• Journal of Biosystems Engineering
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• v.36 no.4
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• pp.257-266
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• 2011

Consumption of chicken feet has been increasing recently, thus it was necessary to produce good quality of bone less chicken feet. In the process of bone removal during chicken feet production, feeding, conveying, cutting and bone removing process takes about 90% of overall labor. Therefore, the development of a chicken feet-bone remover was necessary to reduce the cost of labor. The main objective of this study was to make and test of chicken feet-bone remover. The optimum vibration level of feeder wes 8, and the optimum conveyor speed was 3.6 m/min. The feeding speed of feeder were 0.18 m/s, 0.13 m/s and 0.19 m/s for the weight ranges of chicken feet of >20 g, 20~30 g and 30 g< respectively. The sensing success rates of chicken feet were 100%, 98% and 96% for the conveyor speeds of 3.0, 3.6 and 4.2 m/min respectively. The slips of chicken feet were 1.0 mm, 1.9 mm and 3.2 mm for conveyor speed of 0.8, 1.9 and 4.2 m/min respectively, with the average moisture content of 65% (w.b). The incision accuracy rates of the chicken leg were 46%, 95%, 97% for the size ranges of >15 mm, 15~18 mm, 18 mm< respectively with the velocity of cutting blade 3.9 m/s. The removal rates of the chicken feet bone were 98%, 96%, 88% for toes diameter >10 mm, 10~15 mm, 15 mm> respectively with the velocity of cutting blade 11.8 m/s.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.353-356
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• 2005

In Taiwan, there are more the one hundred GPS tracking stations maintained by Ministry of the Interior (MOI), Academia Sinica, Central Weather Bureau and Central Geological Survey. In the further, they may be instead of the GPS controlling points after giving the lawful status. In other words, the engineers don't need to survey on the reference points when they are surveying in the field. They only need to download the GPS data via internet and process the observations in their company. The precise coordinates of the unknown points will be obtained. Therefore, the data qualities of the tracking stations are more and more important. In this study, six data quality indexes were adopted as follows: observations, cycle slips, multipath on L1, multipath on L2, clock offset and frequency stability. Besides, the relationships of the indexes and the positioning precision were found. The frequency stability of GPS receiver is the most important index, the cycle slip is the second index and the mutlipath is the third index. According to the results, the auto-analytical system of GPS data quality was established and the tracking stations were monitored. When the receiver got some problem or the station's environment changed, we hope to find and resolve the problems earlier to make sure the high data quality of the tracking stations. Moreover, we try to design a data quality verification to help users and let the engineers have more and more confidence when they use the data of GPS tracking stations.

• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.417-430
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• 2007

The selection of ground stations is one of the essential process of IGS (International GNSS Service) products. High quality GPS data should be collected from the globally distributed ground stations. In this study, we investigated an effect of ground station network selection on GPS satellite ephemeris. The GPS satellite ephemeris obtained from the twelve ground station networks were analyzed to investigate the effect of selection of ground stations. For data quality check, the observations, the number of cycle slips, and multipath of pseudoranges for L1 and L2 were considered. The ideal network defined by Taylor-Karman structure and SOD (Second Order Design) were used to obtain the optimal ground station network.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.2 s.5
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• pp.105-113
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• 2002

Steel-Concrete composite girders have been used since early in the 1920's due to their advantages, which are lower weight, increasement of stiffness, slenderness, long span. However, in designing short to continuous composite bridges, negative moment occurs in mid-support and creates problems such as cracks in the concrete slab. Therefore, partially composite bridges are considered. In this time, slab-anchor is used in these. If the stiffness of shear connectors is insufficient, slip would happen at the contact surface. Partial interaction is the case that takes account of slips. In this paper, the evaluation of initial shear stiffness of slab-anchor in composite bridges is obtained from Push-Out specimen. Also, finite element analyses which uses the initial shear stiffness of slab-anchor got the experiment are carried out on simple composite girder and continuous composite girder. Futhermore, the ratio of composite according to various shear stiffness are investigated and the classification according to the ratio of composite is proposed.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.515-528
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• 1995

Slips and falls are the major causes of the pedestrian injuries in the industry and the general community throughout the world. With the awareness of these problems, the friction coefficients of the interface between floorings and footwear have been measured for the evaluation of slip resistant properties. During this measurement process, the surface texture has been shown to be substantially effective to the friction mechanism between shoe heels and floor surfaces under various types of walking environment. Roughness, either of the floor surface or shoe heels, provides the necessary drainage spaces. This roughness can be designed into the shoe heel but this is inadequate in some cases, especially a wear. Therefore, it is essential that the proper roughness for the floor surface coverings should be provided. The phenomena that observed at the interface between a sliding elastomer and a rigid contaminated floor surface are very diverse and combined mechanisms. Besides, the real surface geometry is quite complicate and the characteristics of both mating surfaces are continuously changing in the process of running-in so that a finite number of surface parameters can not provide a proper description of the complex and peculiar shoe - floor contact sliding mechanism. It is hypothesised that the interface topography changes are mainly occurred in the shoe heel surfaces, because the general property of the shoe is soft in the face of hardness compared with the floor materials This point can be idealized as sliding of a soft shoe heel over an array of wedge-shaped hard asperities of floor surface. Therefore, it is considered that a modelling for shoe - floor contact sliding mechanism is mainly depended upon the surface topography of the floor counterforce. With the model development, several surface parameters were measured and tested to choose the best describing surface parameters. As the result, the asperity peak density (APD) of the floor surface was developed as one of the best describing parameters to explain the ambiguous shoe - floor interface friction mechanism. It is concluded that the floor surface should be continuously monitored with the suitable surface parameters and kept the proper level of roughness to maintain the footwear slip resistance. This result can be applied to the initial stage of design for the floor coverings.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.143-147
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• 2006

