• 산업기술연구
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• 제27권B호
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• pp.103-107
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• 2007

In this paper, the light screen sensing system is introduced and testified to detect small grains such as seeds or electronic chips of uneven sized. Two modules composed of transmitter-receiver sensor array and microprocessor-based sensor signal processing system are developed to realize the proposed system. Experimental results showed that the sensing signal was relatively clear and its counting performance was very stable.

• 농촌지도와개발
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• 제3권1호
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• pp.157-164
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• 1996

The public sector extension services in which governments of less developed countries (LDCs) have invested large sums often at the behest of donors are achieving uneven impact, often at unsustainable high costs. Further, the fundamental premise of public sector extension - that low-income farmers are unlikely to obtain technical information unless it is provided by government - increasingly requires re-examination. This paper reviews the pressures facing conventional agricultural extension, examines the prospects of recent approaches that are participatory, institutionally pluralistic and geared towards cost-sharing, and suggests ways forward for governments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1389-1391
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• 2003

The development of wind turbine power generation has grown during the past ten years. An important question, when installing wind turbines with the generator connected directly to the grid, is holt much the voltage quality will be affected by the uneven power production and by the connection of the wind turbine to the grid. This paper presents the voltage fluctuation of grid-connected WTG(wind turbine generators) by MATLAB/Simulink.

• Journal of Electrical Engineering and Technology
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• 제11권5호
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• pp.1433-1440
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• 2016

• 한국균학회지
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• 제46권4호
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• pp.491-494
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• 2018

A new species of Graphis is described from Cameroon, Africa. The new taxon is distinguished by a greyish-green, glossy, uneven, and continuous thallus. Further, it possesses stellately branched lirellae, and its entire labia are covered almost completely with thick thalline margin. It also has a completely carbonized proper exciple, which is considerably thick at the base, one-spored asci, and muriform hyaline to yellowish ascospores.

• 융합신호처리학회논문지
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• 제14권2호
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• pp.124-129
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• 2013

6족 보행 로봇은 2족 또는 4족 보행 로봇에 비하여 안정적인 보행이 가능한 장점이 있다. 따라서 6족 보행 로봇은 이러한 보행의 안정성을 기반으로 다양한 지능적인 동작을 수행하기에 유리한 구조이다. 본 논문에서는 전형적인 6족 보행 로봇과는 달리 로봇의 진행 방향에 대하여 전후 다리와 좌우에 각각 한 쌍의 다리를 갖는 6족 보행 로봇을 제안하고 제안된 로봇을 사용하여 다양한 지능형 동작을 수행한다. 26개의 모듈형 모터를 사용하여 로봇 기구부를 구성하고 호스트 PC, DSP 주제어기, AVR 보조 제어기, 스마트폰/스마트패드로 구성되는 제어기를 구현한다. 구현된 로봇은 스테레오 카메라, 적외선 센서, 초음파 센서, 접촉 센서 등 다양한 센서 데이터를 사용하여 비평탄면 보행, 공차기, 원격 제어 및 3차원 모니터링 등 다양한 지능형 동작을 수행할 수 있음을 실험을 통하여 검증한다.

• World Technopolis Review
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• 제1권3호
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• pp.192-205
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• 2012

Globalization has fuelled the desire for simplicity and flexibility in rules and processes within nations. de Soto (2000) calls for the simplification of rules to enable people to join the formal economy. Friedman (2005) echoes the need for simpler rules, to attract business and capital. Market-based approaches to governing have been adopted in many nations due to globalization. Recent developments demonstrate that such approaches fail. Globalization may lead to impoverishment in the absence of proper forms of governance (Cooney 2000). That is why it has the tendency to become a "race to the bottom." Regulatory measures can be costly, and the costs of doing business are uneven across nations. This unevenness is being used as a comparative advantage. Others call this regulatory competition (Smith-Bozek 2007) or competitive governance (Schachtel and Sahmel 2000), which is similar to the model of Charles Tiebout. Collaborative governance is an approach that governments could use in lieu of the competitive method. Mechanisms that enable stakeholders to exchange information, harmonize activities, share resources, and enhance capacities (Himmelman 2002) are needed. Philippine public policy encourages a shift in modes of realizing labor market governance outcomes from command to collaboration (Sale and Bool 2010B; Sale 2011). Is labor market governance and regional development in the Philippines collaborative? Or is the opposite - competitive governance (Tiebout model) - more evident? What is the dominant approach? This preliminary research tackles these questions by looking at recent data on average and minimum wages, wage differentials, trade union density, collective bargaining coverage, small and bigger enterprises, employment, unemployment and underemployment, inflation, poverty incidence, labor productivity, family income, among others, across regions of the country. The issue is studied in the context of legal origins. Cultural explanations are broached.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.86.2-86.2
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• 2010

