• 구강회복응용과학지
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• 제18권2호
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• pp.81-91
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• 2002

Dental implant systems have shown many post-surgical problems and One of the most frequent problem is screw loosening. To reduce screw loosening, a number of methods have been tried and recently fundamental modification of fixture-abutment connection structure was developed and used the most frequently. Former implant system structure, such as Br${\aa}$nemark, had external hex with the height of 0.7 mm and later, fixture with external hex of 1.0 mm height and internal hex structure were developed. In addition, the method of morse taper application was introduced to reduce screw loosening. In this study, the level of screw loosening of each implant systems was compared based on the vibration loosening measurement of abutment screw of each implant systems. Analysis of measured value was performed using 3 kinds of methods, (i) Percentage of average of initial 3 times loosening-torque value(initial loosening value) to tightening-torque of 30 Ncm, (ii) Percentage of loosening-torque value after 200 N strength loaded(experimental value) to initial loosening value and (iii) Percentage of experimental value to 30 Ncm of tightening-torque. Each result of analyses shows the value of initial loosening, loosening by repetitive load and final loosening level. The results of this study were as follows. (1) Percentage of initial loosening value to tightening-torque was increased in order of 0.7 mm external hex, 1.0 mm external hex, internal hex and internal taper and all values between each groups showed statistical significance (p<0.05). (2) Percentage of experimental value to initial loosening value was increased in order of internal hex, 0.7 mm external hex, 1.0 mm external hex and internal taper. Value of internal taper showed significant difference with that of 0.7 mm external hex and internal hex (p<0.05). (3) Percentage of experimental value to tightening torque was increased in order of 0.7 mm external hex, 1.0 mm external hex, internal hex and internal taper. Values of all groups showed statistical significance (p<0.05) except between the groups of 1.0 mm external hex and internal hex. Based on those results, there was no significant difference of loosening-torque by repetitive loading except internal taper. It is supposed that implant system with high resistant capability against initial loosening could be recommended for clinical use. In addition, in case of single implant restoration, 1.0 mm external hex or internal hex could be recommended rather than 0.7 mm external hex, and the use of internal taper would be the most useful way to reduce screw loosening.

• 동아시아경상학회지
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• 제8권4호
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• pp.1-18
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• 2020

Purpose - The current study attempts to reveal the causal relationship and identify the interrelationships among individual value, product selection attribute, and re-purchase intention of consumers when purchasing kimchi. Research design, data, and methodology - The surveys were distributed and retrieved to kimchi consumers in Seoul and Gyeonggi Province who were over 20 years old and who had purchased kimchi before. The current study utilized the self-reporting survey as the research method. Result - First, as a result of hypothesis 1 test, both internal value and external value had a significant effect. Second, as a result of hypothesis 2 test, while internal value had a significant effect, external value did not have a significant effect. Third, as a result of hypothesis 3 test, while internal value had a significant effect, external value did not have a significant effect. Fourth, as a result of hypothesis 4 test, all quality, brand, and price had a significant effect. Fifth, as a result of hypothesis 5 test, while internal value had a significant effect, external value did not have a significant effect. Conclusion - The current study aims to establish marketing and service strategies to maximize profits and secure competitive advantage in the kimchi industry through changes in the management strategy of the Korean kimchi industry.

• 한국조리학회지
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• 제22권8호
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• pp.78-88
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• 2016

