• Journal of Korean Society of Forest Science
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• 제90권4호
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• pp.465-475
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• 2001

Based on the community structural attributes, such as species composition, diameter and height distribution, topographic position, and species diversity in the natural deciduous forest of Mt. Gari area, this study suggested desirable species and composition ratio to achieve ecological management of forests so as to maintain forest stability and enhance economical values. The results are as follows : 1. Twenty-five tree species were growing in the study forest. Of these Quercus mongolica, Pinus densiflora, Juglans mandshurica, Quercus serrata, Cornus controversa, Acer mono, Fraxinus rhynchophylla, and Tilia mandshurica were selected for desirable species through the evaluation of dominant and dominant potential. Kalopanax pictus, considered to be highly valuable species, was also included. 2. Taking account of different species composition pattern by topographic positions, we select as desirable species of J. mandshurica, C. controversa, Q. mongolica, A. mono, T. mandshurica, and F. rhynchophylla in the valley area, Q. mongolica, Q. serrata, A. mono, T. mandshurica, F. rhynchophylla, and K. pictus in the mid-slope area, and Q. mongolica, P. densiflora, Q. serrata, and Fraxinus rhynchophylla in the ridge area. 3. Based on the estimation of species diversity index for the overstory components, the reasonable forest stability levels of the indices were estimated at 1.96, 1.68, 1.94, and 1.27 for whole forest, valley, midslope, and ridge, respectively. 4. The recommended species composition ratios in the study forest were suggested Q. mongolica to be 30%, A. mono, F. rhynchophylla, Q. serrata, and T. mandshurica to be 10%~15%, J. mandshurica, P. densiflora, and C. controversa to be 5%~10%, and K. pictus to be 5%.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1443-1450
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• 2003

Crossbred (Bos taurus${\times}$Bos indicus) calves were used from birth till 14 weeks of age to evaluate three sources of protein that differed in ruminal degradability viz. groundnut cake alone (HD) or in combination with cottonseed meal (MD) and meat and bone meal (LD), when fed along with two sources of non-structural carbohydrates viz. raw (R) and thermally processed (P) maize. Twenty four new born calves were arranged in six groups in a $3{\times}2$ factorial design and fed on whole milk up to 56 d of age. All the different calves received calf startes along with green oats (Avena sativa) from 14 d of age onwards free-choice. A metabolism trial of 6d starters duration, conducted after 90 d of experimental feeding, revealed greater (p<0.05) digestibility of DM, OM, total carbohydrates, NDF and ADF in calves fed on the P diets than on the R diets promoting greater (p<0.05) metabolizable energy intake. The digestibility of NDF was higher (p<0.01) on LD diets where as calves on MD diets exhibited significantly lower digestibility of ADF (p<0.01). The retention of nitrogen per unit metabolic body size was significantly (p<0.05) higher on the LD-P diet than on the diet HD-P which, in turn, was higher (p<0.05) than that of HD-R. Nitrogen retention as percentage of intake was significantly greater (p<0.05) on LD-P than on LD-R diets (52.2 vs. 36.4%). Also, P fed calves utilized nitrogen more efficiently than the R fed as shown by retention of significantly greater proportions of intake (47.4 vs. 40.9%) and absorbed (65.8 vs. 59.5%) nitrogen. Calorimetric evaluation of the diets through open-circuit respiration chamber revealed that the dietary treatments had no impact on methane production by calves. The intake of DE and ME was improved (p<0.01) because of maize processing resulting in greater (p<0.01) retention of energy. The protein degradability exerted no influence on the partitioning or retention of energy. A significant interaction between cereal and protein types was evident with respect to retention of both nitrogen (p<0.01) and energy (p<0.05). In conclusion, no discernible trend in the influence of cereal processing was apparent on the dietary protein degradability, but the positive effect of cereal processing on energy retention diminished with the increase in dietary undegradability.

• Physical Therapy Korea
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• 제25권2호
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• pp.1-12
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• 2018

