• Journal of Animal Environmental Science
• /
• v.15 no.2
• /
• pp.139-146
• /
• 2009

This study was carried out to investigate the reproductive and weaned performances in sow farms, which located in Boryeong city, Chungnam. Data surveyed a total of 10,394 litters of sow recorded from April, 2007 to March, 2008 were collected and analyzed. The results obtained were as follows; 1. The average of number of sow and farrowing rate were 314.10 sows and 78.77%, respectively. And then, there was not significant difference among seasons in number of sows, but significant difference among season was found in farrowing rate (p<0.05). 2. The average of litter size at farrowing and at initial sucking were 11.04 and 10.22 pigs, respectively. The significant differences were not all found in litter size among seasons. 3. The number of pigs, age and growth rate at weaning were 9.23 pigs, 25.77 days and 91.48%, respectively. The significant differences among seasons were not found in number of pigs and age at weaning. However, there was significant difference in growth rate at weaning (P<0.05). 4. The average of farrowing rate of sows per year, pigs from sow per year (PSY), and body weight at marketing were 2.25 times, 20.75 pigs, and 110.46 kg, respectively. The significant differences among seasons were not found in farrowing rate per year and weight at marketing, but that was found only in PSY (p<0.05), respectively.

• Journal of Preventive Medicine and Public Health
• /
• v.15 no.1
• /
• pp.153-159
• /
• 1982

A statistical study on medical students who entered certain college of medicine during 10 years ('73 to '82) was performed in order to evaluate medical educational wastage. The obtained results summerized were as follows; 1. The normal promotion rate of 10 cohorts(CI-CX) was 83.4% and 5 cohorts(CI to CV) whose members had already graduated(including dropouts) was 77.5%. 2. The mean repetition rate in 1st grade was 15.5%, in 2nd grade 5.4%, in 3rd grade 1.4% arid in 4th grade 0.6%. 3. The predicted number of repetion(spell base) which are attendance at the college in 1st grade was 31.6, in 2nd grade 28.9, in 3rd grade 18.6 and in 4th grade 22.7; 4. The total wastage of 10 cohorts was 224.8 SY, which corresponded to educational resources of 56.2 out-puts for normal demand. 5. The mean unit cost of 10 cohorts was 4.62 and the mean Input/Output ratio was 1.06.

• Water for future
• /
• v.28 no.5
• /
• pp.219-233
• /
• 1995

A non-stationary multivariate model is selected in which the mean and variance of rainfall are not temporally or spatially constant. And the rainfall prediction system is constructed which uses the recursive estimation algorithm, Kalman filter, to estimate system states and parameters of rainfall model simulataneously. The on-line, real-time, multivariate short-term, rainfall prediction for multi-stations and lead-times is carried out through the estimation of non-stationary mean and variance by the storm counter method, the normalized residual covariance and rainfall speed. The results of rainfall prediction system model agree with those generated by non-stationary multivariate model. The longer the lead time is, the larger the root mean square error becomes and the further the model efficiency decreases form 1. Thus, the accuracy of the rainfall prediction decreases as the lead time gets longer. Also it shows that the mean obtained by storm counter method constitutes the most significant part of the rainfall structure.

• Journal of Korea Water Resources Association
• /
• v.44 no.4
• /
• pp.327-338
• /
• 2011

This study examined the quantification problem of a storm shape using the concept of equivalent ellipses. The equivalent ellipses of a storm event were estimated at every time step with respect to the several thresholds of rainfall intensity, which was also examined in terms of their size and number. In addition, the average equivalent ellipse was decided, and the confidence intervals of major axis, minor axis, and rotational angle were calculated to evaluate if the average equivalent ellipse could be the representative one. As results, the following results could be derived. First of all, the number of equivalent ellipses and the size of equivalent ellipses increase as the threshold increase. Secondly, the appropriate ratio of major and minor axises of equivalent ellipse is 2 : 1. Finally, the average rotational angle estimated with respect to several threshold rainfall intensities were all found not to be statistically different from that of all representative rotational angles.

