• Title/Summary/Keyword: Conversion Energy

Search Result 3,344, Processing Time 0.039 seconds

Characteristics of Corrosion and Water Quality in Simulated Reclaimed Water Distribution Pipelines (모형 재이용관을 이용한 하수재이용수의 부식 및 수질영향 연구)

  • Kang, Sung-Won;Lee, Jai-Young;Lee, Hyun-Dong;Kim, Gi-Eun;Kwak, Pill-Jae
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.34 no.7
    • /
    • pp.473-479
    • /
    • 2012
  • Water reuse has been highlighted as a representative alternative to solve the lacking water resource. This study carried out a study on the pipe corrosion and water quality change which can occur through the supply of reclaimed water, using a simulated reclaimed water distribution pipeline. Galvanized steel pipe (GSP), cast iron pipe (CIP), stainless steel pipe (STSP) and PVC pipe (PVCP) were used for the pipe materials. Reclaimed water(RW) and tap water(TW) were respectively supplied into simulated reclaimed water distribution pipelines. As a result of performing a loop test to supply reclaimed water to simulated reclaimed water distribution pipelines, the weight reduction of pipe coupons showed the sequence of CIP > GSP > STSP ${\approx}$ PVCP. In addition, reclaimed water showed a high corrosion rate comparing to that of tap water. In case of CIP, the initial corrosion rate showed 3.511 mdd(milligrams per square decimeter per day) for reclaimed water and 2.064 mdd for tap water and the corrosion rate for 90 days showed 0.833 mdd for reclaimed water and 0.294 mdd for tap water. Also in case of GSP, the initial corrosion rate showed 2.703 mdd for reclaimed water and 2.499 mdd for tap water and the corrosion rate for 90 days showed 0.349 mdd for reclaimed water and 0.248 mdd for tap water, which was a tendency similar to that appeared in CIP with a tendency to reduce the corrosion rate. As a result of water quality changes of reclaimed water at pipe materials to carry out the loop test, there was higher conversion ratio of ammonia into nitrate in CIP and GSP with higher corrosion rate than that in STSP and PVCP where no corrosion has occurred. The highest denitrification rate of nitrate could be observed from CIP with the most particles generated from corrosion. In CIP, it could be confirmed that there was MIC (Microbiologically Induced Corrosion) as a result of EDS (Energy Dispersive X-ray spectrometer System) analysis results.

Effects of Feeding Split Diets for a.m. and p.m. on Laying Hen Performance and Feed Cost (산란계에 대한 오전용 사료와 오후용 사료의 별도 급여가 산란능력과 경제성에 미치는 영향)

  • 이규호;정연종
    • Korean Journal of Poultry Science
    • /
    • v.23 no.1
    • /
    • pp.27-37
    • /
    • 1996
  • This experiment was carried out to study the effects of feeding split diets for a.m. and p.m. on laying hen performance and feed cost with 480 ISA Brown layers for three periods during 32∼36, 52∼56 and 72∼76 wk of age, respectively. The control group(C) was fed a conventional single diet throughout the day and split diet groups (T$_1$, T$_2$, T$_3$, T$_4$ and T$\_$5/) were offered high energy-high protein-low Ca diets, and low energy-low protein-high Ca diets in a.m. and p.m., respectively. In split diet groups, feed intake, ME and CP consumption, and feed cost were significantly reduced(P<0.05) compared to the C, while the hen-day egg production was significantly improved. However, the average egg weight was not influenced by the feeding system. Due to the reduced daily feed, ME, and CP intakes, and the improved egg production, the conversions of feed, ME, CP, and feed cost required per kg egg mass were also significantly improved (P<0.05) in splits diet groups. Among split diet groups, the T$_2$ group fed the diet devoid of Ca supplement from the conventional laying hen diet in a.m., and the diet containing the Ca supplement 2 times the conventional diet in p.m., was superior in conversion of nutrients and feed cost per kg egg mass to the other split diet groups. It was concluded that daily feed and nutrients cousumption and daily feed cost could be reduced 5∼6% while hen-day egg production could be improved about 4%, so that about 10% of the feed and nutrients and feed cost per kg egg mass could be spared by introducing the split diet feeding for a.m. and p.m. based on T$_2$ treatment in laying hens.

