• Title/Summary/Keyword: optimum regions

Search Result 211, Processing Time 0.032 seconds

Analysis of Surplus Solar Energy in Greenhouse Based on Setting Temperature (설정온도별 온실내 잉여 태양에너지 분석)

  • Yoon, Yong-Cheol;Kown, Sun-Ju;Kim, Hyeon-Tae;kim, Young-Joo;Suh, Won-Myung
    • Journal of agriculture & life science
    • /
    • v.46 no.1
    • /
    • pp.195-206
    • /
    • 2012
  • This study is about an analysis of surplus solar energy by important greenhouse types as well as setting temperature different by using Typical Meteorological Year data which was secured in order to provide basic data for designing an optimum thermal storage system to accumulate surplus solar energy generating in greenhouses during the daytime. Depending on the setting temperatures of $15{\sim}19^{\circ}C$ for greenhouse heating during day and night, surplus heat amounts were varied at the rate of about $0.2{\sim}6.9%/4^{\circ}C$ with some variations according to the greenhouse types and regions. On the other hand, the variations of supplemental heat requirements were about $29.7{\sim}50.0%/4^{\circ}C$. Depending on the setting temperatures for greenhouse ventilations(low $25{\sim}29^{\circ}C$ and high $27{\sim}31^{\circ}C$), surplus heat amounts were varied at the rate of about $-9.9{\sim}-35.6%/4^{\circ}C$ in auto-type greenhouse. But in single-type greenhouses, they were about $-5.1{\sim}-13.4%/4^{\circ}C$. There were not significant changes in supplemental heat amounts depending on setting temperatures of ventilation for both greenhouse types and regions.

Climate Change in Corn Fields of the Coastal Region of Ecuador

  • Borja, Nicolas;Cho, Jaepil;Choi, KyungSook
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2015.05a
    • /
    • pp.271-271
    • /
    • 2015
  • The Ecuadorian coast has two different climate regions. One is humid region where the annual rainfall is above 2000 mm and rain falls in almost all months of the year, and the other is dry region where the annual rainfall can fall below 50 mm and rainfall can be very seasonal. The agriculture is frequently limited by the seasons during the year and the availability of rainfall amounts. The corn fields in Ecuador are cultivated during the rainy season, due to this reason. The weather conditions for optimum development of corn growth require a monthly average rainfall of 120 mm to 140 mm and a temperature range of $22^{\circ}C{\sim}32^{\circ}C$ for the dry region, and a monthly average rainfall of 200 mm to 400 mm and a temperature range of $25^{\circ}C{\sim}30^{\circ}C$ for the humid area. The objective of this study is to predict how the weather conditions are going to change in corn fields of the coastal region of Ecuador in the future decades. For this purpose, this study selected six General Circulation Models (GCM) including BCC-CSM1-1, IPSL-CM5A-MR, MIROC5, MIROC-ESM, MIROC-ESM-CHEM, MRIC-CGC3 with different climate scenarios of the RCP 4.5, RCP 6.0, and RCP 8.5, and applied for the period from 2011 to 2100. The climate variables information was obtained from the INAMHI (National Institute of Meteorology and Hydrology) in Ecuador for the a base line period from 1986 to 2012. The results indicates that two regions would experience significant changes in rainfall and temperature compared to the historical data. In the case of temperature, an increment of $1^{\circ}C{\sim}1.2^{\circ}C$ in 2025s, $1.6^{\circ}C{\sim}2.2^{\circ}C$ in 2055s, $2.1^{\circ}C{\sim}3.5^{\circ}C$ in 2085s were obtained from the dry region while less increment were shown from the humid region with having an increment of $1^{\circ}C$ in 2025s, $1.4^{\circ}C{\sim}1.8^{\circ}C$ in 2055s, $1.9^{\circ}C{\sim}3.2^{\circ}C$ in 2085s. Significant changes in rainfall are also projected. The rainfall projections showed an increment of 8%~11% in 2025s, 21%~33% in 2055s, and 34%~70% in 2085s for the dry region, and an increment of 2%~10%, 14%~30% and 23%~57% in 2025s, 2055s and 2085s decade respectively for humid region.

