• 한국기계가공학회지
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• 제16권4호
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• pp.38-45
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• 2017

A finite element analysis-based approach which investigates the causes of the breakdown in the outer ring of the choke at hot rod rolling mill is presented. Two-dimensional drawings of the whole vertical-type mill stand are transformed into three-dimensional CAD models. Non-linear elasto-plastic deformation analysis of material at the roll gap is performed for computing roll force and torque of the work roll. Then, the reaction forces of the bearing rings together with a set of roller bearings that support the work roll are obtained by means of rigid body motion analysis. Finally, stress behaviors in the bearing rings together with a set of roller bearings that support the work roll are investigated by linear elastic analysis. Results reveal that stress at the contact area between the outer ring and roller bearing is extraordinary high when an internal gap between an external surface of the outer ring and the internal surface of the chock due to wear of the inside of the chock occurs.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.3707-3720
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• 2010

본 연구에서는 리더십이 조직유효성에 어떤 과정을 거쳐서 영향을 미치는지 알아보고자, 변혁적 리더십의 하위요인들을 독립변수로 놓고, 조직유효성의 하위요인들을 종속변수로 설정하면서, 조직(직장)에서 가장 중요한 사람과 일에 대한 관계 중 리더에 대한 조직구성원의 관계를 신뢰로 설정하고 조직구성원과 일의 관계를 자기효능감으로 설정하면서 이 두 요소가 어떻게 작용을 하는지 조사하였다. 검증 결과 독립 변수들의 하위요인들 모두가 신뢰에 영향을 주었고, 그 신뢰는 조직유효성에 정의 영향을 미치고 있었다. 그러나 변혁적 리더십의 모든 하위요인들은 자기효능감에는 유의한 영향을 주지 못하였다. 그러나 신뢰가 자기효능감에 영향을 주었고, 그 결과 자기효능감은 조직유효성의 모든 하위요인들에 정의 영향을 미치는 것으로 분석되었다.

• Journal of Information Technology Applications and Management
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• 제25권3호
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• pp.55-66
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• 2018

Early smart-work of company K was a technology-led way of applying ICT such as smart phones and mobile devices to business. After company K perceived the limitations of ICT-driven smart work, it propelled the work-smart, doing a work smart toward the way that human beings become central and a creative organizational culture is engendered. Company K propelled work-smart strategy in eight categories: simplification of data requirements, establishment efficient meeting culture, streamlining reporting and approval process, simplified document creation, overtime decrease, spreading flexible work system, settlement of healing leave, creating work-smart place. Company K set up an organizational culture secretariat dedicated to work-smart promotion and selected task priorities in consideration of urgency and effectiveness. Owing to such efforts, the company K's work-smart index rose sharply to 72 points this year from 56 points in the previous year. At the organizational culture survey, employees responded that organizational culture improved in all area. For a better future, company K analyzed its work-smart outcomes and planned progressively to improve its work-smart efforts based on employees opinions. This case study will serve as a guideline, for companies to make efforts to going forward to today work-smart beyond yesterday smart-work.

• 경영과학
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• 제13권2호
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• pp.25-48
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• 1996

Mixed Model Assembly Lines (MMALs) are increasingly used to produce differentiated products on a single assembly line without work-in-process storage, Usually, a typical MMAL consists of a number of (1) stations doing exactly the same operation on every job, (2) stations involving operations with different choices, and (3) stations offering operations that are not performed on every job, or that are performed on every job but with many options. For stations of the first type there is no sequencing problem at all. However, for the second type a set-up cost is incurred each time the operation switches from one choice to another. At the third type of stations, different models, requring different amounts and choices of assembly work, creates an uneven flow of work along the line and variations in the work load at these stations. When a subsequence of jobs requires more work load than the station can handle, it is necessary to help the operations at the station or to complete the work elsewhere. Therefore, a schedule which minimize the sum of set-up cost and utility work cost is desired. So this study has developed Fixed Random Ordering Rule (FROR), Fixed Ascending Ordering Rule (FAOR), Fixed Descending Ordering Rule, and Extended NHR (ENHR). ENHR is to choose optimal color ordering of each batch with NHR, and to decide job sequence of the batch with it, too. As the result of experiments, ENHR was the best heuristic algorithm. NHR is a new heuristic rule in which only the minimum addition of violations from both partial sequence and unassigned sequence at every branch could be considered. And this is a heuristic sequencing rule for the third type of stations at MMAL. This study developed one more heuristic algorithm to test the performance of NHR, which is named as Practical Heuristic Rule (PHR).

