• Title/Summary/Keyword: 결정성 분석

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Prediction of Ammonia Emission Rate from Field-applied Animal Manure using the Artificial Neural Network (인공신경망을 이용한 시비된 분뇨로부터의 암모니아 방출량 예측)

  • Moon, Young-Sil;Lim, Youngil;Kim, Tae-Wan
    • Korean Chemical Engineering Research
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    • v.45 no.2
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    • pp.133-142
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    • 2007
  • As the environmental pollution caused by excessive uses of chemical fertilizers and pesticides is aggravated, organic farming using pasture and livestock manure is gaining an increased necessity. The application rate of the organic farming materials to the field is determined as a function of crops and soil types, weather and cultivation surroundings. When livestock manure is used for organic farming materials, the volatilization of ammonia from field-spread animal manure is a major source of atmospheric pollution and leads to a significant reduction in the fertilizer value of the manure. Therefore, an ammonia emission model should be presented to reduce the ammonia emission and to know appropriate application rate of manure. In this study, the ammonia emission rate from field-applied pig manure is predicted using an artificial neural network (ANN) method, where the Michaelis-Menten equation is employed for the ammonia emission rate model. Two model parameters (total loss of ammonia emission rate and time to reach the half of the total emission rate) of the model are predicted using a feedforward-backpropagation ANN on the basis of the ALFAM (Ammonia Loss from Field-applied Animal Manure) database in Europe. The relative importance among 15 input variables influencing ammonia loss is identified using the weight partitioning method. As a result, the ammonia emission is influenced mush by the weather and the manure state.

Development of Sensor Network Simulator using Machine Instruction-level Discrete-Event Simulation (기계명령어-레벨의 이산-사건 시뮬레이션을 이용한 센서 네트워크 시뮬레이터 개발)

  • Jung Yong-Doc;Kim Bang-Hyun;Kim Tae-Kyu;Kim Jong-Hyun
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.769-771
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    • 2005
  • 유비쿼터스 컴퓨팅의 기반 설비인 센서 네트워크는 많은 수의 센서 노드들로 구성되며, 각 센서 노드의 하드웨어는 매우 작은 규모이다. 또한 최소한의 전력 소모를 위하여 센서 노드들은 동적으로 재구성되며, 노드들 간의 통신은 무선 네트워크를 통하여 이루어진다. 센서 네트워크는 구축 목적에 따라 네트워크 토폴로지 및 라우팅 방식이 결정되어야 하고, 이와 더불어 센서 노드의 하드웨어와 소프트웨어도 필요에 따라 다양하게 변경되어야 한다. 따라서 센서 네트워즈가 구현되기 전에 시스템 동작과 성능을 예측할 수 있고 소프트웨어 개발 환경도 제공해주는 시뮬레이터가 사용 가능하다면, 시스템 개발 기간을 크게 단축시킬 수 있을 것이다. 기존의 센서 네트워크 시뮬레이터들은 특별한 응용을 위한 특정 기반의 하드웨어와 운영체제에 국한되어 개발되었기 때문에 다양한 센서 네트워크 환경을 지원하기에는 한계가 있으며, 센서 네트워크 설계상의 주요 요소인 전력 소모량 분석이 포함되지 않았다. 따라서 본 연구에서는 특정한 응용이나 운영체제에 제한을 받지 않으면서 다양하게 센서 네트워크 환경을 설계 및 검증할 수 있고 전력 소모량 추정도 가능한 시뮬레이터를 개발하는 것을 목표로 하였다. 본 연구에서 개발한 시뮬레이터는 기계명령어-레일(machine instruction-level)의 이산-사건 시뮬레이션(discrete-event simulation) 기법을 이용함으로써 실제 센서 노드의 프로그램 실행 및 관련 동작들을 세부적으로 예측하는 데 사용될 수 있도록 하였다. 시뮬레이션의 작업부하(Workload)인 명령어 트레이스(instruction trace)로는 ATmega128L 마이크로컨트롤러용으로 크로스 컴파일된 인텔 헥스-레코드 형식(.hex) 또는 S-레코드 형식(.srec)의 파일을 사용한다.들을 해결하고자 프라이버시보호에 새로운 키 생성 방법을 통한 강력한 프로토콜을 제안 한다.하였으나 사료효율은 증진시켰으며, 후자(사양, 사료)와의 상호작용은 나타나지 않았다. 이상의 결과는 거세비육돈에서 1) androgen과 estrogen은 공히 자발적인 사료섭취와 등지방 침적을 억제하고 IGF-I 분비를 증가시키며, 2) 성선스테로이드호르몬의 이 같은 성장에 미치는 효과의 일부는 IGF-I을 통해 매개될 수도 있을을 시사한다. 약 $70 {\~} 90\%$의 phenoxyethanol이 유상에 존재하였다. 또한, 미생물에 대한 항균력도 phenoxyethanol이 수상에 많이 존재할수록 증가하는 경향을 나타내었다. 따라서, 제형 내 oil tomposition을 변화시킴으로써 phenoxyethanol의 사용량을 줄일 수 있을 뿐만 아니라, 피부 투과를 감소시켜 보다 피부 자극이 적은 저자극 방부시스템 개발이 가능하리라 보여 진다. 첨가하여 제조한 curd yoghurt는 저장성과 관능적인 면에서 우수한 상품적 가치가 인정되는 새로운 기능성 신제품의 개발에 기여할 수 있을 것으로 사료되었다. 여자의 경우 0.8이상이 되어서 심혈관계 질환의 위험 범위에 속하는 수준이었다. 삼두근의 두겹 두께는 남녀 각각 $20.2\pm8.58cm,\;22.2\pm4.40mm$으로 남녀간에 유의한 차이는 없었다. 조사대상자의 식습관 상태는 전체 대상자의 $84.4\%$가 대부분이 하루 세끼 식사를 규칙적으로 하고 있었으며 식사속도는 허겁지겁 빨리 섭취하는 경우가 남자는 $31.0\%$, 여자는 $21.4\%$로 나타났고 이들을 제외한 나머지 사람들은 보통 속도 혹은 충분한 시간을 가지고 식사를 하였

