• Title/Summary/Keyword: Odor Control

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Three-step in vitro digestion model for evaluating and predicting fecal odor emission from growing pigs with different dietary protein intakes

  • Lo, Shih-Hua;Chen, Ching-Yi;Wang, Han-Tsung
    • Animal Bioscience
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    • v.35 no.10
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    • pp.1592-1605
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    • 2022
  • Objective: The objective of this study was to select an effective in vitro digestion-fermentation model to estimate the effect of decreasing dietary crude protein (CP) on odor emission during pig production and to suggest potential prediction markers through in vitro and in vivo experiments. Methods: In the in vitro experiment, three diet formulations with different CP contents (170 g/kg, 150 g/kg, and 130 g/kg) but containing the same standardized ileal digestible essential amino acids (SID-EAA) were assessed. Each diet was evaluated by two different in vitro gastric-intestinal phase digestion methods (flask and dialysis), combined with fresh pig feces-ferment inoculation. Eighteen growing barrows (31.9±1.6 kg) were divided into three groups: control diet (180 g CP/kg, without SID-EAA adjustment), 170 g CP/kg diet, and 150 g CP/kg diet for 4 weeks. Results: The in vitro digestion results indicated that in vitro digestibility was affected by the gastric-intestinal phase digestion method and dietary CP level. According to the gas kinetic and digestibility results, the dialysis method showed greater distinguishability for dietary CP level adjustment. Nitrogen-related odor compounds (NH3-N, indole, p-cresol, and skatole) were highly correlated with urease and protease activity. The feeding study indicated that both EAA-adjusted diets resulted in a lower odor emission especially in p-cresol and skatole. Both protease and urease activity in feces were also closely related to odor emissions from nitrogen metabolism compounds. Conclusion: Dialysis digestion in the gastric-intestinal phase followed by fresh fecal inoculation fermentation is suitable for in vitro diet evaluation. The enzyme activity in the fermentation and the fecal samples might provide a simple and effective estimation tool for nitrogen-related odor emission prediction in both in vitro and in vivo experiments.

The PLL Speed Control of DC Servo Motor for Mobile Robot Drives (자립형 이동로봇 구동을 위한 직류서보전동기 PLL속도제어 시스템에 관한 연구)

  • Eum, S.O.;Hong, S.I.
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.1020-1022
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    • 1993
  • The speed control associated with do send motors for direct-drive applications of mobile robot is considered. In odor to the high-performance operation of dc servo motor, drive circuits is controlled Pulse Width Modulations. In this case, PWM driving circuit has nonliner charactristics. This circuit composed of H-type bridge with freewheeling diodes in odor to deal with storage energy of motor's inductance and also control method is developed. At resultes, speed charactristics of motor is shown lineristics. In oder to speed control of motor. The opertion of phase-locked servo system is described and a linear discrete model is developed to their behavior. Thise model discussed are the design problems, speed variation.

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A study on the burn-in test to accomplish high quality cockpit air of an ultra-sonic aircraft in the early stage of production (생산 초기 초음속 항공기 조종석의 고품질 공기 확보를 위한 burn-in test 연구)

  • Shin, Jae Hyuk;Park, Sung Jae;Seo, Dong Yeon;Jeong, Suheon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.10
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    • pp.871-876
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    • 2016
  • Abnormal odor similar with burning smell often appears at the cockpit in the beginning of ultra-sonic aircraft without air filter due to the heating of production materials remained at the bleed air duct. Sources of the odor should be removed by burn-in test before test flight in order to prevent pilot confuses order with emergency such as fire of engine. However, the present method cannot prevent abnormal odor completely at the high altitude flight because maximum temperature of flight is higher than it of burn-in-test. This paper suggests burn-in test improved based on the analysis of thermal conditions of high altitude flight. It is verified that the existing burn-in test cannot cover thermal conditions of high altitude flight due to the discontinuous flow control, high change rate of temperature per unit time and difference between limit temperature of condenser and turbine. In order to overcome the limitations of current methods, the new burn-in test with continuous flow control are suggested. The continuous flow control are achieved by ram air inlet control. The effect of suggested method are verified by ground tests and flight tests. The results show the bleed air temperature can cover the temperature of high altitude flight and prevent abnormal odor at the flight test.