• Journal of Food Hygiene and Safety
• /
• v.16 no.3
• /
• pp.178-187
• /
• 2001

A study has been performed to estimate the average and high (90th percentile of consumers-only) daily intakes of sorbates by age-sex groups (> 3 years old) in Korea. The estimation of daily intakes was based on individual-based dietary intake data in ‘National Health and Nutrition Survey in 1998’and the contents of sorbates from samples. The estimated daily intakes (EDI) of sorbates for average consumers ranged from 0.09 mg/kg/bw/day to 0.51 mg/kg bw/day corresponding to 0.4-2.1% of acceptable daily intake (ADI). For high consumers, the range of EDI of sorbates was 3.42-14.65 mg/kg bw/day corresponding to 13.7-58.6% of ADI. Foods that contributed most to the daily intakes of sorbates for all age-sex groups were processed fish products, processed meat products, and salted floods. There was an inverse relationship between age and the consumption of sorbates for average and high consumers, whereas no marked pattern was emerged by sex categories. The intake levels of sorbates even among high consumers were below the ADI in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.12 no.1
• /
• pp.71-77
• /
• 1979

An ecological survey on the crawling activity of the Periophthalmus cantonensis in the Gum River was carried out during the period from July to October 1978. The results obtained are as follows. Distribution : From Chilsanri to Osikdo $$Density\;of\;population\;(Number/m^2):\;1.5/m^2$$ $$High\;ebb\;zone:\;2.6/m^2=56\%$$ $$Mid\;ebb\;zone:\;1.5/m^2=32\%$$ $$Low\;ebb\;gone:\;0.5/m^2=12\%$$ The percentage of the fish having established territory, then Mean body length of the fish having established territory: $86\%$ Mean body length of the transfering population : 2.16mm/sec Activity area: 10m As the fish grow there is a tendency that the individual occupy a certain area, the territory, then gradually increasing the area. When they re-aggregate, especially in high ebb zone, size difference between individuals in a group is not observed.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.5A
• /
• pp.267-275
• /
• 2003

In UMTS terminal modem uses 3 step search procedure for initial cell search, which comprises 1) slot synchronization, 2) code group identification and frame synchronization, and 3) scrambling-code identification. The performance of initial cell search procedure depends on search parameters like observation time and threshold. The purpose of this paper is to get the optimal observation time and threshold of each step for minimum mean acquisition time. In this paper we induce mean detection time of each step and mean acquisition timefrom the model of 3 step search procedure using state diagram. Also we propose initial cell search algorithm which utilize window search method against initial oscillator error, and select an appropriate observation time and threshold of each step by the analysis of simulation and induced result. It is shown that the mean acquisition time in multipath fading channel can be shorter than 500ms by using the determined observation time and threshold of each step.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.61 no.3
• /
• pp.191-195
• /
• 2016

This study was carried out to find a new corn cultivar with multiple tillers that is suitable for forage. Materials were developed at the Corn Breeding Laboratory of Chungnam National University. A total of 3,650 accessions were collected domestically and from other countries, including China. Among them, 16 CNU inbreds, tillering and non-tillering, were compared to each other in terms of stem heigh, number of tillers, fresh weight, and dry weight per plant. Of these surveyed traits, the stem heigh at tasseling stage was 140~190 cm and number of tillers per plant ranged from two to four. Fresh weight and dry weight of these lines were higher in the tillered than in the non-tillered sample.

• Smart Media Journal
• /
• v.9 no.3
• /
• pp.122-129
• /
• 2020

The possibility that an asymptotic coronavirus-19 infected person around the world is not aware of his infection and can spread it to people around him is still a very important issue in that the public is not free from anxiety and fear over the spread of the epidemic. In this paper, the K-means clustering algorithm and deep learning-based crowd aggregation were proposed to determine the possibility of contact with confirmed cases of infectious diseases. As a result of 300 iterations of all input learning images, the PSNR value was 21.51, and the final MAE value for the entire data set was 67.984. This means the average absolute error between observations and the average absolute error of fewer than 4,000 people in each CCTV scene, including the calculation of the distance and infection rate from the confirmed patient and the surrounding persons, the net group of potential patient movements, and the prediction of the infection rate.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.34 no.5
• /
• pp.515-522
• /
• 2010

The objective of this study is to investigate the air-side heat transfer characteristics of a spirally-coiled circular fin-tube heat exchanger for various geometric parameters under non-frosting conditions. The heat transfer characteristics of the heat exchanger were analyzed with respect to heat exchanger geometries, and then, the characteristics were compared with those of rectangular-plate fin-tube heat exchangers with discrete fins. The heat transfer coefficient increased with a decrease in the number of tube rows and an increase in the fin pitch. The optimum length of the L-foot was 2.7 mm. In addition, the heat transfer rate increased with a decrease in the tube pitch and the tube thickness. The heat transfer coefficient of the spirally-coiled circular fin-tube heat exchanger was 24.3% higher than that of the rectangular-plate fin-tube heat exchanger.