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Optimization of the Community Energy Supply System for D-Cube City, Multi Purpose Building (복합건물(D-Cube City) 지역에너지 공급체계 최적화)

  • Lee, Tae-Won;Kim, Yong-Ki;Lee, Kun-Woo;Lee, Ki-Bong;Cho, Dong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.6
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    • pp.669-674
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    • 2012
  • D-Cube City is a recently completed multi purpose building consisting of four types of facilities; offices, a department store, a hotel, and congregation spaces. A community energy supply system(CES) has been installed to supply this building with electricity, steam, heat, and cold water. The BEMS, building energy management system, is currently being designed to reduce building energy consumption through the efficient operation of the various pieces of building service equipment. In this study the optimal methods for operating the CES of D-Cube City were considered. This system includes three combined heat and power systems, seven steam boilers, two hot water boilers, two absorption chillers, and four turbo chillers, and various other pieces of equipment. In result, the optimal methods of operating the CES for various energy demand levels were obtained along with the seasonal effects on the economic efficiency of the operation. The effect of the amount of energy demanded by the various facility areas on the total energy consumption was also analyzed.

Seismic Performance Assessment of Unreinforced Masonry Wall Buildings Using Incremental Dynamic Analysis (증분동적해석을 통한 비보강 조적벽식 건물의 내진성능 평가)

  • Kwon, Ki Hyuk;Kim, Man Hoe;Kim, Hyung Joon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.3
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    • pp.28-39
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    • 2013
  • The most common housing type in Korea is low-rise buildings with unreinforced masonry walls (UMWs) that have been known as a vulnerable seismic-force-resisting system (SFRS) due to the lack of ductility capacities compared to high lateral stiffness of an UMW. However, there are still a little experimental investigation on the shear strength and stiffness of UMWs and on the seismic performance of buildings using UMWs as a SFRS. In Korea, the shear strength and stiffness of UMWs have been evaluated with the equations suggested in FEMA 356 which can not reflect the structural and material characteristics, and workmanship of domestic UMW construction. First of all, this study demonstrates the differences in shear strength and stiffness of UMWs obtained from between FEMA 356 and test results. The influence of these differences on the seismic performance of UMW buildings is then discussed with incremental dynamic analyses results of a prototype UMW building that were selected by the site survey of more than 200 UMW buildings and existing test results of UMWs. The seismic performance assessment of the prototype UMW building are analyzed based on collapse margin ratios and beta values repesenting uncertainty of seismic capacity. Analysis results show that the seismic performance of the UMW building estimated using the equations in FEMA 356 underestimates both a collapse margin ratio and a beta value compared to that estimated by test results. Whatever the estimation is carried out two cases, the seismic performance of the prototype building does not meet the criteria prescribed in a current Korean seismic code and about 90% collapse probability presents for more than 30-year-old UMW buildings under earthquakes with 2400 return years.

