• Title/Summary/Keyword: variable parameter

Search Result 1,103, Processing Time 0.03 seconds

Characteristics of Gas Furnace Process by Means of Partition of Input Spaces in Trapezoid-type Function (사다리꼴형 함수의 입력 공간분할에 의한 가스로공정의 특성분석)

  • Lee, Dong-Yoon
    • Journal of Digital Convergence
    • /
    • v.12 no.4
    • /
    • pp.277-283
    • /
    • 2014
  • Fuzzy modeling is generally using the given data and the fuzzy rules are established by the input variables and the space division by selecting the input variable and dividing the input space for each input variables. The premise part of the fuzzy rule is presented by selection of the input variables, the number of space division and membership functions and in this paper the consequent part of the fuzzy rule is identified by polynomial functions in the form of linear inference and modified quadratic. Parameter identification in the premise part devides input space Min-Max method using the minimum and maximum values of input data set and C-Means clustering algorithm forming input data into the hard clusters. The identification of the consequence parameters, namely polynomial coefficients, of each rule are carried out by the standard least square method. In this paper, membership function of the premise part is dividing input space by using trapezoid-type membership function and by using gas furnace process which is widely used in nonlinear process we evaluate the performance.

A Study on Service Quality and Customer Loyalty of Foodservice Industry (급식산업의 서비스품질과 고객애호도 연구)

  • Park, Sang-Gyu;Kim, Gyeong-Suk
    • Journal of the Korean Dietetic Association
    • /
    • v.8 no.4
    • /
    • pp.398-407
    • /
    • 2002
  • This study is for confirming and finding which kinds of parameter is on Service Quality and Customer Loyalty of Foodservice Operation. For this, the purpose of the study is investigating the relationship between A Customer Loyalty and the factors which would affect it, relative influence-relation about meditate roles of influence-factors. A study model and several hypotheses were developed regarding the relationships. Moreover, after making a question sheet, based on the collected and analyzed 250 of them. The study model was analyzed with, SPSS 10.0 and AMOS 4.0 program. At first, when the quality of service is high, it directly affects Customer satisfaction. With the result from the study, it is prove that the service quality is very important. On the other hand, the service quality do not directly affect the Customer Loyalty. The second, when the value of service is high, it affects the customer-satisfaction. But, although the value of service is high, it doesn't directly affect the Customer Loyalty. So, it is clear that the value of Service on Foodservice Operations is the variable precedent of customer-satisfaction. The third, when the customer-satisfaction is high, customer loyalty is high. It is necessary to make the strategy about the management of Foodservice for keeping customer-satisfaction steadily. According to this study, the important variables are the value of service, the service quality and customer-satisfaction. With these results, we have to manage the factors for keeping the Customer Loyalty in Foodservice Operations.

  • PDF

Optimal Thresholds from Mixture Distributions (혼합분포에서 최적분류점)

  • Hong, Chong-Sun;Joo, Jae-Seon;Choi, Jin-Soo
    • The Korean Journal of Applied Statistics
    • /
    • v.23 no.1
    • /
    • pp.13-28
    • /
    • 2010
  • Assuming a mixture distribution for credit evaluation studies, we discuss estimating threshold methods to minimize errors that default borrowers are predicted as non defaults or non defaults are regarded as defaults. A method by using statistical hypotheses tests, the most powerful test and generalized likelihood ratio test, for the probability density functions which are defined with the score random variable and the parameter space consisted of only two elements such as the default and non default states is proposed to estimate a threshold. And anther optimal thresholds to maximize classification accuracy measures of the accuracy and the true rate for ROC and CAP curves are estimated as equations related with these probability density functions. Three kinds of optimal thresholds in terms of the hypotheses testing, the accuracy and the true rate are obtained from normal random samples with various means and variances. The sums of the type I and type II errors corresponding to each optimal threshold are obtained and compared. Finally we discuss about their efficiency and derive conclusions.

