• Title/Summary/Keyword: performance of work

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A Numerical and Experimental Study for Fry-drying of Various Sludge (슬러지 유중 건조에 대한 전산 해석 및 실험적 연구)

  • Shin, Mi-Soo;Kim, Hey-Suk;Kim, Byeong-Gap;Hwang, Min-Jeong;Jang, Dong-Soon;Ohm, Tae-In
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.4
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    • pp.341-348
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    • 2010
  • The basic principle of fry drying process of sludge lies in the rapid pressure change of sludge material caused by the change of temperature between oil and moisture due to the difference of specific heat. Therefore, the rapid increase of pressure in drying sludge induces the efficient moisture escape through sludge pores toward heating oil media. The object of this study is to carry out a systematic investigation of the influence of various parameters associated with the sludge fry drying processes on the drying efficiency. To this end, a series of parametric experimental investigation has been made together with the numerical calculation in order to obtain typical drying curves as function of important parameters such as drying temperature, sludge diameter, oil type and sludge type. In the aspect of frying temperature, especially it is found that the operation higher than $140^{\circ}C$ was favorable in drying efficiency regardless of type of waste oil employed in this study. The same result was also noted consistently in the investigation of numerical calculation, that is, in that the sludge particle drying was efficiently made over $140^{\circ}C$ irrespective of the change of particle diameter. As expected, in general, the decrease of diameter in sludge was found efficient both experiment and numerical calculation in drying due to the increased surface area per unit volume. In the investigation of oil type and property, the effect of the viscosity of waste oil was found to be more influential in drying performance. In particular, when the oil with high viscosity, a visible time delay was noticed in moisture evaporation especially in the early stage of drying. However, the effect of high viscosity decreased significantly over the temperature of $140^{\circ}C$. There was no visible difference observed in the study of sludge type but the sewage sludge with a slightly better efficiency. The numerical study is considered to be a quite useful tool to assist in experiment with more detailed empirical modeling as further work.

Optimal Operation of Gas Engine for Biogas Plant in Sewage Treatment Plant (하수처리장 바이오가스 플랜트의 가스엔진 최적 운영 방안)

  • Kim, Gill Jung;Kim, Lae Hyun
    • Journal of Energy Engineering
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    • v.28 no.2
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    • pp.18-35
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    • 2019
  • The Korea District Heating Corporation operates a gas engine generator with a capacity of $4500m^3 /day$ of biogas generated from the sewage treatment plant of the Nanji Water Recycling Center and 1,500 kW. However, the actual operation experience of the biogas power plant is insufficient, and due to lack of accumulated technology and know-how, frequent breakdown and stoppage of the gas engine causes a lot of economic loss. Therefore, it is necessary to prepare technical fundamental measures for stable operation of the power plant In this study, a series of process problems of the gas engine plant using the biogas generated in the sewage treatment plant of the Nanji Water Recovery Center were identified and the optimization of the actual operation was made by minimizing the problems in each step. In order to purify the gas, which is the main cause of the failure stop, the conditions for establishing the quality standard of the adsorption capacity of the activated carbon were established through the analysis of the components and the adsorption test for the active carbon being used at present. In addition, the system was applied to actual operation by applying standards for replacement cycle of activated carbon to minimize impurities, strengthening measurement period of hydrogen sulfide, localization of activated carbon, and strengthening and improving the operation standards of the plant. As a result, the operating performance of gas engine # 1 was increased by 530% and the operation of the second engine was increased by 250%. In addition, improvement of vent line equipment has reduced work process and increased normal operation time and operation rate. In terms of economic efficiency, it also showed a sales increase of KRW 77,000 / year. By applying the strengthening and improvement measures of operating standards, it is possible to reduce the stoppage of the biogas plant, increase the utilization rate, It is judged to be an operational plan.

