• Journal of Biosystems Engineering
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• v.40 no.3
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• pp.201-211
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• 2015

Purpose: Designing equipment for processing, sorting, and other post-harvest operations of agricultural products requires information about their physical properties. This study was conducted to investigate some of the mechanical and physical properties of Moringa oleifera L. pods and seeds. Methods: Properties such as the length, width, thickness, bulk density, porosity, mass, static coefficient of friction, and angle of repose were determined as a function of moisture content. Statistical data and force-deformation curves obtained at each loading orientation and moisture level were analyzed for bioyield point, bioyield strength, yield force, rupture point, and rupture strength using a testrometric machine. Result: The basic dimensions (length, width, and thickness) of moringa pods and seeds were found to increase linearly from 311.15 to 371.45 mm, 22.79 to 31.22 mm, and 22.24 to 29.88 mm, respectively, in the moisture range of 12 to 49.5% d.b. The coefficient of friction for both pods and seeds increased linearly with an increase in moisture content on all the surfaces used. The highest value was recorded on mild steel, with 0.581 for pods and 0.3533 for seeds, and the lowest on glass for pods, with a value of 0.501, and of 0.2933 for seeds on galvanized steel. The bioyield and rupture forces, bioyield and rupture energies, and deformation of the pods decreased with an increase in moisture content to a minimum value, then increased with further decrease within the moisture content range, while the yield force increased to a maximum value and then decreased as the moisture content increased. Conclusion: These results will help to determine the most suitable conditions for processing, transporting, and storing moringa pods, and to provide relevant data useful in designing handling and processing equipment for the crop.

• Explosives and Blasting
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• v.34 no.3
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• pp.10-16
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• 2016

Recently, transition from open pit to underground mining in limestone mines is an increasing trend in Korea due to environmental issues such as noise, dust and vibrations caused by crushers and equipment. The severe damages in the surrounding rock mass of underground opening caused by explosive blasting may lead to rock fall hazards or casualties. It is well known that variables which mainly affect blast-induced rock falls in underground mining are: blast vibration level, joint orientation and distribution and shape of the cross sections of underground structures. In this study, UDEC program, which is a DEM code, is used to simulate blast vibration-induced rock fall in underground openings. Variation of joint space, joint angle and joint normal stiffness was considered to investigate the effect of joint characteristics on the blast vibration-induced rock fall in underground opening. Finally, jointed rock mass models considering blast-induced damage zone were examined to simulate the critical blast vibration value which may cause rock falls in underground opening.

• Elastomers and Composites
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• v.40 no.3
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• pp.212-221
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• 2005

Polyurethanes containing mesogen unit (MPU-6) were prepared from 4,4'-diphenylmethane diisocyanate (MDI) and 4,4'-bis(6-hydroxy hexoxy)biphenyl (BP-6) having flexible chain composed of 6 carbons. Intrinsic viscosities of MPU-6s were in the range of $0.23{\sim}0.56 dL/g$. The mesomorphic behaviors of MPU-6 were observed in X-ray and polarizing microscopy analysis. However, MPU-6s demonstrated a 'virtual liquid crystal' behavior, which did not exhibit mesophase on slow heating and slow cooling. MPU-6 having lower molecular weight exhibited higher crystallization rate and melting crystallization temperature due to increased mobility of polymer chains. The increased mobility of polymer chains facilitate the orientation of mesogen units that may act as a nucleating agent.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.4
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• pp.139-146
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• 1987

The 3-dimensional deformation measurement by the terrestrial photogrammetry is consist of 3-dimensional coordinates computation, displaced point detection and deformation estimation of object targets. In this study, at the first step of deformation analysis, the variation of the variance-covariance matrix for the exterior orientation elements was analyzed by the increment of the ground control points and the photos in the Bundle adjustment. And then, to give the constraints for improving accuracy of ground control points, the concept of Free-Network adjustment was applied to Bundle adjustment. As a result, we knew that it was desired in the accuracy and the economy, the observation time when the numbers of ground control point and photo were respectively 6 points and 3 photos. In addition, in the case of applying the concept of Free Network adjustment in Bundle adjutment, it was desirable that the space distance for the constraints is distributed outside.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.275-284
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• 2011

In the process of supply chain management (SCM), the supply chain outside of the production line contributes up to 60~70% of value added. Faced with ever increasing competition, companies are exercising the efforts for cost reduction and process improvement. At the center of the efforts is the reengineering of supply chain for the improvement of customer orientation and customer satisfaction. In spite of the need, the contractual hierarchy with subcontractors stands in the implementation of SCM in the construction industry. Although the construction industry has its own unique characteristics, The process of SCM can be adopted into the industry for improving the effectiveness of the business process. This study presents the methods that can foster SCM professionals through the development of SCM professional education contents, and suggests the activations for applying construction SCM.

• Journal of Korean Elementary Science Education
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• v.22 no.2
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• pp.192-199
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• 2003

The Journal of Korean Elementary Science Education has been developed in both quantitative and qualitative aspects during twenty years since first published year 1983. This study was intended to survey the research trend of the journals, which has been published so far. It will give an orientation of science education research and suggestions towards research to improve science education. The 243 articles of the journals, which were published from 1983 to 2002 by Korean Elementary Science Education Society, were classified into 7 categories including science teaching, science learning, assessment in science, science teacher education, science curriculum, educational facilities & materials, and general science education. The results are as follows: 1. The articles published last decade are increased four times compared with the first decade. 2. The half of articles published so far concentrated on science teaching and learning. The articles on educational facilities & materials or general science education are few. 3. During the last decade, the articles on science teacher education, educational facilities & materials, assessment in science, and science learning relatively increased than the first decade. The number of articles on science curriculum was fluctuated every five years. 4. Most of articles were focused on the narrow subject areas. For example, the articles on science teaching, science learning, assessment in science, science teacher education, science curriculum, and educational facilities & materials were largely focused on the teaching strategies, pupils' conception, affective assessment and teaching practice survey, teachers' appreciation about the nature of science or instruction, analysis of science textbooks, development of the experimental materials or the audiovisual aids respectively. 5. The subject areas highlighted so far in science education, for example, inquiry or experimental activities, STS instruction, environmental education, gifted education, instruction with multimedia, problem-solving or reasoning, experimental skill assessment, etc. were not much researched.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.40-44
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• 2002