Background: It is very difficult for hemiplegic patients to effectively perform the sit-to-stand (STS) movements independently because of several factors. Moreover, the analysis of STS motion in hemiplegic patients has been thus far confined to only muscle strength evaluation with little information available on structural and environmental factors of varying chair height and foot conditions. Objects: This study aimed to analyze the change in biomechanical factors (ground reaction force, center of mass displacement, and the angle and moment of joints) of the joints in the lower extremities with varying chair height and foot conditions in hemiplegic patients while they performed the STS movements. Methods: Nine hemiplegic patients voluntarily participated in this study. Their STS movements was analyzed in a total of nine sessions (one set of three consecutive sessions) with varying chair height and foot conditions. The biomechanical factors of the joints in the lower extremities were measured during the movements. Ground reaction force was measured using a force plate; and the other abovementioned parameters were measured using an infra-red camera. Two-way repeated analysis of variance was performed to determine the changes in biomechanical factors in the lower extremities with varying chair height and foot conditions. Results: No interaction was found between chair height and foot conditions (p>.05). All measured variables with varying chair height showed a significant difference (p<.05). Maximum joint flexion angle, maximum joint moment, and the displacement of the center of mass in foot conditions showed a significant difference (p<.05); however the maximum ground reaction force did not show a significant difference (p>.05). Conclusion: The findings suggest that hemiplegic patients can more stably and efficiently perform the STS movement with increased chair height and while they are bare-foot.

• Journal of the Korea Concrete Institute
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• 제29권4호
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• pp.345-351
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• 2017

This study evaluated the effectiveness of V-shaped ties as an alternative to the supplementary crossties specified in ACI 318-14 on the flexural ductility of reinforced concrete columns. From column specimens tested under constant axial loads and reversed cyclic lateral loads, the mode of failure and lateral load-lateral displacement relationship were measured according to the variation of the applied axial load levels. After the columns reached the peak lateral load capacity, the $90^{\circ}$ hooks of the crossties gradually opened, which eventually caused premature buckling of the longitudinal reinforcement and severe crushing of the core concrete, whereas no V-ties were extracted from the core concrete until the column failure. As a result, the cumulative work damage indicators up to 80% of the peak lateral load for V-tie columns under the axial load level of 0.2, 0.4, and 0.55 was as much as 2.4, 2.3, and 5.2 times higher, respectively, than those of the companion crosstie columns. The superiority of the V-ties to the conventional crossties in enhancing the flexural ductility of columns became more prominent as the axial load level increases.

• Journal of the Korean Society for Nondestructive Testing
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• 제36권4호
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• pp.281-287
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• 2016

Fiber Bragg grating (FBG) sensors are applied in structural health monitoring (SHM) in various application fields because of their ease of multiplexing and capability of performing absolute measurements. Moreover, the packaging methods of FBG sensors accelerate their commercialization rapidly. However, long-term SHM exposes the FBG sensors to cyclic thermal loads, and a investigation is required because it finally leads to the signal instability of the FBG sensors. In this study, the effects of sensor packaging methods two methods are generally used for the FBGs: (bonding both sides of the FBG or bonding the FBG directly on signal stability of FBG sensors are investigated. Tests are conducted on specimens in a thermal chamber, over a temperature range from $-20^{\circ}C$ to $60^{\circ}C$ for 300 cycles. Signal characteristics such as Bragg wavelength, light intensity and full width at half maximum are examined and are compared with those of the FBG sensors, obtained in a previous study under direct bonding conditions. From the comparison, it is observed that the FBG sensors with bonding on both sides of the FBG demonstrate higher signal stabilities when exposed to cyclic thermal loads during long-term SHM. Consequently, it guarantees more effectiveness when packaging the FBG sensors.

• Journal of the Korean Society for Nondestructive Testing
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• 제36권5호
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• pp.399-405
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• 2016

Recently, fiber optic sensors, which have many advantages are being applied in various fields by replacing conventional electric sensors. To transmit the light signals between an interrogator and a sensor head, optical components such as an optical adaptor and optical jumper cords are generally used. When signals are transmitted using an adaptor, the end surface of each jumper cord is faced together. If alien substances exist on the core surface of an optical fiber, those can cause light transmission loss and signal disappearance. For this reason, non-contact fiber jumper cords are developed to overcome the problems that require continual attention. The light transmission performance of non-contact fiber jumper cords are also evaluated. From the test results, conventional fiber jumper cords are unable to transmit the signals over 2 mm cavity between the ends of both cords. Otherwise, non-contact fiber jumper cords can transmit the signals with stability up to the cavity of 7 mm though they have more transmission loss than the conventional ones. Consequently, non-contact fiber jumper cords that have better signal stability than conventional ones in environments are highly recommended in field applications, especially if they play a role as a cable for signal transmission between fiber optic sensors.

