• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.291.1-291.1
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• 2016

Graphene by one of the two-dimensional (2D) materials has been focused on electronic applications due to its ultrahigh carrier mobility, outstanding thermal conductivity and superior optical properties. Although graphene has many remarkable properties, graphene devices have low on/off current ratio due to its zero bandgap. Despite considerable efforts to open its bandgap, it's hard to obtain appropriate improvements. To solve this problem, heterojunction barristor was proposed based on graphene. Mostly, this heterojunction barristor is made by transition metal dichalcogenides (TMDs), such as molybdenum disulfide ($MoS_2$) and tungsten diselenide ($WSe_2$), which have extremely thickness scalability of TMDs. The heterojunction barristor has the advantage of controlling graphene's Fermi level by applying gate bias, resulting in barrier height modulation between graphene interface and semiconductor. However, charged impurities between graphene and $SiO_2$ cause unexpected p-type doping of graphene. The graphene's Fermi level modulation is expected to be reduced due to this p-doping effect. Charged impurities make carrier mobility in graphene reduced and modulation of graphene's Fermi level limited. In this paper, we investigated theoretically and experimentally a relevance between graphene's Fermi level and p-type doping. Theoretically, when Fermi level is placed at the Dirac point, larger graphene's Fermi level modulation was calculated between -20 V and +20 V of $V_{GS}$. On the contrary, graphene's Fermi level modulation was 0.11 eV when Fermi level is far away from the Dirac point in the same range. Then, we produced two types heterojunction barristors which made by p-type doped graphene and graphene treated 2.4% APTES, respectively. On/off current ratio (32-fold) of graphene treated 2.4% APTES was improved in comparison with p-type doped graphene.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.425-435
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• 2015

While managerial coaching has increased popularly as an effective leadership initiative in organization, the relationship between managerial coaching and its effects on performance has not been scholarly well defined. This study examined the role of managerial coaching as a moderator between job characteristics and job performance. Based on the sample of 453 employees in a financial firm, HLM was conducted to test the research model at multiple levels of organizational hierarchies. First, we found that managerial coaching has a direct impact on employee performance. Second, the strength of the relationship between job meaningfulness and job performance is positively related to the level of managerial coaching. Third, managerial coaching positively moderates the association between autonomy and job performance. However, any cross-level moderating effects of managerial coaching on the relationship between feedback and job performance is not observed. These results show that managerial coaching by managers could promote employees' performance through maximizing the impact of job characteristics on employees' motivation.

• Korean Journal of Social Welfare
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• v.44
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• pp.7-35
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• 2001

Little empirical study has been conducted concerning board function effectiveness and organizational performance in nonprofit nongovernmental human service organizations in Korea. Using the evaluations of 107 board members and 17 executive directors in Korean Community Chest and 16 regional community chests, this study attempted to examine the level of board function effectiveness and its relationship with organizational performance in these community chests. This study used board function scale developed by Holland and Jackson (1998) to measure board function effectiveness in the following 6 dimensions: contextual dimension: educational dimension: interpersonal dimension: analytical dimension: political dimension: and strategic dimension. This study showed that using 4 points scale, mean of overall board function effectiveness evaluated by board members is 2.62 and mean of overall board function effectiveness evaluated by executive directors is 2.73. That is, it showed that means of overall board function effectiveness are located in the middle point between negative evaluation and positive evaluation. On the other hand, using parametric correlation analysis method, it was found that in these community chests the association between board function effectiveness and organizational performance measured by fund-raising growth rate in $1999{\sim}2000\;and\;1998{\sim}2000$ is very weak and statistically nonsignificant. This study also revealed that using nonparametric correlation analysis method, the association between consensus level in evaluation by board members and executive directors about board function effectiveness, and organizational performance is still very weak and statistically nonsignificant. Finally, this study discussed the direction of future research in board function effectiveness and its relationship with organizational performance and the areas of board management that requires substantial efforts for promoting effectiveness of nonprofit human service organizations in Korea.

• Journal of Power Electronics
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• v.14 no.6
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• pp.1233-1242
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• 2014

A new inverter topology for single-phase photovoltaic (PV) systems is proposed in this study. The proposed inverter offers a four-level voltage in its output terminals. This feature results in easier filtering in comparison with other conventional two-level or three-level inverters. In addition, the proposed four-level inverter (PFLI) has a transformer-less topology, which decreases the size, weight, and cost of the entire system and increases the overall efficiency of the system. Although the inverter is transformer-less, it produces a negligible leakage ground current (LGC), which makes this inverter suitable for PV grid-connected applications. The performance of the proposed inverter is compared with that of a four-level neutral point clamped inverter (FLNPCI). Theoretical analysis and computer simulations verify that the PFLI topology is superior to FLNPCI in terms of efficiency and suitability for use in PV transformer-less systems.

