• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.118-119
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• 2001

3차원 디스플레이 시스템에 대한 연구는 입체 영상이 높은 해상도와 넓은 시야각을 갖도록 하기 위하여 다양한 방식으로 활발히 진행되고 있다. 1908년 Lippmann에 의하여 제안된 Integral photography(IP)는 특별한 안경이 필요하지 않고 연속적인 시점을 제공한다는 장점을 갖고 있다. 제안된 당시에는 기록 및 재생 매체로 사진 건판을 사용하여 동영상의 재생이 불가능하였지만, 최근 사진 건판 대신 CCD 카메라와 LCD 패널을 기록 및 재생 매체로 사용함으로써 동영상이 가능한 IP 시스템이 제안되었다. (중략)

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1905-1908
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• 2002

In this paper, we analyze the natural processing delay of OFDM systems and proposed two modified unctional blocks to decrease about 25% of the total delay. e evaluate BER performance of the proposed scheme to e compared with that of classical one to confirm same performance between them.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1903-1908
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• 2004

A preconditioned numerical method for gas-liquid two-phase flows is applied to solve cavitating flow. The present method employs a finite-difference dual time-stepping integration procedure and the MUSCLTVD scheme. A homogeneous equilibrium cavitation model is used. The present density-based numerical method permits simple treatment of the whole gas-liquid two-phase flow field, including wave propagation, large density changes and incompressible flow characteristics at low Mach number. Some internal flows such as convergent-divergent nozzles are computed using this method. Comparisons of predicted and experimental results are provided and discussed.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.7 no.1
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• pp.110-119
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• 1996

Heller recognized the children exhibiting developmental regression after normal period of development and proposed the term 'dementia' infanilis for the condition and reported it 1908. But the foolowing studies were insufficient, the diagnostic concept was not definded, and various names such as dementia infantilis, Heller's syndrome, disintegrative psychosis and childhood disintegrative disorder have been used for that condition. Recently the term childhood disintegrative disorder fir that condition was proposed as independent disease entity by DSM-IV and ICD-10, and the interset in that condition is increasing now. But because of insufficient previous studies on that condition, the definite concept, the characteristics, the relationship with autism or other similar conditions, the treatment and prognosis of that condition are not clear by this time, therefore we have not seen the official report on the condition in our country. These authors experienced a case considered as childhood disintegrative disorder and report it with the review of literatures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1908-1914
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• 2013

In the present study, the levels of phenolic compounds and flavonoids, as well as activities of radical scavenging (DPPH and ABTS radical scavenging activity) and anti-obesity were assessed with cold water (CLC), hot water (CLH), and methanolic (CLM) extracts of Curcuma longa L. (turmeric). Our results showed that the phenolic compounds of CLC, CLH and CLM were $3.68{\pm}0.80%$, $3.94{\pm}0.74%$ and $9.01{\pm}0.73%$, respectively. The DPPH and ABTS radical scavenging activities of the CLM were significantly higher than that of the water extracts (CLC and CLH). During the adipocyte differentiation, the treatment of CLM more significantly inhibited lipid accumulation in 3T3-L1 cells than that of the water extracts. These results indicate that the stimulation of radical scavenging potential and the inhibition of adipogenesis were brought on by the lipophilic compounds of turmeric.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.1908-1918
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• 1991

Fatigue tests have been carried out to measure the degradation of the residual strength and the fatigue life in carbon/epoxy (0/45/90/-45)$_{2s}$ composite materials. Theoretical predictions of residual strength and fatigue life were compared with experimental results. Distribution characteristics were studied using the probability of failure based on the cumulative distribution function and median rand. The static ultimate strength of carbon/epoxy composites used herein is observed to be relatively higher than that of existing similar composites ; while fatigue life is shorter due to the brittleness of matrix. The fatigue life obtained in these experiments is shorter than that estimated by residual strength degradation model when the stress level above 0.6 For the stress level of 0.6, the experimental value was abruptly increased. The cumulative distribution function for the static ultimate strength is well correlated to that for the strength converted from the measured fatigue life. Also, the predicted distribution of residual strength shows good agreement with the experimental results. Therefore, it is proven that the residual strength degradation model is reasonable.e.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.316-321
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• 2003

