systematic observations of eclipse timings of eclipsing binary stars. The system is consisted of a Paramount GT-1100s mount system, a Celestron 14 optical system, and a SBIG ST-8 camera. We developed the OBSTOOL S/W which controls the telescope and the CCD camera using the COM(Component Object Model) supported by the softwares, The Sky and MaximDL. The system performs photometric observations of a variable, comparison and check stars by moving the telescope to the chosen star separately in a similar way such as the method of photoelectric observation. We wrote pert scripts which enable a data handling pipeline for the obtained data to be classified by each of date, object and filter. And thus the images are easily preprocessed using the IRAF S/W package. Eclipse light curves of some eclipsing binary stars observed with this system are presented.

The Effects of Profit-Sharing Schemes on Productivity through Firm's Contribution to the Employee Welfare Fund (사내근로복지기금제도를 통한 이윤공유참여의 생산성효과)

  • Cin, Beom Cheol
    • Journal of Labour Economics
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    • v.26 no.3
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    • pp.115-147
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    • 2003
  • This paper scrutinizes the robustness of the profit-sharing findings first employing an original panel data on the Employee Welfare Fund over the period from 1992 to 2000. In examining the effects of profit-sharing schemes on labor productivity, it controls for simultaneity among profit-sharing, production factors, and productivity using both the two-stage least squares procedure and the lagged variable method. The empirical results show that an increase in firm's contribution to the Employee Welfare Fund is associated with capital-embodied and disembodied productivity enhancement, which is both statistically and economically highly significant. The empirical results are in contrast with predictions of both agency and transaction cost theories, and they imply that more tax benefits and financial incentives for expansion of the Employee Welfare Fund should be required to get productivity gains.

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Cyber Security Management of Small and Medium-sized Enterprises with Consideration of Business Management Environment (중소기업의 기업경영 환경을 고려한 사이버 보안 관리)

  • Chun, Yong-Tae
    • Korean Security Journal
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    • no.59
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    • pp.9-35
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    • 2019
  • Until now, a lot of research on cyber security have been tried, but there have been few studies on overall relationships, including internal factors and external factors. Therefore, this study examined cyber security management considering not only internal elements of SMEs but also corporate management environment. The first qualitative analysis and the second quantitative analysis were conducted through mixed method research. Qualitative analysis was conducted through a semi-structured interview method, and three themes were found: insufficient cyber security management system, internal noncooperation for cyber security, and problems derived from decision-making system. In the quantitative analysis, multiple regression analysis was conducted on the data obtained through the questionnaire. The perception of cyber threats and internal support among independent variables positively influenced the cyber security management system or the dependent variable. Through this study, internal variables had a causal impact on the cyber security management system rather than external environment variables. This implies that the variables related to the organizational culture such as employees' perception are important. These results are expected to provide practical significance for enhancing the cyber security management system in SMEs.

A Comparative Study of Outsourcing Culinary Part of Foodservice Industry Development. (외식사업발전을 위한 조리분야 아웃소싱 전략에 관한 연구 (평가측정치 개발절차를 중심으로))

  • 김기영
    • Culinary science and hospitality research
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    • v.7 no.3
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    • pp.13-34
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    • 2001
  • The case which it contracts with the dynamic result measurement system when actual outsourcing evaluation measurement is composed and then one result standard between the service supplier and the user is set, which owns jointly the expense which is reduced from that or the benefit which is created from that is increasing In the conclusion, for outsourcing management strategy of domestic foodservice industry in order to succeed, first it is accurate and examined that for what and how outsourcing should be introduced and as a result, what kind of result can be raised from that result\ulcorner Food service industry should be outsourced if you want to make more many investment in better humane resources, food & beverage-goods-security and education to provide eating-out service out of various business in food industry. When considering the actuality of the domestic foodservice industry that time it is appropriate, it sees. The foreign-brand goods which is introduced in the country are being executing in the 1ink of part management strategy. One of the most influential factor of domestic foodservice industry's management pressure is overspent management expenses, Does the namely expenses preparation effect reach which degree\ulcorner what kind of method can most decrease these expenses\ulcorner Doing grows the success and failure of the Korean foodservice industry controls result with the fact that it will operate with a big variable sees. The background which the domestic foodservice industry should introduce inevitably the outsiurcing system is to develop continuously nation foodservice industry in the way of cost curtailment of food-material, a labor cost curtailment with efficient application and synergic effect like specialty manpower utilization. The kindred competitive enterprises gradually concentrate management resource to the point ability from the present point of view which is increasing and a strategy position they secure, to prepare a competitive power, what sees it is important national industry must prepare a new paradigm. It is important to measure the result based on sales accomplishment in operation system dimension, and it is more important to appropriately apply regard of the evaluation measurement

