• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.581-586
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• 1998

We investigated the effect of mechanical back side damage in Czochralski grown silicon wafer. The intensity of mechanical damage was evaluated by minority carrier recombination lifetime by laser excitation/microwave reflection photoconductivity decay method, degree of X-ray diffuse scattering, X-ray section topography, and wet oxidation/preferential etching methods. The data indicate that the higher the mechanical damage intensity, the lower the minority carrier lifetime, and the magnitude of diffuse scattering and X-ray excess intensity increased proportionally, and it was at Grade 1:Grade 2:Grade 3=1:7:18.4 that the normalized relative quantization ratio of excess intensity in damaged wafer was calculated, which are normalized to the excess intensity from sample Grade 1.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.105-118
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• 2015

PURPOSES : This study aims to evaluate the road safety of the super-elevation transition section of a left turn curve and suggest the minimum longitudinal grade of a super-elevation transition section to be used before and after a left curved section. METHODS : We evaluated the road condition by means of the safety-criterion-evaluation method involving side friction factors, and then solve the problem by introducing the minimum longitudinal grade criterion based on conditions described in the hydraulics literature. RESULTS : It was calculated that when a road satisfies hydroplaning conditions, the difference between side friction assumed and side friction demanded is less than -0.04. In this case, the safety criterion for the condition is unsatisfied. Conversely, when a road is in a normal state under either wet or dry conditions, it was calculated that the difference between side friction assumed and side friction demanded is more than 0.01. Thus, the safety criterion for this condition is found to be satisfied. After adjusting the minimum longitudinal grade applied to a super-elevation transition section, the hydroplaning condition can be eliminated and the safety criterion can be met for all sections. CONCLUSIONS : It is suggested that a minimum longitudinal grade should be provided on super-elevation transition sections in order to prevent hydroplaning.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.53-58
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• 2009

The importance of process for repair and reinforcement of the bridge is increasing because of the lack of the fatigue load and stress, a lowering of the bridge load carrying capacity owing to impact and oscillation, deterioration on cultivation periods of the bridge, etc. Typically the experimenter values the bridge load carrying capacity by the real rating factor and response modification factor in bridge load rating through static load test and dynamic load test. But the error occurred in reliability of response modification factor in bridge load rating according to experience of experimenter. so tests of connecting probability theory and valuation of the bridge recently. The study is to compute the real load carrying capacity of the bridge and the rating factor and response modification factor on grade of the bridge, and calculate the probability of over-loaded truck load from Weigh In Motion(WIM) Data in FORTRAN programming applying to Monte-Carlo Simulation. At the result of this study, it is acquired that the new grade is computed for the probability of over-loaded truck load and surface inspection. The A grade is over 1.95, B grade is $1.55{\sim}1.94$, C grade is $1.26{\sim}1.54$, D grade is $1.14{\sim}1.25$, E grade is under 1.13 of rating factor, respectively.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.569-577
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• 2000

The position of tobacco leaves is affluence to the quality. To evaluate its quality, sample leaves was collected according to the position of attachment. In Korea, the position was divided into four classes such as high, middle, low and inside positioned leaves. Until now, the grade of standard sample was determined by human expert from korea ginseng and tobacco company. Many research were done by the chemical and spectrum analysis using NIR and computer vision. The grade of tobacco leaves mainly classified into 5 grades according to the attached position and its chemical composition. In high and low positioned leaves shows a low level grade under grade 3. Generally, inside and medium positioned leaf has a high level grade. This is the basic research to develop a real time tobacco leaves grading system combined with portable NIR spectrum analysis system. However, this research just deals with position recognition and grading using the color machine vision. The RGB color information was converted to HSI image format and the sample was all investigated using the bundle of tobacco leaves. Quality grade and position recognition was performed through well known general error back propagation neural network. Finally, the relationship about attached leaf position and its grade was analyzed.

