• Journal of the Korean Society of Industry Convergence
• /
• v.14 no.2
• /
• pp.79-85
• /
• 2011

This study has been experimented about refrigeration capacity difference. It has been used 3 method, Manual expansion valve, thermostatic expansion valve and capillary expansion valve, and tested under the same condition by using the performance testing of parallel expansion. In temperature change of the temperature room, thermostatic expansion valve method displayed the most lower temperature, $-18^{\circ}C$. In addition, the temperature, just before the expansion, also displayed the best result which was $4^{\circ}C$ lower than other expansion valve. In these results, it can be used for performance testing of parallel expansion refrigeration system.

• The Journal of Information Technology and Database
• /
• v.8 no.1
• /
• pp.95-104
• /
• 2001

In the text classification domain, labeling the training documents is an expensive process because it requires human expertise and is a tedious, time-consuming task. Therefore, it is important to reduce the manual labeling of training documents while improving the text classifier. Selective sampling, a form of active learning, reduces the number of training documents that needs to be labeled by examining the unlabeled documents and selecting the most informative ones for manual labeling. We apply this methodology to Naive Bayes, a text classifier renowned as a successful method in text classification. One of the most important issues in selective sampling is to determine the criterion when selecting the training documents from the large pool of unlabeled documents. In this paper, we propose two measures that would determine this criterion : the Mean Absolute Deviation (MAD) and the entropy measure. The experimental results, using Renters 21578 corpus, show that this proposed learning method improves Naive Bayes text classifier more than the existing ones.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.10
• /
• pp.888-893
• /
• 2000

This paper deals with the development of an automatic design software for DC servo motor control, which provides good performance with rapid response and velocity control accuracy. In the proposed method, the design is automatically executed using Matlab, and iterative learning control algorithms are used in the design process. We applied this method to 50W, 100W, 200W, 300W, 500W, 750W, 1.8kW and 4.5kW DC servo motors which are widely used in the industry. We compare the results of the manual tuning design method with that of the automatic design method presented in this paper. From the experimental results, we can find that the performance of the proposed method is better than that of the manual tuning design method.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.5
• /
• pp.203-211
• /
• 1996

This paper describes CAD tools for the construction of image database in IC chip analysis CAD system. For IC chip analysis by high-resolution microscopy, the image database is essential to manage more than several thousand images. But manual database construction is error-prone and time-consuming. In order to solve this problem, we develop a set of CAD toos that include image grabber to capture chip images, image editor to make the whole chip image database from the grabbed images, and image divider to reconstruct the database that consists of evenly overlapped images for efficient region search. we also develop an interactive pattern matching method for user-friendly image editing, and a heuristic region search method for fast image division. The tools are developed with a high-performance graphic hardware with JPEG image comparession chip to process the huge color image data. The tools are under the field test and experimental resutls show that the database construction time can be redcued in 1/3 compared to manual database construction.

• Journal of the Ergonomics Society of Korea
• /
• v.23 no.4
• /
• pp.1-8
• /
• 2004

The objective of this study is to identify the effects of material position and physical fatigue on postural stability. Ten male subjects participated in this study. After bicycling exercises, their centers of pressure (COPs) were measured under four material handling positions and four excercise levels. The measured COPs were then utilized to calculate postural sway length in each experimental condition. Subjects' postural stability was quantified using the sway length. Results showed that the effect of different material handling position was significant on the postural sway length in both the posterior-anterior axis and the medio-lateral axis. Results also showed that the postural sway length was increased as physical fatigue accumulated, significantly in subject's posterior-anterior axis. The results imply that bearing a material on the back or front with both hands appeared to cause least sway length and instability.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.12 no.2
• /
• pp.1-10
• /
• 2006

The purpose are to assess the efficacy of a contact lateral-wedged insole with strapping on the femorotibial angle in patients with varus deformity osteoarthritis of the knee after treatment period. 25 outpatients with knee osteoarthritis (OA) were randomized to be treated with a contact lateral-wedge insole with strapping. Standing radiographs were used to analyze the femorotibial angle for each subject. The result of repeated two-way ANOVA's reveled that a contact lateral-wedged insole with strapping produced significantly differences in the femorotibial angle between groups after treatment period (P<0.05). and repeated one-way ANOVA's reveled that it produced significantly differences in the femorotibial angle between experimental groups after treatment period (P<0.05). We suggest that these results may be beneficial for manufacturing foot orthotic devices, such as wedged insoles, to control medial and later compartment forces in the knee varus-valgus deformity.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.3 no.2
• /
• pp.30-41
• /
• 1995

Gear rattle is a source of vibration and noise in automotive gearbox casing and generally occurs at or near system resonant frequencies. The neutral gear rattle of the gearbox. is affected by the stiffness and hysteresis torque in the clutch disk and drag torque determining balancing point of the clutch disk operating range. The experiment is carried out in the pre-damper type clutch and a manual transmission of a automobile equipped for inline four-sylinder four-cycle 1.5L MPI engine and the computer simulation is executed by 5th order Runge-Kutta method. The results of the simulation analysis and experimental studies show the dynamic behavior of clutch and a phenomenon of the neutral gear rattle with respect to drag torque and torsional characteristics of the clutch.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.9 no.2
• /
• pp.59-67
• /
• 2003

The purpose of this study was to identify the effects of eccentric exercise of affected hip abductor muscles on Gait balance in patient with hemiplegia. 30 patients with hemiplegia were recruited among in and out patients of Gil Hospital(age x=50.5, SD=10.1, range 37-80. post stroke days x=383.2, SD=309.3, range 57-1165). These patients were divided into eccentric and control groups by random sampling. TUG were used for this study. Paired t- test was used to identify the effects of eccentric exercise of hip. The results were stastically significantly differences in the effect of exercise between experimental and control groups by TUG(p<0.05). The results indicate that the eccentric exercise of affected hip abductor muscles is effects on gait balance in patient with hemiplegia.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.15 no.2
• /
• pp.35-43
• /
• 2009

Purpose : The purpose of this study was to measure the change of strength of trunk flexion and extension on abdominal and back muscles. Methods : Each taping group 1(n=14), taping group 2(n=14), taping group 3(n=14) and control group(n=15) were measured a muscle strength by Biodex at first test, second test, third test and forth test in 3 days. Results : The strength of trunk flexion and extension was significantly different among the experimental groups (p<.05). It also shows that significant increasing of muscle strength at 48 hours after application of taping (p<.05). Conclusion : In conclusion, we were found that taping technique base on taping type show immediately assistance of muscle strength and enduring effect for 48 hours.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.5
• /
• pp.399-405
• /
• 2013

This study demonstrates the utilization of light microscopy and Fast Fourier Transform-Peak Finding (FPF) method for microfibril angle (MFA) measurement from unstained sections of red pine (Pinus densiflora). To obtain an image with optimal contrast and resolution for MFA measurement, effects of numerical aperture (NA) of condenser lens and color filters were investigated. About 60% of NA of the maximum condenser NA produced an image with optimal contrast, but a color filter with short wavelength range (DAPI) created images with improved resolution. Manual angle measurement and the FPF method were applied to the image with optimal contrast for MFA measurement. The experimental results from the FPF method were considered to be more repeatable and less subjective than those from the manual angle measurement.