• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.105-112
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• 2008

Disinfection is a basic and effective microorganism inactivation method and historically contributed a decrease in waterborne diseases. To guarantee the disinfection ability, improving T in CT value is important. Many indexes are used to estimate the hydraulic efficiency, however, these are black-box analysis. Therefore it is need to develope new estimation method. In this study, internal short-circuiting estimation method (ISEM) is developed using CFD and we inquire into the factor which causes increase of $T_{10}/T$ value as LW ratio increases. And the effect of shape on the relation of LW ratio and $T_{10}/T$ is analyzed. As LW ratio increases, internal short-circuiting index (ISI) of influent and effluent zone is rapidly reduced and recirculation and dead zone are reduced in channel zone. Therefore, as the $T_{10}/T$ value converges maximum value, ISI curve is changed from "V" shape to "U" shape and hydraulic efficiency is improved especially in downstream portion of clearwell. The less the shape ratio(width/length of clearwell) is the less the $T_{10}/T$ value is at a same LW ratio because the portion of turning zone increases as shape ration decreases, therefore more boundary separation is generated.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.832-841
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• 2007

Rectal Temperature;Thermoregulation;Sows;Breed;The effects of season (hot vs. warm) in a tropical humid climate, parity (primiparous vs. multiparous) and breed (Creole: CR, Large White: LW) on rectal temperature (RT) were studied for a total of 222 lactations obtained in 85 sows (43 CR and 42 LW; 56 primiparous and 166 multiparous) over a 28-d lactation, between June 2002 and April 2005. Mean daily ambient temperature was higher during the hot season than during the warm season (26.0 vs. $24.1^{\circ}C$) and relative humidity was high and similar in both seasons (89% on average). At farrowing, BW was lower (172 vs. 233 kg) and backfat thickness was higher (37 vs. 21 mm) in CR than in LW sows (p<0.01). During the hot season, the reduction of average daily feed intake (ADFI) was more pronounced in LW than in CR sows (-920 vs. -480 g/d, p<0.05). Rectal temperature was higher at 1200 than at 0700hr, which coincides with the maximum and the minimum values of daily ambient temperature. The daily RT increased ($+0.9^{\circ}C$; p<0.01) between d -3 and d 7 (d 0: farrowing day), remained constant between d 7 and d 25 and decreased (p<0.01) thereafter (i.e. $-0.6^{\circ}C$ between d 25 and d 32). The average daily RT was significantly higher during the hot than during the warm season (38.9 vs. $38.6^{\circ}C$; p<0.01). It was not affected by breed, but the difference in RT between the hot and warm seasons was more pronounced in LW than in CR sows (+0.4 vs. $+0.2^{\circ}C$; p<0.05). Parity influenced the RT response; it was greater in primiparous than in multiparous sows (38.9 vs. $38.7^{\circ}C$; p<0.01). This study suggests that thermoregulatory responses to heat stress can differ between breeds and between parities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.15-19
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• 1985

This study was carried out to develope the equations for estimating the areas of leaflet, leaf, and total leaf for 1, 2, 3, 4, 5, and 6 years old ginseng, Panax ginseng, grown in field. The highest correlation coefficient was found between leaflet area and product of leaflet length and width(LW) in all leaflets although leaflet shape varied somewhat according to the position and plant age. It was possible to estimate area of the leaf, and total leaf by one central leaflet in a compound leaf. The equations for estimating the leafet, leaf areas of 1 year differ to those of over 2 years old plant, but there was no difference among those of 2, 3, 4, 5, and 6 years. The equations for 1 year old are A =0.64 LW, A' =A/0.38, and for 2, 3, 4, 5, and 6 years old, A =0.60 LW, A' =A/0.32, A" =A' x number of leaves of central leaflet(A), leaf(A') and total leaf areas(A"), respectively. The estimation of leaflet, leaf, total leaf areas of ginseng plant grown under 20% light-transmittance rate was possible by using the equations mentioned.

