• 한국환경과학회지
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• 제25권9호
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• pp.1283-1288
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• 2016

In this study, we synthesized fluorescent sensors from rhodamine 6G derivatives and hydroxy coumarin. The synthetic routes to the rhodamine 6G derivatives containing hydroxy coumarin are shown in Fig. 1. Two derivatives were synthesized through Schiff base reactions. The structures of the new compounds were confirmed by melting point, $^1H$-NMR, and GC-MS analyses. The compounds were found to selectively bind to tin ($Sn^{2+}$) ion by fluorescence titration using various metal cations. Longer carbon chains gave more sensitivity. $Sn^{2+}$ ions exhibited the strongest fluorescence among the nime ions. The binding analysis using Job plots suggested that compounds form 1:1 complexes with the $Sn^{2+}$ ions.

• 산업공학
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• 제21권3호
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• pp.333-342
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• 2008

Warehouses form an important link in a supply chain network. Among a variety of activities in warehouses, order picking is the process of retrieving a number of items out of storage to meet customer orders. Today, as the transactions through direct sales are wide spread, warehouses often receive a large amount of small orders to be handled within tight time windows, which makes fast and efficient order picking more important than ever. This paper examines a new order picking method where the concept of bucket brigade (BB) is applied. Bucket brigade is a way of dynamically coordinating workers who progressively perform a set of operations along a flow line. In bucket brigades, a worker is not assigned his jobs in a static way. Each worker takes a job from his predecessor when he is free. We identify some considerations when bucket brigades are applied to order picking activities. A new BB picking protocol is presented to improve existing BB picking protocols. Through simulation experiments, the performance of BB order picking is evaluated under various logistics environments.

• 대한가정학회지
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• 제37권12호
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• pp.13-28
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• 1999

This study aimed to analyze the process of courtship form having date and marriage toward women who had job before marriage. The objects were 27.36 years old and had 9.59 months marital life at average. This study conducted structured questionnaires using the reflection of spouse selection procedure. By using collected data through questionnaires, it conducted descriptive statistics, cluster analysis and t-test. The type of marriage would be divided into the emotional marriage group and the implemental marriage group The emotional marriage group had longer dating time and more satisfaction of spouse selection than the implemental group. On value variable, the emotional marriage group had more subjective selection standard and more expectation social and emotional benefit than the latter group. On search variable, the emotional marriage group estimated the relation stability and satisfied the relation with spouse more than the implemental marriage group and expected the less possibility to meet new partner.

• 한국생산제조학회지
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• 제7권2호
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• pp.69-73
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• 1998

With increased loads in steered wheels and wider section tires the effort required at the steering wheel makes the driver's job very tiring and difficult. Improvements such as an increase in the mechanical efficiency of the steering system or lower steering box ratios help the reduce driver fatigue. Now using of power steering is increasing. It needs to be considering parts size of steering system as using power steering. This paper presents adjust part size of steering system form estimating reliability according to reducing torque under the dynamic load, In this paper, the spider of universial joint is selected to prove relation between steering and power steering reliability.

• 간호행정학회지
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• 제13권3호
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• pp.302-310
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• 2007

Purpose: This study was designed to identify clinical competence and education needs of hospital nurses. Method: A questionnaire was used for data collection which was done form July 1 to July 30, 2005. The respondents were 165 staff nurses in a university hospital. The study instrument were clinical education need scale and Lee(2002)'s clinical competence scale. The data were analyzed using percentages, means, t-test, ANOVA with SPSS-WIN 10.0 program. Result: The results of this study are summarized as follows: The total mean score for clinical competence was 2.57 and education need was 3.30 on a 4 point scale. There was a significant difference in clinical competence according to individual factors of age, marital status, preceptorship experience, present ward, job satisfaction, and total clinical experience. also there was a significant difference in education needs according to preceptorship experience and present ward. Conclusions: Conducting a education needs and clinical competence assessment can provide valuable information that will plan education program and improve staff competence.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.175-182
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• 2001

Effective length factor approach for framed column design has long played an important design-aid role. This approach, however, is effective only when the columns are in the form of prismatic or uniform cross sections. Structural engineers who have to design or analyse framed columns with variable cross sections need some means to do their job. By using the finite element method, the stability analysis of the isolated compression members with variable cross sections and that of the framed columns are performed. The parameters considered in the stability analysis are taper and sectional property parameters of the columns, the second moment of inertia ratio of beam to column, and beam span to column height ratio. On the basis of the stability analysis results, effective length factor formulas for the columns with variable sections are derived.

• 한국경영과학회지
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• 제25권1호
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• pp.37-50
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• 2000

We are concerned with estimating the average performance of a re-entrant line with single-job machines and batch machines. The system has multiclass jobs, which will be processed in predetermined routes. An analytical approach may be intractable since the system would not be modeled by product form queueing networks due to the inclusion of batch machines and the consideraton of multiclass jobs which have different processing times. We propose an approximation method based on the Mean Value Analysis(MVA). Our method obtains the mean walting time in each buffer of a workstation and the mean cycle time using the MVA and heuristics. numerical experiments show that the errors of our method are within 5% compared with simulation.

• 대한산업공학회지
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• 제17권2호
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• pp.63-74
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• 1991

An expert scheduling system on real time basis for computer-aided manufacturing systems has been developed. In developing expert scheduling system, the most time-consuming job is to obtain rules from expert schedulers. An efficient process of obtaining rules directly form the schedules produced by expert schedulers is proposed. By the process, a set of complete and minimal set of rules is obtained. During a real time scheduling, when given information on possible values of elements, the rules produce possible values of decision elements, where logical explanations of the result may be offered in terms of chaining rules. The learning and scheduling processes have been simulated with an automated manufacturing line engaged in the production of circuit boards.

• 경영과정보연구
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• 제25권
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• pp.143-169
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• 2008

The purpose of this paper is to propose alternatives to help for the aged to implement start business as a method to recreate the aged population for their second life. There are three considerations that supports start business for the elderly. The first is to reinforce educational support system for the aged. Through the lifelong education, the aged require easy start business' information. This is not only goverment's job, a local autonomous entity is to support in the form of organic organization. The second is the maintenance of financial support system. Besides start business education, various financial support system must serve for the aged to challenge their start business enthusiastically. The last consideration is formation of start business network that joins the aged efficiently. Based on these aspects, the application for increasing elderly human resource is to consider both employment program of the aged and also start business program for them.

• 산업경영시스템학회지
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• 제23권54호
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• pp.77-85
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• 2000

One form of job shop scheduling problem in contemporary automated manufacturing such as flexible manufacturing systems (FMS's) is presented which we call the FMS dispatching priority problem. The FMS dispatching priority problem seeks the best dispatching priority of parts and operations, and is essentially a combinatorial optimization problem. Because of the complicated mechanism of the system, the performance of a given dispatching priority must be evaluated via simulation. Simulated annealing have been applied to the problem, and it is found that appropriate parameter setting will be desirable to get good, if not the optimal, solutions within a limited amount of time under the presence of heavy computational burden due to simulation. More specifically, experiments reveal that initial temperature is the single most important factor among other parameters and factors, and that the appropriate initial temperature depends on the allowable computer time in such a way that the less time one can afford to spend, the lower the appropriate initial temperature should be.