• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.91-100
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• 2014

This research was conducted on the conservation area of Baekdudaegan, Kangwondo under the purpose of evaluating bio-diversity according to the changes of spatial scale, using GIS data and spatial filtering method. The diversity index was calculated based on the information of species of The $5^{th}$ forest type map using Shannon-weaver index (H'), evenness index ($E_i$) and richness index ($R_i$). The diversity index was analyzed and compared according to the changes of 12 spatial scales from Kernel size $3{\times}3$ to $73{\times}73$ and basin unit. As for H' and $R_i$, spatial scale increased as diversity index decreased, while $E_i$ decreases gradually. H' and $R_i$ was highest; each 1.1 and 0.6, when the Kernel size was $73{\times}73$, while $E_i$ was 0.2, the lowest. When you look at according to the basin unit, for large basin unit, 'YeongDong' region shows higher diversity index than 'YeongSeo' region. For middle basin unit, 'Gangneung Namdaecheon' region, and for small basin unit, 'Gangneung Namdaecheon' and 'Gangneung Ohbongdaem' region shows high diversity index. When you look at the relationship between diversity index and Geographic factors, H' shows positive relation to curvature and sunshine factor while shows negative to elevation, slope, hillshade, and wetness index. Also $E_i$ was similar to the relationship between H' and Geographic factor. Meanwhile, $R_i$ shows positive relationship to curvature and sunshine factor, while negative to elevation, slope, hillshade, and wetness index. macro unit diversity index evaluation was possible through the GIS data and spatial filtering, and it can be a good source for local biosphere conservation policy making.

• Smart Structures and Systems
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• v.26 no.3
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• pp.331-343
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• 2020

In this paper, based on the CPT, motion equations for a sandwich plate containing a core and two integrated face-sheets have derived. The structure rests on the Visco-Pasternak foundation, which includes normal and shear modules. The piezo-magnetic core is made of CoFe₂O₄ and also is subjected to 3D magnetic potential. Two face sheets at top and bottom of the core are under electrical fields. Also, in order to obtain more accuracy, the effect of flexoelectricity has took into account at face sheets' relations in this work. Flexoelectricity is a property of all insulators whereby they polarize when subject to an inhomogeneous deformation. This property plays a crucial role in small-scale rather than macro scale. Employing CPT, Hamilton's principle, flexoelectricity considerations, the governing equations are derived and then solved analytically. By present work a detailed numerical study is obtained based on Piezoelectricity, Flexoelectricity and modified couple stress theories to indicate the significant effect of length scale parameter, shear correction factor, aspect and thickness ratios and boundary conditions on natural frequency of sandwich plates. Also, the figures show that there is an excellent agreement between present study and previous researches. These finding can be used for automotive industries, aircrafts, marine vessels and building industries.

• Computers and Concrete
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• v.24 no.3
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• pp.207-222
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• 2019

This paper has presented an effective and accurate meso-scale finite element model for simulating the fracture process of concrete under compression-shear loading. In the proposed model, concrete is parted into four important phases: aggregates, cement matrix, interfacial transition zone (ITZ), and the initial defects. Aggregate particles were modelled as randomly distributed polygons with a varying size according to the sieve curve developed by Fuller and Thompson. With regard to initial defects, only voids are considered. Cohesive elements with zero thickness are inserted into the initial mesh of cement matrix and along the interface between aggregate and cement matrix to simulate the cracking process of concrete. The constitutive model provided by ABAQUS is modified based on Wang's experiment and used to describe the failure behaviour of cohesive elements. User defined programs for aggregate delivery, cohesive element insertion and modified facture constitutive model are developed based on Python language, and embedded into the commercial FEM package ABAQUS. The effectiveness and accuracy of the proposed model are firstly identified by comparing the numerical results with the experimental ones, and then it is used to investigate the effect of meso-structure on the macro behavior of concrete. The shear strength of concrete under different pressures is also involved in this study, which could provide a reference for the macroscopic simulation of concrete component under shear force.

