• Proceedings of the KSR Conference
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• 2007.11a
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• pp.801-808
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• 2007

Rotem Company has designed and manufactured bogie for Diesel Multiple Unit (DMU) according to the European standard UIC615-4, which si normally used for designing bogie frame. Because the countries located in Middle East do not have their own regulations for bogie design, most of running bogies in Middle East are designed by using European standard UIC615-4. UIC615-4 specifies the loads that bogie frame should withstand, indicates the way of material data to be used and the principles to be during verification by analysis and test. The bogie frame depends on the load conditions and magnitudes which are subjected to during service and characteristics of materials they are manufactured from. From the above reason, Rotem Company has performed Finite Element Analysis and load tests on the bogie frame according to UIC615-4. This research contains the results obtained by the analysis and the load tests. Also, this research verifies that the bogie frame has a static strength and fatigue strength. The analysis is carried out using I-DEAS 12 NX Series and specially designed test jigs and equipment are used for the load tests.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.1
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• pp.57-65
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• 2002

Pneumatic cylinder is widely used fur mechanical handling systems. Often, the impact occurs at the both ends points of pneumatic cylinder and generates the destructive shock with in the structural operating members of the machine or equipment. To reduce the damage of system, therefore, shock absorbing devices are required. Cushioning of pneumatic cylinders at one or both ends of piston stroke is used to reduce the shock and vibration. The cylinder body have to withstand under conditions of high velocity and load. In this research pneumatic cushioning cylinder moving tests have been conducted for different load mass and supply pressure. The velocity of pneumatic cylinder actuation system which is set vertically with multiple orifice cushion sleeve is controled with the meter-in/out control system. This study examines the dynamic characteristics of pneumatic cylinder which are used as cushion devices. It turns out that the cushion pressure is mainly a function of the external load rather than the supply pressure. The cushion region characteristics was also revealed in the meter-in control system.

• International Journal of Concrete Structures and Materials
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• v.18 no.3E
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• pp.151-159
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• 2006

A total of 32 pullout tests were performed for the multiple headed bars relatively deeply embedded in reinforced concrete column-like members. The objective was to determine the minimum embedment depth that was necessary to safely design exterior beam-column joints using headed bars. The variables for the experiment were embedment depth of headed bar, center-to-center distance between adjacent heads, and amount of supplementary reinforcement. Regular strength concrete and grade SD420 reinforcing steel were used. The results of the test the indicated that a headed bar embedment depth of $10d_b$ was not sufficient to have relatively closely installed headed bars develop the pullout strength corresponding to the yield strength. All the experimental variables, influenced the pullout strength. The pullout strength increased with increasing embedment depth and head-to-head distance. It also increased with increasing amount of supplementary reinforcement. For a group of closely-spaced headed bars installed in a beam-column joint, it is recommended to use column ties at least 0.6% by volume, 1% or greater amount of column main bars, and an embedment depth of $13d_b$ or greater simultaneously, to guarantee the pullout strength of individual headed bars over 125% of $f_y$ and ductile load-displacement behavior.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.769-773
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• 2013

Background: A literature review on 1,104,269 cancer patients concluded that the prevalence of multiple primary malignancies (MPM) is between 0.73% and 11.7%. MPMs seem to have higher incidence than that influenced by hazard only. The purpose of this study was to investigate clinically useful information for effective screening for synchronous and metachronous second primary cancers and to identify a potential surveillance protocol. Materials and Methods: Using statistical and epidemiological indicators we evaluated the patients with MPMs (double locations) admitted to Dr. Abdurrahman Yurtarslan Ankara Oncology Education and Research Hospital between 1981 and 2010. Results: Out of the 130 cases, 24 (18.4%) were synchronous while 106 cases (81.6%) were metachronous tumours. Mean interval time from first to second primary cancers was 4.65 years (0-27 years). The most frequent malignant associations were breast-breast, breast-endometrium and breast-ovary. Both primary and secondary tumors tended to be in an advanced stage explained by the low compliance of the patients to follow-up. Conclusions: The possibility that MPMs exist must always be considered during pretreatment evaluation. Screening procedures are especially useful for the early detection of associated tumors, whereas careful monitoring of patients treated for primary cancer and a good communication between patients and medical care teams should ensure early detection of secondary tumors, and subsequent appropriate management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.45-50
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• 2012

This paper on analysis of roundness error after boring turning of Al-6061 materials with CNC lathe. Experiment applying turning parameters is based on experimental design method. A design and analysis of experiments is conducted to study the effects of these parameters on the roundness error using the S/N ratio and analysis of ANOVA. Multiple linear regression analysis is applied to compare experimental with predicted data in consideration of roundness error. To fixation pressure and the opening which are a turning parameter, the cutting depth and feed speed respected the objective attainment of dissertation and to be applied the result they investigated.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.4
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• pp.447-458
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• 2013

