• Title/Summary/Keyword: C-UAS

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A Study n the Simulation-based Design Approach for Pneumatic Control System with Anti-leakage (시뮬레이션을 기초로한 누기보상 공압제어밸브시스템의 Design Approach에 관한 연구)

  • 김태형;정원지;최은재
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.488-491
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    • 1997
  • In this paper, a ncw control 'ialvc which can misc air-iraksge pneumatically and compensate pressure drop for an alrho~ st system uas proposed A new control valve called "Pneuniatic C70ntro1 Valve (PCV)" functions as a control valve to compcns;ltc prcssure in thc casc of air-leakage. by using the pure pneummatic control ofpilot pressure. Based on the sirnulation of the proposed PCY, thc experimental system was fabricaied su as to illustrate the efficient pcrformance of the proposed PCV with anti-leakage. Such good perfo~manccs of PCV in the air-hoist system are shown by the simulation. In addition, the simulation bascd design approach presented in this paper can be applied to any hydraulic or pneumatic-hydraulic system.

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Comparative Calorimetric Evaluation of Ammoniated Straw-Based Rations Supplemented with Low Levels of Untreated and Formaldehyde Treated Groundnut Cake and Fish Meal with Respect to Growing Buffalo Calves

  • Tiwari, C.M.;Jadhao, S.B.;Chandramoni, Chandramoni;Murarilal, Murarilal;Khan, M.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.6
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    • pp.761-773
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    • 2000
  • Eighteen growing male Murrah buffalo (Bubalus bubalis) calves were divided into three groups consisting of six animals each and fed three urea ammoniated wheat straw (UAS) -based rations supplemented with concentrate mixtures (roughage: concentrate ratio 58:42) containing deoiled ground nut cake, GNC (8%), formaldehyde treated GNC (8%) or fish meal (8%) to undertake comparative evaluation of these rations in terms of their $CH_4$ production and growth (285 d duration) potential. A digestibility trial (10 d duration) was followed by a comparative calorimetric study in respiration chamber. Dry matter (DM) intake (84.3 to $89.3g/kg\;W^{0.75}d^{-1}$) did not differ between treatments. The digestibility coefficient of DM, organic matter (OM), crude protein (CP), neutral and acid detergent fiber did not differ significantly in different diets. Urinary energy loss as a percent of gross energy (GE) was not affected by diets. Average values of $CH_4$ production were 84.3, 77.6 and 99.1 g/d and $CH_4$ energy losses as percent of gross energy were 5.7, 5.2 and 6.1 percent on .GNC, formaldehyde treated GNC and fishmeal, respectively, and did not differ significantly. When expressed per unit of digestible OM intake, $CH_4$ production (g) was lower (p<0.05) on formaldehyde treated GNC (30.6) than on untreated GNC (30.6) and fish meal (31.9). Total ME intake and heat production were similar and hence the energy balances on different diets were similar. Nutritive value of rations in terms of digestible CP and ME were similar. Average daily gain calculated on the basis of regression of fortnights on cumulative liveweight gain in calves fed on concentrate containing unprotected GNC, protected GNC and fish meal were 437.1, 483.9 and 481.6 g, respectively. This indicated that the intake of energy was sufficient to meet the requirement of calves growing at 400 g per d. However, CP intake was around 150% of the stipulated standard (Kearl, 1982). Feed conversion ratios on unprotected GNC, protected GNC and fish meal were 11.60, 11.10 and 10.4 respectively. It was concluded that because significantly (p<0.05) low $CH_4$ is produced on protected GNC (8%), it is very good and sustainable protein source in comparison to poor quality fish meal and untreated GNC to be used in concentrate mixture for supplementing UAS-based diets.

Altering undigested neutral detergent fiber through additives applied in corn, whole barley crop, and alfalfa silages, and its effect on performance of lactating Holstein dairy cows

  • Hosseini, Seyed Mohsen;Mesgaran, Mohsen Danesh;Vakili, Ali Reza;Naserian, Abbas Ali;Khafipour, Ehsan
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.3
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    • pp.375-386
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    • 2019
  • Objective: We hypothesized that silage additives may alter the undigested neutral detergent fiber (uNDF) content through ensiling. Therefore, urea and formic acid were applied to corn, whole barley crop (WBC) and alfalfa to change uNDF content of the ensiled forages. Methods: Six experimental diets at two groups of high uNDF (untreated corn and alfalfa silages [CSAS] and untreated whole barley and alfalfa silages [BSAS]) and low uNDF (urea-treated corn silage+untreated alfalfa silage [$CS_UAS$], urea-treated whole barley silage+untreated alfalfa silage [$BS_UAS$], untreated corn silage+formic acid-treated alfalfa silage [$CSAS_F$], and untreated whole barley silage+formic acid-treated alfalfa silage [$BSAS_F$]), were allocated to thirty-six multiparous lactating Holstein dairy cows. Results: The untreated silages were higher in uNDF than additive treated silages, but the uNDF concentrations among silages were variable (corn silage0.05). Milk yield tended to increase in the cows fed high uNDF diets than those fed low uNDF (p = 0.10). The cows fed diet based on urea-treated corn silage had higher milk yield than those fed other silages (p = 0.05). The substitution of corn silage with the WBC silage tended to decrease milk production (p = 0.07). Changing the physical source of NDF supply and the uNDF content from the corn silage to the WBC silage caused a significant increase in ruminal $NH_3-N$ concentration, milk urea-N and fat yield (p<0.05). The cows fed diets based on WBC silage experienced greater rumination time than the cows fed corn silage (p<0.05). Conclusion: Administering additives to silages to reduce uNDF may improve the performance of Holstein dairy cows.

