• Title/Summary/Keyword: Special-plant

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Long-term Loads based on Evaluation of Resistance and Seakeeping Performances for a Desalination Plant Ship (해상 이동형 해수담수화 플랜트 선박의 저항 및 내항 성능 평가에 따른 장기 하중 추정)

  • Lee, Jae-bin;Paik, Kwang-Jun;Choung, Joonmo
    • Journal of Ocean Engineering and Technology
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    • v.33 no.6
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    • pp.632-640
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    • 2019
  • Desalination plant ships have been recently regarded as one of the probable solutions for drought seasons in many countries. Because desalination plants should be mounted on the desalination ships and special purpose storages such as salty waste water tanks are necessary, onboard and compartment arrangements would be distinguished from those of other conventional commercial ships. This paper introduces some basic design procedure including resistance/propulsion and seakeeping performances. The ship lines were improved step by step after modification of the ship lines and verification of resistance/propulsion performances using computational fluid dynamics (CFD). After finalization of the ship lines, the seakeeping performance was also evaluated to check motion behaviors and drive wave-induced loads such as the wave shear force and bending moment. It was proved that the predicted long-term vertical wave shear force and bending moment were significantly less than the rule-based ones, thus it is expected that the deliverables of this study will reduce the construction cost of desalination plant ships.

Vegetation and Habitat Environment of Sageretia thea in Jeju Island (제주지역 상동나무의 자생지 생육환경 및 식생조사)

  • Song, Sang Churl;Song, Chang Khil;Kim, Ju Sung
    • Korean Journal of Medicinal Crop Science
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    • v.22 no.4
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    • pp.301-305
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    • 2014
  • This study was carried out to investigate the vegetation and habitat environment of Sageretia thea which is distributed in Jeju island, Korea. Sageretia thea were mainly distributed to the west area in Jeju island. Soil pH and EC of Sageretia thea habitat were 5.8 and $0.34dS{\cdot}m^{-1}$. The contents of organic matter, available phosphate, exchangeable potassium, exchangeable sodium, exchangeable magnesium and exchangeable calcium were 15.27%, $13.6mgkg^{-1}$, $0.27cmol_+kg^{-1}$, $1.3cmol_+kg^{-1}$, $1.7cmol_+kg^{-1}$, $4.9cmol_+kg^{-1}$, respectively. Thirty one taxa including 25 families, 31 genus, 27 species and 4 varieties were identified surrounding Sageretia thea habitat. Specific plant species were 1 taxon in III grade, 1 taxon in I grade and 3 taxa in I grade.

Development of Advanced Annunciator System for Nuclear Power Plants

  • Hong, Jin-Hyuk;Park, Seong-Soo;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.185-190
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    • 1995
  • Conventional alarm system has many difficulties in the operator's identifying the plant status during special situations such as design basis accidents. To solve the shortcomings, an on-line alarm annunciator system, called dynamic alarm console (DAC), was developed. In the DAC, a signal is generated as alarm by the use of an adaptive setpoint check strategy based on operating mode, and time delay technique is used not to generate nuisance alarms. After alarm generation, if activated alarm is a level precursor alarm or a consequencial alarm, it would be suppressed, and the residual alarms go through dynamic prioritization which provide the alarms with pertinent priorities to the current operating mode. Dynamic prioritization is achieved by going through the system- and mode-oriented prioritization. The DAC has the alarm hierarchical structure based on the physical and functional importance of alarms. Therefore the operator can perceive alarm impacts on the safety or performance of the plant with the alarm propagation from equipment level to plant functional level. In order to provide the operator with the most possible cause of the event and quick cognition of the plant status even without recognizing the individual alarms, reactor trip status tree (RTST) was developed. The DAC and the RTST have been simulated with on-line data obtained from the full-scope simulator for several abnormal cases. The results indicated that the system can provide the operator with useful and compact information fur the earlier termination and mitigation of an abnormal state.

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A Development of PC/Ethernet based Fieldbus Network for Large Realtime Data Communication

  • Gwak, Kwi-Yil;Lee, Sung-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.362-367
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    • 2005
  • Control network adopted in the national power-plant or manufactory are mostly vendor-dependent products, which have their own special specification, components and individual communication methods. These systems not only raise installation cost, but also bring many difficulties to maintenance and extension. To overcome these problems, this paper introduces a development and application case of a new "PC/Ethernet-based fieldbus" architecture and protocol to be used in mid-level fieldbus. The designed system has a basic idea of "3 Layers fieldbus over Standard-LAN" and implemented on PCs. PC gives user friendly environment. By using an open standard Ethernet in layer 1,2, the system has low cost, wide communication bandwidth and high compatibility. Layer 3 protocol designed for large realtime data communication makes user bypass TCP/IP layer and gives user direct access to the Ethernet. This new protocol eliminates potential collision of Ethernet, and transmits large periodic/non-periodic control data by using long-frame/wide-bandwidth of Ethernet effectively, and offers simple API-Services to the upper layer. Since the system have installed in H-power plant simulator and U-nuclear power plant simulator in Korea, it have been proved to be efficient and stable without any trouble in realtime communication service for full-scope plant simulator that has a lot of control elements.