  • PDF

Development of a Retrieval Algorithm for Adjustment of Satellite-viewed Cloudiness (위성관측운량 보정을 위한 알고리즘의 개발)

  • Son, Jiyoung;Lee, Yoon-Kyoung;Choi, Yong-Sang;Ok, Jung;Kim, Hye-Sil
    • Korean Journal of Remote Sensing
    • /
    • v.35 no.3
    • /
    • pp.415-431
    • /
    • 2019
  • The satellite-viewed cloudiness, a ratio of cloudy pixels to total pixels ($C_{sat,\;prev}$), inevitably differs from the "ground-viewed" cloudiness ($C_{grd}$) due to different viewpoints. Here we develop an algorithm to retrieve the satellite-viewed, but adjusted cloudiness to $C_{grd} (C_{sat,\;adj})$. The key process of the algorithm is to convert the cloudiness projected on the plane surface into the cloudiness on the celestial hemisphere from the observer. For this conversion, the supplementary satellite retrievals such as cloud detection and cloud top pressure are used as they provide locations of cloudy pixels and cloud base height information, respectively. The algorithm is tested for Himawari-8 level 1B data. The $C_{sat,\;adj}$ and $C_{sat,\;prev}$ are retrieved and validated with $C_{grd}$ of SYNOP station over Korea (22 stations) and China (724 stations) during only daytime for the first seven days of every month from July 2016 to June 2017. As results, the mean error of $C_{sat,\;adj}$ (0.61) is less that than that of $C_{sat,\;prev}$ (1.01). The percent of detection for 'Cloudy' scenario of $C_{sat,\;adj}$ (73%) is higher than that of $C_{sat,\;prev}$ (60%) The percent of correction, the accuracy, of $C_{sat,\;adj}$ is 61%, while that of $C_{sat,\;prev}$ is 55% for all seasons. For the December-January-February period when cloudy pixels are readily overestimated, the proportion of correction of $C_{sat,\;adj$ is 60%, while that of $C_{sat,\;prev}$ is 56%. Therefore, we conclude that the present algorithm can effectively get the satellite cloudiness near to the ground-viewed cloudiness.

Analysis of media trends related to spent nuclear fuel treatment technology using text mining techniques (텍스트마이닝 기법을 활용한 사용후핵연료 건식처리기술 관련 언론 동향 분석)

  • Jeong, Ji-Song;Kim, Ho-Dong
    • Journal of Intelligence and Information Systems
    • /
    • v.27 no.2
    • /
    • pp.33-54
    • /
    • 2021
  • With the fourth industrial revolution and the arrival of the New Normal era due to Corona, the importance of Non-contact technologies such as artificial intelligence and big data research has been increasing. Convergent research is being conducted in earnest to keep up with these research trends, but not many studies have been conducted in the area of nuclear research using artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. This study was conducted to confirm the applicability of data science analysis techniques to the field of nuclear research. Furthermore, the study of identifying trends in nuclear spent fuel recognition is critical in terms of being able to determine directions to nuclear industry policies and respond in advance to changes in industrial policies. For those reasons, this study conducted a media trend analysis of pyroprocessing, a spent nuclear fuel treatment technology. We objectively analyze changes in media perception of spent nuclear fuel dry treatment techniques by applying text mining analysis techniques. Text data specializing in Naver's web news articles, including the keywords "Pyroprocessing" and "Sodium Cooled Reactor," were collected through Python code to identify changes in perception over time. The analysis period was set from 2007 to 2020, when the first article was published, and detailed and multi-layered analysis of text data was carried out through analysis methods such as word cloud writing based on frequency analysis, TF-IDF and degree centrality calculation. Analysis of the frequency of the keyword showed that there was a change in media perception of spent nuclear fuel dry treatment technology in the mid-2010s, which was influenced by the Gyeongju earthquake in 2016 and the implementation of the new government's energy conversion policy in 2017. Therefore, trend analysis was conducted based on the corresponding time period, and word frequency analysis, TF-IDF, degree centrality values, and semantic network graphs were derived. Studies show that before the 2010s, media perception of spent nuclear fuel dry treatment technology was diplomatic and positive. However, over time, the frequency of keywords such as "safety", "reexamination", "disposal", and "disassembly" has increased, indicating that the sustainability of spent nuclear fuel dry treatment technology is being seriously considered. It was confirmed that social awareness also changed as spent nuclear fuel dry treatment technology, which was recognized as a political and diplomatic technology, became ambiguous due to changes in domestic policy. This means that domestic policy changes such as nuclear power policy have a greater impact on media perceptions than issues of "spent nuclear fuel processing technology" itself. This seems to be because nuclear policy is a socially more discussed and public-friendly topic than spent nuclear fuel. Therefore, in order to improve social awareness of spent nuclear fuel processing technology, it would be necessary to provide sufficient information about this, and linking it to nuclear policy issues would also be a good idea. In addition, the study highlighted the importance of social science research in nuclear power. It is necessary to apply the social sciences sector widely to the nuclear engineering sector, and considering national policy changes, we could confirm that the nuclear industry would be sustainable. However, this study has limitations that it has applied big data analysis methods only to detailed research areas such as "Pyroprocessing," a spent nuclear fuel dry processing technology. Furthermore, there was no clear basis for the cause of the change in social perception, and only news articles were analyzed to determine social perception. Considering future comments, it is expected that more reliable results will be produced and efficiently used in the field of nuclear policy research if a media trend analysis study on nuclear power is conducted. Recently, the development of uncontact-related technologies such as artificial intelligence and big data research is accelerating in the wake of the recent arrival of the New Normal era caused by corona. Convergence research is being conducted in earnest in various research fields to follow these research trends, but not many studies have been conducted in the nuclear field with artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. The academic significance of this study is that it was possible to confirm the applicability of data science analysis technology in the field of nuclear research. Furthermore, due to the impact of current government energy policies such as nuclear power plant reductions, re-evaluation of spent fuel treatment technology research is undertaken, and key keyword analysis in the field can contribute to future research orientation. It is important to consider the views of others outside, not just the safety technology and engineering integrity of nuclear power, and further reconsider whether it is appropriate to discuss nuclear engineering technology internally. In addition, if multidisciplinary research on nuclear power is carried out, reasonable alternatives can be prepared to maintain the nuclear industry.

