• Title/Summary/Keyword: control suitability

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Suitability Site Selection by Meteorological Factors for the Protected Horticulture Complex in Saemanguem (기상환경 분석을 통한 새만금 시설원예단지 적지분석 연구)

  • Kang, Dong Hyeon;Lee, Si Young;Kim, Jong Koo;Choi, Hong Ki;Park, Min Jung;Yun, Sung-Wook;Son, Jin Kwan
    • Journal of Bio-Environment Control
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    • v.25 no.1
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    • pp.1-8
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    • 2016
  • This study was conducted to find the suitability site for the construction of Saemangeum horticulture complex taking into account cost-effective environmental management by analyzing and comparing meteorological conditions. By overlapping the thematic maps, we extracted the regions that scored 50-59 points as suitable sites for the development project. Of these pre-selected sites, we selected the final candidate region for the protected horticulture by overlapping the sites selected for agricultural and living environment construction. The results of this study will contribute to generating added values by minimizing the environmental management costs for horticulture and landscaping. The operation of a large-scale protected horticulture and landscaping in the Saemangeum Complex will enhance the agricultural competitiveness of our country in the global market.

Study on Emission Control for Precursors Causing Acid Rain (VI) : Suitability of Aquatic Plant Biomass as a Co-combustion Material with Coal

  • Hauazawa, Atsushi;Gao, Shidong;Sakamoto, Kazuhiko
    • Asian Journal of Atmospheric Environment
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    • v.2 no.2
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    • pp.102-108
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    • 2008
  • In China, energy and environmental problems are becoming serious owing to rapid economic development. Coal is the most problematic energy source because it causes indoor and outdoor air pollution, acid rain, and global warming. One type of clean coal technology that has been developed is the coal-biomass briquette (or bio-briquette, BB) technique. BBs, which are produced from pulverized coal, biomass (typically, agricultural waste), and a sulfur fixation agent (slaked lime, $Ca(OH)_2$) under high pressure without any binder, have a high sulfur-fixation effect. In addition, BB combustion ash, that is, the waste material, can be used as a neutralization agent for acidic soil because of its high alkalinity, which originates from the added slaked lime. In this study, we evaluated the suitability of alternative biomass sources, namely, aquatic plants, as a BB constituent from the perspective of their use as a source of energy. We selected three types of aquatic plants for use in BB preparation and compared the fuel, handling, and environmental characteristics of the new BBs with those of conventional BBs. Our results showed that air-dried aquatic plants had a higher calorific value, which was in proportion to their carbon content, than agricultural waste biomass; the compressive strength of the new BBs, which depends on the lignin content of the biomass, was high enough to bear long-range intracontinental transport in China; and the new BBs had the same emission control capacity as the conventional BBs.

Basic reproduction number of African swine fever in wild boars (Sus scrofa) and its spatiotemporal heterogeneity in South Korea

  • Lim, Jun-Sik;Kim, Eutteum;Ryu, Pan-Dong;Pak, Son-Il
    • Journal of Veterinary Science
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    • v.22 no.5
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    • pp.71.1-71.12
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    • 2021
  • Background: African swine fever (ASF) is a hemorrhagic fever occurring in wild boars (Sus scrofa) and domestic pigs. The epidemic situation of ASF in South Korean wild boars has increased the risk of ASF in domestic pig farms. Although basic reproduction number (R0) can be applied for control policies, it is challenging to estimate the R0 for ASF in wild boars due to surveillance bias, lack of wild boar population data, and the effect of ASF-positive wild boar carcass on disease dynamics. Objectives: This study was undertaken to estimate the R0 of ASF in wild boars in South Korea, and subsequently analyze the spatiotemporal heterogeneity. Methods: We detected the local transmission clusters using the spatiotemporal clustering algorithm, which was modified to incorporate the effect of ASF-positive wild boar carcass. With the assumption of exponential growth, R0 was estimated for each cluster. The temporal change of the estimates and its association with the habitat suitability of wild boar were analyzed. Results: Totally, 22 local transmission clusters were detected, showing seasonal patterns occurring in winter and spring. Mean value of R0 of each cluster was 1.54. The estimates showed a temporal increasing trend and positive association with habitat suitability of wild boar. Conclusions: The disease dynamics among wild boars seems to have worsened over time. Thus, in areas with a high elevation and suitable for wild boars, practical methods need to be contrived to ratify the control policies for wild boars.