Removal Characteristics of Natural Organic Matter and Taste and Odor by Advanced Water Treatment Process around the Han River Water Supply System (한강수계 고도정수처리 공정에서의 유기물과 맛·냄새의 제거특성)

  • Jae-Lim Lim;Lee, Kyung-Hyuk;Kim, Seong-Su;Chae, Seon-Ha
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.1
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    • pp.13-25
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    • 2007
  • The water treatment plants in Seoul Metropolitan Area, which are under Korea Water Resources Corporation(KOWACO)'s management, take water from Paldang Reservoir in Han River System for drinking water supply. There are taste and odor (T&O) problems in the finished water because the conventional treatment processes do not effectively remove the T&O compounds. As part of countermeasures for taste and odor control, KOWACO is planning to introduce advanced water treatment process such as ozone and GAC in near future. This study evaluated the removal characteristics of T&O and dissolved organic matter (DOM) to find design and operation parameters of advanced water treatment processes in a pilot-scale treatment plant. The GAC adsorption capacity for DOC in the two GAC system (GAC and $O_3$-GAC) at an EBCT of 14min was mostly exhausted after 9months. The differency of the removal efficiency of DOC between $O_3$-GAC and GAC increased with increasing operation time because the bioactivity in $O_3$-GAC process was enhanced by post-ozone process. Removal by conventional treatment was unable to reach the target TON(threshold odor number) of 3 but GAC systems at an EBCT(empty bed contact time) of 14 min were able to archive the target with few exception. During the high T&O episodes, PAC as a pretreatment together with GAC could be useful option for T&O control. However, substantial TON removal continued for more than two year (> 90,000 bed volumes). At the spiking of less concentration 26 to 61 ng/L in the influent of GAC systems, GAC absorber and $O_3$-GAC processes could meet the treatment target. The better spike control after 12 and 19 months of operation compared to that after 7 months of operation is a strong indication of biological control. The results presented in this study had shown that $O_3$-GAC process was found to be more effective for T&O control than GAC process. And the main removal mechanism in GAC systems were adsorption capacity and biodegradation.

Development of composite catalyst for hazardrous gas treatment using the heat of aviary heating equipment (계사용 온풍기를 이용한 유해가스처리 복합촉매시스템 개발)

  • Jang, Hyun-Tae;Cha, Wang-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.10
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    • pp.2779-2785
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    • 2009
  • Among the livestock, chickens are raised because of the merit ingested protein in low-priced cost of production and are primary livestock increased the consumption of meat. The factors of influencing condition, odor is the most important factor. Odor substances are ammonia, amines, hydrogen sulfide and mercaptan which come from night soil. Livestock are prevented from rearing by means of these odor substances. Though the henhouse is heated using hot air type heater in the winter season, it is ventilated for the control of odor because of the increase of odor concentration. In the present work, composite catalytic system combined the existing facilities(hot air type heater) with catalytic system was developed, it could controled odor and hazardous gas using the oxidation/reduction reaction without extra operating cost. Moreover, the purpose of this work is to develop the catalysts which are cost competitive and can maximize energy efficiency. The catalysts are noble metal(Pt-Rh) and composite transition metal(Mn) type.