• Journal of Science Education
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• v.45 no.1
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• pp.1-10
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• 2021

In this study, we analyzed the relationship between the physical science domain of TIMSS 2019 and the Korean science curriculum. Twelve subjects are presented in the physical science domain of the TIMSS 2019 4th grade evaluation framework. Research group consisting of elementary and middle school teachers and science education experts, a total of 12, participated to analyze in which grade these subjects were included in the Korea 2009 revised and 2015 revised science curriculum. As a results of analyzing whether the achievement standards of the TIMSS 2019 evaluation framework and Korean science curriculum are consistent, the subjects pertinent to chemistry like 'chemical changes in everyday life,' 'heat transfer,' and 'electricity and simple electrical circuits' appeared not covered at all until the 4th grade curriculum in Korea. Given that the TIMSS 2019 evaluation framework is an international achievement standard, we are proposing to improve the Korean curriculum as follows: first, for the development of the next science curriculum, there is a need for science curriculum organized from the 1st grade of elementary school to connect the content and scope of chemistry in elementary, middle, and high schools as a whole including the Nuri curriculum. Second, as an alternative to the problem of suitability of learning volume and level of learning, it is possible to think of a method to readjust the grade of dealing with related concepts by lowering the difficulty or simplifying the concept. Third, it is necessary to discuss about introducing essential concepts and standard terms into Korea science curriculum according to international trends.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.148-160
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• 2012

The main purpose of this paper is to deliver a climate analysis and evaluation method based on GIS by using airborne LiDAR data and Biotop type map and to provide spatial information of climate analysis and evaluation based on Biotop type Map. At first stage, the area, slope, slope length, surface, wind corridor function and width, and obstacle factors were analyzed to obtain cold/fresh air production and wind corridor evaluation. In addition, climate evaluation was derived from those two results in the second stage. Airborne LiDAR data are useful in wind corridor analysis during the study. Correlation analysis results show that ColdAir_GRD grade was highly correlated with Surface_GRD (-0.967461139) and WindCorridor_ GRD was highly correlated with Function_GRD (-0.883883476) and Obstacle_GRD (-0.834057656). Climate Evaluation GRID was highly correlated with WindCorridor_GRD (0.927554516) than ColdAir_GRD (0.855051646). Visual validations of climate analysis and evaluation results were performed by using aerial ortho-photo image, which shows that the climate evaluation results were well related with in-situ condition. At the end, we applied climate analysis and evaluation by using Biotop map and airborne LiDAR data in Gwangmyung-Shiheung City, candidate for the Bogeumjari Housing District. The results show that the aerial percentile of the 1st Grade is 18.5%, 2nd Grade is 18.2%, 3rd Grade is 30.7%, 4th Grade is 25.2%, and 5th Grade is 7.4%. This study process provided both the spatial analysis and evaluation of climate information and statistics on behalf of each Biotop type.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.82-90
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• 2009

It is very important to utilize effectively fibrous waste paper in terms of cost savings, environmental effects, and governmental policies. The quality of final products and runnability of papermaking process are primarily affected by constitutions of fibrous raw materials. In specific, board grade paper depends directly on compositions of waste paper bales. At present, the raw materials of board grade paper are mainly derived from lots kinds of wastepaper. Some papermaking countries, like EU, USA and Japan have advanced classification and management systems of recycled fiber, but Korea has not yet organized systematically. In this study, evaluation of wastepaper bale compositions and their fiber properties were carried out for effective utilization of fibrous raw materials for board grade paper production. 3 kinds of wastepaper bales were classified to fibrous or non-fibrous materials. In case of fibrous materials, KOCC, kraft sack paper and white duplex board matters were main component in total weight basis, and in case of non-fibrous materials, vinyl, plastic and cloth matters were main component, in turns. 3 representative kinds of waste paper were disintegrated and classified, and then prepared to handsheet for evaluation of recycled fiber property. Consequently, fines and ash content of waste paper, isolated from KOCC and white duplex board were higher than that of kraft sack paper. pH values of all kinds of waste fibers were neutral or weak alkaline.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.4
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• pp.393-399
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• 2008