Difference in Chemical Composition of PM2.5 and Investigation of its Causing Factors between 2013 and 2015 in Air Pollution Intensive Monitoring Stations (대기오염집중측정소별 2013~2015년 사이의 PM2.5 화학적 특성 차이 및 유발인자 조사)

  • Yu, Geun Hye;Park, Seung Shik;Ghim, Young Sung;Shin, Hye Jung;Lim, Cheol Soo;Ban, Soo Jin;Yu, Jeong Ah;Kang, Hyun Jung;Seo, Young Kyo;Kang, Kyeong Sik;Jo, Mi Ra;Jung, Sun A;Lee, Min Hee;Hwang, Tae Kyung;Kang, Byung Chul;Kim, Hyo Sun
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.34 no.1
    • /
    • pp.16-37
    • /
    • 2018
  • In this study, difference in chemical composition of $PM_{2.5}$ observed between the year 2013 and 2015 at six air quality intensive monitoring stations (Bangryenogdo (BR), Seoul (SL), Daejeon (DJ), Gwangju (GJ), Ulsan (US), and Jeju (JJ)) was investigated and the possible factors causing their difference were also discussed. $PM_{2.5}$, organic and elemental carbon (OC and EC), and water-soluble ionic species concentrations were observed on a hourly basis in the six stations. The difference in chemical composition by regions was examined based on emissions of gaseous criteria pollutants (CO, $SO_2$, and $NO_2$), meteorological parameters (wind speed, temperature, and relative humidity), and origins and transport pathways of air masses. For the years 2013 and 2014, annual average $PM_{2.5}$ was in the order of SL ($${\sim_=}DJ$$)>GJ>BR>US>JJ, but the highest concentration in 2015 was found at DJ, following by GJ ($${\sim_=}SJ$$)>BR>US>JJ. Similar patterns were found in $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$. Lower $PM_{2.5}$ at SL than at DJ and GJ was resulted from low concentrations of secondary ionic species. Annual average concentrations of OC and EC by regions had no big difference among the years, but their patterns were distinct from the $PM_{2.5}$, $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ concentrations by regions. 4-day air mass backward trajectory calculations indicated that in the event of daily average $PM_{2.5}$ exceeding the monthly average values, >70% of the air masses reaching the all stations were coming from northeastern Chinese polluted regions, indicating the long-range transportation (LTP) was an important contributor to $PM_{2.5}$ and its chemical composition at the stations. Lower concentrations of secondary ionic species and $PM_{2.5}$ at SL in 2015 than those at DJ and GJ sites were due to the decrease in impact by LTP from polluted Chinese regions, rather than the difference in local emissions of criteria gas pollutants ($SO_2$, $NO_2$, and $NH_3$) among the SL, DJ, and GJ sites. The difference in annual average $SO{_4}^{2-}$ by regions was resulted from combination of the difference in local $SO_2$ emissions and chemical conversion of $SO_2$ to $SO{_4}^{2-}$, and LTP from China. However, the $SO{_4}^{2-}$ at the sites were more influenced by LTP than the formation by chemical transformation of locally emitted $SO_2$. The $NO_3{^-}$ increase was closely associated with the increase in local emissions of nitrogen oxides at four urban sites except for the BR and JJ, as well as the LTP with a small contribution. Among the meterological parameters (wind speed, temperature, and relative humidity), the ambient temperature was most important factor to control the variation of $PM_{2.5}$ and its major chemical components concentrations. In other words, as the average temperature increases, the $PM_{2.5}$, OC, EC, and $NO_3{^-}$ concentrations showed a decreasing tendency, especially with a prominent feature in $NO_3{^-}$. Results from a case study that examined the $PM_{2.5}$ and its major chemical data observed between February 19 and March 2, 2014 at the all stations suggest that ambient $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations are not necessarily proportional to the concentrations of their precursor emissions because the rates at which they form and their gas/particle partitioning may be controlled by factors (e.g., long range transportation) other than the concentration of the precursor gases.

