• Journal of the Korean Geographical Society
• /
• v.36 no.4
• /
• pp.474-482
• /
• 2001

The purpose of this study is to investigate the formation and development processes of beach resort by fabric construction in a island environment. The results are as follows. (1) The research area(Tong-ri beach, Bokil-myon, Chollanam-do)has been transformed to belch by sedimentary environmental change since latter half of 1800's. (2) The mean slope of beach face is 0.96°, and the difference of attitude between beach and mud flat face is 75cm. (3) The mean particle size of beach surface sediment is 3.53$\Phi$. This value is very finer than that of any other beach in Korea peninsula. But its value is coarser than that of mud flat surface sediment. (4) The particle size distribution of core sediment is become changed to fine particle in 70cm depth. This value is corresponded to difference of altitude between beach face and mud flat face. (5) The analysis of aerial photographs after 1970 indicates that sedimentation process was not brisked since 1970's. Consequently, the research ares has been developed by sedimentary environmental change for sea-level rise effect and wave height energy rise effect.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.54 no.5
• /
• pp.133-137
• /
• 2017

The purpose of this study was to validate for GATE (Geant4 Application for Tomographic Emission) simulation by comparing the results of GATE simulation and experiment in real SPECT system. Futhermore, we want to prove that it is possible that the quantitative research of gamma camera/SPECT imaging for therapeutic radio isotope by using GATE simulation. In this study, the SPECT system on simulation referred to the parameters of Stream-R Forte version 1.2 (Philips Medical System, Best and Heerlen, Netherlands). To understand the I-131 image of gamma camera/SPECT system, we acquired the energy spectrum and measured the full width at half maximum (FWHM) which comes from line spread function (LSF) with and without scatter material in real SPECT system. And to compare with experiment, we also measured the FWHM and acquired the energy spectrum without scatter material in GATE simulation. As a result, without scatter material, the energy peak was almost same location, which are located nearby 364 keV, and other spectrum factors are same tendency in both cases. The FWHM was increased by increasing the distance of source to detector, and the error rate was approximately 3.8%. When we used the line source with scatter material, energy spectrum also indicated similar tendency in both cases. As you confirmed earlier, GATE simulation included real instrument and radioisotope characters for therapeutic radioisotope. Therefore this result that it was possible that various quantitative study for therapeutic radioisotope imaging in gamma camera/SPECT using GATE simulation.

• Korean Journal of Poultry Science
• /
• v.19 no.4
• /
• pp.177-185
• /
• 1992

This study was carried out to investigate the relationship between frequency of soft and broken eggs and the economic traits for colored laying hens using the data sampled 7 times in Korea from 1985 to 1991. In addition, the correlation coefficients of frequency of soft and broken eggs on the economic traits for colored laying hens in order to decrease the frequency of soft and broken eggs were studied. The results obtained were summarized as follows ： 1. For colored laying hens, mean of the sexual maturity(SM) was 163.6 days, hen-day egg Production(HDEP) was 79.49％, hen-housed egg Production(HHEP) was 272.9 eggs, egg weight (EW) was 62.69g and the frequency of soft and broken eggs was 1.363％ during 18∼72wks. For white laying hens, SM was 157.2 days, HDEP was 77.87％, HHEP was 265.1 eggs, EW was 60. 26g and the frequency of soft and broken eggs (FSBE) was 1.174％ during 18∼72wks. 2. Statistical significances were observed in laying viability, SM, HDEP, FR, BW and FSBE during 18 ∼72wks and 18 ∼78wks by year for colored laying hens. 3. Sexual maturity was shortened from 168.5 days to 155.9 days. FSBE decreased from 1.4∼l.69％ to 0.94∼o.89％ during 18∼72wks, and HDEP was increased from 74.5∼75.1％ to 77.8∼80.6％, HHEP was increased to 302.0∼304.6 eggs and FSBE was increased from 1.54∼2.02％ to 0.98％ during 18∼78wks in colored laying hens. 4. Estimate of correlation coefficients between FSBE and trait of SM, EW, 72 wks BW were 0.3985, 0.1072, 0.4225, and those of HDEP, HHEP, FR were -0.5662, -2896, -0.245 during 18∼72wks In colored laying hens, respectively. 5. Estimate of correlation coefficients between FSBE and traits of SM, EW, 78wks BW were 0.3791, 0.1171, 0.4609, and those of HDEP, HHEP, FR were -0.5041, -0.2372, -0.2421 during 18∼78wks in colored laying hens, respectively.

