• Title/Summary/Keyword: low-order control

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Physiological Responses for Soil Water Stresses in 'Mihong' Peach Tree (복숭아 '미홍'의 토양 수분 스트레스에 따른 생리반응)

  • Kwon, Yong Hee;Lee, Jae Man;Han, Hyun Hee;Ryu, Suhyun;Jeong, Jae Hoon;Do, Gyung-Ran;Han, Jeom Hwa;Lee, Han-Chan;Park, Hee-Seung
    • Journal of Bio-Environment Control
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    • v.25 no.4
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    • pp.255-261
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    • 2016
  • The present study was conducted to characterize physiological responses of aerial part according to soil water stresses in 'Mihong' peach trees. Discolorations, wilting and falling of leaves were observed in chronological order as response for waterlogging and no irrigation and the phenomena started from basal to end of shoots. Shoot growth in elongation and thickness decreased and fallen leaves were severe in waterlogged trees. Function of water uptake by roots and photosynthesis and leaf respiration decreased by waterlogging. Leaf chlorophyll contents decreased in both treatments. In waterlogging treatment, decrease of chlorophyll was observed in normal leaves with waterlogging using light microscopy. Starch content was lower in both treatment and carbohydrate content was lower in root with waterlogging. These results demonstrated that waterlogging weakened the function of soil water uptake and movement and decreased photosynthesis and fallen leaves. Finally the peach trees would wither or suffer low temperature damage through the shortage of reserve accumulations. We suggested that waterlogging damage in peach trees could be reduced to take notice of irrigation and install drainage facility to improve soil condition.

Performance Evaluation of the MAC Protocols for WDM Metro Ring with Wavelength-Shared Nodes Connecting Broadband Access Networks (대역 액세스 망을 연결하는 파장 공유 노드 기반 WDM 메트로 링의 MAC 프로토콜 성능 평가)

  • So Won-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.1 s.343
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    • pp.111-120
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    • 2006
  • In this paper, a node architecture of WDM metro network for connecting broadband access networks to converge wire/wireless networks. In consideration of the proposed node architecture and network requirements we proposed and evaluated medium access control protocols. We review WDM related technologies of sub-carrier multiplexing and optical components in order to resolve the bottleneck between optical backbone networks md access networks, and a access node architecture sharing common wavelength is introduced. Source-stripping (SS) MAC protocol Is evaluated under the proposed functional node architecture. DS+IS (Destination-Stripping and Source-Stripping) and DS+IS (Destination-Stripping and Intermediate-Stripping) MAC protocols are described to increase the slot-reuse factor which is low on SS MAC protocol. The key function of new MAC protocols regards the optical switch module of proposed node architecture and helps intermediate or source access nodes for dropping slots to destinations of different wavelength group. Thus, slot-reuse factor increases as the MAC protocols reduce the unnecessary ring-rotation of transferred slots. We use a numerical analysis to expect bandwidth efficiency and maximum throughput by slot-reuse factor Throughput network simulation, the verification of throughput, queuing delay, and transmission fairness are compared among MAC protocols.

An Analysis on the Educational Needs for the Smart Farm: Focusing on SMEs in Jeon-nam Area (중소·중견기업의 스마트팜 교육 수요 분석: 전남지역을 중심으로)

  • Hwang, Doo-hee;Park, Geum-Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.649-655
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    • 2020
  • This study determined effective educational strategies by investigating and analyzing the related educational demands for SMEs (small and medium-sized enterprises) in the 4th Industrial Revolution based area of smart farms. In order to derive the approprate educational strategies, Importance-Performance Analysis (IPA) and Borich's Needs Assessment Model were conducted based on the smart farm technological field. As a result, the education demand survey showed high demand for production systems and intelligent farm machinery. In detail, Borich's analysis showed the need for pest prevention and diagnosis technology (8.03), network and analysis SW linkage technology (7.83), and intelligent farm worker-agricultural power system-electric energy hybrid technology (7.43). In contrast, smart plant factories (4.09), lighting technology for growth control (4.46) and structure construction technology (4.62) showed low demands. Based on this, the IPA portfolio shows that the network and analysis SW linkage technology and the CAN-based complex center are urgently needed. However, the technology that has already been developed, such as smart factory platform development, growth control lighting technology and structure construction technology, was oversized. Based on these results, it is possible to strategically suggest the customized training programs for industrial sectors of SMEs that reflect the needs for efficiently operating smart farms. This study also provides effective ways to operate the relevant training programs.