Solution Phase Photolyses of Substituted Diphenyl Ether Herbicides under Simulated Environmental Conditions (모조(模造) 환경조건하(環境條件下)에서의 치환(置換) Diphenyl Ether 제초제(除草劑)의 광분해(光分解)에 관(關)한 연구(硏究))

  • Lee, Jae-Koo
    • Applied Biological Chemistry
    • /
    • v.17 no.3
    • /
    • pp.149-176
    • /
    • 1974
  • Eight substituted diphenyl ether herbicides and some of their photoproducts were studied in terms of solution phase photolysis under simulated environmental conditions by using a Rayonet photochemical reactor. The test compounds absorbed sufficient light energy at the wavelength of 300 nm to undergo various photoreactions. All the photoproducts were confirmed by means of tlc, glc, ir, ms, and/or nmr spectrometry. The results obtained are summarized as follows: Solution phase photolysis of C-6989: An exceedingly large amount of p-nitrophenol formed strongly indicates the readiness of the ether linkage cleavage of this compound as the main reaction in all solvents used. Photoreduction of nitro to amino group(s) and photooxidation of trifluoromethyl to carboxyl group were recognized as minor reactions. Aqueous photolysis of p-nitrophenol: Quinone(0.28%), hydroquinone (0.66%), and p-aminophenol (0.42%) were confirmed as photoproducts, in addition to a relatively small amount of an unknown compound. The mechanisms of formation of these products were proposed to be the nitro-nitrite rearrangement via $n{\rightarrow}{\pi}^*$ excitation and the photoreduction through hydrogen abstractions by radicals, respectively. Solution phase photolysis of Nitrofen: Photochemical reduction leading to the p-amino derivative was the main reaction in n-hexane. In aqueous solution, the photoreduction of nitro to amino group and hydroxylation predominated over the ether linkage cleavage. Nucleophilic displacement of the nitro group by hydroxide ion and replacement of chlorine substituents by hydroxyl group or, to a lesser extent, hydrogen were also observed as minor reactoins. Solution phase photolysis of MO-338: Photoreduction of the nitro to amino group was marked in the n-hexane solution photolysis. In the aqueous solution, photoreduction of the nitro substituent and hydroxylation were the main reactions with replacement of chlorine substituents by the hydroxyl group and hydrogen, and cleavage of the ether linkage as minor reactions. Photolyses of MC-4379, MC-3761, MC-5127, MC-6063, and MC-7181 in n-hexane and cyclohexane: Photoreduction of the nitro group leading to the corresponding amino derivative and replacement of one of the halogen substituents by hydrogen from the solvent used were the key reactions in each compound. Aqueous photolysis of MC-4379: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, hydroxylation, and replacement of the nitro by hydroxy group were prominent with photoreduction and dechlorination as minor reactions. Aqueous photolysis of MC-3761: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, and photoreduction followed by hydroxylation were the main reactions. Aqueous photolysis of MC-5127: Replacement of carboxyethyl by hydrogen was predominant with ether linkage cleavage, photoreduction, and dechlorination as minor reactions. It was obvious that the decarboxyethylation proceeded more readily than decarboxymethylation occurring in the other compounds. Aqueous photolysis of MC-6063: Cleavage of the ether linkage and photodechlorination were the main reactions. Aqueous photolysis of MC-7181: Replacement of the carboxymethyl group by hydrogen and monodechlorination were the remarkable reactions. Cleavage of the ether linkage and hydroxylation were thought to be the minor reactions. Aqueous photolysis of 3-carboxymethyl-4-nitrophenol: The photo-induced Fries rearrangement common to aromatic esters did not appear to occur in the carboxymethyl group of this type of compound. Conversion of nitro to nitroso group was the main reaction.

