• 제목/요약/키워드: Linear Region

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An Analysis of the Impact of ODA Projects on Food Security -Focusing on Terai Region, Nepal- (ODA 프로젝트를 통한 식량안보 개선 효과 분석 -네팔 떠라이 지역을 중심으로-)

  • Bae, Jooncheol;Kim, Taeeun;Ji, Seongtae
    • Journal of Korean Society of Rural Planning
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    • v.30 no.3
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    • pp.37-53
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    • 2024
  • The purpose of this study is to analyze the effectiveness of an agriculture and rural development ODA project in southern Nepal's Terai region to improve food security, and to suggest appropriate project approaches to improve food security. The subject of the analysis is the KOICA-funded 'Inclusive Rural Development project', and a framework for analyzing food security was established based on the FAO's four pillars of food security, and indicators were proposed to measure the food security of project farmers. The data for this study were obtained from a survey of project beneficiary farmers and their control group, and the effects of the project on food security were measured using a a t-test analysis, difference-in-difference analysis, propensity score matching-linear regression combined model (PSM-OLS) and a propensity score matching-difference-in-difference combined model(PSM-DID). The results showed that, in general, the ODA project treatment group had significant improvements in each of the four pillars of food security (food availability, access, utilization, and stability). In addition, cooperative membership had a positive impact on food security improvements, and there were also differences in outcomes among different ethnic groups in the Terai region. The implications of this study are that the Korean government's ODA policy should set aside the food security sector and incorporate food security indicators to contribute to the improvement of food security in ODA partner countries, and that agricultural and rural development ODA projects should include food security indicators as performance indicators in their pre-planning to contribute to securing food security for vulnerable groups as food insecurity is higher among vulnerable groups.

Study of new adsorption isotherm model and kinetics of dissolved organic carbon in synthetic wastewater by granular activated carbon (입상활성탄에 의한 합성폐수의 용존유기물질의 새로운 흡착등온 모델 및 운동학적 흡착 연구)

  • Kim, Seoung-Hyun;Shin, Sunghoon;Kim, Jinhyuk;Woo, Dalsik;Lee, Hosun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.4
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    • pp.2029-2035
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    • 2014
  • In this study, we conducted the adsorption equilibrium and batch experiments of dissolved organic carbon (DOC) in the wastewater by granular activated carbon (GAC). The components of organic compound were Beef extract (1.8 mg/L), Peptone (2.7 mg/L), Humic acid (4.2 mg/L), Tannic acid (4.2 mg/L), Sodium lignin sulfonate (2.4 mg/L), Sodium lauryle sulfate (0.94 mg/L), Arabic gum powder (4.7 mg/L), Arabic acid (polysaccharide) (5.0 mg/L), $(NH_4)_2SO_4$ (7.1 mg/L), $K_2HPO_4$ (7.0 mg/L), $NH_4HCO_3$ (19.8 mg/L), $MgSO_4{\cdot}7H_2O$ (0.71 mg/L), The adsorption characteristics of DOC in synthetic wastewater was described using the mathematical model through a series of isotherm and batch experiments. It showed that there was linear adsorption region in the low DOC concentration (0~2.5 mg/L) and favorable adsorption region in high concentration (2.5~6 mg/L). The synthetic wastewater used was prepared using known quantities of organic and/or inorganic compounds. Adsorption modelling isotherms were predicted by the Freundlich, Langmuir, Sips and hybrid isotherm equations. Especially, hybrid isotherm of Linear and Sips equation was a good adsorption equilibrium in the region of the both the low concentration and high concentration. In applying carbon adsorption for treating water and wastewater, hybrid adsorption equation plus linear equation with Sips equation will be a good new adsorption equilibrium model. Linear driving force approximation (LDFA) kinetic equation with Hybrid (linear+Sips) adsorption isotherm model was successfully applied to predict the adsorption kinetics data in various GAC adsorbent amounts.

Incase of Same Region Treatment by using a Tomotherapy and a Linear Accelerator Absorbed Dose Evaluation of Normal Tissues and a Tumor (토모테라피와 선형가속기를 이용한 동일 부위의 치료 시 종양 및 정상조직의 흡수선량 평가)