A Study on Relationship between Physical Elements and Tennis/Golf Elbow

  • Choi, Jungmin;Park, Jungwoo;Kim, Hyunseung
    • Journal of the Ergonomics Society of Korea
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    • v.36 no.3
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    • pp.183-196
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    • 2017
  • Objective: The purpose of this research was to assess the agreement between job physical risk factor analysis by ergonomists using ergonomic methods and physical examinations made by occupational physicians on the presence of musculoskeletal disorders of the upper extremities. Background: Ergonomics is the systematic application of principles concerned with the design of devices and working conditions for enhancing human capabilities and optimizing working and living conditions. Proper ergonomic design is necessary to prevent injuries and physical and emotional stress. The major types of ergonomic injuries and incidents are cumulative trauma disorders (CTDs), acute strains, sprains, and system failures. Minimization of use of excessive force and awkward postures can help to prevent such injuries Method: Initial data were collected as part of a larger study by the University of Utah Ergonomics and Safety program field data collection teams and medical data collection teams from the Rocky Mountain Center for Occupational and Environmental Health (RMCOEH). Subjects included 173 male and female workers, 83 at Beehive Clothing (a clothing plant), 74 at Autoliv (a plant making air bags for vehicles), and 16 at Deseret Meat (a meat-processing plant). Posture and effort levels were analyzed using a software program developed at the University of Utah (Utah Ergonomic Analysis Tool). The Ergonomic Epicondylitis Model (EEM) was developed to assess the risk of epicondylitis from observable job physical factors. The model considers five job risk factors: (1) intensity of exertion, (2) forearm rotation, (3) wrist posture, (4) elbow compression, and (5) speed of work. Qualitative ratings of these physical factors were determined during video analysis. Personal variables were also investigated to study their relationship with epicondylitis. Logistic regression models were used to determine the association between risk factors and symptoms of epicondyle pain. Results: Results of this study indicate that gender, smoking status, and BMI do have an effect on the risk of epicondylitis but there is not a statistically significant relationship between EEM and epicondylitis. Conclusion: This research studied the relationship between an Ergonomic Epicondylitis Model (EEM) and the occurrence of epicondylitis. The model was not predictive for epicondylitis. However, it is clear that epicondylitis was associated with some individual risk factors such as smoking status, gender, and BMI. Based on the results, future research may discover risk factors that seem to increase the risk of epicondylitis. Application: Although this research used a combination of questionnaire, ergonomic job analysis, and medical job analysis to specifically verify risk factors related to epicondylitis, there are limitations. This research did not have a very large sample size because only 173 subjects were available for this study. Also, it was conducted in only 3 facilities, a plant making air bags for vehicles, a meat-processing plant, and a clothing plant in Utah. If working conditions in other kinds of facilities are considered, results may improve. Therefore, future research should perform analysis with additional subjects in different kinds of facilities. Repetition and duration of a task were not considered as risk factors in this research. These two factors could be associated with epicondylitis so it could be important to include these factors in future research. Psychosocial data and workplace conditions (e.g., low temperature) were also noted during data collection, and could be used to further study the prevalence of epicondylitis. Univariate analysis methods could be used for each variable of EEM. This research was performed using multivariate analysis. Therefore, it was difficult to recognize the different effect of each variable. Basically, the difference between univariate and multivariate analysis is that univariate analysis deals with one predictor variable at a time, whereas multivariate analysis deals with multiple predictor variables combined in a predetermined manner. The univariate analysis could show how each variable is associated with epicondyle pain. This may allow more appropriate weighting factors to be determined and therefore improve the performance of the EEM.

The Fashion Professionals Required by the Ladies Apparel Manufacturers in Daegu (대구지역 숙녀복업계 기업주가 요구하는 패션전문인)