• Journal of the Korea Institute of Building Construction
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• 제15권6호
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• pp.569-577
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• 2015

Recently, the concept of seismic design has changed from prescriptive to performance based design. For the performance based design with the specified target performance of the structure, it is necessary to execute the inelastic structural analysis to predict precisely the actual behavior of the structure. To address this issue, the seismic performance of the 5-story RC moment-resisting frames designed in accordance with KBC2009 is evaluated through push-over analysis and economic analysis is conducted focused on the direct construction costs. The results show that the ordinary and the intermediate moment-resisting frame are evaluated to meet the required performance design criteria and that the direct construction costs of the two frames are similar. However, although the special moment-resisting frame designed with strong column-weak girder philosophy satisfies the required performance design criteria, the direct construction cost is uneconomical compared with other frames. Therefore, although the intermediate moment-resisting frame of design category D is prohibited in IBC2012, the ordinary and the intermediate moment-resisting frame are estimated to be more reasonable than the special moment-resisting frame for the design of 5-story RC moment-resisting frame.

• Journal of The Korean Association of Information Education
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• 제20권3호
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• pp.293-302
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• 2016

It is the latest fashion of interesting with software education in public school environment and also consider as high priority issue of curriculum for college freshman with programming 101 courses. The block-based programming tool is used widely for the beginner and provides several positive features compare than text-based programming language tools. To measure quality of programming code elaborately which is based script language, it is need to very tough manual process. As a result the previously research related with evaluation of block-based script code has been focused very simple methods in which normalize the number of blocks used which is related with programming concept. In such cases in this, it is difficult to measure structural vulnerability of script code and implicit programming concept which does not expose. In this research, the framework is proposed which enable to measure and evaluate quality of code script of block-based programming tools and also provides method to find of vulnerability of script code. In this framework, the quality metrics is constructed to structuralize implicit programming concept and then developed the quality measure and vulnerability model of script to improve level of programming. Consequently, the proposed methods enable to check of level of programming and predict the heuristic target level.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제16권12호
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• pp.8776-8790
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• 2015

As a follow-up research of a qualitative study conducted by Lee(2015), this study needed to carry out a quantitative research targeting not a group of experts but of working-level staff and verify the validity of the assessment scales. As far as the study learned from an exploratory factor analysis of the preliminary research, these 12 questions that were incorrectly categorized or that presented outliers had to be removed and as a consequence, the researcher of the study was led to an outcome(75 Items) that would correspond to this factor structure which one had temporarily set up. For the next step, in order to carry out a confirmatory factor analysis, the study worked on verification on a four-stage structural equation model with each of the factors which the researcher had established applied by stage. In the end, a result to confirm how the model's goodness of fit eventually increases with the factors which the researcher had set up added was gained and lastly, another outcome to agree to the hair designers' expertise practice model which the researcher had created was obtained. In the meantime, in terms of the assessment scales which this study has discussed, the study assumes that since the scales accepted a self-rating method, it may lead not only to increase in expertise through self-reflection but also to establishment of a rational class system based on results of objective expertise measuring but not of subjective judgment by superiors.

• Journal of the Korean Society of Environmental Restoration Technology
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• 제17권4호
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• pp.29-41
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• 2014

The Korean government has purchased land properties alongside any significant water bodies before setting up the buffers to secure water qualities. Since the annual budgets are limited, however, there has always been the issue of which land parcels ought to be given the priority. Therefore, this study aims to develop efficient mechanism for land acquisition priorities in stream corridors that would ultimately be vegetated for riparian buffer zones. The criteria of land acquisition priority were driven through literary review along with experts' advice. The relative weights of their value and priorities for each criterion were computed using the Analytical Hierarchy Process(AHP) method. Major findings of the study are as follows: 1. The decision-making structural model for land acquisition priority focuses mainly on the reduction of non-point source pollutants(NSPs). This fact is highly associated with natural and physical conditions and land use types of surrounding areas. The criteria were classified into two categories-NSPs runoff areas and potential NSPs runoff areas. 2. Land acquisition priority weights derived for NSPs runoff areas and potential NSPs runoff areas were 0.862 and 0.138, respectively. This implicates that much higher priority should be given to the land parcels with NSPs runoff areas. 3. Weights and priorities of sub-criteria suggested from this study include: proximity to the streams(0.460), land cover(0.189), soil permeability(0.117), topographical slope(0.096), proximity to the roads(0.058), land-use types(0.036), visibility to the streams(0.032), and the land price(0.012). This order of importance suggests, as one can expect, that it is better to purchase land parcels that are adjacent to the streams. 4. A standard scoring system including the criteria and weights for land acquisition priority was developed which would likely to allow expedited decision making and easy quantification for priority evaluation due to the utilization of measurable spatial data. Further studies focusing on both point and non-point pollutants and GIS-based spatial analysis and mapping of land acquisition priority are needed.