• Title/Summary/Keyword: Test&Evaluation

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Trend Analysis of Secondary School Chemistry Teacher Certification Examination: School Years 2009~2013 (2009~2013학년도 중등교사 임용시험 화학교과 내용학 문항의 출제 경향 분석)

  • Choi, Byungok;Kim, Yongseong
    • Journal of The Korean Association For Science Education
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    • v.33 no.6
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    • pp.1202-1218
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    • 2013
  • This study analyzed questions related to the content knowledge on the subject of chemistry for middle and high school teacher employment examinations conducted from the school years 2009 to 2013 based on the evaluation scope of the chemistry subject content knowledge and evaluation contents that were presented by the Korea Institute for Curriculum and Evaluation (KICE). To achieve the objectives of this study, a total of 140 questions were collected with respect to the questions that appeared on the test over the last 5 years, which aimed to evaluate the level of applicants' knowledge related to the contents of chemistry subject. The ratio of the contents covered in the test was assessed based on the scope of evaluation and the items for evaluation among the 4 subjects. Based on the results, suggestions were presented in relation to the operation of the chemistry curriculum for the Department of Chemistry Education at the college of education or the restructuring of the evaluation scope. There was a significant difference in the ratio of items that appeared on the test among the 4 subjects related to the content knowledge on chemistry. Also, there was a remarkable difference in the ratio of items covered in the test among the evaluation scope by subject. The results of the analysis on the evaluation content items suggested that 41 items out of 122 did not appear in the teacher employment examination for 5 years. Based on such results of analysis, this study discussed the need for readjusting the ratio of items covered in the test on content knowledge related to chemistry or the evaluation scope and evaluation content items.

Hydrodynamic evaluation for developing the inflatable kayak (인플래터블 카약 개발을 위한 유체역학적 성능평가)

  • Hah, Chong-Ku;Lim, Lee-Young;Ki, Jae-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.6
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    • pp.623-630
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    • 2013
  • This study was to evaluate hydrodynamic performance evaluation between an abroad product, a developed inflatable kayak and new developed kayaks. In order to test, inclining and turning trial test were carried out in the Ocean engineering Basin. Also, resistance test was carried out using a reduced scale model in the circulating water channel. In conclusion, stability of KONA was evaluated was the most greatest, the coefficient of resistance and center of gravity from RD-FK-12 were considerable, and turning performance of RD-FK-11 was greater than this of KONA and RD-FK-12.

Evaluation of Long Duration Current Impulse Withstand Characteristics of ZnO Blocks for High Voltage Surge Arresters (초고압 피뢰기용 ZnO 소자의 장시간 방전내량 특성 평가)

  • Cho, Han-Goo;Yun, Han-Soo;Kim, Seok-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.4
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    • pp.398-403
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    • 2006
  • This paper describes the evaluation of the long duration current impulse withstand characteristics of ZnO blocks for high voltage surge arresters. Four ZnO varistors were manufactured with the general ceramic production method and the long duration current impulse withstand test, electrical uniformity evaluation test and microstructure observation were performed. All varistors exhibited high density, which was in the range of $5.42{\sim}5.46g/cm^3$. In the electrical properties, the reference voltage of samples was in the range of $5.11{\sim}5.25\;kV$ and the residual voltage was in the range of $8.314{\sim}8.523\;kV$. In the long duration current impulse withstand test, sample No.2 and No.3 failed at the 2nd and 4th shot of series impulse currents, respectively, but the rest survived 18 shots during the test. Before and after this test, the variation ratio of the residual voltage of samples survived was below 0.5 %, which was in the acceptance range of 5 %. According to the results of the test, it is thought that if the soldering method is improved, ZnO varistors would be possible to apply to the high voltage arresters like the station class and transmission line arresters in the near future.

