• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.2
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• pp.79-84
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• 2012

This study consist of two parts. One is development of a self-propelling vinyl remover which was already reported at the previous paper. This is the second part of the study. For the study, an attached vinyl remover was developed. It was consisted of connecting tractor to bucket, removing bucket from tractor, and the process was the tractor's assistance hydraulics. In the case of an attached vinyl remover, the vinyl was twisted 0.5times per 30~85cm length. The bobbin's diameter was 190mm and it's stable travelling speed was 1m/s. The revolution of the remover wheel was 90rpm to maintain the wheel's linear velocity. As seen at performance test at the field which had 950mm ridge intervals and 10 a area, the average working speed was 1m/s and the turning time was 20seconds. Therefore, the working performance was 24.5min/10a. The efficiency of used vinyl remover was 97% and working conditions were good.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.2
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• pp.50-59
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• 2010

In this paper, two kind of free-form progressive addition lenses (PALs) were designed with Zernike polynomial surface and anatomically accurate finite presbyopic schematic eyes which have aspheric cornea, aspheric GRIN crystalline lens, aspheric retina, and Gaussian apodization factor. Geometrical and diffraction MTFs were used for the optimization process in sequence. 5th orders of Zernike polynomials were used for the evaluation of progression zones of the two examples. The target MTF was set as 0.22 at 100 lp/mm which satisfies the standard visual resolution. These examples were fabricated with a CNC diamond turning machine controlled by slow tool servo (STS). After polishing process, the wavefront aberrations were measured with a laser interferometer on the ten test points across the progression zones and then compared with three current commercially available PALs on the optical performance. Astigmatic aberrations of the examples are very lower than the three selected PALs and have more increased stabilized progressive intermediate zones and near zones. It is expected to give better clear and comfortable distance, intermediate and near visions than other conventional PALs and to improve the adaptability of presbyopic patients to PALs.

• Korean Journal of Human Ecology
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• v.12 no.2
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• pp.253-263
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• 2003

The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.6 s.144
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• pp.551-558
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• 2005

In this paper, horizontal manoeuvrability of an underwater vehicle near free surface was investigated. Planar Motion Mechanism(PMM) tests were performed at the shallow depth within 4.5 times of vehicle's diameter. Hydrodynamic coefficients related to the horizontal movement were estimated from the measured data using Least SQuare(LS) method and analyzed at each submerged depth. Furthermore, horizontal dynamic stability, trajectory of turning and zigzag test were investigated for the various depths. As underwater vehicle is positioned nearer to the free surface, forces increase and moment decreases. Tested model was found to be stable only at the depth 0.5 times of vehicle's diameter.

• Journal of the Korean Home Economics Association
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• v.34 no.2
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• pp.183-199
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• 1996

The objective of this study was to provide fundamental data on somatotype for elderly women by classifying the somatotype and analysing the 3 characteristics of their somatotype. The subject were 368 women of 60~84 years old, they were analyzed indirect photography. To find out differences among the age groups, the 368 subjects were grouped into two age groups (Group 1 ; age 60 to 69, Group 2 ; aged 70 to 84). Data were analyzed using Factor analysis, Cluster analysis, duncan test and Analysis of variance. Through the factor analysis, 27 items from photometric measurements respectively. Cluster analysis was applied for classification of somatotype. The results of this study were as follows. 1. The characteristics of Elderly women's somatotype were bending of the upper-torso, fatness of the waist and abdomen, drooping of the bust and shoulder and hip. In addition, height, girth, depth and width items were decreased in their sizes respectively. 2. The characteristics of clusters were as follows. Type 1 was straight somatotype in which the plumb line through tragion, the bust depth and under bust depth region laterally. Type 2 was swayback somatotype in which the upper portion of protruding point on the back was bent forward but the lower portion of protruding point had a characteristics of turning over somatotype. Type 3 was bending somatotype. Namely, this type was shorter than average and below the average fatness. Generally, the lateral view silhouette of elderly women was the straight type and changed into bending type as the age increases.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.273-276
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• 2011

Voice over Internet Protocol(VoIP) compared to the traditional PSTN communications costs and because of the ease of use has been widespread use of VoIP. Broadband Convergence Network (BCN) as part of building with private Internet service provider since 2010, all government agencies are turning to the telephone network and VoIP. In this paper, we used the Internet on your phone in the IETF SIP-based IP-PBX is a hacking attack analysis studies. VoIP systems are built the same way as a test bed for IP-PBX hacking attacks and vulnerabilities by analyzing the results yielded. Proposes measures to improve security vulnerabilities to secure VoIP.