  • PDF

Metabolism of $C^{14}-1-glucose$ and $C^{14}-6-glucose$ by the Ehrlich Ascites Turner Tissue (에르릿히 복수종양의 $C^{14}-1-$ 포도당 및 $C^{14}-6-$포도당 대사에 관한 연구)

  • Kwon, Chang-Rak
    • The Korean Journal of Physiology
    • /
    • v.1 no.1
    • /
    • pp.33-41
    • /
    • 1967
  • The metabolic patterns of C-1 and C-6-carbon atoms of glucose were observed in the tissue homogenates of the Ehrlich ascites tumor tissue which was incubated for 3 hours in the Dubnuff metabolic shaking incubator. $C^{14}-1-and\;C^{14}-6-glucose$ were used as tracers. The glucose media in which tissue homogenate was incubated was kept at a concentration of 200mg% glucose of carrier and appropriate amount of $C^{14}-1-or\;C^{14}-6-tracer$. At the end of 3 hour incubation, respiratory $CO_2$ samples trapped by alkaline which is placed in the tenter well of incubation flask were analyzed for the total $CO_2$ production rates and their radioactivities. The tissue homogenate samples after incubation were analyzed for their concentrations of glucose, lactate, pyruvate and glycogen and calculations were made on the glucose consumption rate, pyruvate and lactate accumulation rates. The following results were obtained. Data obtained in each group are as follows: 1. In the tissue homogenate, which was incubated with $C^{14}-1-glucose as a substrate, total $CO_2$ production rate averaged $19.0{\pm}5.0{\mu}M/hr/gm$ and the mean specific activity of respiratory $CO_2$ was $840{\pm}296\;cpm/mgC.$ Relative specific activity (RSA) which means the fraction of $CO_2$ derived from medium $C^{14}-1-glucose$ to total $CO_2$ production rate was calculated by ratio of SA of respiratory $CO_2$ and medium $C^{14}-1-glucose.$ RSA was $14.3{\pm}5.0%,$ Accordingly actual $CO_2$ production rate from medium $C^{14}-1-glucose$ showed a mean value of $2.79{\pm}1.35\;{\mu}m$ of which amount was equivalent to the mean value of total glucose consumption rate $(RGDco_2)$, namely, $5.1{\pm}1.3%.$ Lactate and pyruvate appearance rates averaged $7.13{\pm}1.26\;and\;0.21{\pm}0.02{\mu}M/hr/gm,$ respectively. Assuming that these 3 carbon compounds appeared in the medium were derived from glucose, calculations were made that relative glucose disappearance rate into lactate $(RGD_L)$ was $38.0{\pm}5.4%\;and\;RGD_P$ was $1.23{\pm}0.03%.$ Therefore, about 43.3% of the total glucose consumed were accounted for by conversion into the respiratory $CO_2$, lactate and pyruvate. 2. In the second group, which was incubated with $C^{14}-1-glucose$ as a substrate, glucose consumption rate, lactate and pyruvate appearance rates showed almost the same order as the values of the $C^{14}-1-glucose$ substrate group. However, RSA was remarkably decreased showing a mean value of $1.02{\pm}0.13%.$ This fact means that the C-6 carbon of glucose take the minor part in the oxidative metabolism of glucose. The glycogen level in both substrate tissue homogenate showed less than 0.3% of tissue weight. These low value suggested that there was an inhibition of carbohydrate synthesis in the Ehrlich ascites tumor tissue. 3. The catabolic pathway of glucose in the tumor tissue were analyzed on the basis of Bloom's principle from the values of RSA. It was found that in the tumor tissue more than 90% of $CO_2$ derived from glucose were oxidized via the alternate pathway other than principal EMP-TCA cycle such as hexose monophosphate pathway (HMP). From the data described above, it was assumed that in the Ehrlich tumor tissue anaerobic glycolysis proceeds normally although, the oxidation of products of anaerobic glycolysis via the TCA cycle is inhibited resulting in the accumulation of lactate and almost all of oxidative energy from glucose is released by oxidative pathway such as HMP.