• Journal of the Korean GEO-environmental Society
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• v.13 no.4
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• pp.53-59
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• 2012

In this study, strength and durability of a geo-polymer grout material(HIT) was investigated through unconfined compression strength tests(UCS)), scanning electron microscope(SEM), elution tests, and surface observations. UCS tests showed high initial strength and rapid continuous strength increments when compared to labile wasser glass(LW) and space grouting rocket system (SGR) grout materials, which showed strength reduction after 28 days. The higher strength was also reflected in SEM results which showed calcium silicate hydroxide(C-S-H) gels of the dense hydrate range, indicating higher strength and durability. Additionally, elution tests and grout surface observations showed HIT was in good condition and the decrease in weight was minor when under water for six months. LW and SGR showed the grout surface to be constricted and lower durability due to higher weight increase. These results and observations show HIT to be better suited for coastal structural applications than LW and SGR in long terms of strength and durability.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1559-1570
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• 2008

A new grouting material named 3S is developed that can be used effectively for reinforcing cut surface of weathered rock in processing of tunneling. The new material is composed of mostly micro slag cement and general Portland cement, but the material is foundered again upto $8,000\;cm^2/g$ of specific area so that it can be easily infiltrated in to the ground. For verifying technical and engineering quality of the material several laboratory tests with specially designed test apparatus were performed including compression tests, infiltration tests and resonant column tests. It was verified that the newly developed grouting material at early age of 1 or 3 days generates 200~1500% higher compressive strength and 400~560% larger elastic modulus than those of the LW(LW-1) or micro-cement(LW-2) grouting materials in the market. In addition, the new 3S grouting material could be so easily infiltrated into the model ground in the lab tests that it produces 4 times larger grouted roots in average compared to the usual water glass type grouting material(LW-1). Thus, it can be said that the newly developed grouting material can effectively prevent inflow water into tunnel compared to LW grouting materials.

• Animal Bioscience
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• v.34 no.1
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• pp.20-25
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• 2021

Objective: The objective of the study was to investigate the possibility of utilizing an early litter size trait as an indirect selection trait for longevity and to estimate genetic parameters between sow stayability and litter size at different parities using a linear-threshold model for longevity in Thai Large White (LW) and Landrace (LR) populations. Methods: The data included litter size at first, second, and third parities (NBA1, NBA2, and NBA3) and sow stayability from first to fourth farrowings (STAY14). The data was obtained from 10,794 LR and 9,475 LW sows. Genetic parameters were estimated using the multiple-trait animal model. A linear-threshold model was used in which NBA1, NBA2, and NBA3 were continuous traits, while STAY14 was considered a binary trait. Results: Heritabilities for litter size were low and ranged from 0.01 to 0.06 for both LR and LW breeds. Similarly, heritabilities for stayability were low for both breeds. Genetic associations between litter size and stayability ranged from 0.43 to 0.65 for LR populations and 0.12 to 0.55 for LW populations. The genetic correlation between NBA1 and STAY14 was moderate and in a favorable direction for both LR and LW breeds (0.65 and 0.55, respectively). Conclusion: A linear-threshold model could be utilized to analyze litter size and sow stayability traits. Furthermore, selection for litter size at first parity, which was the genetic trait correlated with longevity, is possible when one attempts to improve lifetime productivity in Thai swine populations.

• Journal of IKEEE
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• v.24 no.4
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• pp.1064-1068
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• 2020

For LW-TLM antenna of 65 kHz, Near-field propagation characteristics due to wave propagation obstacle are analyzed in this paper. The simulation modeling for propagation effects are based on the model of actual LW-TLM antenna which utilizes the frequency of 65 kHz, and the model expressed as propagation obstacle at a mountain height and a proximity of antenna and mountain. The near-field performance are analyzed based on the parameters of simulation model. In case of a normal mountain height and distance between the adjacent mountain and antenna site, a field strength change of about 1.7 dB has occurred. Above the constant distance of propagation obstacle and antenna, the wave propagation characteristics of disregarding the effects of propagation obstacle are shown. The results of this paper can be used to design and build a transmitting antenna site with 65 kHz operating frequency.

• Asian Journal of Turfgrass Science
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• v.1 no.1
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• pp.37-41
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• 1987

Effect of Rolling factor on the growth and thatch accumulation in tall fescue was studied from the viewpoint of estimate the rolling factor to obtain the highest values of growth characters and analysis of thatch accumulation. Rolling factors were 1.82, 3.33, 4.29 and 4.85, respectively. The results are may he summarized as follows ; 1. Rolling factor was affected to obstructive on the growth of tall fescue. Thus, the rolling factor ( RF) had significant negative correlated with the dry weight of plant ( DW ), leaf weight (LW), stem weight (SW), dry weight of thatch (Th), number of tillers (NT) and C / F ratio. 2. Rolling factor of 1.82 was an adequate rolling factor for the growth. 3. The dry weight of thatch(Th) had significant positive correlated with DW, LW, and NT, but negative correlated with the dry weight of thatch per a tiller ( th / NT). 4. Thatch accumulation system can be shown in following diagram. yield compnents - DW ~ Th - Rf (LW, SW, NT, C/F) th/NT 5. The dry weight of thatch per a tiller(th / NT) was a concerning factor for the losses of thatch.