Buffer Capacity of So Horizon Soils of Andisols from Jeju Island: Solubility Effect of Mineral Phases (제주도 Andisols Bo층 토양의 산성화에 대한 완충능력: 광물상 용해도 특성의 영향)

  • 이규호;송윤구;문지원;문희수
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.2
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    • pp.114-121
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    • 2002
  • Buffer capacities for two Bo horizon soils or Andisols developed from different parent materials have been investigated. The titration curves from column leaching experiment show that buffering occurred at pH 4.0 and 6.0. The buffer intensity or soil developed from pyroclastic materials (P-soil) is higher than that from basalts (B-soil). From batch test we have found that proto-imogolite and/or imogolite may control Al solubility as well as $Al(OH) _3$in the moderate acid condition. The buffer intensities ($\beta$) of P-soils were plotted on the theoretical buffering curve of $Al(OH)_3$, while $\beta$ of B-soils approached to that of proto-imogolite, which shows the solubility of short-range-order materials in P-soil control the buffer capacity. Buffering at pH 6.0 is thought to be the result of dissolution of some silicate clays and exchange reactions between $H^{+ }$and base-forming cations. Considering the amount of annual acid precipitation, aluminum solubility of Andisols, and the low BS (Base Saturation percentage), it can be predicted that prolonged acid precipitation will reduce the buffer capacity of soils and lead to soil acidification.

Use of Sprinkler System for Production Forest Management of Pine Mushroom (Tricholoma matsutake) (살수장치(撒水裝置)를 이용(利用)한 송이산 관리(管理)에 관(關)한 연구(硏究))

  • Chung, Sang Bae;Kim, Chul Su
    • Journal of Korean Society of Forest Science
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    • v.94 no.1 s.158
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    • pp.21-25
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    • 2005
  • In order to prevent the pine mushrooms, Tricholoma matsutake, from being damaged by the pine needle gall midges, Thecodiplosis japonensis, and thereby, to increase their production and improve their quality, a sprinkler system was installed on the mushroom field. A low-concentration insecticide (deltamethrin 1% EC, x2,000) was sprayed once at insects' most active time every day during the period of insects' adult occurrence and thereafter, the irrigation by ground water spraying was periodically enforced. Such a test was conducted at Yangyang-Gun, Kwangwon-do, Korea for 2 years from 2000 through 2001. The pine needle gall midges generally emerged for about 40 days from late May to early July. 50% emergence of them was about June 6, and peak emergence (more than 80%) was early or mid-June. Gall formation rate was 3.5% on average with this ground insecticide spraying, while 51.3% when not treated. Control effectiveness of this insecticide spraying was 92.3%, which was higher than 82.5% by the conventional injection of insecticide into tree stems. Pine mushrooms emerged for about 35 days from mid-September through earlier October, and around 80% of them did for about 15 days from late September through early October. As a result of the periodic ground water-spraying (30 mm per week) for 2 months (from August to October), the production of mushrooms increased by 74.3% (110% in terms of weight), with their quality improvement. The mushrooms produced from the treated stand by the spraying system were priced 8,670,000 wons per hectare, and thus, the net income deducting the facility and management cost was 4,310,000 wons, about 5% higher than value from the control stand. It was analyzed that this treatment was significantly cost effective when the facilities are used more than 5 years.

Effect of Essential Amino Acid Deficient Diets in Feeding Response and c-fos Expression in Rats Brain in Response to Methionine Deficiency (필수아미노산 결핍에 의한 섭식반응과 Methionine 결핍이 흰쥐의 뇌내 c-fos 발현에 미치는 영향)

  • Kim, C.H.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.727-738
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    • 2002
  • This study was conducted to investigate the effect of essential amino acid(EAA) deficient diets on short-term feeding response and the Fos expression in brain area when methionine deficiency diet fed, and thereby to know the mechanism of feed intake regulation. In all trials, experimental diets were formulated with pure amino acid mixture to level of 15% nitrogen. Rats were adapted to a 6-hr single-meal feeding per day(17:00${\sim}$21:00). Feed intake and body weight were monitored every hour after 7-day of feeding of individual EAA deficient diets in Exp. Ⅰ. In Exp. Ⅱ, Fos immuno- histochemistry was determined in various regions of brain to identify the regions that is related to suppressed feed intake following feeding methionine-deficient diet. Fos expression was examined to know the initial sensitive region in the brains of rats at 3h after feeding of the control and methionine deficient diet(-Met). Initial response to EAA deficiency diets was severely depressed in methionine deficiency diet, but the depression was low in threonine deficiency diet. However, the feed intake at 3rd day in rats was depressed in the order of His(71%), Leu(68%), Ile(66%), Thr(63%), Trp(61%), Val(55%), Phe(52%), Met(51%), Lys(44%) and Arg(24%). Fos immunoreaction in neural regions(PPC, amygdala and EPC) of pyrifrom cortex was increased in the -Met group more than in the control diet group, but those in LH, VMH and PVM were similar. Thus, based on these data, the PPC was identified as the initial response area in the -EAA diet.