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Derivation of a Linear PID Control Law from a Fuzzy Control Theory (퍼지 제어기로부터 PID 제어기의 구현에 관한 연구)

  • 최병재;김병국
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.2
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    • pp.70-78
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    • 1997
  • Proportional-integral-derivative(P1D) controllers have been still widely used in industrial processes due to their simplicity, effectiveness, robustness for a wide range of operating conditions, and the familiarity of control engineers. And a number of recent papers in fuzzy systems are showing that fuzzy systems are universal approximators. That is, fuzzy controllers are capable of approximating any real continuous function on a compact set of arbitrary accuracy. In this paper, we derive the linear PID control law from the fuzzy control algorithm where all fuzzy sets for representing plant state variables and a control variable use common triangular types. We first lead a linear PD control law from a fuzzy logic control with only two fuzzy sets for error and change-of-error. And then we derive the linear PID control law from a fuzzy controller. We here assumed that the intervals of error, change-of-error, and integral error could be partitioned into arbitrary numbers, respectively. As a result, a linear PID controller is only a sort of various fuzzy logic controls.

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A Design of Predistorter for Controlling the Amplitude of Low-Frequency IM Signals (저주파 혼변조 신호의 크기 조절에 의한 전치 왜곡 선형화기 설계)

  • Jang Mi-Ae;Kim Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.1 s.104
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    • pp.45-51
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    • 2006
  • In this paper, a new predistortion linearizer for controlling the amplitude of low frequency intermodulation distortion signals is proposed. The low frequency intermodulation distortion(IMD) components are generated by harmonic generator. A vector modulator, modulate fundamental signal with low frequency IMD signals, generates predistortion IMD signals and controls amplitude and phase of them with modulation factors. As a result, this predistorter is suppressed IMD signals of power amplifier effectively. The predistortion linearizer has been manufactured to operate in cellular base-station transmitting band($869{\sim}894\;MHz$). The experimental results show that IMD3 of power amplifier are improved more than 20 dB for CW two-tone signals. Also, it's improved the adjacent channel power ratio(ACPR) more than 10 dB for IS-95 CDMA IFA signals.

An Integrative Review Of Oncology Nursing Research In Korea: 1998-2003 (국내 종양간호연구 동향에 관한 연구)

  • Oh, Pok-Ja
    • Asian Oncology Nursing
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    • v.3 no.2
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    • pp.112-121
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    • 2003
  • The purpose of these study was to analyze the contents and trend of researches done on oncology nursing in the past five years in Korea and to suggest its direction for the future research. Methods: 214 nursing studies published from 1998 to 2003 were selected for the analysis. They were examined for the source, design of study, type of subjects, the intervention outcomes of experimental research, the key words and theme of the oncology research. Results: 1. 139(64.9%) of 214 studies were masters thesis and doctoral dissertations. There were 196(91.6%) quantitative researches and 18 qualitative researches. Quantitative research consisted of 28(14.3%) experimental and 168(85.7%) non- experimental studies. Among non-experimental studies, there were 53 correlations, 78 descriptives, 14 comparatives and 23 methodological studies. 2.The main subjects of the study were cancer patients in general(43.7%) and breast cancer patients (18.3%). According to the treatment types, patients receiving chemotherapy were the highest number distribution as 23 of all researches. 3. Social support, fatigue, stress, hope, and quality of life were the most frequently used concepts in correlational studies.4. Education, providing information, oral care, exercise, relaxation and foot massage were the most frequent nursing interventions. Most frequently measured outcomes variable were self-care, pain control, nausea & vomiting, oral discomfort and anxiety. 5. Key words used most frequently were quality of life, educational need, pain controls and fatigue. 6. The themes of qualitative researches were illness experience, family experience and adaptation process. More than 50% of qualitative researches used phenomenologic method. Conclusion: Researches on cancer nursing in Korea have been increased. Descriptive design is being dominant and few experimental studies are being done For the future, it is necessary to conduct international studies to compare, replicate and to establish the effective nursing interventions.