• Journal of the Korean Professional Engineers Association
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• v.33 no.3
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• pp.71-79
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• 2000

The effects of alkali salts adding on the cooking quality improving in dried noodles were investigated in the good texture maintaining for preventing solid soluble losses ,through chemical analysis and actual manufacturing practice ,the following results were obtained. Experiments were took a special flour of ASW:DNS=70:30, thickening agent(TA) composed of K2CO3 58%, Na2CO3 36% and Na4P2076%, and emulsified oil(EO) mixing of corn oil 44%, polysorbate 23%, emulsifier(ester of glycerin and fatty acids) 21%, soy lecithin 12%. When the mixing ratio of TA and EO to flour, is 0.03 and 1.5%(w/w) or morel than, satisfied the good quality. The water soluble solid matters content of the lowest 3.2% in the treating group that TA and EO is 0.03 and 1.5%(w/w) respectively, comparing to the 7.3% in the control group provides a excellent cooking quality. The research achieves the similar effects at specific gravity, water absorption ratio, weight increasing rate and volume expansion ratio. According to appearance test the more treating of TA turn the noodle into deeper yellow-green color. Turning to the deeper yellow color according to the increasing of EO provides better

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.71-77
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• 2007

Dangerous driving is a major cause of traffic accidents in Korea. It becomes more serious for commercial vehicles due to higher fatality rates. The Safe Driving Management System (SDMS), developed in this research, is a comprehensive solution that monitors and stores driving conditions of vehicles, detects dangerous driving situations, and analyzes the results in real time. The Safe Driving Management System consists of a vehicle movement information controller, a dangerous driving detection algorithm and a vehicle movement data report and analysis program. The dangerous driving detection algorithm detects and classifies dangerous driving conditions into representative cases such as sudden acceleration, sudden braking, sudden lane change, and sudden turning. Both computer simulation and vehicle test have been conducted to develop and verify the algorithm. The Safe Driving Management System has been implemented on commercial buses to verify its reliability and objectivity. It is expected that the system can contribute to prevention of traffic accidents, systemization of safe driving management and reduction of commercial vehicle operation costs.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.237-242
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• 2019

This research was conducted for the normal adults and kids to know the abdominal muscle activities by stimulating Vojta's brust zone. It was conducted for 10 adults who were average 21.5 years old and 10 kids who were 12.1 years old and did it once. We used EMG to know the abdorminal muscle activities and we chose the research method 'independent t test'. Only two adults and kids among subjects have reactions and the others have no reactions. This research reveals that hypothesis, Vojta's brust zone stimulates abdominal activities, didn't coincide completely but we will have more exact results by researching other subjects and choosing proficient method several months, not once.

• Computers and Concrete
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• v.18 no.2
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• pp.267-278
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• 2016

In order to observe the internal damage of concrete in real time, we introduced acoustic emission nondestructive detecting technology into a series of fracture tests; the test results revealed the whole process that concrete undergoes when it sustains damage that leads to failure, according to the change rules of the acoustic emission parameters. The results showed that both the initiation and unstable loads can be accurately determined using the abrupt change of the acoustic emission rate curves and the turning point of the acoustic emission parameters' accumulative curves. The whole process, from damage to failure, includes five phases, beginning with damage, such as cracking, a stable crack growth process, a critical unstable stage, and unstable propagation. The brittle fracture characteristics of concrete change when steel bars are joined, because the steel bars and the concrete structure bond, which causes an increase in the acoustic emission signals within the fracture process of the reinforced concrete. The unstable propagation stage is also extended. Our research results provide a valid methodology and technical explanations, which can help researchers to monitor the cracking process of concrete structures, in real time, during actual projects.