• Journal of Environmental Science International
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• v.21 no.2
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• pp.189-202
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• 2012

Power spectral analysis for $PM_{10}$ observed at 10 cities in the Korean Peninsula from 2004 to 2010 was carried out to examine the spatial and temporal features of $PM_{10}$ evolution cycle. The power spectrum analysis proposed 9 typical cycles (0.5 day, 1day, 5.4day, 8~10day, 19~21day, 26day, 56day, 180day and 365day) for $PM_{10}$ evolution and the cycles are strongly associated with dilution and transportation due to the meterological influence. The spectrum intensity of 5.4day and 26day $PM_{10}$ evolution cycles mainly depend on the advection cycles of synoptic pressures system and long-term variation of climatological forcing, respectively. The intensity of $PM_{10}$ evolution with longer temporal cycles than one day tends to be stronger in La ni$\tilde{n}$a period in comparison with that in El ni$\tilde{n}$o period. Mean of typical intensity of $PM_{10}$ evolution in La ni$\tilde{n}$a period estimated to be 30% larger than El ni$\tilde{n}$o period. Thus the global scale meteorological phenomena such as El ni$\tilde{n}$o and La ni$\tilde{n}$a also can influence the variation of wind system in the Korean Peninsula and $PM_{10}$ evolution. but global scale forcing tends to influence different manner for $PM_{10}$ evolution in accordance with its temporal cycles.

• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.47-51
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• 2004

In order to know the residual pattern of pesticides and predict to the degradation period until below MRL we experimented procymidone and chlorothalonil for grape which were the most detected pesticide in grape by NAQS(National Agricultural product Quality management Service) survey. In this experiment we sprayed those pesticides 10 days before harvest and analyzed 0, 1, 2, 3, 5, 7, 10 day sample to establish logical equation and to calculate $DT_{50}$. Also the same day samples stored at $4^{\circ}C$ and $20^{\circ}C$, which were compared their degradation patterns. During the cultivating period, the residue amount of procymidone was changed from 1.85 mg/kg (0 day) to 0.33 mg/kg (10 day), $DT_{50}$ was 3.5 days, and chlorothalonil was changed from 5.5 mg/kg (0 day) to 3.49 mg/kg (10 day), $DT_{50}$ was 4.4 days. During the storage period, $DT_{50}$ of procymidone and chlorothalonil at $4^{\circ}C$ were 10.5 and 7.6 days, and 6.3 and 6.1 days at $20^{\circ}C$, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.2
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• pp.125-133
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• 2008

To investigate the effect of repeated food deprivation and refeeding on the hyperphagia, compensatory growth, feed efficiency, body composition, hepatosomatic index (HSI), and survival rate of the juvenile olive flounder Paralichthys olivaceus, an experiment was conducted for 90 days. Feeding treatments consisted of the following five regimes for 90 days from August to October, 2005: C: daily satiation feeding (control), S1: 1-day satiation feeding after 1-day food deprivation, S2: 1-day satiation feeding after 2-day food deprivation, S3: 1-day satiation feeding after 3-day food deprivation and S4: 1-day satiation feeding after 4-day food deprivation, respectively. Although the monthly feed intake (MFI) of the control was significantly higher than that of all of the starved groups, the daily feed intake (DFI) was more higher in S1, S2, and S3 than that in the control as a result of hyperphagia after starvation. While the feed efficiency in the summer (to day 30) decreased in all of the starved groups with prolongation of the starvation period, the feed efficiency in the autumn (to day 90) was increased with prolongation of the starvation period. The whole body proximate composition and HSI were also affected by starvation. The crude protein, lipid, and HSI decreased with prolongation of the starvation period, whereas the crude ash and moisture increased. The growth rate and condition factor also decreased in proportion to the starvation period. The survival rate was highest in the control and was the lowest in S4. In this study, although hyperphagia occurred in the deprived groups, we knew that the compensatory growth did not always occur.

