• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6B
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• pp.579-587
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• 2010

The mid-range streamflow forecast was performed using NWP(Numerical Weather Prediction) provided by KMA. The NWP consists of RDAPS for 48-hour forecast and GDAPS for 240-hour forecast. To enhance the accuracy of the NWP, QPM to downscale the original NWP and Quantile Mapping to adjust the systematic biases were applied to the original NWP output. The applicability of the suggested streamflow prediction system which was verified in Geum River basin. In the system, the streamflow simulation was computed through the long-term continuous SSARR model with the rainfall prediction input transform to the format required by SSARR. The RQPM of the 2-day rainfall prediction results for the period of Jan. 1~Jun. 20, 2006, showed reasonable predictability that the total RQPM precipitation amounts to 89.7% of the observed precipitation. The streamflow forecast associated with 2-day RQPM followed the observed hydrograph pattern with high accuracy even though there occurred missing forecast and false alarm in some rainfall events. However, predictability decrease in downstream station, e.g. Gyuam was found because of the difficulties in parameter calibration of rainfall-runoff model for controlled streamflow and reliability deduction of rating curve at gauge station with large cross section area. The 10-day precipitation prediction using GQPM shows significantly underestimation for the peak and total amounts, which affects streamflow prediction clearly. The improvement of GDAPS forecast using post-processing seems to have limitation and there needs efforts of stabilization or reform for the original NWP.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.83-93
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• 2024

Purpose: Since the start of the coronavirus disease 2019 (COVID-19) pandemic, various variants of concern have emerged. We divided the representative COVID-19 mutation period into four waves and aimed to analyze the clinical and laboratory features of children with COVID-19 from pre-mutation wave to the middle of omicron wave. Methods: We retrospectively reviewed the medical records of hospitalized patients aged ≤19 years with laboratory confirmed COVID-19. Clinical and laboratory findings during pre-mutation (February 1st 2020 to September 30th 2020), alpha/beta (October 1st 2020 to May 31st 2021), delta (June 1st 2021 to October 31st 2021), and omicron (November 1st 2021 to May 31st 2022) waves were compared. Results: Among total 827 patients, 163 (19.7%) were asymptomatic, and the frequency of fever and cough was 320 (38.7%) and 399 (48.2%), respectively. The proportion of fever ≥38.5℃ was observed to be high during the omicron wave in the age group under 12 years. Lymphopenia was observed highly in the omicron wave in the age group under 12 years, and in the delta wave in the age group older than 12 years. Neutropenia was highly observed in the delta wave in the 0-4 years age group. Conclusions: There were distinct characteristics during all epidemic waves of COVID-19. Children with COVID-19 had more frequent persistent fever during delta wave and children during the omicron wave had a higher peak fever.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.3
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• pp.66-73
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• 2024

Stay-cable is one of the most important load carrying members in cable-stayed bridges. Monitoring structural integrity of stay-cables is crucial for evaluating the structural condition of the cable-stayed bridge. For stay-cables, tension and damping ratio are estimated based on modal properties as a measure of structural integrity. Since the monitoring system continuously measures the vibration for the long-term period, data acquisition systems should be stable and power-efficiency as the hardware system. In addition, massive signals from the data acquisition systems are continuously generated, so that automated analysis system should be indispensable. In order to fulfill these purpose simultaneously, this study presents an autonomous cable monitoring system based on domain-knowledge using IoT for continuous cable monitoring systems of cable-stayed bridges. An IoT system was developed to provide effective and power-efficient data acquisition and on-board processing capability for Edge-computing. Automated peak-picking algorithm using domain knowledge was embedded to the IoT system in order to analyze massive data from continuous monitoring automatically and reliably. To evaluate its operational performance in real fields, the developed autonomous monitoring system has been installed on a cable-stayed bridge in Korea. The operational performance are confirmed and validated by comparing with the existing system in terms of data transmission rates, accuracy and efficiency of tension estimation.

• Korean Journal of Ecology and Environment
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• v.57 no.2
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• pp.61-74
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• 2024