The rail clamp is the device to prevent that a crane slips along rails due to the wind blast as well as locate the crane in the set position for loading and unloading containers. The wedge type rail clamp should be designed to consider the structural stability and the durability because it compresses both rail side with large clamping force by the wedge working as the wind speed increases. In this research, the kriging interpolation method using sequential sampling is utilized to find the optimum shape of the jaw in the rail clamp. The suggested method predicts more accurate response value than the response surface method. The optimum results obtained by the proposal method are compared with those by the commercial software.

• Korean Journal of Health Education and Promotion
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• v.20 no.3
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• pp.91-108
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• 2003

Psychological stress is a growing issue in work stress research because work stressors are closely related to depression； and depression, in turn, decreases organizational effectiveness. Considering such causal relationships of work stress, a comprehensive source to control work stress is needed for worksite mental well-being. This study was conducted to identify how social support at work controlled work stress and which characteristics of social support were effective on work stress reduction. The study participants were 240 workers employed in a public hospital in Georgia, U.S.A self-administered survey was given to employees with their pay slips, and followed by a hospital wide voice reminder for 7 days. Surveys were conducted over a 20-day period. The questionnaires asked about job demands, job control, social support at work, depression, job performance, absenteeism, and demographics. The social support construct was structured on the source of support at work and the kinds of support were provided. Statistical analyses were conducted in the structural equation modeling approach. Social support at work was directly related to high job control, low depression, and high job performance. High score of social support at work were significantly associated with high job control, low depressive symptoms, and high job performance. By source of support, only organizational support was positively related to high job control. Organizational support was more effective than supervisor and coworker support. Any stressors and their outcomes were not differenciated by the kinds of support. This result indicated that job control was influenced more by the source of support than the kinds of support provided at work； and the most efficient source of support was the organization. Organizational support was a strong factor in improving workers" perceived controllability of their jobs from a work stress reduction perspective.tive.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.6
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• pp.82-90
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• 2011

This paper proposes an advanced outdoor localization algorithm of a GPS(global positioning system)-INS(inertial navigation system) integration system. In order to reduce noise from the internal INS sensors, discrete wavelet transform and variable threshold method are utilized. The UPF (unscented particle filter) combines GPS information and INS signals to implement precise outdoor localization algorithm and to reduce noise caused by the acceleration, deceleration, and unexpected slips. The conventional de-noising method is mainly carried out using a low pass filter and a high pass filter which essentially result in signal distortions. This newly proposed system utilizes the vibration information of actuator according to fluctuations of the velocity to minimize signal distortions. The UPF also resolves non-linearities of the actuator and non-normal distributions of noises. Effectiveness of the proposed algorithm has been verified through the real experiments and the results are demonstrated.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.1
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• pp.41-52
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• 2014

The purposes of this study were to explore differences in utilization of information sources depending on the length of buyers' career and annual sales volume of stores where buyers work for. The questionnaire was prepared by the researcher and was answered by 200 buyers who purchase their items from Dondaemun market. The researcher analyzed the data using both ANOVA and Tukey's test as a post-hoc test. The conclusion of this study is summarized below. First, there were significant differences in utilization of information sources among buyer groups depending on the length of buyers' career. The buyers with more than 10 years career showed more effective utilization of information source such as resident buying offices, manufacturers, trade publications, trade associations, fashion reports, celebrities, window shopping, professional magazines, and advice from others. Second, there were significant differences in utilization of information sources among buyer groups depending on annual sales volume of the stores where the buyers work for. The buyer who work for the store with its annual sales volume in excess of 2 billion won showed more effective utilization of information source such as trade association, professional magazines, sales record, want slips, advertising results, sales trends, customer surveys, sales meetings, customer advisory panel, in-store merchandising bureau and advice from other experienced buyers. However, buyers of the store with its annual sales volume lower than 100 million won showed different pattern utilization of information sources such as vendors, trade publication, celebrities and advice from others.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.8
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• pp.28-34
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• 2020

In this study, hole-boss locking washers were developed to prevent vibrational loosening, and a benchmark test was conducted to compare these washers with existing wedge locking washers, which are imported and high-priced. The developed washers consist of an upper washer with bosses and a lower washer with holes, and the bosses are caught in the holes so that the bolt is not loosened. Additionally, the top side of the upper washer and the underside of the lower washer have small wedges perpendicular to the direction of the bolt loosening, suppressing slips. A test by the Korea Test Laboratory indicated that the ratio of the loosening torque to the joining torque is greater than 70%, confirming that the developed washers have a sufficiently high anti-loosening performance. A Junker test apparatus was manufactured for the testing of vibrational loosening and a test comparison between the proposed washers and the existing wedge locking washers shows that the proposed washers have a slower reduction in the clamping force and a higher loosening-resistance in a vibrational circumstance compared with the wedge locking washers. These results indicate that the developed washers demonstrate a high performance and boast price competitiveness.