Effect of Initial (Reference) Welding Current for Adaptive Control and It's Optimization to Secure Proper Weld Properties in Resistance Spot Welding

  • Ashadudzzaman, Md.;Choi, Il-Dong;Kim, Jae-Won;Nam, Dae-Geun;Park, Yeong-Do
    • Journal of Welding and Joining
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    • v.33 no.6
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    • pp.13-20
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    • 2015
  • Many automotive companies are endeavoring to improve the quality of resistance spot welding by updating body-in-white (BIW) production line with adaptive control spot welding system to compensate the process disturbances such as gap, electrode wear, oxidized surfaces, poor fit up and adhesive etc. Most of the commercial adaptive weld controllers require proper "Initial Welding Schedule" or "Reference weld" to achieve compensation in welding parameters during real time welding. In this study, the compensation of a commercial adaptive weld controller had been observed and analyzed thoroughly for various process disturbances to find optimal initial welding schedule. It was observed that 90 percent of the expulsion current in constant current control as reference welding schedule conferred the maximum button diameter in adaptive control welding. Finally, effects of each disturbance in combined field disturbances system with adaptive control had also been confirmed with the design of experiment (DOE) by minitab(R)16 for combined disturbances situation and suitability of optimum initial weld current had also established with real body part validation test.

Effects of Potato on the Storage of Kimchi (배추김치의 저장성에 미치는 감자 첨가의 영향)

  • Paik, Jae-Eun
    • The Korean Journal of Food And Nutrition
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    • v.20 no.4
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    • pp.421-426
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    • 2007
  • This study was carried out to investigate the properties of Kimchi made with potato as compared to Kimchi made with radish. The pH, acidity, hardness, and number of lactic acid bacteria were examined as properties of the Kimchi to determine the suitability of adding the potato and with focus on the possible duration of storage. First in the case of pH, the storage duration at pH $4.2{\sim}4.3$, which is the state for optimal tasting Kimchi, was approximately 10days in the control group, while that of the experimental group was 10 to 16 days, and thus, longer than the control. Second in the case of acidity, representing the maturity of Kimchi, we examined the time it took to reach 0.6% acidity, in which the experimental group took more longer time than the control. Although the experimental group was slower to mature than the control, the period for keeping at the proper pH was longer than that of the control group. Thirdly, in the case of hardness, which relates to softening, the experimental group had remarkably high values. This suggests that the Kimchi in the experimental group had a more rigid texture and more difficultly softening than the control group. Lastly in the case of the number of lactic acid bacteria, which closely relates to the process of fermentation, there were no significant differences. In conclusion, these results indicate that adding potato to Kimchi can extend its storage period.

A New Performance Function-Based Control Strategy for Hybrid Series Active Power Filter in Three-Phase Four-Wire Systems (3상 4선식 하이브리드 형 직렬 능동전력필터에 대한 새로운 성능함수 제어 이론)

  • 신재화;김진선;김영석
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.52 no.11
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    • pp.563-571
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    • 2003
  • In this paper, the control algorithm and control method for a combined system of shunt passive filter and series active filter in 3-phase 4-wire system are discussed. Moreover, the three-phase four-wire system is widely employed in distributing electric energy to several office building and manufacturing plants. In such systems, the third harmonic and its 3th harmonics are termed as triple and zero sequence components that do not cancel each other in the system neutral. Consequently, the triple harmonics add together creating a primary source of excessive neutral current. Regarding this concern, this paper presents a new control algorithm for a series hybrid active system, whereas the control approach it adopts may directly influence its compensation characteristics. Hence, the advantage of this control algorithm is direct extraction of compensation voltage reference and the required rating of the series active filter is much smaller than that of a conventional shunt active filter. Some experiments were executed and experimental results from a prototype active power filter confirm the suitability of the proposed approach.

