• Design & Manufacturing
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• v.16 no.3
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• pp.39-43
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• 2022

In this study, we designed an vibration cutting tool that can achieve improvements such as low cutting force, interrupted chip evacuation and better surface quality of cutting performance to obtain high-quality surface roughness and improvement of tool wear, which is an issue in the machining of high-hardness mold steel. Among the resonance frequency modes of the vibration cutting tool, the bending mode was used to maximize the driving amplitude of the vibration tool tip, and the resonance frequency was confirmed through the finite element method. After measuring the actual resonant frequency of the designed tool using an optical fiber sensor, the cutting force and machining surface of vibration cutting and conventional cutting were compared and analyzed in the turning process of high hardness mold steel (STAVAX). As a result of the experiment, the cutting force was reduced by about 20 % compared to the conventional cutting process, and the surface roughness was also improved by about 60 %. This study suggested that the tool wear and surface quality of high-hardness steel can be improved through the vibration cutting method in the machining of high hardness mold steel.

• Journal of Drive and Control
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• v.19 no.2
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• pp.17-26
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• 2022

Recently, automatic transmissions caused a good improvement in the shift quality of a forklift. An advanced shift control algorithm, which was based on TCU firmware, was applied with embedded control technology and microcontrollers. In the clutch-to-clutch shifting, one friction element is released and the other friction element is activated. During this process, if the release and application timings are not synchronized, an overrun or tie-up occurs and ultimately leads to a shift shock. The TCU, which measures only the speed of the forklift, inevitably applies the open-loop shift control. In this situation, the speed ratio does not change during the clutch fill. The torque phase occurs until the clutch is disengaged. In this study, an offline shift logic of the learning control was proposed. It induced a synchronous shift when the learning control progressed. During this process, the reference current trajectory of the release clutch was corrected and applied to the next upshift. We considered the results of the overrun/tie-up characteristics of the upshift performed immediately before. The vehicle test proved that the deviation in shift quality, which was caused by the difference in the mechanical characteristics of the clutch, could be improved by the learning control.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.177-182
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• 2023

Iron (Fe) is a vital element for plants and other organisms, involving in several physiological processes including respiration, chlorophyll biosynthesis, and photosynthesis. Unfortunately, how Fe accumulation regulates in response to light quality has not been well established in plants. Therefore, the aim of the study was to explore the mechanism of Fe homeostasis by light quality. In this study, we found morpho-physiological attributes were significantly improved in response to blue (λmax: 450) compared to white (λmax: 500) and red (λmax: 660) light. The root-shoot length, plant biomass, photosynthesis efficiency (Fv/Fm) and leafgreen (SPAD) significantly declined in response to white and red light. However, these parameters were improved and iron deficiency was substantially alleviated by blue light exposure in alfalfa seedlings. This study might be useful to the forage breeders and farmers for improving alfalfa yield and nutritional benefits.

• Proceedings of the Korean Society for Quality Management Conference
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• 2007.04a
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• pp.70-75
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• 2007

The university organization is getting more and more complicated both in function and size these days, and the particularity of university organization inherently has quite a few element of internal conflict. To cope with the rapidly changing university society, together with the all-out effort of university CEO, it is necessary to pay attention to the administrative employees who can really contribute to the organizational competitiveness a lot. The Service Quality Management provides the action guidelines to every individual members of organization and alternatives to the problems the organization is facing. According only Service Quality Management can improve the efficiency of the organizational management and the job efficiency of individual members. Thus, in actual proof researching, we conduct and analyze how the university industries do Service Quality Management such as 6 sigma through survey researching.

• Korean Journal of Computational Design and Engineering
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• v.17 no.3
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• pp.164-174
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• 2012

The recent introduction of BIM technology has raised the interest on the BIM quality assurance and management more than ever. This study aims to consider the ways of BIM quality improvement by analyzing the most frequent issues rising from multiple BIM projects. For this purpose, the 12 test models from BIM education program hosted by buildingSMART Korea are investigated based on the requirements in the public BIM guidelines. All the BIM issues generated are categorized by the criteria applied and analyzed for each kind of building element. The results showed that more than half of the issued at least could be cleared out by improving modeling habits and technical guides.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.252-254
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• 2015

Building Information Modeling (BIM) encourages effective information share and utilization among project participants during entire life cycle of facility. This paper presents a method that keeps track of the historical quality records involved in construction operations and facilitates using BIM. The method is coded into BIM based Quality Record Traceability (BIM-QRT) System that makes use of historical records obtained from database administrating construction operations. This study is of value to practitioners because the method makes clear the project participants' responsibility relative to the quality of each and every element of the facility. The main objective of this research is to develop an accurate, fully automated method for construction Quality Record Tracking by using a BIM along with construction operations data obtained by information technology. Test cases verify the usability and validity of the methods implemented in the system.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.6
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• pp.1039-1049
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• 2017