• 한국해양학회지
• /
• v.30 no.5
• /
• pp.403-412
• /
• 1995

The present study was performed to determine th growth and production of Mactra veneriformis on the Songdo tidal flat off Inchon. west coast of Korea. Monthly samples were collected from Marc 1989 to September 1990. The size distributions of shell length showed unimodal patterns from March to August 1989. The binodal pattern after September 1989 indicated a recruitment of young clams during this period. The density fluctuated irregularly, but showed a decreasing pattern over time on the whole. The density of the year class 1989 increased markedly after February 1990. The growth in shell length showed three phases during a year, a fast growth phase in spring, a slow growth phase in summer and autumn, and a lag phase in winter. The annual increment in shell length reduced with age. The flesh dry weight showed a peak in late spring just before the spawning period, and another peak in autumn. The length of annuli and the back-calculated flesh dry weight were used to describe the annual growth. The growth in shell length fitted to the von Bertalanffy model and the flesh dry weight to the Gompertz model. The absolute growth rate of the shell length reduced gradually with age. The year class 1985 had the highest L, and the yeat class 1986 the lowest L. The annual growth in weight showed a typical sigmoid curve. The growth rate was maximum at the age of 2 to 3. Year classes of 1984 and 1985 had higher values of W and higher absolute growth rates than those of 1986 and 1987. Maximum absolute growth rates of 1986 and 1987 year classes were recorded at younger ages than 1984 and 1985 year classes. The annual relative growth rates of length and weight decreased exponentially with age. Biomass in flesh dry weight increased till spring and thereafter decreased progressively. Maximum biomass was 134.6g m/SUP -2/ in August 1990. The biomass of 1989 yeat class occupied highest proportion in total biomass. Annual production in flesh dry weight from March 1989 to March 1990 was 67.9 g m/SUP -2/ year/SUP -1/. Cumulative production of 1989 year class was highest among all year classes, and that of year class 1984 was lowest. The production is high in spring and autumn, and very low in summer and winter.

• Journal of fish pathology
• /
• v.2 no.2
• /
• pp.53-70
• /
• 1989

An ovarian parasite, Marteilioides chungmuensis of the Pacific oyster, Crassostrea gigas has been observed on several occasions in the Pacific sector of production of this oyster species(Matsuzato et al., 1977 ; Chun, 1979). This study was carried out on the specimens collected at Hwado, Och'$\check{o}$n, and Sinchang respectively located the southern, western, and eastern coasts of Korean Peninsula from 1986 through 1988 to investigate M. chungmuensis to the Pacific oyster. Uitrastructural studies were also carried out on infected oysters, to allow detailed examination of the structure and consepuently the systematic position of this parasite. Infection rates of M. chungmuensis at Hwado and Och'$\check{o}$n oyster farms were 5.3% and 4.2% each in 1986, 6.7% and 2.8% each in 1987, but they were not found at Sinchang oyster habitat. M,. chungmuensis-infected oysters were found from June to November at Hwado and from June to October at Och'$\check{o}$n. Twenty five of three hundred oysters transplanted from Sinchang to Hwado were found infected with M. chungmuensis. Some abnormal eggs infected with M. chungmuensis are liberated through the gill together with normal mature eggs on the spawning and the rest remain necrotized after spawning season. The earliest known stages consist of a stem cell or primary cell, including a secondary cell in which ovoid haplosporosomes are found. During sporulation, 2 or 3 secondary are produced by exogenous budding from the first secondary cell and, each secondary cell evolves into a sporont upon the tertiary cell differentiation (enodogenous budding) ; then, haplosporosomes are formed in the young sporont. Internal cleavages involve the differentiation of one tricellular spore per sporont. The outermost spore cell contains membrane-bounded osmiophilic bodies : the middle and the inner, most spore cells contain high density cytoplasmic ribosomes. The mechanism of spore formation from the stem cell of M. chungmuensis is the simplest of the class Paramyxea known up to now.