• Journal of Veterinary Clinics
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• v.13 no.2
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• pp.114-122
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• 1996

The aim of this study was to assess the precision of the estimates of the time of estrous cycle, optimal breeding and ovulation derived by vaginal cytology. The thirteen Korea Jin-do dogs were examined the vaginal cytology, plasma estradiol-17$$\beta $ and progesterone assay during the estrous cycle. Day 0 was the day of the first male acceptance. The main change of vaginal cytology during the estrous cycle was the high proportion of anuclear cell and erythrocyte in proestrus, superficial cell, anuclear cell and erythrocyte in estrus, parabasal cell, large intermediate cell and leukocytes in diestrus, and parabasal cell and small intermediate cell in anestrus, respectively. These data indicated that vaginal cytology was reliable method for estimating estrous cycle in Korea Jin-do dogs. In the cell indices during estrus the maximum eosinoghilic index was $92.0{\pm}$2.6 (Mean{\pm} SEM$)% at Day 2 and the maximum cornification indez was $96.0{\pm}1.3%$ at Day 2, respectively. The eosinothilic indez and cornification indez of up to 70% were found at Day -1 to Day 5 and Day -6 to Day 8, and up to 80% at Day 1 to Day 4 and Day -4 to Day 6, respectively. From these data it was presumed that eosinophilic index was more reliable index for monitoring optimal breeding time than cornification indexm because eosinophilic index peak period was shorter than cornification indeX peak period and Day 2 was the day of ovulation. Therefore, optimal breeding time was the eosinophilic index peak period, more than 80% of eosinoghilic index. The $estradiol-17{\beta}$ peak, with 3 days delayed when progesterone concentration was $4.5{\pm}0.5 ng/ml$. These data estimated that the ovulation time was the day of eosinophilic index peak, Day 2. breeding time and pvulation time in Korea Jin-do dogs.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.67-74
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• 2017

PURPOSES : The objective of this study is to ascertain the curing period of cementless cold central plant recycled asphalt base-layer, using mechanical analyses and specimen quality tests on the field. METHODS : Cold central plant recycled asphalt base-layer mixture was produced in the plant from reclaimed asphalt, natural aggregate, filler for the cold mix, and the modified emulsion AP using asphalt mix design and plant mix design. In order to examine the applicability of the curing period during the field test, the international standards for the possibility of core extraction and the degree of compaction and LFWD deflection were analyzed. Moreover, Marshall stability test, porosity test, and indirect tensile strength test were performed on the specimens of asphalt mix and plant mix design. RESULTS : The plant production process and compaction method of cementless cold central plant recycled asphalt base-layer were established, and the applicability of the optical moisture content for producing the mixture was verified through the field test. In addition, it was determined that the core extraction method of the conventional international curing standard was insufficient to ensure performance, and the LFWD test demonstrated that the deflection converges after a two-day curing. However, the back-calculation analysis reveals that a three-day curing is satisfactory, resulting in a general level of performance of dense asphalt base-layer. Moreover, from the result of the specimen quality test of the asphalt mix design and plant mix design according to the curing period, it was determined that the qualities satisfied both domestic and international standards, after a two-day curing. However, it was determined that the strength and stiffness after three-day curing are higher than those after a two-day curing by approximately 3.5 % and 20 %, respectively. CONCLUSIONS:A three-day curing period is proposed for the cementless cold central plant recycled asphalt base-layer; this curing period can be demonstrated to retain the modulus of asphalt-base layer in the field and ensure stable quality characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.346-351
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• 2002