Daemadeung, located in the estuary of the Nakdong River, is formed by sand dunes and possesses well-developed intertidal flats. This study aimed to investigate the habitat of benthic microalgae, photosynthetic pigments, and photosynthetic efficiency in the intertidal flats of Daemadeung from January to December 2011. The inorganic nitrogen content in the sediment pore water was primarily composed of ammonium, while nitrate + nitrite was dominant in the upper layer water. The concentration of chlorophyll a and fucoxanthin in the sediment surface was significantly higher than the mean of all the sediment layer. The average Fv/Fm of benthic microalgae during the entire survey period was 0.52±0.03, with the highest value (0.61±0.08) observed in February. The rETR_max showed a seasonal trend, being high from spring to early autumn (April to October) and low from winter to early spring (January to March, November, December), with the highest value (153.05±2.30 µmol electrons m^-2 s^-1) in July and the lowest (38.49±5.17 µmol electrons m^-2 s^-1) in January. The average Fv/Fm of diurnal microalgae was 0.48±0.03, with the highest value (0.61±0.08) observed at noon. The rETR_max showed a highest peak at noon (54.24±11.35 µmol electrons m^-2 s^-1) and reached its lowest point at 16:00 (26.17±4.75 µmol electrons m^-2 s^-1). These findings suggest that the productivity of benthic microalgae varies significantly depending on the survey time and sediment depth. Therefore, to quantify the productivity of benthic microalgae using Diving-PAM, surveys should be conducted based on tidal conditions, and simultaneous pigment analysis of sediment layers should also be performed.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.181-204
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• 1974

The study has been carried out to investigate the occurrence, damage, host range, transmission and control of rice stripe virus in Korea since 1965. 1 Disease occur「once and damage : The virus infection during the seedling stage ranged from 1.3 to $8\%$. More symptom expression was found in regrowth of clipped rice than infected intact plants, and the greater infection took place in early seasonal culture than in ordinary seasonal culture. A higher incidence of the disease was found on the rows close to the bank, and gradually decreased toward the centre of the rice paddy. Disease occurrence and plant maturity was highly correlated in that the most japonica rice types were diseased when they were inoculated within 3 to 7 leaf stage, and$50\%$, $20\%$ and no diseaseb were found if they were inoculated at 9, 11 and 13 leaf stages, respectively. Symptom expression required 7-15 days when the plants were inoculated during 3-7 leaf stages, while it was 15-30days in the plants inoculated during 9-15 leaf stages. On Tongil variety the per cent disease was relatively higher when the plants were infected within 1.5-5 leaf stages than those at 9 leaf stage, and no disease was found on the plants infected after 15 leaf stage. The disease resulted in lowered growth rates, maturity and sterility of Tongil variety although the variety is known as tolerant to the virus. 2. Host range: Thirty five species of crops, pasture grasses and weeds were tested for their susceptibility to the virus. Twenty one out of 35 species tested were found to be susceptible. and 3 of them, Cyperus amuricus Maximowics var. laxus, Purcereus sanguinolentus Nees and Eriocaulon robustius Makino, were found as new hosts of the virus. 3. Transmission: The vector of the virus, Laodelphax striatellus, produces 5 generations a year. The peak of second generation adults occurred at June 20th and those of third was at about July 30th in Suweon area. In Jinju area the peak of second generation adult proceeded the peak at Suweon by 5-7 days. The peaak of third generation adult was higher than the second at Jinju, but at Suweon the reverse was true. The occurrence of viruliferous Laodelphax striatellus was 10-15, 9, 17, 8 and about $10\%$ from overwintered nymph, 1st generation nymph, 2nd generation adult, End generation nymph and the remaining generations, respectively. More viruliferous L. striatellus were found in the southern area than in the central area of Korea. The occurrence of viruliferous L. striatellus depended on the circumstances of the year. The per cent viruliferous vectors gin 2nd and 3rd generation adult, however, was consistantly higher than that of other generations. Matings of viruliferous L. striatellus resulted in $90\%$ viruliferous progenies, and the 3rd, 4th and 5th instars of the vector had higher infectiviey than the rest of the vector stages. The virus acquisition rate of non-viruliferous L. striatellus was $7-9\%$, These viruliferous L. striatellus, however, could not transmit the virus for more than 3 serial times. The optimum temperature for the transmission of the viru3 was $25-30^{\circ}C$, while rare transmission occurred when the temperature was below $15^{\circ}C$. The per cent of L. striatellus parasitization by Haplogonatopus atratus were $5-48\%$ during the period from June to the end of August, and the maximum parasitization was $32-48\%$ at around July 10. 4. Control: 1) Cultural practices; The deeper the depth of transplanting more the disease occurrence was found. The higher infection rate, $1.5-3.5\%$, was observed during the late stages of seedling beds, and the rate became lower, $1.0-2.0\%$, in the early period of paddy field in southern area. Early transplanting resulted in more infection than early seasonal culture, and the ordinary seasonal culture showed the lowest infection. The disease also was favored by earlier transplanting even under tile ordinary seasonal culture. The higher the nitrogen fertilizer level the more the disease occurrence was found in the paddy field. 2) Resistant varieties; Tongil varieties shelved the resistant reaction to the virus in greenhouse tests. In the tests for resistance on 955 varieties most japonica types shelved susceptible reactions, while the resistant varieties were found mostly from introduced varietal groups. 3) Chemical control; Earlier applications of chemicals, Disyston and Diazinon, showed better results when the test was made 4 days after inoculation in the greenhouse even though none of the insecticides shelved the complete control of the disease. Three serial applications of chemicals on June 14, June 20 and June 28 showed bettor results than one or two applications at any other dates under field conditions.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.52-64
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• 2015