The reduction of the Vehicle interior noise has been the main interest of NVH engineers. The driver's perception on the vehicle noise is affected largely by psychoacoustic characteristic of the noise as well as the SPL. The previous methods to evaluation of the SQ about vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of the subjective SQ values by neural network. But these are so depended on jury test very much that they result in many difficulties. So, to reduce jury test weight, we suggested a new method using Mahalanobis distance for SQ evaluation. And, optimal characteristic values influenced on the result of the SQ evaluation were derived by signal to noise ratio(SN ratio) of the Taguchi method. Finally, the new method to evaluate SQ is constructed using Mahalanobis-Taguchi system(MTS). Furthermore, the MTS method for SQ evaluation was compared by the result of SQ grade table at the previous study and their virtues and faults introduced.

• KIEAE Journal
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• v.11 no.6
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• pp.29-35
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• 2011

This study aims to suggest improvement plans and explain about the current situation for facilitating Long-life housing, based on the results on flexibility items among 27 items consisting the "Housing Performance Grading System". From the 9th of January, 2006 to the month of July in 2011, study has analyzed evaluation results on 216 different types for each grade and reviewed evaluation criteria and methods. Current evaluation criteria applies quantitative analysis, by calculating in percentage how much bearing walls and columns, which hinder flexibility, take up space in the household. The evaluation rate for each household was assessed in relation to its structural system, and a higher grade was given to column-typed structures. In addition, to facilitate long-life housing, this study extracted harmful factors, expanding the range of evaluation. The first step was to evaluate structure, which is the basic element. The second step can to evaluate the probability of applying resources in response to the changes of structural systems. As The third step, Flexibility item will evaluate the probability of moving the water-using area, suggesting gradual approach. Thus, through evaluations of flexibility items, the study aims to improve the quality of life in household, by avoiding uniform structures and acquiring more freedom for space designs.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.1
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• pp.1-13
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• 2008

This study review of Compositional Evaluation Items for Environmental Conservation Value Assessment Map (ECVAM) in Korea. The ECVAM is composed of legal assessment and environmental/ecological assessment items. ECVAM basically adapts an overlay method for environmental/ecological assessment items. The objective of this study is to suggest supplementary items for the ECVAM with the following process : Overlapping rates of the assessment items in the ECVAM are calculated to understand the grade distribution of the environmental conservation value assessment and to analyze the overlapping rates among the assessment items, as a result it is found that various items are overlapped each other. In order to reflect effectively each assessment item to the ECVAM, Analyzed the overlapping degree among assessment items to be applied to this map. On the concrete we gripped results to be assessed by various items, which were overlapped each other. In order to reflect effectively each assessment item to the environmental conservation value assessment map of national land, we analyzed the overlapping degree on environmental/ecological items, and investigated the grade distribution by field survey. In this study we assessed the ECVAM by 5 kinds of method. Method 1 is Grade 1 areas of each administrative district, Method 2 is Comparing overlapping areas of each assessment items Grade 1, 2 and Permission of each assessment items' duplication, Method 3 is Grade 1, 2 areas by only singular assessment items, Method 4 is Only Grade 1 areas of Method 2 and Method 5 is Only Grade 2 areas of Method 2. As results, Method 1 showed Seoul and other metropolitan cities reveal a high proportion of Grade I regions by the legal assessment items. Kangwon-Do, show a high proportion of Grade I regions by the environmental/ecological assessment item. Method 2 showed 93.4% of diameter Grade II(standard for stability), forest diameter item was accounted for 99.9% by Method 3, Method 4 showed 95.7% of forest diameter and forest density was accounted for 66.4% by Method 5. From now on, this study will contribute to reduce the complexity in the process of manufacturing ECVAM of National Land, and to raise the pliability in the process of managing and updating this map.