The effect of fetal number (single or twin) on plasma concentrations of progesterone, estradiol $17{\beta}$, cortisol, prolactin, growth hormone, triiodothyronine, thyroxine and insulin around parturition (periparturient period) were studied on ten $Alpine{\times}Beetle$ crossbred goats in their first to third lactation. The hormone profiles were studied on days -20, -15, -10, -5, -4, -3, -2, -1 prior to kidding and on day 0 and +1, +2, +3, +4, +5, +10, +15, +20 days postkidding. Plasma progesterone levels were significantly (p<0.01) higher in twin bearing goats comparison to single bearing goats during all the days of sampling. The decline in progesterone concentration from day 20 to day 1 before kidding was 56% in twin and 42% in single bearing goats. In single bearing goats plasma estradiol $17{\beta}$ was significantly (p<0.01) higher during prekidding days compared to twin bearing goats. The level of estradiol $17{\beta}$ was highest on the day of kidding in both the groups. The plasma prolactin level in twin bearing goats from day 10 to day 1 prepartum was higher as compared to single fetus bearing goats. However there was abrupt increase in prolactin level on the day of kidding in both the groups. The plasma growth hormone levels were significantly (p<0.01) higher in twin compared to single bearing goats. On the day of kidding growth hormone levels were significantly (p<0.01) higher in twin as compared to single bearing goats (1.40 vs. 0.95 ng/ml). In twin bearing goats plasma cortisol values from day 5 till the day of kidding remained elevated and the levels on the day of kidding was significantly highest in both the groups. The levels of triiodothyronine ($T_3$) were significantly higher (p<0.01) during all the periods of sampling in single compared to twin bearing goats. Plasma thyroxine ($T_4$) was significantly (p<0.01) lower in twin compared to single bearing goats. In single bearing goats plasma insulin levels were significantly (p<0.01) higher than twin bearing goats during prepartum period however during post partum period the levels in both the groups remained similar. It can be concluded that number of fetuses is having significant influence on the hormone profile during periparturient period.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.189-197
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• 2006

Twenty small-scale farms of two villages (A and B) were surveyed to identify the feeding traits, milk productivity and nutritional status of lactating cattle and buffalo in Terai, Nepal. Constituents and dry matter (DM) of feed supplied, body condition score (BCS), heart girth (HG), bodyweight (BW), milk yield (MY) and plasma metabolites were obtained in the pasture-sufficient, pasture-decreasing and fodder-shortage periods. Milk yield of 305-day lactation was estimated by the daily MY. The supplies of rice straw and native grass were lower and higher in the pasture-sufficient period than in the other periods, respectively (5.5 kg/day vs. 9.8 kg/day and 3.2 kg/day vs. 0.4 kg/day, respectively, p<0.01). The roughage-supplement rates of the animals were higher in village A than in village B (5.0 vs. 2.2 in cattle and 9.3 vs. 1.8 in buffalo, p<0.01). The variance of feed constituents among the periods and between the villages induced different supplies of CP, NDF and TDN. The concentrations of CP and TDN in the cattle feed were higher in the pasture-sufficient period than in the other periods (9.1% vs. 7.3% and 57.4% vs. 51.0%, respectively, p<0.01). The supplies of CP for cattle and buffalo, and of TDN for buffalo were lower in village A than in village B (7.5% vs. 8.7% and 6.6% vs. 9.1% [p<0.01], and 53.1% vs. 56.2% [p<0.05], respectively). The BCS, HG and BW of the animals were lower in village A than in village B (2.51 vs. 2.86, 156 cm vs. 170 cm and 300 kg vs. 318 kg, respectively in cattle, 2.83 vs. 4.00, 186 cm vs. 216 cm and 429 kg vs. 531 kg, respectively in buffalo, p<0.01). The cattle yielded more milk in the pasture-sufficient period than in the other periods (7.9 liters/day vs. 6.6 liters/day, p<0.01). The 305-day MY of cattle that calved in the fodder-shortage period was lower than that of cattle that calved in the other periods (1,900 liters vs. 2,251 liters, p<0.01). The MYs of cattle and buffalo were lower in village A than in village B (6.2 liters/day vs. 8.1 liters/day and 3.7 liters/day vs. 7.7 liters/day, respectively, p<0.01). The 305-day MY of cattle was lower in village A than in village B (1,935 liters vs. 2,409 liters, p<0.01). The concentrations of plasma albumin and urea nitrogen in cattle were lower in village A than in village B (3.2 g/dl vs. 3.4 g/dl [p<0.01] and 7.4 mg/dl vs. 10.2 mg/dl [p<0.05], respectively). The different supplies of CP, NDF and TDN among the periods and between the villages might have affected MY and nutritional status in cattle and buffalo. It was likely that the lower supplies of CP and TDN for cattle that calved in the fodder-shortage period and in village A lowered the 305-day MY of cattle.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.127-134
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• 1989