A Trend of Policy for Remotely Piloted Aircraft System Panel in International Civil Aviation Organization (국제민간항공기구의 무인기 정책 개발 동향)

  • Ahn, Hyojung;Won, Jungyun
    • Transactions of the KSME C: Technology and Education
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    • v.4 no.2
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    • pp.117-122
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    • 2016
  • Ecumenically, RPAS(Remotely Piloted Aircraft System) operation has been increased and the related accidents also have occurred. Accordingly, national authorities, organizations and industry have been striving for amendment and enactment of policy and regulation related to the RPAS(Remotely Piloted Aircraft System) operation. And ICAO had performed the joint study to make international standards through UASSG(Unmanned Aerial System Study Group). Recently this group has been switched to the panel meeting, RPASP(Remotely Piloted Aircraft System Panel). It has been discussed to make the related annex, SARPs(Standards and Recommended Practices) and etc. in RPASP. In this paper, we investigated the trend of study and development for ICAO RPAS policy and regulation. Based on these results, we suggested considerations to prepare domestic policy and regulations.

Simulation of a Double Effect Double Stage Absorption Heat Pump for Usage of a Low Temperature Waste Heat (저온 폐열 활용을 위한 2중 효용 2단 흡수식 히트펌프 시뮬레이션)

  • Kim, Nae-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7736-7744
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    • 2015
  • Considering the significant waste of industrial energy, effective use of low temperature waste heat is extremely important. In this study, a heat pump cycle with double effect and double stage was realized, which escalates the hot water temperature from $50^{\circ}C$ to $70^{\circ}C$ using $160^{\circ}C$ high temperature heat source and $17^{\circ}C$ low temperature heat source. The steam generated in the first generator condenses in the first condenser generating steam in the second generator. The steam condenses in the second condenser and is provided to the second evaporator. Part of the water out of the second evaporator is supplied to the first evaporator, which evaporates using low temperature waste heat. The evaporated steam enters the first absorber and the second evaporator. The steam out of the second evaporator is absorbed into the solution at the second absorber. The hot water temperature is raised in the second condenser and in the second absorber. Proper flow rates and UA values, which satisfied temperature lift $20^{\circ}C$ and COP 1.6, were deduced through trior and error. The COP increases as the temperature of the high temperature water increases, hot water temperature decreases and flow rate increases, waste water temperature and flow rate increases, solution circulation rate decreases. On the other hand, the temperature rise of the hot water increases as the temperature of the high temperature water increases, hot water temperature increases and flow rate decreases, waste water temperature and flow rate increases, solution circulation rate increases. In addition, the COP and hot water temperature rise increase as UAs of the heat exchangers increase.

A $G_{4}$ Sequence within PHR1 Promoter Acts as a Gate for Cross-Talks between Damage-Signaling Pathway and Multi-Stress Response

  • Jang, Yeun-Kyu;Kim, Eun-Mi;Park, Sang-Dai
    • Animal cells and systems
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    • v.6 no.3
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    • pp.271-275
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    • 2002
  • Rph1 and Gisl are damage-responsive repressors involved in PHR1 expression. They have two $C_{2}$H/ sub 2/ zinc finger motifs as putative DNA binding domains and N-terminal conserved domain with unknown function. They are also found in the human retinoblastoma binding protein 2 and the mouse jumonji- encoded protein. The repressors are able to bind to A $G_{4}$ sequence within a 39-bp sequence called upstream repressing sequence of PHR1 promoter (UR $S_{PHR1}$) responsible for the damage-response of PHR1. We report here that Rph1 is predominantly localized in the nucleus as examined by fluorescence microscopic analysis with GFP-Rph1 fusion protein. On the basis of the fact that the A $G_{4}$ sequence that is recognized by Rph1 and Gisl is also recognized by Msn2 and Msn4 in a process of stress response, we a1so tried to examine the in vivo function of A $G_{4}$ and the role of Msn2 and Msn4 in PHR1 expression. Our results demonstrate that Msn2 and Msn4 are actually required for the basal transcription of PHR1 expression but not for its damage induction. When A $G_{4}$ sequence was inserted into the minimal promoter of the cyc1-LacZ reporter, the increased LacZ expression was observed indicating its involvement in transcriptional activation. The data suggest that the A $G_{4}$ is primarily required for basal transcriptional activation of PHR1 or CYC1 promoter through the possible involvement of Msn2 and Msn4. However, since the A $G_{4}$ is also involved in the repression of PHR1 via Rphl and Gisl, it is proposed that A $G_{4}$ functions as either URS or upstream activating sequence (UAS) depending on the promoter context.t.

Type 2 Absorption Cycle to Transport Energy in the Long Distance for District Cooling Application (지역냉방 적용을 위한 LNG냉열 장거리 수송용 제 2종 흡수식 시스템)

  • Cho Young Kyong;Kim Jin-Kyeong;Oh Min Kyu;Kang Yong Tae
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.3
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    • pp.250-255
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    • 2005
  • The objective of this paper is to develop a new energy transport system for district cooling application by using type 2 absorption cycle. Cold energy from the LNG storage system is utilized as the cooling source of the condenser and the rectifier. The pressures of the system, UAs of the evaporator and the desorber, and the inlet temperatures of the refrigerant to each component are considered as the key parameters. The results show that UA of the evaporator is more dominant parameter on COP than that of the desorber and the optimum system pressure for the demand side is estimated as 525 kPa. For the present system, it is recommended that the refrigerant inlet temperature of the evaporator be lower than $4.3^{\circ}C$ for long-distance transportation. It is concluded that the cold energy from the LNG storage system can be effectively applied to the long-distance transportation system for district cooling application with the type 2 absorption cycle. The optimum operation conditions are also predicted from the parametric analysis.