This study conducted to find influences of selection attributes on consumer satisfaction as perceived by low-cost restaurant visiter by considering personal value. Developed survey was distributed and 428 sample who visited the low-cost franchise restaurant were employed the statistical analyze. The internal value and the external value included individual value in order to estimate the influence of the choice factor of the low-cost franchise restaurant on the quality of the product, and the choice factors were consisted of 3 variables that are quality, accessibility and service. Regression analysis was conducted to verify the relationships among the variables. As a result, the internal value (${\beta}=.236$, p<.0.01), and external value (${\beta}=.352$, p<.001) have the significant positive relationships with respect to quality. Second, the external value (${\beta}=.305$, p<.001) has the positive relationship with regard to accessibility, but the internal value has no significant relationships with level of accessibility. Third, the internal value (${\beta}=.828$, p<.001) has the significant positive relationship with regard to service, but there was no significant influences between external value and service in this study. Fourth, the internal value (${\beta}=.472$, p<.001), the external value (${\beta}=.479$, p<.001) were critical antecedents of the quality. Last, while quality (${\beta}=.858$, p<.001) has significant positive relationship with satisfaction, but it didn't show any relationships with accessibility and service.

• 한국콘텐츠학회논문지
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• 제22권8호
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• pp.307-317
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• 2022

본 연구는 사회적기업을 대상으로 사회적기업의 사회적가치 실현노력이 사회적기업의 성과에 미치는 영향 및 사회적 지원환경의 매개효과를 분석하였다. 분석을 위하여 사회적기업진흥원에서 사회적기업을 대상으로 실시한 '사회적경제 지역생태계 구축을 위한 지역자원 조사' 공개데이터 자료를 이용하여 통계 분석을 실시하였다. 분석결과 사회적기업의 사회적가치실현노력은 사회적기업의 사회적 성과와 경제적성과에 직접적인 영향을 미치는 것으로 나타났다. 특히 기업의 외부지원환경은 사회적가치실현 노력과 사회적 성과 간 각각 매개효과가 있는 것으로 나타났다. 그러나 Process for SPSS 4.0을 통한 매개효과의 통계적 유의성 검증결과, 외부지원환경은 사회적 가치실현노력과 사회적 성과 간 매개효과가 유의미했으나 경제적 성과에서는 매개효과가 비유의적이었다. 이로써 사회적 가치실현노력이라는 사회적자본이 사회적 성과에 미칠 수 있는 외부지원환경의 역할을 기대할 수 있을 것으로 보인다.

• 대한치과보철학회지
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• 제46권6호
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• pp.561-568
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• 2008

STATEMENT OF PROBLEM: Currently, many implant systems are developed and divided into two types according to their joint connection: external or internal connection. Regardless of the connection type, screw loosening is the biggest problem in implant-supported restoration. PURPOSE: The purpose of this study is to assess the difference in stability of abutment screws between the external and internal hexagonal connection types under cyclic loading. MATERIAL AND METHODS: Each of the 15 samples of external implants and internal abutments were tightened to 30 N/cm with a digital torque gauge, and cemented with a hemispherical metal cap. Each unit was then mounted in a $30^{\circ}$ inclined jig. Then each group was divided into 2 sub-groups based on different periods of cyclic loading with the loading machine (30 N/ cm - 300 N/cm,14 Hz: first group $1{\times}10^6$, $5{\times}10^6$ cyclic loading; second group $3{\times}10^6$, $3{\times}10^6$ for a total cyclic loading of $6{\times}10^6$) The removal torque value of the screw before and after cyclic loading was checked. SPSS statistical software for Windows was used for statistical analysis. Group means were calculated and compared by ANOVA, independent t-test, and paired t-test with ${\alpha}$=0.05. RESULTS: In the external hexagonal connection, the difference between the removal torque value of the abutment screw before loading, the value after $1{\tims}10^6$ cyclic loading, and the value after $1{\times}10^6$, and additional $5{\times}10^6$ cyclic loading was not significant. The difference between the removal torque value after $3{\times}10^6$ cyclic loading and after $3{\times}10^6$, and additional $3{\times}10^6$ cyclic loading was not significant. In the internal hexagonal connection, the difference between the removal torque value before loading and the value after $1{\times}10^6$ cyclic loading was not significant, but the value after $1{\times}10^6$, and additional $5{\times}10^6$ cyclic loading was reduced and the difference was significant (P < .05). In addition, in the internal hexagonal connection, the difference between the removal torque value after $3{\times}10^6$ cyclic loading and the value after $3{\times}10^6$, and additional $3{\times}10^6$ cyclic loading was not significant. CONCLUSION: The external hexagonal connection was more stable than the internal hexagonal connection after $1{\times}10^6$, and additional $5{\times}10^6$ cyclic loading (t = 10.834, P < .001). There was no significant difference between the two systems after $3{\times}10^6$, and additional $3{\times}10^6$ cycles.