The Extended Technology Acceptance Model According to Smart Clothing Types (스마트 의류제품 유형에 따른 확장된 혁신기술수용모델)

  • Chae, Jin-Mie
    • Korean Journal of Human Ecology
    • /
    • v.19 no.2
    • /
    • pp.375-387
    • /
    • 2010
  • The Technology Acceptance Model (TAM) presented by Davis (1989) has been regarded as highly explanatory as well as the clearest model in explaining consumers' adoption of innovative technology or products. Existing studies have expanded the model by adding related external variables to improve the explanation depending on the type of innovative technology. This study expanded TAM by adding two more variables, namely consumers' technology innovation and clothing involvement considering the feature of smart clothing. The objectives of this study are as follows: 1. to suggest the extended TAM in explaining the adoption process of smart clothing, 2. to verify the differences in the path hypotheses according to the type of smart clothing. A total of 815 effective samples were collected from adults over 20 years old, and AMOS 5.0 package was employed for data analysis. As a result, it was proved that the extended TAM was appropriate for explaining the process of adopting smart clothing according to the path hypotheses of smart clothing types. Technology innovation and clothing involvement were confirmed as antecedent variables in affecting TAM. The perceived usefulness appeared to be a more crucial variable than the perceived ease of use and attitude was found to be an important parameter in adopting smart clothing. Considering the path hypotheses of MP3 playing clothes, perceived usefulness had a direct influence on acceptance intention unlike other types of smart clothing. As for photonic clothes, the influence of perceived ease of use on attitude was supported while it was rejected in the case of MP3 playing clothes and sensing sportswear.

Analysis on Driving Performance of Linear Induction Motor for Maglev System by Finite Element Method (유한요소법을 이용한 자기부상용 선형유도기의 운전 특성 분석법)

  • Kim, Ki-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.7
    • /
    • pp.4469-4474
    • /
    • 2014
  • This paper proposes a novel analysis method on the driving performance of LIM (linear induction motor) by FEM (finite element method). First, a linear model was converted with a rotation model to perform the dynamic analysis for a long time. Through the FEM model, the slip parameter for the control algorithm could be induced effectively. The LIM for the traction system was performed at a constant V/f in the region of constant torque, and a constant V and variable f in the region of constant power. Several slip characteristic curves according to the voltage and frequency were calculated by FEM in advance. The driving performance was then induced by interpolating the slip characteristic curves according to the load of the vehicle.

Development of a Shower Carrier based on the Needs in Long-term Care Institutions

  • Cho, Deok-Yeon;Ko, Cheol-Woong;Chun, Keyoung-Jin;No, Kon-Woo
    • Journal of the Ergonomics Society of Korea
    • /
    • v.31 no.2
    • /
    • pp.379-388
    • /
    • 2012
  • Objective: This study developed a new shower carrier prototype to reduce caregivers' muscle burden and to increase use convenience by reflecting the needs of domestic long-term care institutions. Background: In the long-term care institutions, one of the ADL(Activities of Daily Life) factors is bathing/showering. Recently, bath/shower-assisting equipment is actively being introduced in care institutions to reduce the caregivers' care cost, but most of the domestic equipment was designed to imitate foreign products and rarely reflected the needs of care institutions. Method: Based on Korean elderly people's body information, the bed size(length: 1,900mm, width: 650mm) was set-up, and a variable headrest with a newly designed headform was developed to provide the comfort for the elderly and convenience for caregivers. To reduce caregivers' muscle burden on transferring and showering activities, a 3-step column lifting module equipped with dual actuators(lowest/highest levels from the ground: 600/1,100mm, Stroke: 500mm) was developed, and the wheelbase parameter(length: 1,250mm, width: 580mm) was defined securing the turn-over safety of the shower carrier. The drivability tests were performed for the prototype and foreign product, and the male and female subject's muscle activities were measured through the tests. Results: The structural stability of the shower carrier prototype was secured by finite element analysis, and the muscle activities of the subjects through the drivability tests largely decreased in the prototype, compared to the foreign product. Conclusion: In this study, a new shower carrier prototype was developed to possibly reduce caregivers' muscle burden and to increase use convenience based on the needs of long-term care institutions. It was expected that the drivability performance of the prototype could be relatively superior to that of the foreign product. Application: The results obtained from the study can be applied for the optimal development of a shower carrier including other equipment to effectively care for the elderly.

Relationship among Nurses' Communication Style, Nursing Service Satisfaction, Hospital Service Satisfaction Perceived by Patients' Family and Intent to Revisit the Hospital (환자가족이 지각하는 간호사의 의사소통 스타일, 간호서비스 만족, 병원서비스 만족과 병원 재이용 의도 관계연구)