  • 김효은
    • Journal of the Korea Fashion and Costume Design Association
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    • v.4 no.1
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    • pp.111-130
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    • 2002
  • This study performed a structural questionnaire survey and non-structural interview of the ladies apparel manufacturers in Daegu on the qualification for the employees, skills required for job performance, job training, automatic manufacturing systems, and the use of computer. The results are as follows. 1. Almost all of the apparel manufacturing systems were Pair System, except one Line System in one company. In terms of outsourcing, most of the manufacturers answered “yes,” and in 1998 the outsourcing process was sewing, but in the year 2002, outsourcing has been increased :12 manufacturers(57.1%) outsourcing most of the processes except patterning, 3(14.3%) outsourcing the finish of sewing. 2. The workforce of 1998 and that of 2002 shows a significant difference(P<. 01) between office work and management. The number of office workers has decreased from 15 down to 5.3 people. On the other hand, that of the management has slightly increased from 5.3 to 9.2 people. The number of the manual workers has decreased from 32.2 to 28.7 people. And the number of tailoring and patterning workers has slightly decreased, but the number has increased in sewing from 3.7 to 7.0 people. 3. The wage of an employee shows a significant difference between a sewing assistant(P<. 01) and a production manager(P<. 05), and the wage of a sewing assistant, in particular, has slightly raised from ₩905,000 to ₩1,054,000. 4. The qualifications required of employees are “cooperative human relations”(30.8%), “diligence,” and “ability for job analysis”(26.9%), and “positive thinking” (15.4%) in 1998, and “ability for job analysis”(38.5%), “cooperative human relations”(34.6%), and “positive thinking” (15.4%) in 2002. The areas for job openings are significantly different(P<. 01) depending on the year. Job openings in the design section has increased from 1(3.8%) to 16 manufacturers (61.5%), and decreased in tailoring section from 22(84.6%) to 2 manufacturers(7.7%). Job openings in the sewing section have increased form 2(7.7%) to 6 manufacturers (23.1%). In terms of sex of the employees, there is a significant difference(P<. 001). 19 companies(73.1%) wanted “male” in 1998, but 8 companies(30.8%) answered that they want “female” and 17 companies(65.4%) answered that “it does not matter.” About the educational background, there was a significant difference between the years. The number of the companies that want junior college graduates with an associate degree has increased(15 companies(57.7%). There was a significant difference(P<. 05) in major of the employee. The number of the companies that want fashion majors has increased from 5(19.2%) to 20(76.9%). 5. In terms of job skills required, there was no significant difference. In 1998, “production skills” (46.2%) and “ability for job analysis” (26.9%) were required, and in 2002, “ability for job analysis” (42.3%) and “emotional skills” (26.9%). 6. In regard to training for job skills, “fashion professional training” has slightly decreased from 65.4% in 1998 to 46.2% in 2002, however, “training for job analysis” has slightly increased from 30.8% in 1998 to 46.2% in 2002, which indicates the fact that “fashion professional training” and “ability for job analysis” have been emphasized. 7. The number of the manufacturers purchased apparel CAD has increased from 1(3.8%) to 3(11.5%), and the number of the manufacturers that have no plan for purchase has increased from 16(61.5%) in 1998 to 15(57.7%), still taking up a big proportion. 8. About the use of computers in manufacturing, there is a significant difference(P<. 05). The number of the manufacturers using computer has increased from 5(19.2%) to 15(57.7%) and that of the manufacturers which do not use computers has decreased from 17(57.7%) to 8(30.8%). 9. In the interviews with the owners of the manufacturers, they pointed that schools should give more weight on practical training courses, the invitation of experts in the specific field, complex production systems, training courses for sewing, field trip courses, and furthering specialty education, personality and vocational education.

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The Empirical Study on the Effects of the Team Empowerment caused by the Team-Based Organizational Structure in KBS (팀제가 팀 임파워먼트에 미치는 영향에 관한 연구;KBS 팀제를 중심으로)

  • Ahn, Dong-Su;Kim, Hong
    • 한국벤처창업학회:학술대회논문집
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    • 2006.04a
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    • pp.167-201
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    • 2006
  • Korean corporations are transforming their vertical operational structure to a team-based structure to compete in the rapidly changing environment and for improved performance. However, a high percentage of the respondents in KBS said that despite the appearance of the present team structure, the organization operates much like a vertically-structured organization. This result can be attributed to the lack of study and implementation toward the goal of empowerment, the key variable for the success of the team-based structure. This study aims to provide policy suggestions on how to implement the process of empowerment, by investigating the conditions that hinder the process and the attitude of the KBS employees. For the cross-sectional study, this thesis examined the domestic and international references, conducted a survey of KBS employees, personal interviews and made direct observations. Approximately 1,200 copies of the Questionnaire were distributed and 474 were completed and returned. The analysis used SPSS 12.0 software to process the data collected from 460 respondents. For the longitudinal-study, six categories that were common to this study and "The Report of the Findings of KBS Employees' View of the Team Structure" were selected. The comparative study analyzed the changes in a ten-month period. The survey findings showed a decrease of 24.2%p in the number of responses expressing negative views of the team structure and a decrease of 1.29%p in the number of positive responses. The findings indicated a positive transformation illustrating employees' improved understanding and approval of the team structure. However, KBS must address the issue on an ongoing basis. It has been proven that the employee empowerment increases the productivity of the individual and the group. In order to boost the level of empowerment, the management must exercise new, innovative leadership and build trust between the managers and the employees first. Additional workload as a result of shirking at work places was prevalent throughout all divisions and ranks, according to the survey data. This outcome leads to the conclusion that the workload is not evenly distributed or shared. And the data also showed the employees do not trust the assessment and rewards system. More attention and consideration must be paid to the team size and job allocation in order to address this matter; the present assessment and rewards system need to be complemented. The type of leadership varies depending on the characteristics of the organization's structure and employees' disposition. KBS must develop and reform its own management, leadership style to suit the characteristics of individual teams. Finally, for a soft-landing of KBS team structure, in-house training and education are necessary.