This study investigated the effect of shopping satisfaction on travel satisfaction, travel specific quality of life and overall quality of life for Korean vacation tourists. Tourist evaluations on those four variables were confirmed first. The effect of shopping satisfaction on the other variables was then investigated. The effect of demographics was also identified. An on-line survey method was used to obtain data of 20's-50's tourists, while factor analysis, regression analysis, ANOVA, and Duncan test were applied to analyze data. The results were as follows. First, shopping satisfaction of the vacation travel showed a positive effect on tour satisfaction, which affected the quality of life after travel. Second, travel specific quality of life had a significant effect on overall quality of life and confirmed the bottom-up spillover effect. Third, the perception of shopping satisfaction, travel satisfaction, travel specific quality of life, and overall quality of life differed by demographic factors. Women and young tourists revealed high satisfaction scores in shopping and travel; in addition, wealthy travelers showed a higher quality of life. Occupation tended to partly affect satisfaction and quality of life. The findings implied that travel and tourists' shopping are an important element to enhance the quality of life.

• Asia Marketing Journal
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• v.1 no.3
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• pp.53-78
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• 1999

Despite of the vibrant nature of the fitness industry, there has not been a sustained effort to understand the dynamics of the industry, particularly with reference to the quality of services offered in that industry. The purpose of this paper is to present a system based process model of quality in health/fitness services. The characteristics of the organization, the service employees and the client are the inputs into the service encounter where the service is produced (i.e., the throughput). The output is the quality of the service. The extent of quality perceived by both the service provider and the client is said to influence the satisfaction of the respective parties, and subsequent motivation to participate in the production of quality in the service. The model also suggests that physical environment as well as other customers and their behaviors influence customer perception of service quality. The quality of service is enhanced through the quality assurance practices of the organization and the feedback from client. Further, the input, throughput, and output in our model reflect (a) quality of the design of the service delivery system, (b) objective quality of the product, and (c) quality as perceived by client. The specific attributes of the design element (i.e., organization, service employee, and the client) are elaborated upon. It is suggested that the organization can assure quality by seeking feedback from clients and service employees, monitoring the service production phases, and managing inter-customer interactions.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.288-295
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• 2003

An adaptive procedure in finite element analysis is presented by p-refinement of meshes in conjunction with a posteriori error estimator that is based on the recovery technique. In case of the recovery technique, the SPR(superconvergent patch recovery) approach has been modified for p-adaptive mesh refinement. The strategy of finding a nearly optimal distribution of polynomial degrees on a fixed finite element mesh is discussed such that a particular element has to be refined automatically to obtain an acceptable level of accuracy by increasing p-levels non-uniformly. To verify the proposed algorithm, the limit value approach is proposed which utilizes the exact strain energy computed from the extrapolation equation. A new pre-processor is developed for the p-version finite element program in which the vector graphic editor is used for the automatic generation of node connection and coordinate by halfedge solid data structure according to uniform or nonuniform p-distribution. The general 2-D algorithm is also developed to generate face modes and internal modes in accordance with different mesh types. The quality of the error estimator is investigated with the help of two mumerical examples. The results show that the sequences of p-distributions obtained by the proposed error indicator closely follow the optimal trajectory.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.166-171
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• 2001

In order to improve the efficiency of the design process and the quality of the resulting design for the application-based exclusive rolling element bearings, this study propose design methodologies by using a genetic-based combinatorial optimization. By the presence of discrete variables such as the number of rolling element (standard component) and by the engineering point of views, the design problem of the rolling element bearing can be characterized by the combinatorial optimization problem as a fully discrete optimization. A genetic algorithm is used to efficiently find a set of the optimum discrete design values from the pre-defined variable sets. To effectively deal with the design constraints and the multi-objective problem, a ranking penalty method is suggested for constructing a fitness function in the genetic-based combinatorial optimization. To evaluate the proposed design method, a robust performance analyzer of ball bearing based on quasi-static analysis is developed and the computer program is applied to some design problems, 1) maximize fatigue life, 2) maximize stiffness, 3) maximize fatigue life and stiffness, of a angular contact ball bearing. Optimum design results are demonstrate the effectiveness of the design method suggested in this study. It believed that the proposed methodologies can be effectively applied to other multi-objective discrete optimization problems.