  • PDF

A Deep-Learning Based Automatic Detection of Craters on Lunar Surface for Lunar Construction (달기지 건설을 위한 딥러닝 기반 달표면 크레이터 자동 탐지)

  • Shin, Hyu Soung;Hong, Sung Chul
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.38 no.6
    • /
    • pp.859-865
    • /
    • 2018
  • A construction of infrastructures and base station on the moon could be undertaken by linking with the regions where construction materials and energy could be supplied on site. It is necessary to detect craters on the lunar surface and gather their topological information in advance, which forms permanent shaded regions (PSR) in which rich ice deposits might be available. In this study, an effective method for automatic detection of lunar craters on the moon surface is taken into consideration by employing a latest version of deep-learning algorithm. A training of a deep-learning algorithm is performed by involving the still images of 90000 taken from the LRO orbiter on operation by NASA and the label data involving position and size of partly craters shown in each image. the Faster RCNN algorithm, which is a latest version of deep-learning algorithms, is applied for a deep-learning training. The trained deep-learning code was used for automatic detection of craters which had not been trained. As results, it is shown that a lot of erroneous information for crater's positions and sizes labelled by NASA has been automatically revised and many other craters not labelled has been detected. Therefore, it could be possible to automatically produce regional maps of crater density and topological information on the moon which could be changed through time and should be highly valuable in engineering consideration for lunar construction.

Analysis of the Behavior Characteristics of Pile Foundations Responding to Ground Deformation (지반 변형 대응형 말뚝 기초의 거동 특성 분석)

  • Lee, Junwon;Shin, Sehee;Lee, Haklin;Kim, Dongwook;Lee, Kicheol
    • Journal of the Korean Geosynthetics Society
    • /
    • v.19 no.4
    • /
    • pp.21-32
    • /
    • 2020
  • As the global large-scale infrastructure construction market expands, the construction of civil engineering structures in extreme environments such as cold or hot regions is being planned or constructed. Accordingly, the construction of the pile foundation is essential to secure the bearing capacity of the upper structure, but there is a concern about loss of stability and function of the pile foundation due to the possibility of ground deformation in extreme cold and hot regions. Therefore, in this study, a new type of pile foundation is developed to respond with the deformation of the ground, and the ground deformation that can occur in extreme cold and hot region is largely divided into heaving and settlement. The new type of pile foundation is a form in which a cylinder capable of shrinkage and expansion is inserted inside the steel pipe pile, and the effect of the cylinder during the heaving and settlement process was analyzed numerically. As a result of the numerical analysis, the ground heaving caused excessive tensile stress of the pile, and the expansion condition of the cylinder shared the tensile stress acting on the pile and reduced the axial stress acting on the pile. Ground settlement increased the compressive stress of the pile due to the occurrence of negative skin friction. The cylinder must be positioned below the neutral point and behave in shrinkage for optimum efficiency. However, the amount and location of shrinkage and expansion of cylinder must comply with the allowable displacement range of the upper structure. It is judged that the design needs to be considered.

Seismic Vulnerability Assessment and Mapping for 9.12 Gyeongju Earthquake Based on Machine Learning (기계학습을 이용한 지진 취약성 평가 및 매핑: 9.12 경주지진을 대상으로)

  • Han, Jihye;Kim, Jinsoo
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.6_1
    • /
    • pp.1367-1377
    • /
    • 2020
  • The purpose of this study is to assess the seismic vulnerability of buildings in Gyeongju city starting with the earthquake that occurred in the city on September 12, 2016, and produce a seismic vulnerability map. 11 influence factors related to geotechnical, physical, and structural indicators were selected to assess the seismic vulnerability, and these were applied as independent variables. For a dependent variable, location data of the buildings that were actually damaged in the 9.12 Gyeongju Earthquake was used. The assessment model was constructed based on random forest (RF) as a mechanic study method and support vector machine (SVM), and the training and test dataset were randomly selected with a ratio of 70:30. For accuracy verification, the receiver operating characteristic (ROC) curve was used to select an optimum model, and the accuracy of each model appeared to be 1.000 for RF and 0.998 for SVM, respectively. In addition, the prediction accuracy was shown as 0.947 and 0.926 for RF and SVM, respectively. The prediction values of the entire buildings in Gyeongju were derived on the basis of the RF model, and these were graded and used to produce the seismic vulnerability map. As a result of reviewing the distribution of building classes as an administrative unit, Hwangnam, Wolseong, Seondo, and Naenam turned out to be highly vulnerable regions, and Yangbuk, Gangdong, Yangnam, and Gampo turned out to be relatively safer regions.