The present operating system for the atmospheric monitoring network in the city of Seoul, Korea, has been established since the late 90s by the Korean Ministry of Environment (KMOE). In this research, it was evaluated by the multi-statistical approaches through combinations of time series analysis, correlation matrix, and multiple cluster analysis. Finally, road traffic including resuspended materials can be one of the main sources of particulate matter in the atmosphere. Based on its importance, it will be significant challenges in quantitative evaluation of its contribution to airborne concentrations. The future directions for their amendments such as a new management plan for the source of road dust (including car emissions) were devised and proposed based on the statistical judgements derived in this research.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.4 s.193
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• pp.93-101
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• 2007

Aluminum alloy which is one of the light materials has been tried to apply to light weight vehicle body. In order to do that, welding technology is very important. In case of the aluminum laser welding, the strength of welded part is reduced due to porosity, underfill, and magnesium loss. To overcome these problems, laser welding of aluminum with filler wire was suggested. In this study, experiment about laser welding of AA5182 aluminum alloy with AA5356 filler wire was performed according to process parameters such as laser power, welding speed and wire feed rate. The tensile strength was measured to find the weldability of laser welding with filler wire. The models to estimate tensile strength were suggested using three regression models and one neural network model. For regression models, one was the multiple linear regression model, another was the second order polynomial regression model, and the other was the multiple nonlinear regression model. Neural network model with 2 hidden layers which had 5 and 3 nodes respectively was investigated to find the most suitable model for the system. Estimation performance was evaluated for each model using the average error rate. Among the three regression models, the second order polynomial regression model had the best estimation performance. For all models, neural network model has the best estimation performance.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.383-392
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• 2014

Purpose: In this study, we sought to understand the risk factor for chronic disease of workers by studying the association between occupational standing time and metabolic syndrome(MetS) in full-time 300 male workers. Materials: Data on age, life habit, work related information of the subjects were surveyed using self-reported questionnaire and interview. MetS was identified based on the report of Alberti et al.(2009). As for the data analysis, SPSS 19.0 was used to conduct the descriptive statistic, ANOVA, Pearson correlation coefficient and multiple logistic regression analysis. Results: Daily working hour affects on the lifting heavy objects, running and strenuous exercise(r=-0.137, p<0.01), and total physical function decreased with the increase in age(r=-0.145, p<0.01). Also, obese was significantly associated with genuflection and bend over(r=-0.110, p<0.05). On multiple logistic regression analysis for the diagnostic indices of MetS, occupational standing time were significantly associated with waist circumference(odds ratio=0.885, ${\beta}$ value=-0.122, 95% CI=0.797-0.983, p<0.05) and triglyceride (odds ratio=0.873, ${\beta}$ value=-0.136, 95% CI=0.800-0.953, p<0.01). Conclusions: These results suggest that the working posture may be important risk factor in pathogenesis and growing of MetS and cardiovascular disease.

• Korean Medical Education Review
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• v.15 no.3
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• pp.125-135
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• 2013

Since the establishment of the national medical licensing examination board in 1992, the medical licensing examination system has changed enormously and this has had a number of impacts on examination services. All those reforms were aimed at improving the relevance and reliability of the test. Several attempts of the testing system have appeared in the new examination service, and which have also brought about the changes in the medical school curriculum such as introducing integrated courses instead of traditional subjects, using test scores as a reference to the post-graduation selection test. Some examples of changes in the examination system are as follows: 1) choosing three integrated test subjects and outlines of their reference content instead of 15 academic subjects, 2) adjusting the ratio of multiple choice question items to focus more on the problem solving level, 3) introduction of 'one-best answer' single set and 'extended matching type items, 4) item construction based on real clinical cases and real clinical materials. Recently, a clinical skill test system has been introduced to measure examinees' basic clinical skills competencies. Despite continuing efforts, the examination system still has many issues remaining to be solved. These problems include the differential weighting of test items, appropriate threshold for passing, and practicality of pre-testing to stabilize the passing rate and avoid the hazards of newness and undesirably difficult test items.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2828-2836
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• 2015

Evaluation items were deducted by based on literature materials to supplement the evaluation system of rock cut-slope in national road. Delphi survey of experts were conducted to review the final evaluation items. As a result of reviewing the significance through stepwise multiple linear regression, all of deducted items were statistically significant because these had lower P-value than 0.05. And It was confirmed that the items were selected appropriately as they had relatively similar levels of the weight. In consideration of CVR and reliability both suggested items and existing items, the exclusible items was selected and new items can complement existing evaluation system were added. Finally 18 rock cut-slope evaluation items was deducted.