• Journal of Korean Society for Quality Management
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• v.45 no.1
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• pp.93-116
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• 2017

Purpose: The purpose of this study is to suggest a key quality factor affecting user satisfaction based on quality attribute of weather information system and additionally, a managerial implication for activating weather information service market by analyzing causal relevance between weather information system and business performance. Methods: As its method, a causal relevance of quality factor of weather information system affecting satisfaction and business performance was analyzed by using structural equation model. An enterprise utilized in analysis sample performed a survey by targeting 186 distribution/logistics and general manufacturing company. Results: It was revealed that information, service quality of weather information system exerted a significant influence on user satisfaction and it did not take a significant influence on business performance in terms of quality of information, system and service. A significant relevance between user satisfaction and business performance was strong supported. Finally, it was revealed that utilization level of weather information system had a moderating effect on business performance. Conclusion: Domestic weather information system mainly focused on information utilization based weather information system and additional service level utilizing weather information is very low in practical terms. Therefore, in order to expand domestic weather related service market, systematic market expansion strategy of providing corporate customized service and case enlargement would be required.

• Journal of Korean Academy of Nursing Administration
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• v.18 no.2
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• pp.202-212
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• 2012

Purpose: As Evidence-Based Practice (EBP) has increasingly been proven as a means of cost-effective and higher-quality healthcare, its successful implementing are challenging. This study done to identify EBP beliefs, knowledge and performance among nurses experienced as a preceptor. Method: A descriptive cross-sectional survey was conducted with a convenience sample of 249 preceptor nurses working in 9 general hospitals in Korea. Reliable and valid questionnaires (EBP beliefs scale, Evidence Based Practice Questionnaire, Research-related activities) were used and the data were analyzed using SPSS win 17.0. Result: Perceived beliefs on EBP were relatively positive (mean score 3.57 out of 5), and the level of knowledge was moderate (4.21 out of 7). However, performance of EBP was low (3.82 out of 7). Regularity in reading research journals and searching evidences using core web-database were rarely conducted. Statistically significant correlations were found between beliefs, knowledge and performance of EBP (all p<.05). Conclusions: This result indicates that education and training programs to facilitate EBP performance are needed among preceptor nurses.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.403-412
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• 2020

The main purpose of this paper is to explore how green supply chain management (GSCM) and its evaluative factors have affected green supply chain management practice and performance in industrial zone. This study proposes a structural equation model of the relationships among four factors: internal awareness (IA); suppliers' pressure (SP); customers' awareness (CA); and regulations pressure (RP) and their effect on GSCM practice (PA) and GSCM performance (PE). We used a survey questionnaire to elicit perceptions/opinions about GSCM from three level of managers of 322 companies in Bac Ninh Province's industrial zones, Vietnam. PLS-SEM 3.0 software was applied to analyze and verify the gathered data, and the proposed hypothesis model. The results of path analysis show that internal awareness and customers' awareness are positively related to the GSCM practice and GSCM performance. However, suppliers' pressure and regulations pressure just impacted on GSCM practice. As a result, the testing of the relationship between GSCM practice and GSCM performance has been verified and supported. The findings of this study can help manager of companies in industrial zone understand the structure of GSCM, associate with the green supply chain management practice and green supply chain management performance, and be successful in green management organizations.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.1
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• pp.1-7
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• 2017

Most conventional processors execute program instructions in a sequential manner. On the other hand, VLIW processor can execute multiple instructions at the same time. It exploits instruction level parallelism to improve system performance. To that end, program code should be rearranged to VLIW instruction format by a compiler. The compiler determine an optimal execution order of instructions of a program code. This instruction ordering is also called instruction scheduling. The scheduling is an algorithm that decides the execution order for instruction codes in loop parts of a program so that the instruction level parallelism can be maximized. In this research, we apply an existing scheduling algorithm to a VLIW FCC and describe analysis results to further improve its performance. And, we present a solution to solve some limitation of the existing scheduling technique. By using our solution, FCC's performance can be improved upto 32% compared to the existing scheduling only setting.

• Nuclear Engineering and Technology
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• v.39 no.6
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• pp.737-746
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• 2007

A spacer grid, which is one of the most important structural components in a PWR fuel assembly, supports its fuel rods laterally and vertically. Based on in-house design experience, scrutiny of the design features of advanced nuclear fuels and the patents of other spacer grids, KAERI has devised its own spacer grid shapes and acquired patents. In this study, a performance evaluation of KAERI's spacer grid shapes was carried out from mechanical/structural and thermohydraulic view points. A comparative performance evaluation of commercial spacer grid shapes was also carried out. The comparisons addressed the spring characteristics, fuel rod vibration characteristics, fretting wear resistance, impact strength characteristics, CHF enhancement, and the pressure drop level of the spacer grid shapes. The results show that the performances of KAERI's spacer grid shapes are as good as or better than those of the commercial spacer grid shapes.

• Journal of Korean Society for Quality Management
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• v.30 no.2
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• pp.11-25
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• 2002

This paper is to find how does service orientation of organization and human resource job satisfaction affect its customer orientation, that is, its service attitude and behavior toward customer. Purpose of this study is also to measure the level of employees' customer orientation more systemic. Consequently, the correlation between service orientation and performance can be identified and more effective guideline for service quality management can be draw through this study. The findings of this paper are as followings; Firstly, it is found that reward system and CEO's vision toward service orientation affect employee's job satisfaction positively, It's analyzed on Gap analysis model of PZB. Secondly, in point of inner marketing, employee who is satisfied with his job shows higher customer orientation. Thirdly, strategy change of organization in response to environment change in hospital industry influences on performance positively.