In order to improve polymer electrolyte membrane fuel cell (PEMFC) durability, the durability of membrane electrode assemblies (MEA), in which the electrochemical reactions actually occur, is one of the vital issues. Many articles have dealt with catalyst layer degradation of the durability-related factors on MEAs in relation to loss of catalyst surface area caused by agglomeration, dissolution, migration, formation of metal complexes and oxides, and/or instability of the carbon support. Degradation of catalyst layer during long-term operation includes cracking or delamination of the layer which result either from change in the catalyst microstructure or loss of electronic or ionic contact with the active surface, can result in apparent activity loss in the catalyst layer. Membrane degradation of the durability-related factors on MEAs can be caused by mechanical or thermal stress resulting in formation of pinholes and tears and/or by chemical attack of hydrogen peroxide radicals formed during the electrochemical reactions. All of these effects, the mechanical damage of membrane and degradation of catalyst layers are more facilitated by uneven stress or improper MEA fabrication process. In order to improve the PEMFC durability, therefore, it is most important to minimize the uneven stress or improper MEA fabrication process in the course of the fabrication of MEA. We analyzed the effects of the MEA fabrication condition on the PEMFC durability with MEA produced using CCM (catalyst coated membrane) method. This paper also investigated the effects of MEA fabrication condition on the PEMFC durability by adding additional treatment process, hot pressing and pressing, on the MEA produced using CCM method.

• Structural Engineering and Mechanics
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• 제73권2호
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• pp.191-207
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• 2020

This study aims at investigating the size-dependent free vibration of porous nanoplates when exposed to hygrothermal environment and rested on Kerr foundation. Based on the modified power-law model, material properties of porous functionally graded (FG) nanoplates are supposed to change continuously along the thickness direction. The generalized nonlocal strain gradient elasticity theory incorporating three scale factors (i.e. lower- and higher-order nonlocal parameters, strain gradient length scale parameter), is employed to expand the assumption of second shear deformation theory (SSDT) for considering the small size effect on plates. The governing equations are obtained based on Hamilton's principle and then the equations are solved using an analytical method. The elastic Kerr foundation, as a highly effected foundation type, is adopted to capture the foundation effects. Three different patterns of porosity (namely, even, uneven and logarithmic-uneven porosities) are also considered to fill some gaps of porosity impact. A comparative study is given by using various structural models to show the effect of material composition, porosity distribution, temperature and moisture differences, size dependency and elastic Kerr foundation on the size-dependent free vibration of porous nanoplates. Results show a significant change in higher-order frequencies due to small scale parameters, which could be due to the size effect mechanisms. Furthermore, Porosities inside of the material properties often present a stiffness softening effect on the vibration frequency of FG nanoplates.

• 한국환경복원기술학회지
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• 제18권6호
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• pp.39-49
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• 2015

This study was to evaluate the growth and spatial distribution characteristics of Rhus javanica population. The study was conducted between 2015 January and July at the cut-slope revegetation site in Dae-Ji Mountain. Seeds of native species were sowed on the disturbed cut-slope in 2002. There were 119 vascular plant species 55 families and 94 genera on the cut-slope. Compositae, Rosaceae, and Leguminosae plants were dominant species, which are pioneer species in dry and barren site. Canopy of trees covered 44.1% total area, which was 8.3% increase from 2008. Rhus javanica, main species, dominated all DBH classes except DBH >24cm. Albizzia julibrissin showed high frequency in the 6~17cm DBH class and Salix koreensis was abundant at >12cm. Elaeagnus umbellata, Corylus heterophylla var. heterophylla, Alnus sibirica, and Acer pictum were not observed. Rhus javanica population was the most frequently observed on the south facing cut-slope. The average DBH of Rhus javanica was $7.3({\pm}3.7)cm$ and the average height of them was $5.2({\pm}1.7)m$. Annual average DBH growth was 7.9mm/yr and the maximum growth(12.0mm/yr) was the $3^{rd}$ year. It decreased after $6^{th}$ years. Although Rhus javanica population in the Dae-Ji Mountain was a seed originated plantation, the forest had reverse J shape diameter frequency distribution. It indicated that the forest is uneven-aged forest. The Rhus javanica population was expected to sustain.