This research traced the characteristics of the semantic landscape, construction intent, landscape composition, and geomantic conditions of the area subject to the research based on the research methods of 'field investigation, document studies, and interviews,' centering around the entire area of Gokseong Hamheo-pavilion (Jeonnam Tangible Cultural Assets No. 160). The result of the research, specifically revealing the forms and methods by which the reciprocal view of nature and landscape composition appearing in the landscape of the entire area of Hamheo-pavilion, as part of the analysis and interpretation over the view-based construction characteristics and position of the entire area of Gokseong Hamheo-pavilion, can be summarized as follows. First, Hamheo-pavilion is a pavilion built as a resting area and as a venue for educational activities in 1543 in the nearby areas after Gwang-hyeon Sim founded Gunjichon-jeongsa for educational activities and dwelling purposes at Gunchon at the 30th year of King Jungjong. Gunchon, where Hamheo-pavilion and Gunjichon-jeongsa is located, exhibits the typical form having water in the front, facing Sunja-river(present Seomjin-river), and a mountain in the back side. Dongak-mountain, which is a guardian mountain, is in a snail-type form where cows leisurely ruminate and lie on the riverside, and the Hamheo-pavilion area is said to be an area bordering on one's way of enjoying peace and richness as it is a place with plentiful grass bushes available for cows to ruminate and lie down while sheppards may leisurely play their flutes at the riverside. The back hill of Hamheo-pavilion is a blood vessel that enters the water into the underwater palace of the turtle, and the building sitting on the turtle's back is Hamheo-pavilion, and the Guam-jodae(龜巖釣臺) and lava on the southern side below the cliff can be interpreted to be the underwater fairly land wanted by the turtle.6) Second, Hamheo-pavilion is the scenery viewpoint of Sungang-Cheongpung (3rd Scenery) and Seolsan-Nakjo(雪山落照, 9th Scenery) among the eight sceneries of Gokseong, while also the scenery viewpoint of Hamheo-Sunja(2nd Scenery) and Cheonma-Gwiam(天馬歸岩, 3rd Scenery) among the eight sceneries of Ipmyeon. On the other hand, the pavilion is reproduced through the aesthetics of bends through sensible penetration and transcendental landscape viewed based on the Confucian-topos and ethics as the four bends among the five bends of Sunja-river arranged in the 'Santaegeuk(山太極) and Sutaeguek(水太極, formation of the yin-yang symbol by the mountain and water)' form, which is alike the connection of yin and yang. In particular, when based on the description over Mujinjeong (3rd Bend), Hoyeonjeong(4th Bend), andHapgangjeong(2nd Bend) among the five bends of Sunja-river in the records of Bibyeonsainbangan-jido(duringthe 18th century) and Okgwahyeonji(1788), the scenery of the five bends of Sunja-river allow to glimpse into its reputation as an attraction-type connected scenery in the latter period of the Joseon era, instead of only being perceived of its place identity embracing the fairyland world by crossing in and out of the world of this world and nirvana. Third, Hamheo-pavilion, which exhibits exquisite aesthetics of vacancy, is where the 'forest landscape composed of old big trees such as oak trees, oriental oak trees, and pine trees,' 'rock landscape such as Guam-jodae, lava, and layered rocks' and 'cultural landscape of Gunchon village' is spread close by. In the middle, it has a mountain scenery composed of Sunja-river, Masan-peak, and Gori-peak, and it is a place where the scenery by Gori-peak, Masan-peak, Mudeung-mountain, and Seol-mountain is spread and open in $180^{\circ}$ from the east to west. Mangseo-jae, the sarangchae (men's room)of Gunjichon-jeongsa, means a 'house observing Seoseok-mountain,' which has realized the diverse view-oriented intent, such as by allowing to look up Seol-mountain or Mudeung-mountain, which are back mountains behind the front mountain, through landscape configuration. Fourth, the private home, place for educational activities, pavilion, memorial room, and graveyard of Gunji-village, where the existence and ideal is connected, is a semantic connected scenery relating to the life cycle of the gentry linking 'formation - abundance - transcendence - regression.' In particular, based on the fact that the descriptions over reciprocal views of nature regarding an easy and comfortable life and appreciations for a picturesque scene of the areas nearby Sunja-river composes most of the poetic phrases relating to Hamheo-pavilion, it can be known that Hamheo-pavilion is expressed as the key to the idea of 'understanding how to be satisfied while maintaining one's positon with a comfortable mind' and 'returning to nature,' while also being expressed of its pedantic character as a place for reclusion for training one's mind and training others through metaphysical semantic scenery.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.479-492
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• 1997