  • Cheon, Geum-Seong;Kim, Chang-Uk;Kim, Hoi-Nam;Heo, Gyeong-Hun;Song, Jin-Ho;Hong, Joo-Yeong;Jeong, Jae-Yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.22 no.2
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    • pp.97-103
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    • 2010
  • Purpose: Treating same region with different modalities there is a limit to evaluate the total absorbed dose of normal tissues. The reason is that it does not support to communication each modalities yet. In this article, it evaluates absorbed dose of the patients who had been treated same region by a tomotherapy and a linear accelerator. Materials and Methods: After reconstructing anatomic structure with a anthropomorphic phantom, administrate 45 Gy to a tumor in linac plan system as well as prescribe 15 Gy in tomotherapy plan system for make an ideal treatment plan. After the plan which made by tomoplan system transfers to the oncentra plan system for reproduce plan under the same condition and realize total treatment plan with summation 45 Gy linac treatment plan. To evaluate the absorbed dose of two different modalities, do a comparative study both a simple summation dose values and integration dose values. Then compare and analyze absorbed dose of normal tissues and a tumor with the patients who had been exposured radiation by above two differents modalities. Results: The result of compared data, in case of minimum dose, there are big different dose values in spleen (12.4%). On the other hand, in case of the maximum dose, it reports big different in a small bowel (10.2%) and a cord (5.8%) in head & neck cancer patients, there presents that oral (20.3%), right lens (7.7%) in minimum dose value. About maximum dose, it represents that spinal (22.5), brain stem (12%), optic chiasm (8.9%), Rt lens (11.5%), mandible (8.1%), pituitary gland (6.2%). In case of Rt abdominal cancer patients, there represents big different minimum dose as Lt kidney (20.3%), stomach (8.1%) about pelvic cancer patients, it reports there are big different in minimum dose as a bladder (15.2%) as well as big different value in maximum dose as a small bowel (5.6%), a bladder (5.5%) in addition, making treatment plan it is able us to get. Conclusion: In case of comparing both simple summation absorbed dose and integration absorbed dose, the minimum dose are represented higher as well as the maximum dose come out lower and the average dose are revealed similar with our expected values data. It is able to evaluate tumor & normal tissue absorbed dose which could had been not realized by treatment plan system. The DVH of interesting region are prescribed lower dose than expected. From now on, it needs to develop the new modality which are able to realize exact dose distribution as well as integration absorbed dose evaluation in same treatment region with different modalities.

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The Strategies for Forming Governance System to Raise Industrial Competitiveness of Metal and Machinery Industrial Clusters in South-East Region, Korea (동남권 기계.금속산업클러스터의 광역적 지원체계 구축전략)

  • Kwon, O--Hyeok
    • Journal of the Economic Geographical Society of Korea
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    • v.9 no.3
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    • pp.297-317
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    • 2006
  • This article is aimed to find a more successful way to build a metropolitan-wide governance for enhancing industrial cluster in South-East region, Korea. We begin a research with reviewing a current study of regional cluster and its governance. New industrial system and agglomeration changed regional growth theory and urban system. In traditional system, a central city dominated economy of the metropolitan area. However, with development of new transportation and communication technology, a central city lost their superiority to suburban cities. In other words, growing competition between central and suburban cities changed traditional concentration and diffusion theory of urbanization which dominated urban geography for last decades. Next, current situation of development of industrial cluster in South-East region is examined to suggest policy for more competitiveness. South-East region has grown as the most prominent cluster of mechanical engineering and metal industry in Korea since the late 1970s. In the form of agglomeration and network of a specific and its related industry, South-East region has formed a linear industrial belt along with the inter-regional South Coast Highway and contain about ten industrial cities. Accompanying with this growing South-East region, a problem has risen from geographic mismatch between metropolitan-wide industrial cluster and its administrative boundary. Since industrial cluster has no specific administrative boundary, adequate government support for developing industrial cluster has not been provided. Responding to the problem, academics and policy makers maintain need in establishing a metropolitan-wide governance for supporting a cluster. At the end, this paper provides some implication to planners and policy makers.

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Acoustic Analysis of KSR-III Combustion Chamber with Various 5-Blade Baffles under Non-Reacting Condition (5-블레이드 배플이 설치된 로켓엔진 연소실에서의 상온음향 해석)

  • Kim, Hong-Jip;Kim, Seong-Ku;Sohn, Chae-Hoon
    • 한국연소학회:학술대회논문집
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    • 2003.05a
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    • pp.167-171
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    • 2003
  • Acoustic characteristics of baffled combustion chamber to elucidate suppressing effect of baffle on combustion instability are numerically investigated by linear acoustic analysis. A hub-blade baffle of 5 blades is selected as a candidate one and five variants of baffles with various configuration are designed. Resonant-frequency shift and damping factor are analyzed quantitatively as damping parameters. When the hub is located radially at the pressure node, the decrease of resonant frequency and increase of damping factor in 1R mode are dominant. But sub-1T mode is formed within hub, therefore, there would be a possibility of initiating 1T mode in unbaffled region, which would occur another problem. For smaller hub size, four kinds of axial baffle length is selected. As the axial baffle length increases, resonant frequency shift and increase of damping factor of transverse acoustic modes is obtained. Especially, two close acoustic modes such as 1L and 1T could be overlapped for a certain axial length, resulting in extreme increase of damping factor. The present study based on linear acoustic analysis is expected to be a useful confirming tool to predict acoustic field and design a passive control devices such as baffle and acoustic cavity.