• Human Ecology Research
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• v.61 no.3
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• pp.401-414
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• 2023

This study examined the sequential mediation effects of academic achievement attribution and career decision-making self-efficacy on the effect of paternal and maternal helicopter parenting on high-school students' career preparation behavior. A total of 285 (119 male and 166 female) Korean high-school students in the second grade participated in the study. Research variables were measured using the Career Preparation Behavior Scale (Kim, 1997), Helicopter Parenting Scale (LeMoyne & Buchanan, 2011), Attribution Questionnaire (Weiner, 1979), and Career Decision-Making Self-Efficacy Scale-Short Form (Betz et al., 1996). To examine the sequential mediating effect, data analysis was performed using SPSS 29.0 and PROCESS MACRO (v4.2) Model 6. The results revealed no correlations between helicopter parenting and academic failure attribution. However, higher paternal and maternal helicopter parenting were found to indirectly reduce high-school students' career preparation behavior through lower internal academic success attribution (effort and ability) and higher external academic success attribution (task difficulty and luck), which reduced career decision-making self-efficacy. These findings can be employed to develop more effective intervention programs comprising career guidance for adolescents, which emphasizes the negative effect of helicopter parenting. This study expands the research field, as previous findings on helicopter parenting mostly focus on college students.

• Journal of the Korean Geographical Society
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• v.43 no.6
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• pp.894-913
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• 2008

This study examines scale issues in the contemporary feminist migration literature. Scale appears as important, yet poorly understood concept in this field of study. The increasing attention to the feminization of migration requires not only gendered, but also scalar-sensitive approaches. Feminists criticize the conventional approach to the migration as a gender-blind approach that privileges national scale around which migration processes are organized. Claiming multiscalar and interscalar analyses, they propose investigations ranging from macro to micro processes which include globalized gendered division of labor, transnational family networks, and reproduction which takes place in and through the bodies and homes of migrant women. The migrant women, the major actors in recent transnational migration, cross various borders: the national boundaries and the public and private divides, in particular. This crossover can unsettle patriarchal gender relations which have been established based on the physical and symbolic division of nation-states and public/private spheres. Blurring these divisions accompanies social construction of various scales. The transnational family networks of migrant women, for example, show the construction of a transnational scale by migrant women as well as globalization from below. This paper points out misunderstandings of scale in the feminist migration literature and attempts to fill the gaps by introducing the meanings and implications of scales developed mostly by feminist geographers. In so doing, it promotes the interdisciplinary communication.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.56-60
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• 2010

This study was carried out to develop of macro-protocol and the biosafety guide Golden Rice, modified vitamin A at large scale GMO field. Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in the environment and human health. Prior to GM plant release, applicants should provide the information on GM crops for approval. A total of $4,700m^2$ GM field, each of Golden Rice and 'Nakdong' were used for further analysis on agronomic traits and pathogenesis. Generally plant growth and panicle number in the transgenic lines were lower than in the wild type under field condition. The major agronomic traits such as plant growth, grain quality in Golden Rice were similar than in 'Nakdong'. The yield difference was due to reduced ripened rate and the 1,000 grain weight. The grain shape was similar donor plant, however, color of brown rice was different from segregation. Also the difference of pathogenesis reaction was not significant in the leaf blast and sheath blight between Golden Rice and 'Nakdong'. These results provided the agronomic data and pathogenesis for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Korean Journal of Breeding Science
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• v.42 no.2
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• pp.157-162
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• 2010

This study was carried out to develop of macro-protocol and the biosafety guide for 'Nakdong', and 'Golden Rice' (genetically modified vitamin A rice) by large scale field trial of GM crops. Typically, when a new GM crop is created, breeders should conduct field test to make sure the GM crop is safe, and provide some information on GM crops for approval. A total of isolated 4,700 $m^2$ field for trial of GM crops were prepared, and 'Nakdong' and 'Golden rice' were cultivated by standard method of RDA (Rural Development Administration, Korea). Field studies indicated that the population densities of insect pests and natural enemies have no difference between two varieties. While insect pest density on 'Nakdong' was slightly higher than on Golden Rice, but natural enemy density on Golden Rice was a little higher. These results provided the insect diversity for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.2
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• pp.296-320
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• 2014