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Personality Factors of Sales Force and Individuals - Impact on the Degree of Environmental Compatibility Job Satisfaction, Turnover : Based on the Insurance Agents (영업인력의 성격요인과 개인-환경적합성이 직무만족도, 이직의도에 미치는 영향: 보험설계사를 중심으로)

  • Kim, Dong Heui;Ha, Kyu-Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.2
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    • pp.121-134
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    • 2016
  • The current insurance market is facing a real problem that the high cost of insurance spent in maintaining a non- face-to-face sales channels face of the channel facing growing contribution to the reduction of side. As a result, the productivity issue facing designers of representative organizations in the organization channel will be referred to an urgent problem. As a result of improved organizational productivity architect that is the goal of this study to demonstrate what a performance improvement factor of insurance agents. Personality factors and individual insurance agents individual-environmental suitability and job satisfaction, consider the impact on turnover intention year of the results architects extroversion, sincerity, openness, it won a chronic, emotional gender, personality representing the honesty factor is organizational commitment and job satisfaction It has had a significant impact on. In other words, this is a lively and extroverted nature of the actuary, the more harmonious interpersonal relationships and higher emotional empathy with others can raise the extent that has a strong sense of belonging and attachment to their company's commitment. Whereas personality factors were not significant influence turnover intention has. This can be made to represent the need for screening of agents introduced from the introduction stage. Depending on the personality factors of organizational commitment, personal planners also occurs because of the differences and job satisfaction. Whereas turnover of agents is the result of empirical factors that are affected by other agents than to individual character generated by the character of the individual agents. Compliance boss, job suitability, individuals representing a fellow fitness, tissue compatibility environmental compliance is having a significant impact on both the degree of organizational commitment, job satisfaction and turnover intention. In other words, the boss or colleague, values and personality, working method, as fits well the concerns and pursuing goals are similar, and their job aptitude higher the suitability of the organization is about to have a sense of belonging and attachment to the company commitment can do. This is the result of a demonstration that the work environment of the actuary agents productivity gains and loyalty depends on the insurance company, which currently belongs.

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The Medical Doctors' Opinion of Public Health Center on the Development and Supply of Medical Doctor for Public Health Sector (공공보건분야 의사 인력 양성과 개발에 대한 보건소 근무 의사들의 인식)

  • Lee, Kyeong-Soo;Lee, Jung-Jeung;Kim, Jin-Sam;Hwang, Tae-Yoon;Son, Hyo-Kyung;Kim, Chun-Bae
    • Journal of agricultural medicine and community health
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    • v.34 no.3
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    • pp.303-315
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    • 2009
  • Objectives: This study, as for activating measures for capable medical physicians to penetrate into the public health sector, is to provide a basic informations which are used for the enlargement of human resources of physicians in the public health sector, by investigating the perception of physicians, who are now working in the public health center, on the training and development of physicians in the public health sector. Methods: The subjects of this study were 126 individuals. The data was analyzed by frequency analysis using SPSS ver. 17.0K. Results: According to the investigation of 'how to support physicians in public health sector', the necessity of almost questions is considered to be important. Especially, regarding to investigation on 'obstacles of physicians' entrance to public health sector', 'relatively low salary' and 'lack of promotion chances' were thought to be considerable. The most significant education programs to work for public health sector is to improve the ability of health administration planning and service performance. Conclusions: The important methods to reinforce and easily obtain the human resources of physicians in public health sector are not only to improve the penetration of physicians to public health sector, but also to enhance the ability of present physicians, even though sufficient recruitment of physicians is essential.

A Comparison between Multiple Satellite AOD Products Using AERONET Sun Photometer Observations in South Korea: Case Study of MODIS,VIIRS, Himawari-8, and Sentinel-3 (우리나라에서 AERONET 태양광도계 자료를 이용한 다종위성 AOD 산출물 비교평가: MODIS, VIIRS, Himawari-8, Sentinel-3의 사례연구)

  • Kim, Seoyeon;Jeong, Yemin;Youn, Youjeong;Cho, Subin;Kang, Jonggu;Kim, Geunah;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.37 no.3
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    • pp.543-557
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    • 2021
  • Because aerosols have different spectral characteristics according to the size and composition of the particle and to the satellite sensors, a comparative analysis of aerosol products from various satellite sensors is required. In South Korea, however, a comprehensive study for the comparison of various official satellite AOD (Aerosol Optical Depth) products for a long period is not easily found. In this paper, we aimed to assess the performance of the AOD products from MODIS (Moderate Resolution Imaging Spectroradiometer), VIIRS (Visible Infrared Imaging Radiometer Suite), Himawari-8, and Sentinel-3 by referring to the AERONET (Aerosol Robotic Network) sun photometer observations for the period between January 2015 and December 2019. Seasonal and geographical characteristics of the accuracy of satellite AOD were also analyzed. The MODIS products, which were accumulated for a long time and optimized by the new MAIAC (Multiangle Implementation of Atmospheric Correction) algorithm, showed the best accuracy (CC=0.836) and were followed by the products from VIIRS and Himawari-8. On the other hand, Sentinel-3 AOD did not appear to have a good quality because it was recently launched and not sufficiently optimized yet, according to ESA (European Space Agency). The AOD of MODIS, VIIRS, and Himawari-8 did not show a significant difference in accuracy according to season and to urban vs. non-urban regions, but the mixed pixel problem was partly found in a few coastal regions. Because AOD is an essential component for atmospheric correction, the result of this study can be a reference to the future work for the atmospheric correction for the Korean CAS (Compact Advanced Satellite) series.