Estimate of Manganese and Iron Oxide Reduction Rates in Slope and Basin Sediments of Ulleung Basin, East Sea (동해 울릉분지 퇴적물에서 망간산화물과 철산화물 환원율 추정)

  • Choi, Yu-Jeong;Kim, Dong-Seon;Lee, Tae-Hee;Lee, Chang-Bok
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.14 no.3
    • /
    • pp.127-133
    • /
    • 2009
  • In order to determine organic carbon oxidation by manganese and iron oxides, six core sediments were obtained in slope and basin sediments of Ulleung Basin in East Sea. The basin sediments show high organic carbon contents (>2%) at the water depths deeper than 2,000 m; this is rare for deep-sea sediments, except for those of the Black Sea and Chilean upwelling regions. In the Ullleung Basin, the surface sediments were extremely enriched by Manganese oxides with more than 2%. Maximum contents of Fe oxides were found at the depth of $1{\sim}4cm$ in basin sediments. However, the high level of Mn and Fe oxides was not observed in slope sediment. Surface manganese enrichments (>2%) in Ulleung Basin may be explained by two possible mechanisms: high organic carbon contents and optimum sedimentation rates and sufficient supply of dissolved Manganese from slope to the deep basin. Reduction rates of iron and manganese oxides ranged from 0.10 to $0.24\;mmol\;m^{-2}day^{-1}$ and from 0.30 to $0.57\;mmol\;m^{-2}day^{-1}$, respectively. In Ulleung Basin sediments, $13{\sim}26%$ of organic carbon oxidation may be linked to the reduction of iron and manganese oxides. Reduction rates of metal oxides were comparable to those of Chilean upwelling regions, and lower than those of Danish coastal sediments.

Optimum Design of Junctionless MOSFET Based on Silicon Nanowire Structure and Analysis on Basic RF Characteristics (실리콘 나노 와이어 기반의 무접합 MOSFET의 최적 설계 및 기본적인 고주파 특성 분석)

  • Cha, Seong-Jae;Kim, Kyung-Rok;Park, Byung-Gook;Rang, In-Man
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.47 no.10
    • /
    • pp.14-22
    • /
    • 2010
  • The source/channel/drain regions are formed by ion implantation with different dopant types of $n^+/p^{(+)}/n^+$ in the fabrication of the conventional n-type metal-oxide-semiconductor field effect transistor(NMOSFET). In implementing the ultra-small devices with channel length of sub-30 nm, in order to achieve the designed effective channel length accurately, low thermal budget should be considered in the fabrication processes for minimizing the lateral diffusion of dopants although the implanted ions should be activated as completely as possible for higher on-current level. Junctionless (JL) MOSFETs fully capable of the the conventional NMOSFET operations without p-type channel for enlarging the process margin are under researches. In this paper, the optimum design of the JL MOSFET based on silicon nanowire (SNW) structure is carried out by 3-D device simulation and the basic radio frequency (RF) characteristics such as conductance, maximum oscillation frequency($f_{max}$), current gain cut-off frequency($f_T$) for the optimized device. The channel length was 30 run and the design variables were the channel doping concentration and SNW radius. For the optimally designed JL SNW NMOSFET, $f_T$ and $f_{max}$ high as 367.5 GHz and 602.5 GHz could be obtained, respectively, at the operating bias condition $V_{GS}$ = $V_{DS}$ = 1.0 V).

Molecular Cloning and Characterization of Trehalose Biosynthesis Genes from Hyperthermophilic Archaebacterium Metallosphaera hakonesis