• 대한치과보철학회지
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• 제43권5호
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• pp.671-683
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• 2005

Statement of problem: The most commonly reported problem associated with dental implant restoration is the loosening of the screws. Purpose: This study compared the efficacy of an implant system incorporating an anti-rotational locking sleeve(Anti-Rotating Inner Post Screw System(ARIPS-system)) with other, traditional implant systems as a means of minimizing vibration loosening. Materials and methods: Three implant systems were examined; the conventional external hex type, the ARIPS-system, and the internal taper type implant system 30 specimens(10 samples per group)were fabricated and each abutment screw was secured to the implant future with 32Ncm of torque force and loosening torque was measured using a Torque Gauge. The procedure was repeated 3 times, recording initial loosening torque each time. The re-tightened abutment screw was subjected to a cyclic load having a maximum forte of 200N and minimum of 20N at 2Hz over a period of 12,600 cycles. after which the loosening torque was measured. Measured values were calaulated for statistical analysis. Analysis of measured value was performed by 3 methods: (i) as a percentage average of the initial 3 loosening-torque values(initial loosening value) to the tightening torque of 32Ncm, (ii) as a percentage of the loosening torque value after a load of 200N(experimental value) to the initial loosening value, and (iii) as a percentage of the experimental value to the 32Ncm of tightening torque. The analyses shows the amount of initial loosening at the screw, loosening by repetitive load and the the final loosening value. Results: The results of this study were as follows (1) Percentage of initial loosening value to tightening-torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). (2) Percentage of experimental value to initial loosening value was increased in order of external hex, ARIPS-system and internal taper. Value of internal taper showed significant difference with those of external hex and ARIPS-system (p<0.05). (3) Percentage of experimental value to tightening torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). Conclusion: The results of the analysis of the final loosening level value, which are closely correlated to clinical use, show that the ARIPS-system can be a useful means of minimizing abutment screw loosening when compared to the external hex type system. Although further clinical studies need to be made, the ARIPS-system should be considered to maximize the long-term success of the implant prosthesis.

• 전기학회논문지
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• 제62권8호
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• pp.1163-1168
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• 2013

The maximum allowable value of loop impedance($Z_s$) to secure the operation of overcurrent protective devices and the safety for indirect contact is a very important in TN-C-S system. The loop impedance is divided into inner loop impedance which consumer can adjust and external loop impedance($Z_e$) which only electric operator can adjust. Thus, an external loop impedance which limits to less than a certain value is a very important factor for human body protection against electric shock in TN-C-S system. The concept of loop impedance($Z_s$) is recently introduced to the domestic, the study about external loop impedance is yet insufficient. However, the study about the reference impedance as specified by the IEC 60725 standard to improve the quality and reliability of the power supply is being made. In this paper, reference value of external loop impedance($Z_e$) to meet domestic environment will be proposed by the nationwide measurement and statistical analysis.