A Case Study on the classroom life and the identity of the Elementary Mathematics Gifted Education (초등수학 영재교육원의 교실 생활과 정체성에 대한 사례연구)

  • Lee, Hak-Ro;Ryu, Sung-Rim
    • Communications of Mathematical Education
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    • v.25 no.1
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    • pp.99-118
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    • 2011
  • For this case study of gifted education, two classrooms in two locations, show life in general of the gifted educational system. And for this case study the identity of teachers and the gifted, help to activate the mathematically gifted education for these research questions, which are as followed: Firstly, how is the gifted education classroom life? Secondly, what kind of identity do the teachers and gifted students bring to mathematics, mathematics teaching and mathematics learning? Being selected in the gifted children's education center solves the research problem of characteristic and approach. Backed by the condition and the permission possibility, 2 selected classes and 2 people, which are coming and going. Gifted education classroom life, the identity of teachers and gifted students in mathematics and mathematics teaching and mathematic learning. It will be for 3 months, with various recordings and vocal instruction between teacher and students. Collected observations and interviews will be analyzed over the course of instruction. The results analyzed include, social participation, structure, and the formation of the gifted education classroom life. The organization of classes were analyzed by the classes conscious levels to collect and retain data. The classes verification levels depended on the program's first class incentive, teaching and learning levels and understanding of gifted math. A performance assessment will be applied after the final lesson and a consultation with parents and students after the final class. The six kinds of social participation structure come out of the type of the most important roles in gifted education accounts, for these types of group discussions and interactions, students must have an interaction or individual activity that students can use, such as a work product through the real materials, which release teachers and other students for that type of questions to evaluate. In order for the development of meaningful mathematical concepts to formulate, mathematical principles require problem solving among all students, which will appear in the resolution or it will be impossible to map the meaning of the instruction from which it was formed. These results show the analysis of the mathematics, mathematics teaching, mathematics learning and about the identity of the teachers and gifted. Gifted education teachers are defined by gifted math, which is more difficult and requires more differentiated learning, suitable for gifted students. Gifted was defined when higher level math was created and challenged students to deeper thinking. Gifted students think that gifted math is creative learning and they are forward or passive to one-way according to the education atmosphere.

A Study on the Management Activities and the Characteristic of Food Restaurant Entrepreneur (외식업 창업자의 특성과 경영관리활동에 관한 연구)

  • Kim, Tae Hoon;Hong, Hyo Seok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.2
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    • pp.1-13
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    • 2014
  • This study is preliminary founding start-ups of restaurant entrepreneurs to study the characteristics of management in order to provide useful information was studied. Survey period is from 2013 March 15 to August 31. About the nature of the preparation and establishment founder findings restaurant entrepreneurs of Western Gyeongnam area were most often in the form of an independent establishment has been compiled, work experience and other industries operating experience was more than restaurant entrepreneurs of operating experience. Hypothesis Testing in accordance with results of this study are as follows. First, the 50 founders than 30 founders quickly when the customer complaint or that service, order food and non-food note is issued after obtaining the order or that provide food, no customer is often inconvenient check the sharing services, such as personnel activities were devoting a lot of effort. Second, the re-startups restaurant entrepreneurs than new startups restaurant entrepreneurs was founded after the founder of career-related customer complaints about food more active coping was, and re-startups restaurant entrepreneurs by the founder other than business founded by the founder of the food-related customer complaints more aggressively for coping, respectively. Third, restaurant entrepreneurs of the store operations management has integrity, words and actions match, such as the degree of belief in the promise of reliability and the possibility of failure, which means the degree of recognition and response efforts are having an impact deal. Fourth, restaurant of food service management services and after-sales service has impact on the founder of the self-efficacy and self-efficacy of pre-service features and reliability founder affecting. Fifth, the revenue of the restaurant for dealing with customer complaints management includes efforts are having an impact. Sixth, restaurant founder of reliability and customer care has influenced the self-efficacy. Seventh, management of operational management activities have a positive impact on business performance are.

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