Background : Isoniazid(INH) and rifampicin(RFP) are potent antituberculous drugs which have made tuberculous disease become decreasing. In Korea, prescribed doses of INH and RFP have been different from those recommended by American Thoracic Society. In fact they were determined by clinical experience rather than by scientific basis. Even there has been. few reports about pharmacokintic parameters of INH and RFP in healthy Koreans. Method : Oral pharmacokinetics of INH were studied in 22 healthy native Koreans after administration of 300 mg and 400mg of INH to each same person successively at least 2 weeks apart. After an overnight fast, subjects received medication and blood samples were drawn at scheduled times over a 24-hour period. Urine collection was also done for 24 hours. Pharmacokinetics of RFP were studied in 20 subjects in a same fashion with 450mg and 600mg of RFP. Plasma and urinary concentrations of INH and RFP were determined by high-performance liquid chromatography(HPLC). Results : Time to reach peak serum concentration (Tmax) of INH was $1.05{\pm}0.34\;hrs$ at 300mg dose and $0.98{\pm}0.59\;hrs$ at 400mg dose. Half-life was $2.49{\pm}0.88\;hrs$ and $2.80{\pm}0.75\;hrs$, respectively. They were not different significantly(p > 0.05). Peak serum concentration(Cmax) after administration of 400mg of INH was $7.14{\pm}1.95mcg/mL$ which was significantly higher than Cmax ($4.37{\pm}1.28mcg/mL$) by 300mg of INH(p < 0.01). Total clearance(CLtot) of INH at 300mg dose was $26.76{\pm}11.80mL/hr$. At 400mg dose it was $21.09{\pm}8.31mL/hr$ which was significantly lower(p < 0.01) than by 300mg dose. While renal clearance(CLr) was not different among two groups, nonrenal clearance(CLnr) at 400mg dose ($18.18{\pm}8.36mL/hr$) was significantly lower than CLnr ($23.71{\pm}11.52mL/hr$) by 300mg dose(p < 0.01). Tmax of RFP was $1.11{\pm}0.41\;hrs$ at 450mg dose and $1.15{\pm}0.43\;hrs$ at 600mg dose. Half-life was $4.20{\pm}0.73\;hrs$ and $4.95{\pm}2.25\;hrs$, respectively. They were not different significantly(p > 0.05). Cmax after administration of 600mg of RFP was $13.61{\pm}3.43mcg/mL$ which was significantly higher than Cmax($10.12{\pm}2.25mcg/mL$) by 450mg of RFP(p < 0.01). CLtot of RFP at 450mg dose was $7.60{\pm}1.34mL/hr$. At 600mg dose it was $7.05{\pm}1.20mL/hr$ which was significantly lower(p < 0.05) than by 450mg dose. While CLr was not different among two groups, CLnr at 600 mg dose($5.36{\pm}1.20mL/hr$) was significantly lower than CLnr($6.19{\pm}1.56mL/hr$) by 450mg dose(p < 0.01). Conclusion : Considering Cmax and CLnr, 300mg, of INH and 450mg RFP might be sufficient doses for the treatment of tuberculosis in Koreans. But it remains to be clarified in the patients with tuberculosis.

• The Korean Journal of Malacology
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• v.23 no.2
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• pp.189-198
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• 2007

The reproductive cycle, egg capsules in the egg-mass, first sexual maturity, and sex ratio of the bladder moon, Glossaulax didyma ($R\ddot{o}ding$) were investigated. The gastropods collected from the intertidal zone of Biin Bay, Seocheon, Korea were studied by using histological analysis and morphometric data. The gonadosomatic index (GSI) of females and males began to increase in March and reached maximum in May. Then their values sharply decreased from late in May to August due to spawning. The condition index (CI) began to increase in February and reached maximum in May, then gradually declined in the spawning period. The CI calculated for determination of the spawning period was coincided with changes in the GSI and gonadal phases. Spawning occurred between late in May to August in females and early in May to August in males. Spawning peak was observed between July and August when the seawater temperature rose to 19 $^{\circ}C$. Reproductive cycle with the gonadal development phases of this species can be divided into five successive stages in females and four in males: in females, early active stage (December to February), late active stage (February to March), ripe stage (April recovery stage (August to November); in males, active stage (December to March), ripe stage (March to July), copulation stage (early May to August), and recovery stage (August to January). Fully matured oocytes were approximately 250-270 ${\mu}m$ in size. The egg-mass was a hat in shape, and a number of egg capsules were found in an egg-mass. An egg capsule was 0.53-0.57 mm in size. An embryo (veliger larva) hatched from an egg capsule. Percentage of first sexual maturity in females and males were over 50% for individuals that are 40.1-45.0 mm in shell radius, and 100% for those that are over 45.1 mm. The sex ratio of female to male was significantly different from 1:1 $(x^2\;=\;57.22,\;p\;<\;0.05)$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.374-383
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• 2010

Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a ground-based polarimetric scatterometer has advantages of monitoring crop conditions continuously with full polarization and different frequencies. Kim et al. (2009) have measured backscattering coefficients of paddy rice using L-, C-, X-band scatterometer system with full polarization and various angles during the rice growth period and have revealed the necessity of near-continuous automatic measurement to eliminate the difficulties, inaccuracy and sparseness of data acquisitions arising from manual operation of the system. In this study, we constructed an X-band automatic scatterometer system, analyzed scattering characteristics of paddy rice from X-band scatterometer data and estimated rice growth parameter using backscattering coefficients in X-band. The system was installed inside a shelter in an experimental paddy field at the National Academy of Agricultural Science (NAAS) before rice transplanting. The scatterometer system consists of X-band antennas, HP8720D vector network analyzer, RF cables and personal computer that controls frequency, polarization and data storage. This system using automatically measures fully-polarimetric backscattering coefficients of rice crop every 10 minutes. The backscattering coefficients were calculated from the measured data at a fixed incidence angle of $45^{\circ}$ and with full polarization (HH, VV, HV, VH) by applying the radar equation and compared with rice growth data such as plant height, stem number, fresh dry weight and Leaf Area Index (LAI) that were collected at the same time of each rice growth parameter. We examined the temporal behaviour of the backscattering coefficients of the rice crop at X-band during rice growth period. The HH-, VV-polarization backscattering coefficients steadily increased toward panicle initiation stage, thereafter decreased and again increased in early-September. We analyzed the relationships between backscattering coefficients in X-band and plant parameters and predicted the rice growth parameters using backscattering coefficients. It was confirmed that X-band is sensitive to grain maturity at near harvesting season.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.161-168
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• 2014

This study aimed to investigate dietary concentrate:forage ratios (C:F) and undegraded dietary protein (UDP) on nitrogen balance and urinary excretion of purine derivatives (PD) in lambs. Four Dorper${\times}$thin-tailed Han crossbred castrated lambs with $62.3{\pm}1.9$ kg body weight at 10 months of age were randomly assigned to four dietary treatments in a $2{\times}2$ factorial arrangement of two levels of C:F (40:60 and 60:40) and two levels of UDP (35% and 50% of CP), according to a complete $4{\times}4$ Latin-square design. Each experimental period lasted for 19 d. After a 7-d adaptation period, lambs were moved into individual metabolism crates for 12 d including 7 d of adaption and 5 d of metabolism trial. During the metabolism trial, total urine was collected for 24 h and spot urine samples were also collected at different times. Urinary PD was measured using a colorimetric method and creatinine was measured using an automated analyzer. Intake of dry matter (DM) (p<0.01) and organic matter (OM) (p<0.01) increased as the level of UDP decreased. Fecal N was not affected by dietary treatment (p>0.05) while urinary N increased as the level of UDP decreased (p<0.05), but decreased as dietary C:F increased (p<0.05). Nitrogen retention increased as dietary C:F increased (p<0.05). As dietary C:F increased, urinary excretion of PD increased (p<0.05), but was not affected by dietary UDP (p>0.05) or interaction between dietary treatments (p>0.05). Daily excretion of creatinine was not affected by dietary treatments (p<0.05), with an average value of $0.334{\times}0.005$ mmol/kg $BW^{0.75}$. A linear correlation was found between total PD excretion and PDC index ($R^2$ = 0.93). Concentrations of creatinine and PDC index in spot urine were unaffected by sampling time (p>0.05) and a good correlation was found between the PDC index (average value of three times) of spot urine and daily excretion of PD ($R^2$ = 0.88). These results suggest that for animals fed ad libitum, the PDC index in spot urine is effective to predict daily excretion of PD. In order to improve the accuracy of the spot sampling technique, an appropriate lag phase between the time of feeding and sampling should be determined so that the sampling time can coincide with the peak concentration of PD in the urine.