  • Seo, Ju-Seok;An, Ju-Hee;Baik, Moo-Yeol;Park, Cheon-Seok;Cheong, Jong-Joo;Moon, Tae-Wha;Park, Kwan-Hwa;Choi, Yang-Do;Kim, Chung-Ho
    • Journal of Microbiology and Biotechnology
    • /
    • v.17 no.1
    • /
    • pp.123-129
    • /
    • 2007
  • The trehalose $({\alpha}-D-glucopyranosyl-[1,1]-{\alpha}-D-glucopyranose)$ biosynthesis genes MhMTS and MhMTH, encoding a maltooligosyltrehalose synthase (MhMTS) and a maltooligosyltrehalose trehalohydrolase (MhMTH), respectively, have been cloned from the hyperthermophilic archaebacterium Metallosphaera hakonesis. The ORF of MhMTS is 2,142 bp long, and encodes 713 amino acid residues constituting a 83.8 kDa protein. MhMTH is 1,677 bp long, and encodes 558 amino acid residues constituting a 63.7 kDa protein. The deduced amino acid sequences of MhMTS and MhMTH contain four regions highly conserved for MTSs and three for MTHs that are known to constitute substrate-binding sites of starch-hydrolyzing enzymes. Recombinant proteins obtained by expressing the MhMTS and MhMTH genes in E. coli catalyzed a sequential reaction converting maltooligosaccharides to produce trehalose. Optimum pH of the MhMTS/MhMTH enzyme reaction was around 5.0 and optimum temperature was around 70 C. Trehalose-producing activity of the MhMTS/ MhMTH was notably stable, retaining 80% of the activity after preincubation of the enzyme mixture at $70^{\circ}C$ for 48 h, but was gradually abolished by incubating at above $85^{\circ}C$. Addition of thermostable $4-{\alpha}-glucanotransferase$ increased the yield of trehalose production from maltopentaose by 10%. The substrate specificity of the MhMTS/MhMTH-catalyzed reaction was extended to soluble starch, the most abundant maltodextrin in nature.

Solubilization of Insoluble Phosphates by Penicillium sp. GL-101 Isolated from Soil (토양에서 분리한 Penicillium sp. GL-101에 의한 난용성 인산염의 가용화)

  • Choi, Myoung-Chul;Chung, Jong-Bae;Sa, Tong-Min;Lim, Sun-Uk;Kang, Sun-Chul
    • Applied Biological Chemistry
    • /
    • v.40 no.4
    • /
    • pp.329-333
    • /
    • 1997
  • Phosphate solubilizing microorganisms (1,000 bacteria and 200 fungi) were isolated from soil around Kyungnam and Kyungbook regions using potato dextrose agar-calcium phosphate medium. A fungus with the greatest phosphate solubilizing activity was selected and identified to Penicillium sp. GL-101, based on the morphological characteristics of conidiophore and conidia; flask shape of phialide, simple branching type of conidiophore, and columnar shape of conidial head, in malt extract agar and potato dextrose agar media. The optimum temperature and initial pH to solubilize rock phosphate in potato dextrose broth-rock phosphate medium were $25^{\circ}C$ and pH 7.5, respectively. In these optimum conditions, phosphate solubilizing activities of Penicillium sp. GL-101 against four types of insoluble phosphate: tricalcium-phosphate, aluminium phosphate, hydroxyapatite and rock phosphate, were quantitatively determined. As results, this fungus highly discharged free phosphates to the culture broth with the concentrations of 1,152 ppm against tricalcium-phosphate, 565 ppm against rock phosphate, 292 ppm against aluminium phosphate, and 217 ppm against hydroxyapatite, respectively.

  • PDF

Marina Development on the Importance of Optimum Demand and Location Selection Study (마리나 개발 적정수요와 입지선정의 중요도에 관한 연구)

  • Lee, Jae-Hyung
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.18 no.5
    • /
    • pp.406-415
    • /
    • 2012
  • The research aims to provide its results to each municipal corporation after an in-depth analysis of its optimum demand and also the significance of post-development location selection. The research results, related to the future development of Marina from the municipal corporation, are as follows: There are approximately 49 proper domestic demands after the Marina development. In further detail, there must be a development of the coastal zone Marina concept after classifying the regions to their Metropolitan areas and networking the Marina to each section. Moreover, the classification of the Marinas to small, medium, and large size is of absolute necessity. Regionally, 10 large Marinas must be developed for metropolitan area (2), Chungcheong area (1), Jeolla area (2), Gyeongsang Provinces (3), Gangwon area (1), and Jeju (1). The 17 mid-sized leisure sports Marinas must be developed for metropolitan area (3), Chungcheong area (2), Jeolla area (2), Gyeongsang Provinces (6), Gangwon area (2), and Jeju (2). The rest of 22 small Marinas must be developed for metropolitan area (2), Chungcheong area (1), Jeolla area (6), Gyeongsang Provinces (9), Gangwon area (2), and Jeju (2). In addition, there is an evident result of significant importance in the domestic positions of appropriate Marina development. A group of professionals suggested five key factors contributed to the importance including accessibility, marketability, usability, validity, and natural environment. The results, aimed to show comprehensive importance based on the five factors, ranks in the following order from highest to lowest: usability, accessibility, natural environment, marketability, and validity.