  • PDF

Effect of Breed (Lean or Fat Pigs) and Sex on Performance and Feeding Behaviour of Group Housed Growing Pigs in a Tropical Climate

  • Renaudeau, D.;Giorgi, M.;Silou, F.;Weisbecker, J.L.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.4
    • /
    • pp.593-600
    • /
    • 2006
  • The effects of breed and sex on individual growth performance and feeding behaviour were studied between 45 and 90 kg BW in two replicates of forty group-housed pigs. The first and the second replicates were carried out during the warm season (i.e. between February and April 2003) and during the hot season (i.e. between August and October 2003), respectively. During the warm season, ambient temperature and relative humidity averaged $25.3^{\circ}C$ and 86.0%. The corresponding values for the hot season were $27.9^{\circ}C$ and 83.6%. The pigs were grouped in pens of 10 animals on the basis of breed (Creole or Large White) and sex (gilt or castrated male) and given ad libitum access to a grower diet (9.0 MJ/kg net energy and 158 g/kg crude protein) via feed intake recording equipment (Acema 48). An ear-tag transponder was inserted into each pig and this allowed the time, duration, and size of individual visits to be recorded. The growth performance and feeding pattern were significantly affected by breed, sex, and season. The Creole pigs (CR) had a lower average daily gain (ADG) (642 vs. 861 g/d, p<0.01) and carcass lean content ($LC_{90kg}$) (35.4 vs. 54.5%; p<0.01) and a higher backfat thickness at 90 kg BW ($BT_{90kg}$) (23.4 vs. 10.4 mm; p<0.01) than Large White pigs (LW) whereas the average daily feed intake (ADFI) was not affected by breed (2.34 vs. 2.22 kg/d, respectively for CR and LW pigs; p>0.10). Consequently, the food:gain ratio was higher in CR than in LW (3.65 vs. 2.58; p<0.01). CR had less frequent meals but ate more feed per meal than LW (5.9 vs. 8.8 meals/d and 431 vs. 279 g/meal; p<0.01). The rate of feed intake was lower (27.6 vs. 33.9 g/min; p<0.01) and the ingestion time per day and per meal were higher in CR than in LW (87.1 vs. 69.7 min/d and 15.8 vs. 8.4 min/meal; p<0.01). The ADFI and BT90 kg were higher (2.38 vs. 2.17 kg/d and 18.1 vs. 15.9 mm; p<0.05) and LC90 kg was lower (43.5 vs. 46.4%; p<0.01) in castrated males (CM) than in gilts (G) whereas ADG was not affected by sex (p = 0.12). The difference in lean content between CM and G was greater in CR than in LW. The ADFI and ADG were reduced during the hot season (2.18 vs.2.38 kg/d and 726 vs. 777 g/d, respectively; p<0.05) whereas feed conversion and carcass lean content were not affected by season (p>0.05). Average feeding time per meal and meal size decreased during the hot season (10.9 vs. 13.2 min/meal and 316 vs. 396 g/meal; p<0.01) whereas the rate of feed intake was not affected by season (p = 0.83). On average, 0.69 of total feed intake was consumed during the diurnal period. However, this partition of feed intake was significantly affected by breed, sex, and season. In conclusion, the breed, sex and season significantly affect performance and feeding pattern in growing pigs raised in a tropical climate. Moreover, the results obtained in the present study suggest that differences observed in BW composition between CR and LW are associated with difference in feeding behaviour, in particular, the short-term regulation of feed intake.