Selective Phase Transformation of Arsenopyrite by Microwave Heating and their Enhancement Au Recovery by Thiocyanate Solution (마이크로웨이브 가열에 의한 황비철석의 선택적 상변환과 티오시안산염 용액에 의한 Au 회수율 향상)

  • Han, Oh-Hyung;Kim, Bong-Ju;Cho, Kang-Hee;Choi, Nag-Choul;Park, Cheon-Young
    • Journal of the Mineralogical Society of Korea
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    • v.27 no.2
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    • pp.73-83
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    • 2014
  • In order to investigate selective phase transformations and to determine the maximum Au leaching factors from microwave treated Au-bearing complex sulfides, a microscope, SEM-EDS analysis, and thiocyanate leaching tests were performed. When the Au-bearing complex sulfides were exposed to microwave heating, increasing the microwave exposure time increased temperature and decreased weight. Arsenopyrite was first selectively transformed to hematite, which formed a concentric rim structure. In this hematite, oxygen and carbon was detected and always showed high iron content and low arsenic content due to arcing and oxidation from microwave heating. The results of the leaching test using microwave treated sample showed that the maximum Au leaching parameters was reached with 0.5 g concentration thiocyanate, 2.0 M hydrochloric acid, 0.3 M copper sulfate and leaching temperature at$60^{\circ}C$. Under the maximum Au leaching conditions, 59% to 96.69% of Au was leached from the microwave treated samples, whereas only 24.53% to 92% of the Au was leached from the untreated samples.

The Change of Market Competition After Import Liberalization of Petroleum Products (석유제품 수입자유화 이후 시장경쟁의 변화)

  • Kim, Jin Hyung
    • Environmental and Resource Economics Review
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    • v.12 no.4
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    • pp.637-661
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    • 2003
  • This paper analyzes the impact of import liberalization of petroleum product market in 1997 on the behavior of a domestic industry, regarded as a typical oligopoly. Based on the theory of implicit cartel, two regression equations were formulated and estimated for domestic production and refinery margin using monthly data for the period from Jan. 1994 to June 2003. Estimation results show that not only did domestic production rise sharply but also the refining cost fell substantially throughout 1996 before the actual liberalization of imports, Such a response is clearly consistent with the implicit cartel theory, which suggests that once the difficulty of maintaining a cartel in the future is recognized, the cartel immediately collapses and anticipation of import liberalization can cause immediately lowering market price as well as an immediate expansion of the supply by a domestic industry. However, the significant reduction of refinery cost accompanied by a large contraction in domestic output after the actual implementation of import liberalization can be explained by the collapse of implicit cartel caused by the anticipated liberalization of imports. Thus, import liberalization in the sense of allowing entry of foreign producers into domestic market has seemed to be an effective means to weaken market power and induce more competitive conduct of domestic firms.

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Denitrification Rates in Tributaries of the Han River in Relation to Landuse Patterns and Microtopology (한강 지류 토지 이용 특성과 하천 내의 미지형에 따른 탈질량과 조절 인자)

  • Kim, Young-Joo;Kwon, Min-Jung;Kang, Ho-Jeong
    • Journal of Wetlands Research
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    • v.14 no.1
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    • pp.139-146
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    • 2012
  • Stream ecosystems carry out significant functions such as water purification, especially denitrification. However, rapid landuse change since industrialization has altered ecological functions of streams. In this study, we aimed to investigate denitrification rates and their determinant factors in streams with different landuse patterns, and how denitrification rates vary with microtopology within streams. Ten fifth streams of each landuse were selected, and each stream was divided into four microtopological sites within streams - riparian zone, subsoil, and both head and tail parts of sand bars. In situ denitrification rates and physicochemical properties of soil were examined. Denitrification rates of agricultural, urban, and forest streams were $289.62{\pm}70.69$, $157.01{\pm}37.06$, $31.38{\pm}18.65mg$ $N_2O-N\;m^{-2}\;d^{-1}$ respectively. There were no significant differences in denitrification rates depending on microtopology, but the rates in riparian zone were the highest, and the rates in the head parts of sandbars were lower than those of tail parts. The determinant factors for denitrification rates included water temperature, silt and clay contents of soil, inorganic nitrogen, and organic carbon, and these factors all showed positive correlations with denitrification rates. Through this study, we find that landuse pattern in watershed region affects denitrification rates that is one of considerable functions of streams. In addition, estimation of denitrification rates taking into account for microtopology would contribute to developing ecological management and restoration strategy of streams.