Fabrication and Characteristics of a Varactor Diode for UHF TV Tuner Operated within Low Tuning Voltage (저전압 UHF TV 튜너용 바렉터 다이오드의 제작 및 특성)

  • Kim, Hyun-Sik;Moon, Young-Soon;Son, Won-Ho;Choi, Sie-Young
    • Journal of Sensor Science and Technology
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    • v.23 no.3
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    • pp.185-191
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    • 2014
  • The width of depletion region in a varactor diode can be modulated by varying a reverse bias voltage. Thus, the preferred characteristics of depletion capacitance can obtained by the change in the width of depletion region so that it can select only the desirable frequencies. In this paper, the TV tuner varactor diode fabricated by hyper-abrupt profile control technique is presented. This diode can be operated within 3.3 V of driving voltage with capability of UHF band tuning. To form the hyperabrupt profile, firstly, p+ high concentration shallow junction with $0.2{\mu}m$ of junction depth and $1E+20ions/cm^3$ of surface concentration was formed using $BF_2$ implantation source. Simulation results optimized important factors such as epitaxial thickness and dose quality, diffusion time of n+ layer. To form steep hyper-abrupt profile, Formed n+ profile implanted the $PH_3$ source at Si(100) n-type epitaxial layer that has resistivity of $1.4{\Omega}cm$ and thickness of $2.4{\mu}m$ using p+ high concentration Shallow junction. Aluminum containing to 1% of Si was used as a electrode metal. Area of electrode was $30,200{\mu}m^2$. The C-V and Q-V electric characteristics were investigated by using impedance Analyzer (HP4291B). By controlling of concentration profile by n+ dosage at p+ high concentration shallow junction, the device with maximum $L_F$ at -1.5 V and 21.5~3.47 pF at 0.3~3.3 V was fabricated. We got the appropriate device in driving voltage 3.3 V having hyper-abrupt junction that profile order (m factor) is about -3/2. The deviation of capacitance by hyper-abrupt junction with C0.3 V of initial capacitance is due to the deviation of thermal process, ion implantation and diffusion. The deviation of initial capacitance at 0.3 V can be reduced by control of thermal process tolerance using RTP on wafer.

Effects of Emotional Labor on Customer Orientation by Service Career of Security Agents (시큐리티 요원의 근무경력에 따른 감정노동이 고객지향성에 미치는 영향)

  • Kim, Eui-Young;Lee, Jun-Woo;Cho, Sung-Jin
    • Korean Security Journal
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    • no.37
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    • pp.269-293
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    • 2013
  • Raising the level of quality of the security industry is an urgent matter. Since security service is provided through direct contact with customers, the security agents' expression of emotion directly influences the evaluation of the security company or their own earnings. So emotion control at customers demand is necessary above all things, and this research established what difference the service career makes in the influence that the security agent's emotional labor exerts on customer orientation, and the results of the analysis are summarized as follows. First, the security agent's emotional labor exerted negative effects on customer orientation. From this, the conclusion that the higher the security agent's emotional labor, the lower the customer orientation, was obtained. Second, the service career showed differences in the effects of the security agent's emotional labor on the customer orientation. In other words, the conclusion that the lower the security agent's service career, the greater effects the emotional labor exerts on the customer orientation, was obtained. In conclusion, in order to raise the level of customer service, systematic education to control the emotional labor of the security agents with low service career is necessary. Particularly, since the emotional labor of new employees is related to the service environment, the improvement of the service environment of the security agents is more important than anything else.

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Triazine Herbicide Treatment and Survival Rate of Pearl Millet Seedlings (Triazine 제초제(除草劑) 처리(處理)와 진주(眞珠)조의 생존율(生存率))

  • Choi, B.H.;Park, K.Y.
    • Korean Journal of Weed Science
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    • v.10 no.2
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    • pp.99-102
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    • 1990
  • Pearl millet (Pennisetum americanum (L.) Leeke) has been found as a promising new forage crop of higher quality and yield in Korea since 1985. The objective of the study was to select preemergence herbicides for weed control in growing pearl millet in order to reduce production cost and with increased yields. Propazine (Milogard 4L) was the best in controlling weeds without its phytotoxicity at the standard application rate, and with the highest survival rate of seedlings of peal millet "Suwon 1" hybrid. Sprayings with Atrazine and Simazine caused lower survival rate of peal millet and with their light phytotoxicity as compared with manual weeding and Propazine spraying. Alachlor killed pearl millet seedlings almost completely. Pendimethalin also was not good for weed control of peal millet due to its severe phytotoxicity and with very low survival rate of pearl millet seedlings.

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The Actual State and Improvement Proposal for Shading Structures in Korean Ginseng Fields (인삼재배시설의 실태 및 개선방안)

  • Nam, Sang-Woon
    • Journal of Bio-Environment Control
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    • v.12 no.3
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    • pp.114-120
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    • 2003
  • In order to provide fundamental data for development of controlled environment facilities in Korean ginseng (Panax ginseng C.A. Meyer) cultivation, field survey and analysis of structural and environmental engineering characteristics on the shading structures in ginseng fields (the ginseng houses) were carried out. In this study shading structures for ginseng cultivation were classified according to their structural materials, connection types, and detailed structures. That is they were classified into wood or steel frames, single or multi spans, and frame or cable types. As a result of the investigation, standardization of structural materials, fabrication and construction methods arc required. And it was considered that a reinforced design and a countermeasure for heavy snow are the most important matters for structural improvement. In parts of the environmental management, researches for setting up the irrigation standard are required in the first place. And it was investigated that an installation of the shading structures is a work being the most hard, taking a lot of time, and having need for automation. So controlled environment ginseng houses, with a low cost, a structural safety and a satisfactory workability, should be developed.