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Plant Cultivation System Using the IoT (사물 인터넷을 이용한 식물재배시스템)

  • Lee, Gi-Young;Kim, Ho-Hyen;Jeong, Youn-Ha;No, Han-Hyul;Park, Yong-Wook
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.4
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    • pp.657-662
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    • 2017
  • For modern people who lack the time, the plants became more interested as they gave emotional stability and proved the purifying function of plants from harmful substances such as fine dust. In this study, we established a standard vegetation cultivation system that can easily grow indoors without any special knowledge, based on criteria such as temperature, soil humidity, and illumination. And we implemented a system that provides simple information needed for plant management by using Bluetooth function and provides contents that can get know-how necessary for plant management.

Competition Responses of Populus alba Clone ‘Bolleana’ to red:far-red light

  • Bae, Han-hong;Kang, Ho-duck;Richard B. Hall
    • Plant Resources
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    • v.7 no.1
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    • pp.77-86
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    • 2004
  • The reduced ratio of red:far-red (R:FR) light acts as a measure of the proximity of competitors and plants can detect the potentially competing neighbor plants by perceiving reflected R:FR signals and initiate the response of “shade avoidance” before actual shading occurs. The phytochrome system is responsible for monitoring the changes in the R:FR and initiating the shade avoidance response. The response to low R:FR ratio was studied in a white aspen Populus alba clone ‘Bolleana’ using two filter systems: a clear plastic filter system that allows a R:FR ratio less than 1.0 to pass from adjacent border plant reflection; and a special commercial plastic that blocks FR light and creates a R:FR ratio above 3.0. The reduced R:FR signals enhanced the stem elongation in response to competition at the expense of relative stem diameter growth. Trees grown inside clear chambers were 27 % taller than trees grown inside the FR-blocking filter chambers. Stem taper of clear chamber trees was 16% less than the FR-blocking filter trees. Low R:FR also induced 22% more stem dry weight and 13% greater petiole length per leaf compared to the FR-blocking filter trees. There were no statistically significant differences in leaf area, leaf number increment, and total dry weight between the two light filter treatments.

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Distribution of vascular plant in Mt. Cheonsung, Yangsan (양산 천성산지역 관속식물의 분포)

  • Shin, Hyun-Tak;Lee, Jae-Yoon
    • Korean Journal of Plant Resources
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    • v.22 no.2
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    • pp.180-194
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    • 2009
  • 588 taxa of vascular plants including 121 families, 399 genera, 510 species, 67 varieties, 2 subspecies, 7 forma, and 2 hybrid species were investigated in Mt. Cheonsung. Among them, 116 species were newly added in this research. The area for Gyeongbu High-speed Railway passes Mujechi 3, 4, 5, and 6 and Daeseongsa around the wetlands were investigated 6 species of rare and endangered plants, 9 species of endemic plants and 37 species of special flora plants in Mt. Cheonsung. Appear due to the construction of the Gyeongbu High-speed Railway vegetation changes, especially about the impact of wetland plants for long-term monitoring is expected to need. Moreover, plant preservation plan about water source change in upper wetland should be established.

A Study on the Formation and Reduction of NOx in 5TPD SRF Boiler (5톤/일 규모 SRF 전용 연소보일러에서의 질소산화물의 생성과 저감에 대한 연구)

  • Yoon, Young-Sik;Park, Dong-Kyu;Gu, Jae-Hoi;Park, Yeong-Su;Seo, Yong-Chil
    • Journal of Korea Society of Waste Management
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    • v.35 no.7
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    • pp.647-652
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    • 2018
  • The emission of nitrogen oxides has a great environmental impact. It leads to Los Angeles type smog, and it recently has attracted attention as a source of ultrafine dust. The main sources of nitrogen oxides are internal combustion engines and industrial boilers. These emission sources are processes that are essential for human industrial activities, so the regulation of original use is impossible. Therefore, special control methods should be applied to reduce NOx emissions into the atmosphere. In this study, we investigated how the supply of ER and urea influences the removal of nitrogen oxides from SRF combustion boilers. Experimental results show that the removal efficiency of nitrogen oxides can be up to 80% under the conditions of ER 2.0 and a urea feed of 0.5 LPM.

Seismic Performance of Alternative Steel Structural Systems for an Equipment-Supporting Plant Structure (플랜트 설비 지지용 대안 강구조 시스템의 내진성능)

  • Kwak, Byeong Hun;Ahn, Sook-Jin;Park, Ji-Hun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.27 no.1
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    • pp.13-24
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    • 2023
  • In this study, alternative seismic force-resisting systems for plant structure supporting equipment were designed, and the seismic performance thereof was compared using nonlinear dynamic analysis. One alternative seismic force-resisting system was designed per the requirement for ordinary moment-resisting and concentrically braced frames but with a reduced base shear. The other seismic force-resisting system was designed by accommodating seismic details of intermediate and unique moment-resisting frames and special concentrically braced frames. Different plastic hinge models were applied to ordinary and ductile systems based on the validation using existing test results. The control model obtained by code-based flexible design and/or reduction of base shear did not satisfy the seismic performance objectives, but the alternative structural system did by strengthened panel zones and a reduced effective buckling length. The seismic force to equipment calculated from the nonlinear dynamic analysis was significantly lower than the equivalent static force of KDS 41 17 00. The comparison of design alternatives showed that the seismic performance required for a plant structure could be secured economically by using performance-based design and alternative seismic-force resisting systems adopting minimally modified seismic details.

