• Proceedings of the Korea Concrete Institute Conference
• /
• 2002.10a
• /
• pp.431-436
• /
• 2002

In this paper, to seek a solution of reducing autogenous shrinkage three types of bar restricted concrete specimens which have similar compressive strength were tested. The three type of concrete were plain concrete-P25 type, $10^{\circ}C$ fly-ash replaced concrete-F10 type, and $1^{\circ}C$ expansion admixture replaced concrete-SP1 type, and with the test result an experimental study was conducted to gain the tensile stress of concrete. From the result of P25, SP1, F10 tests, it was found that by the age of 14 the ratios of tensile stress to tensile strength of three specimens are $75^{\circ}C$, $47^{\circ}C$, $52^{\circ}C$ respectively. so we came to a conclusion that the SP1-type concrete has better capacity to reduce autogenous shrinkage than F10-type concrete at similar compressive strength condition.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.32B no.10
• /
• pp.1347-1357
• /
• 1995

In this paper, we describe a modularized neuroclassifier for enhancing the recognition accuracy of mixed printed and handwritten numerals. This classifier combines four modularized subclassifiers using multi-layer perceptron module. The input of each subclassifier is comprised of a group of specialized feature sets. On applying this method to combining several subclassifiers for unconstrained handwritten numerals, the experimental result shows that the performance of individual subclassifier can be improved. In winner-take-all voting method, the result of subclassifier having the highest RF value is selected as the output. The generality of this classifier is tested with 1,080 printed and 3,000 handwritten numerals that was not shown in training the neural networks. Experimental results show 98.2% recognition rate. The typical recognition test with a threshold value(RF=1.5) has shown 97% recognition, 1% substitution and 2% rejection rates.

• Design & Manufacturing
• /
• v.9 no.1
• /
• pp.27-30
• /
• 2015

The injection molding is used in more than 70% of total production of plastic products. Weld line in injection molded part is one of the defects in injection molding process. Weld line deteriorates not only appearance quality but also mechanical property. In this study, tensile strength about material such as ABS, PP, PA and PS was tested. as the results, the first result appears that weld's strength retention ratio's are 0.90, 0.84, 0.85, 0.76 and the second result apeears that weld depth decrease as processing temperature increased.

• Proceedings of the KSME Conference
• /
• 2001.06d
• /
• pp.1014-1019
• /
• 2001

A numerical investigation was performed to determine the effect of airfoil on the optimum flap height using NACA 00XX and 44XX airfoils. The six flaps which have 0.5% chord height difference were selected. A Navier-Stokes code, FLUENT, was used to calculate the flow field of the airfoil. The code was first tested as a benchmark by modelling flow around a NACA 4412 airfoil. Predictions of local pressure coefficients are found to be in good agreement with the result of the experimental result. For every NACA 00XX and 44XX airfoil, flap heights ranging from 0.0% to 2.5% chord were changed by 0.5% chord interval and their effects were also studied. Representative results from each case are presented graphically and discussed. It is concluded that this initial approach gives an idea for the future development of the wind turbine optimum design.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.17 no.9
• /
• pp.2373-2380
• /
• 1993

This paper addresses the design procedure and testing result of a servo driven pan/tilt device which is capable of tracking arbitrary movement of a specified target object. In order to achieve real-time acquisition of feedback signal, a 2 degree-of freedom non-contact type displacement follower has been employed in stead of vision camera. The performance of the designed system is tested for different target velocities and control gains. The test result shows the satisfactory performance to be adopted as an effective tool for visual transfer in the context of teleoperation.

• Journal of Korean Academy of Nursing
• /
• v.33 no.3
• /
• pp.376-385
• /
• 2003

Purpose: This study was conducted to develop gerontological curriculum model which reflects the need of Korean society. Method: Three round Delphi survey method was applied to find consensus of gerontological nursing competencies (knowledge, attitudes and skills) for graduates of nursing schools from the panel of gerontological nursing practice experts. Important concepts in gerontological nursing were delineated from literature review and discussions of gerontological nursing educators. Based on these results the gerontological nursing curriculum model was developed and course structure outlined by the researchers as a group. Result: As the result of delphi survey, 32 items of knowledge, 29 items of attitude, and 21 items of skill were identified. The curriculum model constructed around a cube with three plane- functional capacity levels, settings, and nursing practice. Specific knowledge, attitudes and skills for gerontological theory and practicum course were suggested. Competency items were assigned to theory and/or practice. Conclusion: A curriculum model for gerontological nursing has been developed by a group of gerontological nursing educators. The curriculum model should be further tested and developed with detailed theory and practicum course outline and textbooks.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.05a
• /
• pp.443-448
• /
• 2001

This paper presents a bond characteristics of high strength steel reinforced concrete members. High strength steel is what yield strength is higher than that of normal strength steel. So, the amount of flexural steel needed in R.C. members can be decreased. In result, it is expected that the workability and structure quality can improve and man power can minimize. For this purpose, specimens were made and tested with experimental parameters, such as concrete strength, steel diameter and yield strength. The result showed that under same tensile force of steel, in case of substituting normal strength steel with high strength steel, maximum bond stress increased and development length didn't almost change. In addition, the governing equation of bond and bond stress verse slip relationship were derived and compared with test values such as maximum bond stress, slip and bond stiffness.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.05a
• /
• pp.269-274
• /
• 2001

The purpose of this study is to evaluate basic properties of artificial aggregate using concrete sludge according to mixing ratio. Cement, waste phosphogypsum and Powder of blast furnace slag are used with binder of artificial aggregate. Specific gravity, absorption are tested for basic property, and impacting, abrasion and crushing tests are done for characteristics of strength on the aggregate, including comparison with crushed stone. Bry specific gravity was ranged about 1.16 to 1.30 the test result of the aggregates and shape is round In the result of tests, it is concluded that qualities of the aggregates using concrete sludge are slightly lower than crushed stone but it is similiar with sintering artificial lightweight aggregate in high temperature.

• Journal of the Korean Society for Library and Information Science
• /
• v.9
• /
• pp.99-118
• /
• 1982

This paper first reviews various techniques proposed for automatic indexing with special emphasis placed on statistical techniques. Frequency-based statistical techniques are categorized into the following three approaches for further investigation on the basis of index term selection criteria: term frequency approach, document frequency approach, and probabilistic approach. In the experimental part of this study, Pao's technique based on the Goffman's transition region formula and Harter's 2-Poisson distribution model with a measure of the potential effectiveness of index term were tested. Experimental document collection consists of 30 agriculture-related documents written in Korean. Pao's technique did not yield good result presumably due to the difference in word usage between Korean and English. However, Harter's model holds some promise for Korean document indexing because the evaluation result from this experiment was similar to that of the Harter's.

• Korean Journal of Veterinary Research
• /
• v.47 no.3
• /
• pp.281-283
• /
• 2007

This study was conducted to survey of Ehrlichia (E.) canis and Borrelia (B.) burgdorferi antibodies among clinically healthy German shepherd dogs (116 females and 120 males) using a ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA) in Korea. Whole blood samples are collected from the 236 dogs and are tested to detect E. canis and B. burgdorferi antibodies by using ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA). Confidence interval comparisions revealed that dogs of 4-6 years have higher prevalence with a seropositive result (CI=0.17-0.45) in E. canis than the other age groups but there are no differences among age groups in B. burgdorferi. Also, no differences with a seropositive result were found among different regions in E. canis and B. burgdorferi antibodies. In conclusion, this study was the first large scale survey of canine E. canis and B. burgdorferi antibodies in Korea and provide an useful reference for clinicians.