• Journal of Animal Environmental Science
• /
• v.16 no.2
• /
• pp.135-142
• /
• 2010

The composting of layer manure is economical and efficiently process. In this study, the variation of composting characteristics in layer manure was investigated according to air supply capacity. The fermented compost was added in layer manure and mixed with sawdust inside composting reactors. The level of air supply capacity was varied in the range of $50{\sim}200\;{\ell}/m^3/min$. During composting the temperature variations of composting piles was different the temperatures of composting piles for T-1 ($50\;{\ell}/m^3/min$) and T-2 ($100\;{\ell}/m^3/min$) were reached at $40^{\circ}C$ and $50^{\circ}C$ within 2 days, respectively. For T-3 ($150\;{\ell}/m^3/min$) and T-4 ($200\;{\ell}/m^3/min$), their temperatures was $60^{\circ}C$ within same days and maintained during 8 days. Water contents decreased according to the air supply capacity; 8.9%, 15.4%, 18.0% and 18.6% for T-1, T-2, T-3 and T-4. The weight ratios of T-1, T-2, T-3 and T-4 were reduced to 12.8%, 15.6%, 18.1% and 17.9%, respectively. The decreasing volumetric ratios of T-1, T-2, T-3 and T-4 were 18.0%, 21.0%, 22.3% and 22.0%. The oxygen discharge concentrations during composting were 12 ppm for T-1, T-2 and 9 ppm for T-3 and T-4. After composting, fertilizer components such as total nitrogen (TN) and phosphorous pentoxide ($P_2O_5$) were examined at each air supply capacity. Nitrogen contents of the T-1, T-2, T-3 and T-4 were 0.75%, 0.74%, 0.72% and 0.64%. Also, The contents of $P_2O_5$ were 0.35%, 0.40%, 0.38% and 0.42% for T-1, T-2, T-3 and T-4.

• Korean Journal of Poultry Science
• /
• v.43 no.4
• /
• pp.229-233
• /
• 2016

This study was conducted to compare three commercially available egg testing devices for measuring egg quality. The devices used were a Laser-type (automatic), a Ultrasonic-type (automatic), and a Probe-type (manual). Fresh eggs weighing 60~68 grams were obtained from a commercial hen farm. Three trials were conducted. In Trial 1, a total of 50 eggs were successively analyzed by the three egg testing devices. In Trial 2, fresh eggs were successively analyzed by a combination of two egg testing devices. In Trial 3, a total of 600 eggs (weighing 60~68 grams) laid by same flock were selected, further divided into three sub-groups with a total of 200 eggs, and analyzed by an egg testing device. In Trials 1 and 2, no apparent difference was observed in egg weight between egg testing devices. However, albumin height was scored highest in the Ultrasonic-type egg tester followed by the Probe-type and Laser-type (Trials 1 and 2). Consequently, the Haugh unit was similarly altered. Yolk color was highest in the Laser-type egg tester followed by the Ultrasonic-type and Probe-type (Trials 1 and 2). When fresh eggs laid by a single flock were independently analyzed by three devices, egg weight did not differ, but albumin height and Haugh unit were higher (p<0.05) in the Ultrasonic-type egg tester than in the Probe-type or Laser-type testers. However, Laser-type testers produced higher (p<0.05) yolk color values than the Ultrasonic-type or Probe-type egg testers. In conclusion, the commercially available egg testing devices exhibited performance differences in measuring egg qualities, which warrants further consideration as to whether the magnitude of bias and precision between the devices could be acceptable in the egg grading system, especially when assessing eggs stored for certain durations.