History of the Korean Society of Applied Entomology for its First Fifty Years (한국응용곤충학회의 첫 50년 역사)

  • Boo, Kyung-Saeng
    • Korean journal of applied entomology
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    • v.51 no.2
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    • pp.171-190
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    • 2012
  • The Korean Society of Applied Entomology (KSAE) celebrates its First 50 years history this year, 2011. It began in the year 1962, as the Korean Society of Plant Protection (KSPP) to discuss all aspects of plant protection including entomology and plant pathology. At that time it was one of the earliest scientific ones among agricultural societies in Korea. Before liberation from the Japanese colonial rule there were a few scientific societies for Japanese scientists only in the Korean Peninsula. It seemed that there was a single exception, in medical field, formed by and operated for Korean ethnics. Right after the liberation, Korean scientists rushed to form new scientific societies in the fields of mechanical engineering, architecture, textile, internal medicine, biology, etc. in 1945, mathematics, chemistry, metallurgy, etc. in 1946, and so on. But agricultural scientists had to wait for more time before setting up their own scientific society, Korean Agricultural Society(韓國農學會), comprising all agricultural subfields, in 1954. They had annual meetings and published their own journal every year until 1962. Then those working in the plant protection field established their own KSPP, right after their section meeting in 1962. At that time the total number of participants for KSPP were only around 50. KSPP scientists were interested in plant pathology, agricultural chemicals, weed science, or bioclimate, besides entomology. They had annual meetings once or twice a year until 1987 and published their own journal, Korean Journal of Plant Protection (KJPP), once a year at the earlier years but soon gradually increasing the frequency to four times a year later. Articles on entomology and plant pathology occupied about 40% each, but the number of oral or posters were a little bit higher on plant pathology than entomology, with the rest on nematology, agricultural chemicals, or soil microarthropods. There also had a number of symposia and special lectures. The presidentship lasted for two years and most of president served only one term, except for the first two. The current president should be $28^{th}$. In the year 1988, KSPP had to be transformed into the applied entomology society, Korean Society of Applied Entomology (KSAE), because most of plant pathologists participating left the society to set up their own one, Korean Society of Plant Pathology in 1984. Since that time the Society concentrates on entomology, basic and applied, with some notes on nematology, acarology, soil microarthropods, agricultural chemicals, etc. The Society has been hosting annual meetings at least twice a year with special lectures and symposia, from time to time, on various topics. It also hosted international symposia including binational scientific meetings twice with two different Japanese (applied entomology in 2003 and acarology in 2009) societies and the Asia-Pacific Congress of Entomology in 2005. The regular society meeting of this year, 2011, turns out to be the 43rd and this autumn non-regular meeting would be the 42nd. It has been publishing two different scientific journals, Korean Journal of Applied Entomology (KJAE) since 1988 and the Journal of Asia-Pacific Entomology (JAPE) since 1998. Both journals are published 4 times a year, with articles written in Korean or English in the first, but those in English only in the latter with cooperation from the Taiwan Entomological Society and the Malaysian Plant Protection Society since 2008. It is now enlisted as one of those SCI(science citation index) extended. The highest number of topics discussed at their annual meetings was on ecology, behavior, and host resistance. But at the annual meetings jointly with the Korean Society of Entomology, members were more interested in basic aspects, instead of applied aspects, such as physiology and molecular biology fields. Among those societies related to entomology and plant protection, plant pathology, pesticide, and applied entomology societies are almost similar in membership, but entomology and plant pathology societies are publishing more number of articles than any others. The Society is running beautifully, but there are a few points to be made for further improvement. First, the articles or posters should be correctly categorized on the journals or proceedings. It may be a good idea to ask members to give their own version of correct category for their submissions, either oral or poster or written publication. The category should be classified detailed as much as possible (one kind of example would be systematics, morphology, evolution, ecology, behavior, host preference or resistance, physiology, anatomy, chemical ecology, molecular biology, pathology, chemical control, insecticides, insecticide resistance, biocontrol, biorational control, natural enemies, agricultural pest, forest pest, medical pest, etc.) and such scheme should be given to members beforehand. The members should give one or two, first and second, choices when submitting, if they want. Then the categories might be combined or grouped during editing for optimal arrangement for journals or proceedings. Secondly the journals should carry complete content of the particular year and author index at the last issue of that year. I would also like to have other information, such as awards and awardees in handy way. I could not find any document for listing awards. Such information or article categorization may be assigned to one of the vice presidents. I would rather strongly recommend that the society should give more time and energy on archive management to keep better and more correct history records.