Analysis of breeding gains in grain yield has been intensively conducted in wheat, barley, oat, maize, and soybean. Such information is limited in rice. The objective of this study was to compare the breeding gains and cultural gains contributed to yield gains of Korean rice varieties since early 1900s. Two sets of yield data were used for analysis; the historical yield data of 1908 for old japonica cultivars, and present yield data in the years from 1996 to 1998 for the six cultivars, consisting of previous two old cultivars and four contemporary cultivars. The old cultivars were two native cultivars, Jodongi and Damageum, while contemporary cultivars were two premium quality japonica cultivars, Hwaseongbyeo and Dongjinbyeo, and two Tongil-type cultivars, high yielding cultivars developed from indica/japonica hybridization, Milyang23 and Dasanbyeo. The yield differences of old cultivars between the experiments in 1908 and the experiments from 1996 to 1998 were estimated as cultural gains (1.84 tons $\textrm{ha}^{-1}$) due to the improvement of cultivation technology. Yield differences between the old cultivars and contemporary cultivars were considered total yield gains during the periods. These were 2.51 tons $\textrm{ha}^{-1}$ for japonica cultivars and 3.81 tons $\textrm{ha}^{-1}$ for Tongil-type cultivars. From these data, the genetic gain of 0.67 tons $\textrm{ha}^{-1}$ and 1.97 tons $\textrm{ha}^{-1}$ were estimated for japonica cultivars and Tongil-type cultivars respectively. The ratio between cultural gain and genetic gain appeared to be 2.7:1 for japonica cultivars and 1:1 for Tongil-type cultivars. This analysis clearly showed the higher genetic contribution in Tongil-type cultivars than in japonica cultivars, suggesting a guideline to be used when planning new yield improvement programs. Additional implication has emerged when a better yield response to modem cultivation technology was found in one of the old cultivars, suggesting the combined improvement between breeding and cultural improvement is necessary for attaining the maximum yield capacity of a crop.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.10
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• pp.1908-1914
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• 1992

A significant drag reduction in the turbulent flow of CWM(coal Water Mixture) adding minute amounts of high molecular weight polymer additives has been obtained and it was compared with pure CWM.However, the rate of drag reduction could come down with flow time, which is caused by polymer degradation, The rate of drag reduction and polymer degradation is affected by polymer type, concentration, molecular weight, and flow velocity. In the present investigation, these important parameters were evaluated for their influences on polymer degradation in order to find out stable conditions for CWM transportation with time. It was necessary to determine the more effective type of polymer additives to guarantee the optimum conditions for CWM transport. Experiments were undertaken with a test section of pipe diameter 9.8mm and pipe length 3500mm(L/D=357) in a closed loop, and polyacrylamide and polyetylene oxide were utilized as polymer additives. The tests were carried out under the conditions of 200, 400, 700ppm of polymer concentrations. CWM concentrations utilized were 5% and 10% with flow velocities of 4.9m/s and 6.1m/s. Experimental data show that polyehylene oxide degraded faster than polyacrylamide in CWM transport, and polyacryamide is considered to be a more effective candidate as additive for long time-CWM transport. Polymer degradation is also found to be more likely at lower polymer concentrations, at higher flow velocities, and higher CWM concentrations.

• Journal of fish pathology
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• v.14 no.1
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• pp.21-30
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• 2001

From March 1998 to April 2000, 4 species of marine fishes including black rockfish (Sebastes schlegeli), goby (Acanthogobius flavimannus), fine-spooted flounder (Pleuronichthys cornutus), and croaker (Nibea albiflora) were captured from the coastal area of the Gogunsan island located in the mouth of the Kum River, and greenling (Hexagrammos otakii) was sampled from the coastal areas of the Gogunsan island and the Wan-do. Trematodes from the stomach and the intestine of the fishes were detected and identified on the basis of the morphological characteristics. Four species of trematodes were detected in the stomach and the intestine of the examined fishes ; Opecoelus lobatus Ozaki, 1925 from black rockfish, fine-spotted flounder and greenling, Coitoecum glandulosum Yamaguti, 1934 from goby, Phyllodistomum sp. Braun, 1899 from croaker, and Pharyngora sp. Lebour, 1908 from greenling captured from Wan-do. This report gave morphological descriptions of O. lobatus, Pharyngora sp. and Phyllodistomum sp. from coastal marine fishes in Korea.

• Journal of Ecology and Environment
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• v.33 no.1
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• pp.47-57
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• 2010

To understand day-to-day fluctuations in soil moisture content in Seoul, I simulated daily soil moisture content from 1908 to 2009 using long-term climatic precipitation and temperature data collected at the Surface Synoptic Meteorological Station in Seoul for the last 98 years with a hydrological simulation model, BROOK. The output data set from the BROOK model allowed me to examine day-to-day fluctuations and the severity and duration of droughts in the Seoul area. Although the soil moisture content is highly dependent on the occurrence of precipitation, the pattern of changes in daily soil moisture content was clearly quite different from that of precipitation. Generally, there were several phases in the dynamics of daily soil moisture content. The period from mid-May to late June can be categorized as the initial period of decreasing soil moisture content. With the initiation of the monsoon season in late June, soil moisture content sharply increases until mid-July. From the termination of the rainy season in mid-July, daily soil moisture content decreases again. Highly stochastic events of typhoons from late June to October bring large amount of rain to the Korean peninsula, culminating in late August, and increase the soil moisture content again from late August to early September. From early September until early October, another sharp decrease in soil moisture content was observed. The period from early October to mid-May of the next year can be categorized as a recharging period when soil moisture content shows an increasing trend. It is interesting to note that no statistically significant increase in mean annual soil moisture content in Seoul, Korea was observed over the last 98 years. By simulating daily soil moisture content, I was also able to reconstruct drought phenomena to understand the severity and duration of droughts in Seoul area. During the period from 1908 to 2009, droughts in the years 1913, 1979, 1939, and 2006 were categorized as 'severe' and those in 1988 and 1982 were categorized as 'extreme'. This information provides ecologists with further potential to interpret natural phenomenon, including tree growth and the decline of tree species in Korea.