• Journal of Animal Science and Technology
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• v.57 no.9
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• pp.35.1-35.8
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• 2015

Background: An experiment was conducted in Vietnam to test the hypothesis that total dry matter (DM) intake and liveweight (LW) gain would increase in a curvilinear manner with increasing amounts of concentrate offered. Method: There were five treatments: a basal diet of Guinea grass fed at 1 % of LW and rice straw fed ad libitum (T0), or this diet supplemented with concentrate at 0.6 (T1), 1.2 (T2), 1.8 (T3), or 2.4 % of LW (T4). The concentrate comprised locally available ingredients, namely cassava chips, rice bran, crushed rice grain, fishmeal, salt, and urea, mixed manually. Results: Concentrate intake increased from T0 to T3, but there was no difference in concentrate intake between T3 and T4. Total feed intake increased in a curvilinear manner from 4.0 to 6.4 kg DM/d as the quantity of concentrate consumed increased. The substitution of concentrate for grass and rice straw increased with increasing consumption of concentrate and was as high as 0.49 kg DM reduction per kg of concentrate consumed. LW gain increased curvilinearly, with significant differences between T0 (0.092 kg/d), T1 (0.58 kg/d) and T2 (0.79 kg/d); but there were no significant differences in LW gain between T2, T3 (0.83 kg/d) and T4 (0.94 kg/d).With increasing amount of concentrate in the diet, the digestibilities of dry matter, organic matter, crude protein, and crude fat increased, but NDF digestibility decreased. Conclusion: Based on these results, young Vietnamese Brahman-cross growing cattle will respond to a locally-sourced concentrate mix offered at a level of up to 1.2 % of LW.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.12
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• pp.1736-1744
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• 2008

Two experiments were conducted in central Vietnam to test the hypothesis that supplementation with a concentrate, comprising rice bran (45% fresh basis), maize (49%), fish meal (3%), urea (2%) and salt (1%), up to 2% of live weight (LW)/d (dry matter (DM) basis) would linearly increase digestible organic matter intake and LW gain of yellow cattle. In both experiments, there were five treatments, namely a basal diet of fresh grass fed at 1.25% of LW (experiment 1, elephant grass, Pennisetum purpureum; experiment 2, native grass) and rice straw (Oryza sativa) fed ad libitum or this diet supplemented with concentrate at about 0.3, 0.7, 1.3 or 2.0% LW. There were 4 male growing cattle per treatment in experiment 1 and 3 in experiment 2. Diets were fed for 44 (experiment 1) or 49 (experiment 2) days, with feed intake recorded daily, LW measured about weekly and digestibility measurements made over 7 days commencing on day 24 (experiment 1) or day 10 (experiment 2). The elephant grass and native grass had neutral detergent fibre (NDF) concentrations of 82 and 73% DM, and nitrogen concentrations of 1.3 and 1.8% DM, respectively. The rice straw used had a NDF concentration of 79-84% DM and nitrogen concentration of 0.8% DM. The concentrate had NDF and nitrogen concentrations of 33 and 2.8% DM. In both experiments, DM intake increased (p<0.001) linearly as the amount of concentrate consumed increased. Rice straw intake declined (p<0.001) (experiment 1: 1.24 to 0.48 kg DM/d; experiment 2: 0.95 to 0.50 kg DM/d) as concentrate intake increased. Grass intake was not significantly affected by concentrate intake in either experiment. The lowest amount of concentrate supplement increased forage intake, after which substitution rate increased as the amount of concentrate consumed increased. However, substitution rates at the highest amount of concentrate consumed were modest at 0.3 to 0.5 kg DM reduction in forage intake/kg DM supplement consumed. In both experiments, digestible organic matter intake increased linearly (p<0.001) (experiment 1: 1.16 to 2.38 kg/d; experiment 2: 1.30 to 2.49 kg/d) as the amount of supplement consumed increased, as did LW gain (experiment 1: 0.15 to 0.81 kg/d; experiment 2: 0.15 to 0.77 kg/d). This was associated with significant (p<0.01) linear increases in organic matter intake and apparent organic matter digestibility. Neutral detergent fibre digestibility declined as concentrate intake increased, but the effect was not significant (p = 0.051) in experiment 2. These results are discussed in relation to existing literature and potential to improve the profitability of cattle fattening in central Vietnam.