• The Journal of Advanced Prosthodontics
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• 제7권4호
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• pp.288-293
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• 2015

PURPOSE. The aim of this study was to evaluate the effect of cyclic loading and screw retightening on reverse torque value (RTV) in external and internal type implants. MATERIALS AND METHODS. Cement-retained abutments were connected with 30 Ncm torque to external and internal type implants. Experimental groups were classified according to implant connection type and retightening/loading protocol. In groups with no retightening, RTV was evaluated after cyclic loading for 100,000 cycles. In groups with retightening, RTV was measured after 3, 10, 100 cycles as well as every 20,000 cycles until 100,000 cycles of loading. RESULTS. Every group showed decreased RTV after cyclic loading. Before and after cyclic loading, external type implants had significantly higher RTVs than internal type implants. In external type implants, retightening did not affect the decrease in RTV. In contrast, retightening 5 times and retightening after 10 cycles of dynamic loading was effective for maintaining RTV in internal type implants. CONCLUSION. Retightening of screws is more effective in internal type implants than external type implants. Retightening of screws is recommended in the early stage of functional loading.

• 대한가정학회지
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• 제44권11호
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• pp.67-78
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• 2006

Self-concept is a multi-dimensional characteristic including self-image and self-evaluation. Self-image is the descriptive side of self-concept and is composed of the real self-image and the ideal self-image. Self-evaluation is the appraisable side self-concept and is composed of the internal self-concept, external self-concept and total score of self-concept. The purposes of this study were to determine the correlation of self-image and self-evaluation and to identify the effects of self-image and self-evaluation on consumption value. The data were collected from 237 college women residing in Gwangju using a questionnaire to investigate real/ideal self-image, self-evaluation and consumption value. The results were analyzed with factor analysis, Pearson's correlation and multiple regression analysis using statistical program SPSS 10.0. The results of this research were as follows. 1. The real self-image and ideal self-image had a significant correlation with internal self-concept, external self-concept and total score of self-concept. It was ensured that self-image and self-evaluation are one side of the multidimensional self-concept. 2. The real/ideal self-image and internal/external self-evaluation had a significant influence on consumption value. The real self-image and external self-evaluation were the most important variables explaining the consumption value.

• 벤처창업연구
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• 제17권5호
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• pp.17-30
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• 2022

불확실한 환경에서 창업하는 기술창업기업의 경쟁우위에 동적역량이 매우 중요한 영향을 미친다는 점은 여러 연구에서 검증되어왔다. 그리고 이런 동적역량에는 외부기관 네트워크가 중요한 영향을 미친다. 이는 자원과 지식이 부족한 창업기업에게 더욱 중요하다. 동적역량에 직접적으로 유의한 영향을 미치는 네트워크는 가치사슬내부 네트워크 위주로 연구되어 왔다. 하지만 창업기업의 네트워크 활동은 가치사슬내부 네트워크 뿐만 아니라 가치사슬외부 네트워크와도 이루어지고 있다. 따라서 창업기업의 네트워크 활동이 동적역량에 미치는 영향을 연구하기 위해서는 두 가지 네트워크가 모두 포괄된 연구가 필요하지만, 선행연구가 부족하다. 본 연구에서는 기술창업기업을 대상으로 가치사슬외부 네트워크와 가치사슬내부 네트워크를 포괄하는 모델을 구성하고, 동적역량과 경쟁우위에 미치는 영향을 실증하는 연구를 진행하였다. 연구결과, 가치사슬내부와의 네트워크 활동은 선행연구와 마찬가지로 동적역량에 직접적으로 유의한 영향을 주었고, 가치사슬외부와의 네트워크 활동은 동적역량에 직접적으로 유의한 영향을 주지 않았다. 그리고 동적역량은 경쟁우위에 유의한 영향을 주었다. 추가연구를 통해 확인한 바, 가치사슬외부와의 네트워크 활동은 가치사슬내부와의 네트워크 활동에 영향을 주고 이를 통해 동적역량을 강화하며, 이를 통해 경쟁우위에 긍정적인 영향을 주는 매개효과가 유의하였다. 이를 통해 창업기업이 동적역량을 강화하여 경쟁우위를 높이기 위해서는 가치사슬내부 네트워크가 중요하다는 점과 가치사슬내부 네트워크는 강하게, 다양하게 맺는 것은 모두 동적역량을 높여 경쟁우위에 긍정적 영향을 준다는 점을 확인할 수 있었다.