Development of K-Maryblyt for Fire Blight Control in Apple and Pear Trees in Korea

  • Mun-Il Ahn;Hyeon-Ji Yang;Sung-Chul Yun
    • The Plant Pathology Journal
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    • v.40 no.3
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    • pp.290-298
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    • 2024
  • K-Maryblyt has been developed for the effective control of secondary fire blight infections on blossoms and the elimination of primary inoculum sources from cankers and newly emerged shoots early in the season for both apple and pear trees. This model facilitates the precise determination of the blossom infection timing and identification of primary inoculum sources, akin to Maryblyt, predicting flower infections and the appearance of symptoms on various plant parts, including cankers, blossoms, and shoots. Nevertheless, K-Maryblyt has undergone significant improvements: Integration of Phenology Models for both apple and pear trees, Adoption of observed or predicted hourly temperatures for Epiphytic Infection Potential (EIP) calculation, incorporation of adjusted equations resulting in reduced mean error with 10.08 degree-hours (DH) for apple and 9.28 DH for pear, introduction of a relative humidity variable for pear EIP calculation, and adaptation of modified degree-day calculation methods for expected symptoms. Since the transition to a model-based control policy in 2022, the system has disseminated 158,440 messages related to blossom control and symptom prediction to farmers and professional managers in its inaugural year. Furthermore, the system has been refined to include control messages that account for the mechanism of action of pesticides distributed to farmers in specific counties, considering flower opening conditions and weather suitability for spraying. Operating as a pivotal module within the Fire Blight Forecasting Information System (FBcastS), K-Maryblyt plays a crucial role in providing essential fire blight information to farmers, professional managers, and policymakers.

Implementation of Broadband LED Lighting System Using ZDMX Modules Based DMX512 Protocol (DMX512 프로토콜 기반의 ZDMX 모듈을 이용한 광대역 LED 조명 시스템 구현)

  • Kim, Jae-In;Hwang, Bu-Hyun
    • The Journal of the Korea Contents Association
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    • v.10 no.11
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    • pp.38-47
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    • 2010
  • DMX512 protocol controls a lighting system for outdoor lightings and stage lightings. But lighting systems using DMX512 protocol based wired needs expensive cost in installation, maintain, repair. And it has restrictions about control channel numbers and its ranges. Also, it needs additional equipments for the control of lighting systems which installed on wide area. In this paper, we propose wireless control technique and a ZDMX module for lighting systems on wide area based on DMX512 protocol. Our technique solves problems of DMX512 protocol, and it can control lighting systems on wide area effectively. We developments the LED lighting system using ZDMX modules and we have confirmed the suitability of our technique for real environment.

Development of Onshore Offshore Tower Elevator with load distribution endless winder and integrated control panel (하중 분산형 엔드리스 와인더와 통합형 제어반을 적용한 육상 해상 풍력타워 승강기 개발)

  • Lee, Sang-Hun
    • Journal of the Korean Society of Industry Convergence
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    • v.22 no.6
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    • pp.711-719
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    • 2019
  • At present, wind power is the fastest growing technology in the world. The domestic market depends heavily on imports for wind tower lift. so it manage through the overseas maker. The lift manufacture, establishment and maintenance utility is increasing, localization development of one wind tower lift is necessary with domestic fundamental base technique. In this paper, we will study the components necessary for the development of onshore offshore wind tower elevators, which are currently dependent on total imports, in line with the high growth of the wind market and the enlargement of the wind power generators. First of all, endless winders and cabins, which are the core components of the offshore wind tower lift, were examined for the components that affect the structural safety. Structural analysis was performed on Sheave, which is responsible for most of the lift lifting loads, and Block Stop, a safety device that prevents the cabin from falling in an emergency. The structural suitability was evaluated by comparing with the safety factor. In addition, the on-board control panel combines the control panel of the elevator and the drive motor driving the endless winder for efficient control of the offshore wind tower lift. The addition of features improves ride comfort at departure.

Developing a Pressure Control Valve for Air Extraction Cupping Device (부항 장치용 압력 제어 밸브 개발)

  • Lee, Jae Yong;Shim, Dong Wook;An, Soo Kwang;Kim, Eun Seok;Lee, Byung Ryul;Yang, Gi Young
    • Korean Journal of Acupuncture
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    • v.38 no.4
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    • pp.308-316
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    • 2021
  • Objectives : This study aimed to develop a cupping pressure control valve for limiting maximum negative pressure while achieving clinical therapeutic outcomes to minimize side effects induced by excessive negative pressure of air extraction cupping devices. Methods : To determine the clinical necessity and suitability of the cupping pressure control valve, this study was designed to measure the change in pressure with or without the valve using both a manual and an electric suction pump. Results : While the maximum pressure was limited by the pressure control valve, the pressure did not increase above a certain level regardless of the type of manual or electric pump. Conclusions : This study will contribute to the development of a safer and more effective base technology for cupping treatment in oriental medicine.