Intelligent Air Quality Sensor System with Back Propagation Neural Network in Automobile

  • Lee, Seung-Chul;Chung, Wan-Young
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.468-471
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    • 2005
  • The Air Quality Sensor(AQS), located near the fresh air inlet, serves to reduce the amount of pollution entering the vehicle cabin through the HVAC(heating, ventilating, and air conditioning) system by sending a signal to close the fresh air inlet door/ventilation flap when the vehicle enters a high pollution area. One chip sensor module which include above two sensing elements, humidity sensor and bad odor sensor was developed for AQS (air quality sensor) in automobile. With this sensor module, PIC microcontroller was designed with back propagation neural network to reduce detecting error when the motor vehicles pass through the dense fog area. The signal from neural network was modified to control the inlet of automobile and display the result or alarm the situation. One chip microcontroller, Atmega128L (ATmega Ltd., USA) was used. For the control and display. And our developed system can intelligently detect the bad odor when the motor vehicles pass through the polluted air zone such as cattle farm.

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Quality Charactistics of Frozen Cookies with Buckwheat Flour (메밀가루 첨가가 냉동 쿠키의 품질 특성에 미치는 영향)

  • Lee, Hyun-Joo;Kim, Min-A;Lee, Hyun-Ja;Whang, Seong-Yun;Chung, Yoon-Kyung
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.6
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    • pp.969-974
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    • 2010
  • The purpose of this study was to investigate the quality characteristics of frozen cookies made with 3%, 6%, 9% buckwheat flour. The higher amount of buckwheat flour added to the frozen cookies, the greater the decrease in water activity, hardness, Max. G and brittleness compared to control. Lightness, redness, and yellowness of the cookies with buckwheat flour were slightly lower than those of control. Brown color and buckwheat odor of the cookies with buckwheat flour were higher, whereas egg odor and butter flavor were lower than those of control. Overall acceptance of the frozen cookies with 3% buckwheat flour was high.

Volatile Fatty Acids Production During Anaerobic and Aerobic Animal Manure Bio-treatment

  • Hong, J.H.
    • Journal of Animal Environmental Science
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    • v.13 no.3
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    • pp.219-232
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    • 2007
  • Odors from manures are a major problem for livestock production. The most significant odorous compounds in animal manure a.e volatile fatty acids(VFAs). This work reviews the VFAs from the anaerobic sequencing biofilm batch reactor(ASBBR), anaerobic sequencing batch reactor(ASBR), solid compost batch reactor(SCBR), and aerobic sequencing batch reactor(SBR) associated with the animal manure biological treatment. First, we describe and quantify VFAs from animal manure biological treatment and discuss biofiltration for odor control. Then we review certain fundamentals aspects about Anaerobic and aerobic SBR, composting of animal manure, manure compost biofilter for odorous VFAs control, SBR for nitrogen removal, and ASBR for animal wastewater treatment systems considered important for the resource recovery and air quality. Finally, we present an overview for the future needs and current experience of the biological systems engineering for animal manure management and odor control.

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By the GNC Solution, Removal Effect Offensive Odorous Compounds Generated from Food (GNC용액을 이용한 음식물 쓰레기처리장에서 발생되는 악취 규제물질 제거 효과에 관한 연구)

  • Hong, Jong-Soon;Kim, Jae-Woo
    • Journal of environmental and Sanitary engineering
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    • v.22 no.2
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    • pp.35-40
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    • 2007
  • It disposes positively in the air pollution damage which is serious, in order help period the place where it improves the quality of existence and life of the local residents. It removed the offensive odor regulation material and the technique it will be able to prevent to sleep it researched it did. After scattering the GNC solution which develops the offensive odor regulation material which occurs from the food and trash treatment plant which is located to the S from the H, company after scattering the GNC solution which it develops collection it did a control criminal record control kind air and it analyzed. In this study, we investigated the emission concentrations of offensive odorous compounds of hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide, trimethylamine, formaldehyde, acetaldehyde, propionaldehyde, buthylaldehyde, iso-valeric aldehyde, n-valeric aldehyde, ammonia. The concentrations of odorous compounds are determined by gas chromatography, HPLC and uv-vis spectroscopy. Hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide were not detected at any point examined.