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Evaluation of Common Risk Factors for Breast Carcinoma in Females: a Hospital Based Study in Karachi, Pakistan

  • Sufian, Saira Naz;Masroor, Imrana;Mirza, Waseem;Butt, Sehrish;Afzal, Shaista;Sajjad, Zafar
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6347-6352
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    • 2015
  • Background: Breast malignancies are one of the leading causes of deaths in females worldwide. There are a number of risk factors associated with breast cancer but in Karachi Pakistan there are insufficient data available. Materials and Methods: A case control study was conducted on females in age group between 30-80 years. This study was accomplished by retrospective data collection in Aga Khan University Hospital Karachi, Pakistan. A total of 108 females with primary malignancy of breast were included along with 108 matched controls. Relationship of various factors with disease was studied using logistic regression to calculate odds ratios with 95 % confidence intervals. Results: A total of 14 variables were analyzed and based on and 7 were found to be risk factors: old age, family history of breast cancer, family history of other carcinomas, personal history of breast carcinoma, early age of menarche, older age of mother at first delivery and lower number of children. Five factors, parity, breast feeding, history of oral contraceptive pills intake, past history of oophorectomy and hysterectomy showed protective associations. One variable, use of hormonal replacement therapy, showed a controversial link and one other, marital status, was not significant in this study. Conclusions: It is concluded that most of the well-known risk factors for breast cancer are also associated with the disease in the female population of Karachi, Pakistan. High risk patients should be the focus with the help of this study so that screening can be more effective for early diagnosis before clinically evident breast malignancy.

A CONSTRUCTION METHOD OF MULTIPLE CONTROL SYSTEMS USING PARTIAL KNOWLEDGE UPON SYSTEM DYNAMICS

  • Yoshisara, Ikuo;Indaba, Masaaki;Aoyama, Tomoo;Yasunaga, Moritoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.73-78
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    • 1999
  • This paper presents an effective construction method of adaptive multiple control systems utilizing some knowledge upon the plants. The adaptive multiple control system operates plants un-der widely changing environmental conditions. The adaptive multiple control system is composed of a family of candidate controllers together with a supervisor. The system does not require any identification schemes of environmental conditions. Monitoring outputs of the plant, the supervisor switches from one candidate controller to another, The basic ideas of adaptation are as follows: (1)each candidate controller is prepared for each environmental condition in advance; (2)the supervise. applies a sequence of speculative controls to the plant with candidate controllers just after the start of control or just after the detection of a change in the environmental condition. Each candidate controller can keep the system stable during one-step period of the speculative control and the most appropriate candidate controller for the environmental condition to which the system is exposed can be selected before the last trial of speculative control step comes to an end. We proposed a construction method of adaptive multiple control system without any knowledge of plant dynamics and applied the method to a cart-pole balancing problem and a vehicle anti skid braking system. In real applications, as we can often easily obtain a piece of knowledge upon plant dynamics beforehand, we intend to extend the method such that multiple control systems can be efficiently designed using the knowledge. We apply the new idea to the cart-pole balancing problem with variable length of the pole. The simulation experiments lead us to the conclusion that the new attempt can reduce the manpower to design the candidate controllers for adaptive multiple control systems.

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Structural vulnerability analysis and improvement of a biometrics-based remote user authentication scheme of Li and Hwang's (Li & Hwang's 생체기반 인증스킴에 대한 취약성 분석 및 개선)

  • Shin, Kwang-Cheul
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.7
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    • pp.107-115
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    • 2012
  • Recently, Li and Hwang scheme proposed a biometrics-based remote user authentication scheme using smart card. It is asserted that this scheme has very excellent benefits by the operation cost efficiency based on the smart card, one-way function and biometrics using random numbers. But this scheme cannot provide the properly authentication, especially, it is analyzed as the vulnerable security scheme for Denial-of-Service(DoS) attacks by impersonate attacks. The attacker controls the insecure channel, they can easily fabricate messages to pass the user's or server's authentication, and the malicious attacker can impersonate the user to cheat the server and can impersonate the server to cheat the user without knowing any secret information. This paper proposes the strong improved scheme which can respond to multiple attacks by supplementing the function of integrity check from the server which applied variable authenticator and OSPA without exposing the user's password information. It is supplemented pregnable of disguise attack and mutual authentication of Li and Hwang scheme.