Optimum Dissolved Oxygen Level for the Growth of Tilapia in the Recirculating Water System (순환여과식사육장치에서 틸라피아의 성장을 위한 최적용존산소량)

  • KIM In-Bae;WOO Young-Bae
    • Journal of Aquaculture
    • /
    • v.1 no.1
    • /
    • pp.67-73
    • /
    • 1988
  • A growth experiment of tilapia (offsprings of the hybrid between Oreochromis niloticus and O. mossambicus) under different dissolved oxygen levels in the recirculating water system was conducted at the Fish Culture Experiment Station of the National Fisheries University of Pusan from February 4 to March 5, 1986. Six tanks with a capacity of $1.8m^3$ of water each were used under the same condition of water parameters except for dissolved oxygen levels which were designated to maintain at 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 mg/$\iota$. Each tank was stocked with 90 kg of fish each averaging 64 to 69 grams. The average water temperature during the course of the experiment was $22.5^{\circ}C$. The results obtained are summarized as follows: The food conversion efficiencies were very good, being 1.05-1.11 at 3.5, 3.0, 2.5 and 2.0 mg/$\iota$ DO levels without any significant differences among them, but at 4.0 mg/$\iota$ the F. C. was 1.39 and at 1.5 mg/$\iota$ it was 1.61 being very poor compared with the others. The daily growth rate performance was best at 3.5 mg/$\iota$ dissolved oxygen level followed by 3.0 and 2.5 mg/$\iota$ with slight differences while at 4.0 and 2.0 mg/$\iota$ DO levels the growths were significantly poor, and at 1.5 mg/$\iota$ DO level it was extremely poor. In 1.5 mg/$\iota$ group, the fish did not accept feed vigorously and after feeding the fish usually concentrated around the inflow point showing oxygen deficiency response. While at 4.0 mg/$\iota$ high feeding rates tended to waste significant amounts of feed while eating and led to water deterioration, and above these levels the results is considered to lead to a waste of energy with uneconomical performance. On the other hand, at and below 2.0 mg/$\iota$ DO level the tilapia certainly showed a poor growth performance. The experiment indicates that the DO range of 2.5$\~$3.5 mg/$\iota$ is the optimum level for the good growth performance.

  • PDF

Effects of Cudrania tricuspidata Fruit on the Performance, Blood Metabolites and IgG in Laying Hens (꾸지뽕 열매의 급여가 산란계의 생산능력, 혈액 성상, 면역글로불린에 미치는 영향)

  • Lim, Chun Ik;Choi, Hong Hwan;Choi, Seung Min;Lee, Dong Gil;Kang, Min Su;Lee, Bom Mi;Kim, Hyeong Ju;Shin, Min Kyeong;Lee, A Ra;Ryu, Kyeong Seon
    • Korean Journal of Poultry Science
    • /
    • v.43 no.1
    • /
    • pp.15-20
    • /
    • 2016
  • This research was carried out to determine the effect of Cudrania tricuspidata fruit (CTF) on the performance of laying hens, egg quality, yolk fatty acid composition, Immunoglobulin G (IgG) and blood composition. A total 288 Brown Nick laying hens of 48 weeks old replaced into 4 groups with 4 replicates of 18 birds in each. Treatments were added with 0, 0.25, 0.5, 1.0% CTF containing dried seed and pulp. Metabolizable energy (ME) and crude protein (CP) were 2,800 kcal/kg and 16.0% in basal diets, respectively. Egg production and daily eggmass were significantly increased in 1.0% CTF addition treatment compared to those of other treatments (P<0.05). Egg weight and feed intake were not different among treatments. Feed conversion ratio showed the lower result in 1.0% CTF treatment than other treatments (P<0.05). Eggshell color was not influenced by the addition of CTF. Albumin height, Haugh unit and eggshell breaking strength was not statistically different, but seemed to be higher as dietary CTF addition increased. Yolk color was increased as dietary CTF increased and was the highest in 1.0% CTF group (P<0.05). Fatty acids were not shown the consistency in yolk. Blood cholesterol and triglyceride (TG) of birds fed CTF were significantly low compared to those of control. IgG was also statistically higher in CTF treatments than control (P<0.05). As the results of this experiment, the addition of 1% CTF would be the most effective on performance and egg quality, whereas the 0.25% CTF addition in basal diets seemed to be optimum to improve the blood cholesterol, TG,high density lipoprotein cholesterol (HDL-CHOL), IgG in laying hens.