Since the last decades, livestock ranching has been fast industrialized and the global trade of meat products is sheer increasing. And the Korean government opened its domestic beef market to meet increasing domestic demand for beef. In this context, domestic beef production took its way to specialization and scale economies, and subsequently the commodity chain of beef became different from the conventional one. Such institutions as beef quality grade, HACCP, and brand marketing have strong influence on current beef production systems. Furthermore, along with the macro-scale change, regional and local systems and actors also transform the beef commodity chain. Hampyong-gun, which had once been a declining rural and under-served region in the past, is now actively reviving its economy by producing industrialized, specialized, and localized beef. Such native beef production is both impacted by and associated with multi-scaled actors, their institutions and supporting discourses. These heterogeneous actors and institutions form a newer form of native beef system in the region.

• Transactions on Electrical and Electronic Materials
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• v.14 no.3
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• pp.160-163
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• 2013

We investigated the effect of light intensity and wavelength of a solar cell device by using photoconductive atomic force microscopy (PC-AFM). The $POCl_3$ diffusion doping process was used to produce a p-n junction solar cell device based on a Poly-Si wafer and the electrical properties of prepared solar cells were measured using a solar cell simulator system. The measured open circuit voltage ($V_{oc}$) is 0.59 V and the short circuit current ($I_{sc}$) is 48.5 mA. Also, the values of the fill factors and efficiencies of the devices are 0.7% and approximately 13.6%, respectively. In addition, PC-AFM, a recent notable method for nano-scale characterization of photovoltaic elements, was used for direct measurements of photoelectric characteristics in local instead of large areas. The effects of changes in the intensity and wavelength of light shining on the element on the photoelectric characteristics were observed. Results obtained through PC-AFM were compared with the electric/optical characteristics data obtained through a solar simulator. The voltage ($V_{PC-AFM}$) at which the current was 0 A in the I-V characteristic curves increased sharply up to 1.8 $mW/cm^2$, peaking and slowly falling as light intensity increased. Here, $V_{PC-AFM}$ at 1.8 $mW/cm^2$ was 0.29 V, which corresponds to 59% of the average $V_{oc}$ value, as measured with the solar simulator. Also, while light wavelength was increased from 300 nm to 1,100 nm, the external quantum efficiency (EQE) and results from PC-AFM showed similar trends at the macro scale, but returned different results in several sections, indicating the need for detailed analysis and improvement in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.2
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• pp.39-49
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• 2002

The purpose of this study is to propose an objective and rational methodology for the selection of proposed sites far the National Trust(NT), which is the new alterative proposal far the conservation of natural environments destroyed by injudicious land development and economic growth. That is to enforce many analysis for the effective estimation of rare ecological and landscape resources and to propose a model based on estimation and united indicators. Using the estimative model, we apply it to the selection of the proposed site in micro scale and simultaneously offer the basic methodology of effective and systematic land conservation in macro scale. The results of this study are as follows: 1) The results of analysis for the reliability of estimative items and indicators, presented no problem in that the coefficient of reliability was over 0.7. 2) The correlation measure of the estimative indicator indicated that 'succession'and 'regenerating restorability' were highly correlative in the item of plants. Another three items showed a tendency to be alike. 3) The results of factor analysis on the characteristics of indicators, classified plants into four categories including a stable factor. The item of animals was classified as a stable and rare factor. The item of landscape was classified as a physical and mental factor and the environment as a pollutional and conditional factor. 4) The model of estimation created through factor analysis was valid for the approval of the regression model because significant probability was 0.00. When we consider the NT proposed site as a complex body that is composed of diverse natural and manmade resources, certainly the synthetic methodology of estimation is needed. If these studies are carried out, NT sites will be selected more rationally and effectively than at present. Consequently, they have the potential to play a core role of natural ecosystem conservation in Korea.