• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.10
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• pp.1045-1052
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• 2015

In this paper, a stabilized control algorithm for the large rotating stand of a long-range surveillance radar (LRSR) system is introduced. The stabilized control algorithm for this large rotating stand system was designed using mathematical plant modeling. The LRSR system is located on high ground and has a wide surface, making it susceptible to the effects of wind, which increases the bearing friction and reduces the stability of the rotating stand. The disturbance caused by the wind was analyzed using computational fluid dynamics (CFD) in this study. The results of the CFD analysis were used to construct a control algorithm for the disturbance . The performance of the proposed control algorithm was demonstrated experimentally and through simulations. The plant model and the control algorithm were constructed in Matlab/Simulink.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.3
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• pp.457-474
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• 2002

Purpose : The purpose of this study was to construct the Organizational Effectiveness Model that explains and predicts the effectiveness of a nursing unit from the organizational-behavioral perspective. Furthermore, this study arms to develop a comprehensive organizational effectiveness model. Method : The subjects of this study consist of two groups: 455 nurses and 538 patients. Staff nurses who were employed and twenty patients from each ward in four university hospitals located in Seoul, Pusan and Kyungki were involved. Data were collected from October 4th to October 14th in 2000 by self-report questionnaire. Data were analyzed by the SAS for the general characteristics of the subjects, descriptive statistics, test for the reliability and correlations. Fitness of the hypothetical model were tested using Lisral 8.12(a) program. Result : With the findings from this study, duration of employment and the locus of control among the characteristics of the nurses, job enrichment among the characteristics of nursing job were direct or indirect predictors of the organizational effectiveness of the nursing units. Group dynamics in the nursing units and the characteristics of organizational behavior were mediating variables for the organizational effectiveness of the nursing units, and affect directly and indirectly on the individual outcome and group outcome to the great extends. Conclusion : Therefore, nursing managers ought to develop career ladder program and based job enrichment program in order to improve the organizational effectiveness of the nursing units. Additionally, programs to improve organizational effectiveness via improve group dynamics and characteristics of the organizational behaviors should be developed.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.2
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• pp.208-216
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• 2019

Objective: The aim of this study is to control residual chemicals or by-products generated in chambers during preventive maintenance (PM) in the semiconductor manufacturing industry. We designed local exhaust ventilation using computational fluid dynamics (CFD). Methods: The air flow characteristics and capture efficiency between rectangular and slot hoods were compared numerically. The software Fluent 18.1 was used to estimate uniform velocity distribution and capture efficiency for contaminants. A metal from group 15 in the periodic table was released at the bottom of the chamber to simulate emissions. Results: The slot hood had a higher capture efficiency than a rectangular hood under the same conditions because the slot hood provided uniform air flow and higher face velocity. Also, there was no rotating swirl in the plenum for slot, that is why slot had better efficiency than rectangular even though they had similar face velocity. With less than 10 slots, the capture efficiencies for contaminants were nearly 95%. The optimum conditions for a hood to achieve high efficiency was 8 to 10 slots and a face velocity over 1 m/s. Conclusions: Well-designed ventilation systems must consider both efficiency and convenience. For this study, a slot hood that had high capture efficiency and no work disturbance was designed. This will contribute to protection of the worker's health in a PM area and other areas as well. Also, this study confirms the possibility of the application CFD in the semiconductor fabrication industry.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.79-90
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• 2023

Leadership development corresponds to the focus on the individual's success and competitiveness strategy. This is the optimal direction of the organization of attitude development because it covers two aspects of the student's personality development, professionally-oriented and self-centric. The aim of the study is to identify and compare the leadership level in second-and fourth-year students to see dynamics of development and implementation of the leadership phenomenon in the professional and personal making up of future specialists. Based on the theoretical analysis of the issue, the authors developed an objective and subjective diagnostic model for leadership skills. In this study, data of the objective diagnostic technique are the key. Subjective diagnostic technique for leadership skills provides insights for problem interpretation. At the level of the first group of respondents, the average Leadership Skills Level of the second-year students was quite low and was found within the medium level. The second group of respondents consisting of the fourth-year students showed a slight but effective improvement. The Leadership Skills of this group were found at a sufficient level. Positive dynamics was revealed for all criteria of leadership skills as a result of applying objective diagnostic methods: decreased percentage of students with negative and relatively low markers of Leadership Skills Level and corresponding increase in percentage of applicants with positive markers of Leadership Skills Level. Further research can be organized in the direction of identifying and developing successful universal and professionally-oriented tactics for leadership development in students as part of attitude development.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.359-366
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• 2013

Although many research efforts have been conducted to address the effect of crew members' work skills (e.g., technical and planning skills) on work performance (e.g., work duration and quality) in construction projects, the relationship between skill and performance has generated a great deal of controversy in the field of management (Inkpen and Crossan 1995). This controversy can lead to under- or over-estimations of the overall project schedule, and can make it difficult for project managers to implement appropriate managerial policies for enhancing project performance. To address this issue, the following aspects need to be considered: (a) work performances are determined not only by individual-level work skill but also by the group-level work skill affected by work team members, each member's role, and any working behavior pattern; (b) work planning has significant effects on to what extent work skill enhances performance; and (c) different types of activities in construction require different types of work, skill, and team composition. This research, therefore, develops a system dynamics (SD) model to analyze the effects of both individual-and group-level (i.e., multi-level) skill on performances by utilizing the advantages of SD in capturing a feedback process and state changes, especially in human factors (e.g., attitude, ability, and behavior). The model incorporates: (a) a multi-level skill evolution and relevant behavior development mechanism within a work group; (b) the interaction among work planning, a crew's skill-learning, skill manifestation, and performances; and (c) the different work characteristics of each activity. This model can be utilized to implement appropriate work planning (e.g., work scope and work schedule) and crew management policies (e.g., work team composition and decision of each worker's role) with an awareness of crew's skill and work performance. Understanding the different characteristics of each activity can also support project managers in applying strategic work planning and crew management for a corresponding activity, which may enhance each activity's performance, as well as the overall project performance.