• 산업경영시스템학회지
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• 제23권57호
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• pp.1-10
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• 2000

The purpose of this paper is to propose a method of rest to reduce work load of night shift workers for night shift work. The experiment was carried out 10minutes preparing time, 45minutes first work, 10minutes first rest, 45minutes second work, 10minutes second rest between 2 and 4 o'clock that the lowest physiological function of workers. The methods of rest set up as four patterns (1) non-action rest (2) non-action rest + listening music (3) action rest + non-action rest, (4) action rest + non-action rest + listening music. For the measurements of experiment, heart rates(R-R interval), critical flicker fusion frequency(CFF), blood pressure, oral temperature, reaction time and error rates were considered as criteria for work performance. As a result, action rest + non-action rest and action rest + non-action rest + listening music were more effective to reduce work load additional work than non-action rest and non-action rest + listening music.

• 대한안전경영과학회지
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• 제20권2호
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• pp.55-63
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• 2018

This study empirically verified the effect of enterprise SNS usage on communication and work performance and the effect of communication on work performance for corporate employees. To accomplish the purpose of this study, we proposed a research model, set up research hypotheses, and verified the hypotheses based on previous studies. For this study, we surveyed the employees of manufacturing companies located at Ulsan city. The results of this study are summarized as follows. First, the use of enterprise SNS has a significant effect on communication. Second, communication has a significant effect on work performance. Third, the use of enterprise SNS has a significant effect on work performance. Through the results of this study, it can be confirmed that the introduction and utilization of enterprise SNS suitable for enterprises leads to the satisfaction of employees' communication and improvement of the work performance.

• 패션비즈니스
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• 제8권4호
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• pp.131-140
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• 2004

This study will first take a look at the work situations depending on functions or duties taken in fashion organizations in Busan, dividing the work condition into aspects such as special traits of the work, satisfaction level on the company and satisfaction level on welfare. This study has set the following study questions to reach the goal of this research: 1. look at special traits found depending on vital statistics. 2. The satisfaction level on special traits of the work and work itself showed that the diversity of work, importance of work and work flexibility were the key elements that influenced the satisfaction level. 3. The satisfaction level on company and work itself had pride and loyalty, the only factors that influenced work satisfaction level voluntarily, and the other factors had no effect on the satisfaction level. 4. The satisfaction level on welfare and work itself showed that the welfare benefits and welfare policies had no voluntary influence on the satisfaction level on the work itself.

• ETRI Journal
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• 제34권6호
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• pp.950-953
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• 2012

Schottky barrier single electron transistors (SB-SETs) and Schottky barrier single hole transistors (SB-SHTs) are fabricated on a 20-nm thin silicon-on-insulator substrate incorporating e-beam lithography and a conventional CMOS process technique. Erbium- and platinum-silicide are used as the source and drain material for the SB-SET and SB-SHT, respectively. The manufactured SB-SET and SB-SHT show typical transistor behavior at room temperature with a high drive current of $550{\mu}A/{\mu}m$ and $-376{\mu}A/{\mu}m$, respectively. At 7 K, these devices show SET and SHT characteristics. For the SB-SHT case, the oscillation period is 0.22 V, and the estimated quantum dot size is 16.8 nm. The transconductance is $0.05{\mu}S$ and $1.2{\mu}S$ for the SB-SET and SB-SHT, respectively. In the SB-SET and SB-SHT, a high transconductance can be easily achieved as the silicided electrode eliminates a parasitic resistance. Moreover, the SB-SET and SB-SHT can be operated as a conventional field-effect transistor (FET) and SET/SHT depending on the bias conditions, which is very promising for SET/FET hybrid applications. This work is the first report on the successful operations of SET/SHT in Schottky barrier devices.

• 대한수학회보
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• 제51권3호
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• pp.641-651
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• 2014

Because of difficulty of using Schauder's fixed point theorem to the polynomial-like iterative equation, a lots of work are contributed to the existence of solutions for the polynomial-like iterative equation on compact set. In this paper, by applying the Schauder-Tychonoff fixed point theorem we discuss monotone solutions and convex solutions of the polynomial-like iterative equation on an open set (possibly unbounded) in $\mathbb{R}^N$. More concretely, by considering a partial order in $\mathbb{R}^N$ defined by an order cone, we prove the existence of increasing and decreasing solutions of the polynomial-like iterative equation on an open set and further obtain the conditions under which the solutions are convex in the order.

• 한국경영과학회지
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• 제17권1호
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• pp.43-54
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• 1992

This paper discusses a real time production control system of a FMS (Flexible Manufacturing System). The control is organized in a hierarchical structure according to the various decisions at the different time scales. In the earlier work-set-up time was not considered. Because the capacity of the toll magazine is limited, this assumption may not be adequate for selecting times to change configurations so that new part family can be produced. The goal of the control system is to meet production requirements while the machines fail and are repaired at random times. In this thesis the machien failure and set-up are considered simultaneously. Here the hedging point of this system is calculated, and the formulation of the dynamic control for FMS that has unreliable machines with set-up suggested.