  • Seo, Hyang Lan;Eom, Hea Kyoung;Seo, Yu Kyung;Choi, Mi Jung;Im, Shin Il;Shin, Sun Mi;Lee, Mi Hee;Hwang, Seul Ah
    • Journal of Korean Clinical Nursing Research
    • /
    • v.22 no.3
    • /
    • pp.368-378
    • /
    • 2016
  • Purpose: This research aimed at investigating the relationship among nurses' communication style, nursing service satisfaction, hospital service satisfaction, and intent to revisit the hospital. Methods: A correlational study was conducted including 270 family members of patients who were hospitalized in general wards in a general hospital in J city. Collected data were analyzed using SPSS 21.0 and AMOS 21.0. Results: Affective communication style demonstrated the highest correlation with intent to revisit the hospital, followed by informative communication style, and authoritative communication style. Nursing service satisfaction demonstrated indirect effect through the parameter, hospital service satisfaction to the intent to revisit the hospital. Hospital service satisfaction demonstrated direct effect influencing the intent to revisit the hospital. Conclusion: With respect to nursing service, affective communication style is important to promote intent to revisit the hospital. It is necessary to improve nursing service, since it is an important variable that can improve hospital service satisfaction and hospital revisit intent.

A Study on Factors Influencing Purchase Intention of Smartphones on Chinese University Students (중국 대학생들의 스마트폰 구매의도 영향요인에 관한연구)

  • Yu, Ying;Lee, Kidong
    • Journal of Digital Convergence
    • /
    • v.12 no.1
    • /
    • pp.253-261
    • /
    • 2014
  • The purpose of this study is to explore the factors affecting purchase intention of smartphone in Chinese university students. We have identified five independent variables that affecting purchase intention of smartphone, which include price, compatibility, security, social influence and consumer innovations. We test the degree of influence of these five variables on customer satisfaction eventually and on purchase intention. To prove the hypothesis, we performed questionnaire investigation in Qingdao University. and final date of 187 samples were analyzed by using SPSS18.0 program. The result of hypothesis verification is the followings: As the independent variables of compatibility and consumer innovations are affects satisfaction; the price, security and social influence are not affects satisfaction and the satisfaction as the parameter affects the purchase intention which is the dependent variable in this study in Chinese university students. At the end of this study, the marketing implications for advancing to China market based on the results of empirical analysis were presented.

(A Realization of Low Power SRAM by Supply Voltage Detection Circuit and Write Driver with Variable Drivability) (전원전압 감지기 및 가변 구동력을 가진 쓰기 구동기에 의한 저전력 SRAM 실현)

  • Bae, Hyo-Gwan;Ryu, Beom-Seon;Jo, Tae-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.39 no.2
    • /
    • pp.132-139
    • /
    • 2002
  • This paper describes a supply voltage detector and SRAM write driver circuit which dissipates small power. The supply voltage detector generates high signal when supply voltage is higher than reference voltage, but low signal when supply voltage is lower than reference voltage. The write driver utilizes two same-sized drivers to reduce operating current in the write cycle. In the case of lower supply voltage comparing to Vcc, both drivers are active the same as conventional write driver, while in the case of high Vcc only one of two drivers are active so as to deliver the half of the current. As a result of simulation using 0.6${\mu}{\textrm}{m}$ 3.3v/5v, CMOS model parameter, the proposed SRAM scheme shows a 22.6% power reduction and 12.7% PDP reduction at Vcc=3.3V, compared to the conventional one.

A Magnetic Energy Recovery Switch Based Terminal Voltage Regulator for the Three-Phase Self-Excited Induction Generators in Renewable Energy Systems

  • Wei, Yewen;Kang, Longyun;Huang, Zhizhen;Li, Zhen;Cheng, Miao miao
    • Journal of Power Electronics
    • /
    • v.15 no.5
    • /
    • pp.1305-1317
    • /
    • 2015
  • Distributed generation systems (DGSs) have been getting more and more attention in terms of renewable energy use and new generation technologies in the past decades. The self-excited induction generator (SEIG) occupies an important role in the area of energy conversion due to its low cost, robustness and simple control. Unlike synchronous generators, the SEIG has to absorb capacitive reactive power from the outer device aiming to stabilize the terminal voltage at load changes. This paper presents a novel static VAR compensator (SVC) called a magnetic energy recovery switch (MERS) to serve as a voltage controller in SEIG powered DGSs. In addition, many small scale SEIGs, instead of a single large one, are applied and devoted to promote the generation efficiency. To begin with, an expandable mathematic model based on a d-q equivalent circuit is created for parallel SEIGs. The control method of the MERS is further improved with the objective of broadening its operating range and restraining current harmonics by parameter optimization. A hybrid control strategy is developed by taking both of the stand-alone and grid-connected modes into consideration. Then simulation and experiments are carried out in the case of single and double SEIG(s) generation. Finally, the measurement results verify that the proposed DGS with SVC-MERS achieves a better stability and higher feasibility. The major advantages of the mentioned variable reactive power supplier, when compared to the STATCOM, include the adoption of a small DC capacitor, line frequency switching, simple control and less loss.