Several growth characteristics of two ornamental tobacco species, Nicotiana sanderae and N. affinis, were investigated in this study. Also effect of temperature and daylength on the flowering of the tobacco plants were evaluated to obtain basic information on breeding and cultivation. 1. The plants were great in high temperature-long day at the early stage and in low temperature-short day at the late stage of plant growth, for both Nicotana species. At the early growth stage the leaf length N. sanderae was great in high temperature-long day, and that of N. affinis was great in high temperature-short day period, while at the late stage of the plant growth the leaf lengths were more significantly effected by the temperature rather than daylength. Leaf width and leaf shape index were less sensitive to the conditions. 2. For both of the species, the total number of tobacco leaves not much influenced by the temperature and daylength. 3. There were no significant differences for budding and flowering period between the two species, both of which were sensitive to temperature and daylength with more influence by daylength than temperature. 4. Number of floral stalks, number of flower and flowering period were not much influenced by temperature and daylength; however, N. affinis had 2 more floral stalks, 31 more flowers, and 6 day longer flowering period than N. sanderae.

• Journal of Bio-Environment Control
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• v.12 no.1
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• pp.1-6
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• 2003

This study was conducted under the condition of greenhouse to investigate the relationships between the period of long day (LD) treatment before short day treatment, the dry matter production and flower quality of cut chrysanthemum (Indicum group) cv. Reagan Improved at Wagenigen University in the Netherlands. Rooted cuttings of chrysanthemum (Indicum group) cv. Reagan Improved were transplanted on 6th, 13th, loth of September and all of them were treated with short-days (SD) on 21th September. The periods from planting until final harvest were 70, 77, 84 days after being planted for 1, 2, and 3 week-LD period, respectively. The time of flower initiation was similar in all treatments. The number of flowers per plant was greater in the plot of 3 week-LD period than that in the plot of 1 or 2 week-LD period. The fresh weight and dry weight of flowers also increased more in the plot of 3 week-LD period than that in the 1 week-LD period by 4g and 0.4g, respectively. The final dry matter production ($g{\cdot}m$^{-2}$ ) was greater in the treatment of 3 week-LD period than 1 or 2week-LD period. In this study, LD period before short day treatment did not affect the time of flower initiation and flower quality. As a result, 3 week-LD period before short day treatment was strongly recommanded for producing high quality cut flowers of greenhouse-grown chrysanthemum.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.4
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• pp.324-331
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• 2001

The present study was aimed to investigate the effects of latency period on alveolar ridge distraction using the intraoral distraction device. Nine adult mongrel dogs of either sex, weighing about 15kg, were used. They were divided into 3-day, 5-day, and 7-day groups according to the latency period. The left upper and lower premolars and first molars were extracted. Twelve weeks after the extraction, an osteotomy was performed and the distraction device was applied. After the latency period, the distraction was applied at a rate of 1.2mm for 8 days. The distraction device was left in place for 2 weeks to allow consolidation and was then removed. The animals were sacrified at 8 weeks after completion of distraction and were examined macroscopically, radiographically, and histologically. After completion of the distraction, the alveolar crest protruded prominently, showing the vertical augmentation of the alveolar bone. Soft tissues were broken down after the 6th day of distraction in 3-day latency group, and premature union occurred on the 7th day of distraction in the 7-day latency group. The average distance was $9.40{\pm}0.3mm$ in 3-day latency group, $9.35{\pm}0.1mm$ in 5-day latency group, and $8.85{\pm}0.1mm$ in 7-day latency group. In the radiograph taken at 8 weeks after distraction, there was slight bone resorption around the medial and distal edges of the alveolar bone segment, and a new bone deposition was observed in the neighboring alveolar crest area in all groups. Fibrous tissues were present in a part of the buccal cortical bone area of the distraction gap, and the woven and lamellar bones were observed in the distracted gap. There were bony bridges in the distraction gap in all animals examined. These results suggest that optimal time of latency period on alveolar ridge distraction using the intraoral distraction device is about 5 days in dogs, and about 7days in human beings.