Development and Enforcement of Short Case Test Items for Evaluation in Undergraduate Course of Plastic Surgery: 3 Years Experience (학부 성형외과학 과목평가를 위한 짧은 사례문항의 개발과 시행: 3년간의 경험)

  • Hwang, Kun;Park, Jun Ho;Lee, Se Il
    • Archives of Plastic Surgery
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    • v.33 no.2
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    • pp.225-232
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    • 2006
  • The aim of this study is to evaluate the clinical competence of medical student using short case test items. Development of short case test items with definition of an assessment of subject, choice of clinical stations sampling, identification of components of clinical competence to be evaluated, and assessment of practicability and results exploitation. For the last three years 28, 48 and 30 topics were developed annually. Among them 20, 23 and 23 topics were selected. About 50 students were examined annually. The mean score was 72.7, 57.1, 64.3 respectively. The mean preparation time of the students for the examination was 9.8 hours. About 60% of the students prepared the test in small group activity. Our experience suggests that short case test items be feasible for evaluation of student learning in Plastic Surgery. This method should be considered as a useful tool to assess medical student's competence or even an examination for board certification.

Development of Ceramic Roll Materials for Food Grinding Processing and Evaluation of Mechanical Behavior (식품분쇄용 세라믹 롤 재료 개발과 기계적 특성평가)

  • 강위수
    • Journal of Biosystems Engineering
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    • v.26 no.1
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    • pp.47-56
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    • 2001
  • In order to prevent the possibility of mixing of metal powder during food grinding processing with the metal roll mill this study was conducted to develope the materials of ceramics roll as a substitute of gray cast iron mill. Since the ceramics is brittle material and can be broken easily by a crack, it was needed to develope engineering ceramics roll materials with high elastic modulus and fracture toughness. Adding 0∼50 wt% Al$_2$O$_3$as densification additives to porcelain body material and forming the ceramics an different condition, mechanical properties were evaluated. The material structure’s densification process was analyzed by SEM and XRD. The evaluation of the mechanical properties of ceramics roll materials were compared and analyzed by non-destructive test using Young’s modulus and destructive test using 3-point bending strength and fracture toughness. The results showed several correlative results. Porcelain body material with 40 wt% Al$_2$O$_3$content heated at 1,200$\^{C}$ for 5h was high bulk density of 2.77, Young’s modulus of 118.4Gpa, 3-point bending strength of 137 MPa and fracture toughness of 2.88 MPa$.$m$\^$$\sfrac{1}{2}$/ . After analyzing the relationship between non-destructive test and destructive test, the coefficient of determination was more than 0.9. Therefore, the evaluation of non-destructive test by ultrasonic was turned out to be feasible in evaluating the mechanical properties of ceramics.

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Properties Evaluation on Aluminum for Die-casting(ADC 12) to Packing Case of Composite Sensor (복합센서 케이스용 알루미늄 다이캐스팅(ADC 12) 합금의 특성평가)

  • Son, Jae-Hwan;Oh, Sang-Kyun;Kim, Dong-Bae;Han, Chang-Woo
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.2
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    • pp.141-145
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    • 2006
  • In case of sense case manufactured by method of outage capacity, sensitivity is declined by outside effect and method of the photo electricity has a problem in transmission. therefore, packing case of composite sense should be developed to improve such a problem about influence of outside environment and its property evaluation has been performed. Mechanical property and result of analysis & test evaluation of Mat'l on aluminum die-casting(ADC 12type) Mat'l developed are as following. Tensile test piece, No. 4 of KS B 0801, has been applied to mechanical property test of Mat'l and It has been tested by method of metal mat'l tensile test(KS B 0802 : 2003). It can be found that physical property to KS(Korea Standard) is excellent. and homogeneous mechanical property appears. Test of Mat'l analysis has been performed by using OE Spectrometer, according to ASTM E 1251 : 1994 regulation. Consequently, good and homogeneous component contents classified by element to standard, except for Fe, have been obtained with coordination of Fe content as below 1.3% from composition standard of Aluminum Die-casting.