A Perception of Beginning Earth Science Teachers on Porphyritic Texture (반상조직에 대한 초임 지구과학교사들의 인식)

  • Kim, Yong-Hwan;Chung, Duk-Ho;Cho, Kyu-Seong;Choi, Jin-A;Park, Kyeong-Jin
    • Journal of the Korean earth science society
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    • v.32 no.7
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    • pp.860-870
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    • 2011
  • This study is to explore the Pedagogical Content Knowledge of beginning earth science teachers about the porphyritic texture of igneous rocks, and to suggest the teaching device that can prevent a trial and error of students in earth science instruction. We developed an interview guideline concerned with basic perception on the porphyritic texture, formation condition and formation process of porphyritic rocks, teaching and learning on porphyritic rocks for it. And data was collected from 5 beginning earth science teachers (3 high schools, 2 middle schools) through a group discussion method. In result, despite the porphyritic texture can be found at hypabyssal rocks as well as volcano rocks and plutonic rocks, most beginning earth science teachers cognized that it could be found at hypabyssal rocks only by focusing the formation depth of hypabyssal rocks. Also, the formation of porphyritic texture should be considered the factors such as cooling rate, nucleation density, growth rate, growth time, etc. However they mainly reflected the formation temperature and growth rate as it's parameter. Participants have wrongly perceived that a phenocryst necessarily differs from a groundmass on chemical composition. And they are inclined to discriminate phenocryst from groundmass through their chemical differences, instead of grain size.

Changes in height and inclination of the articular eminence during the growth period (성장기에서 관절융기 높이 및 경사의 연령적 변화)

  • Choi, Dong-Soon;Jang, In-San;Cha, Bong-Knen
    • The korean journal of orthodontics
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    • v.40 no.6
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    • pp.411-420
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    • 2010
  • Objective: The purpose of this study was to assess the changes in height and inclination of the articular eminence during the growth period. Methods: One hundred and sixty subjects (71 males and 89 females) with a normal skeletal pattern and TMJ function, ranging in age from 5.9 to 19.7 years were divided according to their chronological age into six groups. Lateral individualized corrected TMJ tomograms were taken of all subjects, and the height and inclination of the articular eminence were measured. UNIANOVA was used to compare the differences between the age groups. Mann-Whitney test was used to compare the differences between male and female subjects. Results: The height and the inclination of the articular eminence were increased and became steeper with age, and the height and the inclination were larger in male than in female subjects. Conclusions: Dynamic changes in the height and the inclination of the articular eminence were observed during the growth period, therefore a full understanding of the growth of the articular eminence is important for orthodontic and orthopedic treatment in this period.

Forecasting Brown Planthopper Infestation in Korea using Statistical Models based on Climatic tele-connections (기후 원격상관 기반 통계모형을 활용한 국내 벼멸구 발생 예측)

  • Kim, Kwang-Hyung;Cho, Jeapil;Lee, Yong-Hwan
    • Korean journal of applied entomology
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    • v.55 no.2
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    • pp.139-148
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    • 2016
  • A seasonal outlook for crop insect pests is most valuable when it provides accurate information for timely management decisions. In this study, we investigated probable tele-connections between climatic phenomena and pest infestations in Korea using a statistical method. A rice insect pest, brown planthopper (BPH), was selected because of its migration characteristics, which fits well with the concept of our statistical modelling - utilizing a long-term, multi-regional influence of selected climatic phenomena to predict a dominant biological event at certain time and place. Variables of the seasonal climate forecast from 10 climate models were used as a predictor, and annual infestation area for BPH as a predictand in the statistical analyses. The Moving Window Regression model showed high correlation between the national infestation trends of BPH in South Korea and selected tempo-spatial climatic variables along with its sequential migration path. Overall, the statistical models developed in this study showed a promising predictability for BPH infestation in Korea, although the dynamical relationships between the infestation and selected climatic phenomena need to be further elucidated.