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Analysis of the Determinants on the Annual Average Price Rising Rate for Pyeong of Apartment Housing in Seoul (서울지역 아파트 평당 연평균 가격상승률 결정요인 분석)

  • Kil, Ki-Suck;Lee, Joo-Hyung
    • Journal of the Korean housing association
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    • v.18 no.3
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    • pp.63-72
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    • 2007
  • The purpose of this study is to identify the impact of the building, site, and region characteristic factors on the annual average price rising rate of apartment housing in Seoul. The data were consisted of 272 apartment units in Seoul. A survey included checking the drawing documents and interview with apartment maintenance staffs and real estate agencies from October 2006 to February 2007. Data were analyzed with descriptives, frequency, crosstabs, and linear regression by SPSS/PC for Window. The linear regression model was employed to evaluate the price rising rate in apartment housing. Following results were obtained. The price rising rate for pyeong ($3.3m^2$) of apartment housing was determinated by the district zone, the construction company's brand name, the building age, the building stories, the floor space index, the building-to-land ratio, the green space rate, and the distance from the downtown. Especially, the district zone was the most important factor that affected the price rising of apartment housing in Seoul. Therefore, the policy has to focus to solve the imbalance between autonomous districts with the collaborated tax.

Non-linear Temperature Dependent Deformation Anaysis of CBGA Package Assembly Using Moir′e Interferometry (모아레 간섭계를 이용한 CBGA 패키지의 비선형 열변형 해석)

  • 주진원;한봉태
    • Journal of the Microelectronics and Packaging Society
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    • v.10 no.4
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    • pp.1-8
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    • 2003
  • Thermo-mechanical behavior of a ceramic ball grid array (CBGA) package assembly are characterized by high sensitive moire interferometry. Moir fringe patterns are recorded and analyzed at various temperatures in a temperature cycle. Thermal-history dependent analyses of global and local deformations are presented, and bending deformation (warpage) of the package and shear strain in the rightmost solder ball are discussed. A significant non-linear global behavior is documented due to stress relaxation at high temperature. Analysis of the solder interconnections reveals that inelastic deformation accumulates on only eutectic solder fillet region at high temperatures.

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Essence of thermal convection for physical vapor transport of mercurous chloride in regions of high vapor pressures

  • Kim, Geug-Tae;Lee, Kyong-Hwan;Choi, Jeong-Gil
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.6
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    • pp.231-237
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    • 2007
  • For an aspect ratio (transport length-to-width) of 5, Pr=3.34, Le=0.078, Pe=4.16, Cv=1.01, $P_B=50$ Torr, only thermally buoyancy-driven convection ($Gr=4.83{\times}10^5$) is considered in this study in spite of the disparity in the molecular weights of the component A ($Hg_2Cl_2$) and B which would cause thermally and/or solutally buoyancy-driven convection. The crystal growth rate and the maximum velocity vector magnitude are decreased exponentially for $3{\le}Ar{\le}5$, for (1) adiabatic walls and (2) the linear temperature profile, with a fixed source temperature. This is related to the finding that the effects of side walls tend to stabilize convection in the growth reactor. The rate for the linear temperature profiles walls is slightly greater than for the adiabatic walls far varied temperature differences and aspect ratios. With the imposed thermal profile, a fixed source region, both the rate and the maximum velocity vector magnitude increase linearly with increasing the temperature difference for $10{\le}{\Delta}T{\le}50K$.

A Study on the Robust Control of Horizontal-Shaft Magnetic Bearing System Considering Perturbation (불확실성을 고려한 횡축형 자기 베어링 시스템의 로버스트 제어에 관한 연구)

  • Kim, Chang-Hwa;Jung, Byung-Gun;Yang, Joo-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.34 no.1
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    • pp.92-101
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    • 2010
  • Recently, the magnetic bearings which have many advantages such as no noise, less mechanical friction are widely applied to the suspension of rotors on the rotary machineries. However, the magnetic bearing system is inherently unstable, nonlinear and MIMO(multi-input-multi-output) system as well. In this paper, we design a state feedback controller using linear matrix inequality(LMI) to the multi-objective synthesis, for the magnetic bearing system with integral type servo system. The design objectives include $H_{\infty}$ performance, asymptotic disturbance rejection, and time-domain constraints on the closed-loop pole location. The results of computer simulation show the validity of the designed controller.

Design of robust servo systems and application to control of training simulator for radio-controlled helicopter (강인한 서보계설계와 R/C헬리콥터 트레이닝 시뮬레이터 제어에의 응용)

  • 김상봉;박순실
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.2
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    • pp.497-506
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    • 1991
  • In this paper, a new construction for training simulator of R/C helicopter based on two types of servo controller is proposed. Two modified algorithms (algorithm I and II) for servo controller design are presented. Algorithm I is developed by adopting Davison's method in the case that the expressions for the homogeneous differential equations of reference input and disturbance are different types, and algorithm II is done by considering error weighting function for the servo controller of algorithm I . The linear fractional transformation method is incorporated in both design methods in order to assign the closed loop poles of the servo system in a specified region. The helicopter simulator is composed by the gimbals with two freedom of rolling and pitching. The reliability and validity for the design methods of the proposed servo controller are investigated through the practical experiment for the simulator by using 16bits micro-computer with A/D and D/A converters. It can be observered from the experimental results that the proposed servo controller is applicable to practical plants since the simulator is robust for the arbitrary disturbance and it follows to the given reference input without significant steady state error.