Precision correction is the process of geometrically aligning images to a reference coordinate system using GCPs(Ground Control Points). Many applications of remote sensing data, such as change detection, mapping and environmental monitoring, rely on the accuracy of precision correction. However it is a very time consuming and laborious process. It requires GCP collection, the identification of image points and their corresponding reference coordinates. At typical satellite ground stations, GCP collection requires most of man-powers in processing satellite images. A method of automatic registration of satellite images is demanding. In this paper, we propose a new algorithm for automatic precision correction by GCP chips and RANSAC(Random Sample Consensus). The algorithm is divided into two major steps. The first one is the automated generation of ground control points. An automated stereo matching based on normalized cross correlation will be used. We have improved the accuracy of stereo matching by determining the size and shape of match windows according to incidence angle and scene orientation from ancillary data. The second one is the robust estimation of mapping function from control points. We used the RANSAC algorithm for this step and effectively removed the outliers of matching results. We carried out experiments with SPOT images over three test sites which were taken at different time and look-angle with each other. Left image was used to select UP chipsets and right image to match against GCP chipsets and perform automatic registration. In result, we could show that our approach of automated matching and robust estimation worked well for automated registration.

• Geomechanics and Engineering
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• v.19 no.2
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• pp.167-178
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• 2019

Open-pit (OP) and underground (UG) mining are usually used to exploit shallow and deep ore deposits, respectively. When mine deposit starts from shallow subsurface and extends to a great depth, sequential use of OP and UG mining is an efficient and economical way to maintain mining productivity. However, a transition from OP to UG mining could induce significant rock movements that cause the slope instability of the open pit. Based on Yanqianshan Iron Mine, which was in the transition from OP to UG mining, a large-scale two-dimensional (2D) model test was built according to the similar theory. Thereafter, the UG mining was carried out to mimic the process of transition from OP to UG mining to disclose the triggered rock movement as well as to assess the associated slope instability. By jointly using three-dimensional (3D) laser scanning, distributed fiber optics, and digital photogrammetry measurement, the deformations, movements and strains of the rock slope during mining were monitored. The obtained data showed that the transition from OP to UG mining led to significant slope movements and deformations that can trigger catastrophic slope failure. The progressive movement of the slope could be divided into three stages: onset of micro-fracture, propagation of tensile cracks, and the overturning and/or sliding of slopes. The failure mode depended on the orientation of structural joints of the rock mass as well as the formation of tension cracks. This study also proved that these non-contact monitoring technologies were valid methods to acquire the interior strain and external deformation with high precision.

• Journal of People, Plants, and Environment
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• v.21 no.6
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• pp.533-543
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• 2018

This study aimed to examine how the horticultural therapy that was originated in the US has influenced South Korea and Japan and developed in the two countries as an interim check to promote qualitative growth of horticultural therapy with the growing social attention. It also aimed to look into the background of how horticultural therapy was introduced in Japan (which introduced horticultural therapy around the same time as Korea), and the process of the introduction, and compare them with those of Korea in order to set the direction for horticultural therapy. Data was collected to prepare the chronological table of horticultural therapy in Korea and Japan and investigate the flow. Interviews were conducted with the professors who first opened a horticultural therapy course in university so as to determine the introduction background. The analysis results are summarized as follows: Horticultural therapy was created to give mental comfort and emotional purification to those concerned with horticulture that had concerns over social phenomena. In Korea, there had been a process of finding a way of getting mental comfort and emotional purification in the economic slowdown in the late 1990s. Since 2001, there have been more attention and demand for horticultural therapy. As a result, there has been a tendency of studying general horticultural welfare activities and professional horticultural therapy separately. In Japan, the environmental pollution that has arisen since 1970s led to a concern over social orientation in the relation between plants and humans. The academic conference of global researchers to establish the horticultural therapy studies influenced the introduction of horticultural therapy in Korea and Japan. Both countries had no operations and system, and developed them independently. They had similar directions to seek, such as the department of horticultural therapy, need for professional education, active introduction of hospital practice (internship), and security of operating budget. Horticultural therapy has many competencies and thus requires constant research and expansion.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.3
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• pp.206-216
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• 2019

The present study identified several antecedents that create perceived resistance to supply chain management (SCM) change. This work particularly emphasizes SCM change, which is notable given its central role in reacting market orientation and varied environmental and managerial conditions. A careful case study on a small and medium sized food production company in South Korea leads to the formulation of our framework including one second-order construct of 'resistance' as well as eight first-order constructs of 'implementing the payment terms', 'balancing of business process', 'fear of responsibility', 'business sustainability transparency', 'past experience of failure', 'competence of work personnel', 'cooperation with third parties' and 'sharing personnel information with partner'. The hypothesized relation of first- and second-order construct was validated using survey sample data collected from 350 respondents who completed their questionnaire instrument. Results from confirmatory factor analysis revealed that nomological validity was established at statistical significance level by identifying six first order constructs of 'implementing the payment terms', 'fear of responsibility', 'business sustainability transparency', 'past experience of failure', a conbined construct of 'competence of work personnel/cooperation with third parties' and 'sharing personnel information with partner'. The findings from our work are expected to provide important insights to the strategy for SCM risk management for small and medium sized company.