• Journal of the Korean Magnetic Resonance Society
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• v.13 no.1
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• pp.35-55
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• 2009

The two correlation times previously obtained in our coupled $^{13}C$ relaxation measurement for the methyl group in 2,6-dichlorotoluene may be used as a criterion for evaluating the reorientation dynamics of an internal rotor. We numerically tested an extended diffusion model and the Smoluchowski diffusion equation to see how the rotational inertial effect and jump character contribute to the internal correlation time ratio of the internal rotor. We also analytically solved the general jump model with three different rate constants in a sixfold symmetric potential barrier. By assuming that the internal rotation of the methyl group in 2,6-dichlorotoluene can be described in terms of jumps among sixfold harmonic potential wells, we can conclude that the jump model satisfactorily reproduce the experimental data and the rate for sixfold jump is at least 1.53 times as great as that of a threefold jump.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.91-98
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• 2015

Formamide의 중성가수분해 mechanism은 QM/MM (quantum mecahnics/molecular mechanics) molecular dynamics simulations 및 CPMD과 같은 방법으로 연구되어왔다. 본 연구에서는. Umbrella sampling을 이용한 QM/MM-MD simulation을 사용하여 4가지 반응의 free energy surface를 도출해냈다. 전체적으로, 가장 선호되는 메커니즘은 two step으로 구성된 water assisted stepwise mechanism이었으며 모든 mechanism은 ab-initio calculation과 QM/MM-MD simulation이 수행되었다. water assisted stepwise mechanism을 살펴보면, 첫 번째 step에서 formamide의 carbonyl group이 hydrate되면서 gem-diol intermediate를 형성한다. 다음 step에서, intermediate의 hydroxyl group으로부터 amino group으로 water-assisted proton transfer이 일어난다. 두 반응 모두에서 물이 proton transfer를 직접적으로 도와주는 것을 관찰할 수 있었다. 특히, ab-initio calculation과는 다르게 QM/MM-MD에서는 gem-diol intermediate가 안정화되는 것으로 solvent effect를 잘 보여준다.

• Asia Marketing Journal
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• v.22 no.4
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• pp.103-116
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• 2021

This research outlines the motivations behind the fan-lead marketing and promotional endeavours undertaken by musical group BTS's fan community, also known as ARMY. In highlighting the reciprocity in intimacy between the group and their fans, I argue that ARMY's desire to elevate BTS is embedded within structures of affect, despite the financial nature of the benefits the group and their company may reap. These fan-lead initiatives represent efforts towards a common goal, where success, whether it comes in the form of money or not, is a gift of gratitude and a show of mutual understanding from fans to BTS. Based on data from 22 interviews with fans, this research explores the motivations behind fan-lead marketing by looking at the affective properties of music consumption, the parasocial relationship, fan community dynamics, and the purchase of intimacy. Within these contexts, the promotion surrounding BTS's music, as organized by the fans, mimics profit-oriented behaviours but is ultimately a gesture towards the exchange of intimacy between fans and artist.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.1
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• pp.19-28
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• 2020

Ranciéte is a hexagonal phyllomanganate mineral containing random Mn(IV) vacancies with hydrated Ca²⁺ cations charged balanced as interlayer cations. Its Mn²⁺ analogue is called takanelite, and ranciéite and takanelite are regarded as end-members of a solid solution series of (Ca²⁺,Mn²⁺)Mn₄O₉·nH₂O. Because the minerals are found as very small particles associated with other minerals, the crystal structures of the solid solution series have yet to be defined. In this research, we conducted classical molecular dynamics (MD) simulations of ranciéite and takanelite by varying the Mn²⁺/Ca²⁺ interlayer cation ratio to find relations between the interlayer cations and mineral structures. MD simulation results of chalcophanite group minerals are compared with experimental results to verify our method applied. Then, lattice parameters of ranciéite and takanelite models are presented along with detailed interlayer structures as to the distribution and coordination of cations and water molecules. This study shows the potentials of MD simulations in entangling complicated phyllomanganates structures.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.339-347
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• 2013

Recently, Korean medium-sized medical organizations require innovative strategies. Network-driven concerns in Korean medical organization have been a front burner issue to enhance economic and managerial efficiencies. Effective network-driven collaboration depends upon effective processes and economics strategies among medical providers group. From this motivation, we studied and provided the systems' theoretical background and networked hospital system structures. The aim of suggested research model in this paper is to overcome demerit of stand-alone medium-sized hospitals and analyze a system dynamics model to measure managerial performances. The developed system dynamics model is to quantify the effects of network strategy based on the historical financial data of real-life hospitals network experiences. The network effects are resulted in efficiencies and effectiveness enhancements in competitiveness through advertisement and effective education system. The simulations of system dynamics results can explain the improvement in financial outcome by joining in the network group. The network effects are shown more effective in dental hospital than other groups. In conclusion, it is expected that network effects have a critical influence of managerial, marketing, and medical collaboration performance for any type of medical hospitals.