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Application of WCT(Wet Compaction Test) for Fiber Evaluation

  • Seo, Yung-B.;Ha, In-Ho;Lee, Chun-Han
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.5 s.118
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    • pp.9-15
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    • 2006
  • Wet compaction test (WCT) is a fiber evaluation method where wet fibers are compressed at one side of a cylinder and water drains out from the other side. The consistency of the fiber furnishes and their pressures are recorded during the test. In the previous study we found that WCT results always gave better coefficients of determination in fiber furnish drainage, and paper properties (density, tensile, tear, and burst strength) than those of WRV (water retention value). Fiber freeness and fiber length correlated well with drainage and tear strength of the furnishes, respectively; however, their correlations were very much improved by combining the WCT results. In this study, we used the WCT test for fractionated fiber furnishes to see whether improvement of the WCT is possible. We found that strength properties such as breaking length and burst index were correlated better with the fractionated long fiber furnishes. Drainage was greatly affected by the presence of short fiber furnishes. We used bleached chemical pulps (SwBKP, HwBKP), recycled pulp (OCC), and mechanical pulp (BCTMP) as fiber furnishes in this study. Fiber fractionation can be performed on-line in these days by using multifractor and WCT can be used as an on-line test in papermachine in the future.

Limitations and improvement of the in situ measurements of ground thermal conductivity in Korea (국내 지중열전도도 측정 방법의 한계 및 개선 방향)

  • Shim, Byoung Ohan
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.195.2-195.2
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    • 2011
  • The borehole heat exchanger of Geothermal Heat Pump (GHP) system should be sustainable and cost effective for long term operation. To guaranty the performance of the system thermal Response Tests (TRTs) with simple recommended procedures have been applied in many countries. Korea government developed a standard TRT procedure in order to control the quality on GHP projects. In the TRT procedure interpretation method has a rule that data set has to be interpreted by the line source model(LSM). The LSM employes some assumptions that surrounding medium is homogeneous and the line source is infinite and constant heat flux, however real ground condition is unisotropic and heterogeneous, and showing regional or local ground water flows in many cases. We need to develope improved evaluation models to estimate accurate ground thermal conductivity with respect to geological and influence of ground water because current TRT standard test procedure has limitations to be applied for every locations and system. This study surveyed the uncertainty of the thermal parameters from the interpretation method considering different evaluation period. The interpretation of 208 TRT data sets represents limitations of LSM application that some obtained ground thermal conductivities are statistically unstable and convergence time of ground thermal conductivity over test period shows trends responding the length of test period. This evaluation study will be helpful to provide some effective procedure for the thermal parameter estimation and to complement current TRT standard procedure.

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Fatigue Life Evaluation for Railway Turnout Crossing using the Field Test (현장측정을 통한 분기기 망간 크로싱의 피로수명 평가)

  • Um, Ju-Hwan;Choi, Jung-Youl;Park, Yong-Gul
    • Journal of the Korean Society for Railway
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    • v.9 no.2 s.33
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    • pp.169-173
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    • 2006
  • The major objective of this study is to investigate the fatigue life evaluation of immovability crossing for railway turnout by the field test. In railway engineering, an appliance is necessary to allow a vehicle to move from one track to another. This appliance came to be known technically as turnout. So, turnout is required very complex railway technologies such as rolling stock, track. Due to the plan under the application of high speed train, turnout are needed more stable far fatigue behaviors. It analyzed the mechanical behaviors of turnout crossing with propose its advanced technical type on the field test and fatigue evaluation far the dynamic fatigue characteristics. As a result, the advanced type crossing are obviously effective for the fatigue damage ratio and dynamic response which is non-modified type. The analytical and experimental study are carried out to investigate the passing path of contact surface and fatigue damage trend decrease dynamic stresses and deflections on advanced crossing type, And the advanced type reduce dynamic fatigue damage ratio and increase fatigue life(about each 38%) more than non-modified type. From the field test results of the servicing turnout crossing, it is evaluated that the modification of contact angle, weight, material and sectional properties is very effective fur ensure against fatigue risks.