• Korean Journal of Environment and Ecology
• /
• v.26 no.1
• /
• pp.57-66
• /
• 2012

This study was conducted to investigate the reproductive ecology of the Korean Mandarin Fish, Siniperca scherzeri in Seomjin River and Imjin River from April to October 2008. After have investigating the relationship between standard length (SL) and Gonadosomatic index (GSI) of Siniperca scherzeri, we can conclude that the body length of maturation was over 200mm SL in case of females and over 180mm SL in males. The GSI of the females that were from Seomjin river was the highest in April (7.43%), and gradually decreased after May (5.55%) and June (3.58%). The GSI was decreased sharply in August and indicated the lowest value in September (0.44%). The GSI of the females that were from Imjin river showed similar tendency of females' GSI from Seomjin river. The GSI of males from Imjin river was totally higher than that of females, it was 5.96% in April, and 8.03% in May. It was lowered in early June, and late June, it indicated 2.12%. In September, it was the lowest value (0.20%), and increased after October (0.54%). The result of histological study of ovary presented similar result of the study of GSI in Seomjin river and Imjin river. The ratio that fishes constitute in stomach contents of Siniperca scherzeri was 92% in Seomjin river and 90% in Imjin river. Digestion of food organisms and the ratio of unidentifiable fishes in stomach contents was fairly high, and it was 50% in Seomjin river and 72.2% in Imjin river. In the period of study, eating ratio was very low 38.3% (36 ind.) in Seomjin river and 21.8 (53 ind.) in Imjin river.

• Journal of Sericultural and Entomological Science
• /
• v.49 no.1
• /
• pp.14-17
• /
• 2007

A new silkworm variety Golden silk for spring rearing season is $F_1$ hybrid between Jam311, a Japanese race bred from introduction breeding and Jam312, a Chinese race from introduction breeding. In the local adaptability test performed at 8 local areas in spring of 2006, "Golden silk" was showed 7 percent higher in hatchability than authorized silk-worm races laval. "Golden silk" was receded higher 1.7 percent, 2.2 percent in pupation rate, best cocoon rate respectively than Chunsujam. The larval period shortened for 1.12 day even though low record to the several items including productivity than Chunsujam. "Golden silk" was showed 1,031 m, 2.97 denier in length of cocoon filament, weight of cocoon filament respectively. The concentration of Deoxynojirimycin(DNJ) was measured 4.34 mg in "Golden silk", high then to "Chunsujam"(3.81 mg). In the Paecilomyces tenuipes production ability test, the pupal weight of "Golden silk" was 1.20g.

• Korean journal of applied entomology
• /
• v.36 no.1
• /
• pp.77-82
• /
• 1997

This study was carried out to investigate the developmental characteristics and life cycle of sciarid fly (Lycoriella sp.), an important mushroom pest. The sciarid fly was reared ina growth chamber at 21$\pm$$1^{\circ}C$ and 55$\pm$5% of relative humidity with a 16h high, 8h dark cycle and Flammulina velutipes was used at diet. The egg was oval with 0.17 mm in diameter and 0.27 mm in length. Average egg period was 4 days. Body length of each instar from the 1st to 3rd was 0.7, 1.5, and 4.5, mm. respectively. Average weight of each instar was 1.9, 15.4 and 93.6 $\mu\textrm{g}$, respectively. In the 4th instar larvae, however, developmental characteristics of female and male became different by body length, weight and segment size. Body length and weight of the 4th instar female larvae were 5 mm and 162$\mu\textrm{g}$, and those of the male larvae were 3.5 mm and 90 $\mu\textrm{g}$, respectively. The larval periods of female and male were respectively 13.5 and13 days. Pupal length of female and male was 3.5 and 2.7 mm, and average weight was 136 $\mu\textrm{g}$ and 6.5$\mu\textrm{g}$, respectively. Adults were emerged from female and male pupae on 5.5 and on 5 days after pupation, respectively. Average longevity of male and female were 7 and 5 days, respectively. The weight of female was two-fold heavier than the male. After copulation, female laid approximately 130 to 150 eggs on/in the sporophore of mushroom. In conclusion, total lifespan of male and female were 29 and 28 days, respectively.