• Korean Journal of Ichthyology
• /
• v.28 no.1
• /
• pp.9-18
• /
• 2016

Histological and morphological development of the digestive tract of sevenband grouper were observed from after hatching to 60 days. Fishes were fed with rotifer (Brachionus rotundiformis) and chlorella (Chlorella ellipsoidea) after hatching from 2 to 20 days rotifer and brine shrimp (Artemia salina) in after 20 days rotifer, brine shrimp and semi-dry artificial diet in after 23 days. Histological and morphological development of ten larvae was observed by paraffin embedding method after fixing in 10% neutral buffered formalin. Sevenband grouper RLG showed characteristics of carnivorous fish by average 0.87. Larvae after hatching can't open the mouth and anus digestive tract was observed in a straight line following yolk sac. Larvae was observed feeding activity by opening the mouth and anus. Metamorphosis started 8 days after hatching. Esophagus divided four layer, and goblet cell was observed in esophagus, mid intestine and rectum. Larvae started cannibalism and it was caused by difference of growth. The inside of stomach was differentiated to cardiac orifice, body of stomach, pyloric stomach, and pyloric caeca. Goblet cell was observed all intestine. Gastric gland differentiated after hatching 28 days in stomach. Secretion of gastric juice was found at stomach and mucosal fold pyloric caeca. Even thought the inside of stomach expended and the number of gastric gland increased consistently and goblet cell in intestine and mucosa became longer, histochemical changes follow couldn't be found during transforming juveniles 38 days after hatching.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.2 no.3
• /
• pp.87-99
• /
• 1982

This study proposes a reliability based design criteria for the R.C. superstructures of highway bridges. Uncertainties associated with the resistance of T or rectangular sections are investigated, and a set of appropriate uncertainties associated with the bridge dead and traffic live loads are proposed by reflecting our level of practice. Major 2nd moment reliability analysis and design theories including both Cornell's MFOSM(Mean First Order 2nd Moment) Methods and Lind-Hasofer's AFOSM(Advanced First Order 2nd Moment) Methods are summarized and compared, and it has been found that Ellingwood's algorithm and an approximate log-normal type reliability formula are well suited for the proposed reliability study. A target reliability index (${\beta}_0=3.5$) is selected as an optimal value considering our practice based on the calibration with the current R.C. bridge design safety provisions. A set of load and resistance factors is derived by the proposed uncertainties and the methods corresponding to the target reliability. Furthermore, a set of nominal safety factors and allowable stresses are proposed for the current W.S.D. design provisions. It may be asserted that the proposed L.R.F.D. reliability based design criteria for the R.C. highway bridges may have to be incorporated into the current R.C. bridge design codes as a design provision corresponding to the U.S.D. provisions of the current R.C. design code.

• Journal of Korea Water Resources Association
• /
• v.49 no.2
• /
• pp.83-94
• /
• 2016

Geomorphological, bed material and hydraulic characteristics are basis informations for the planning, design and management of the river in the aspect of flood control and environmental conservation, and it is very important to use these informations for the design of stable channel. In this study, dominant discharge was selected, geomorphological and hydraulic characteristics were analyzed using that discharge and also the characteristics of bed materials distribution were analyzed and bed materials-flow resistance relationship was evaluated, for the upstream section of Namgang dam. The dominant discharge was estimated a return period of approximately 1.5 year and stream type were classified Segment 1 and Segment 2 in this stream. Also, the frequency of riffle-pool showed 4.4 because this study area has the characteristics of natural channel that have not channel-crossing structures. In dominant discharge, according to the results that analyzed relationship between $h/d_{50}$ and $V/u_*$ to calculate flow resistance by bed materials, Julian's formula showed to appropriate in channel where is relatively close to natural river and is predominantly consisted of gravel, cobble, boulder and rock in mountain, and it was confirmed that the image processing methodology will be easily applied to the analysis of bed materials distribution in future.

• Management & Information Systems Review
• /
• v.36 no.2
• /
• pp.81-92
• /
• 2017

This study was to investigate the elasticity in tourism demand of Chinese tourists visiting Malaysia through ARDL models by using Chinese tourists arrivals, GDP, CPI, transportation costs and others. When China was implementing an open-door policy with foreign countries in the early 15th century, the movement of Chinese was very limited, and then communication between China and other countries was very weak. However, the Chinese government persistently and entirely implemented an open-door policy by participating in the World Trade Organization(WTO) in 2001. The Chinese government has opened the economy through foreign direct investment by providing various incentives for foreign investment. As a result, inbound and outbound Chinese movements increased in the early 21st century. China was one of the top five most visited tourist destinations in the world by 2016, and also Chinese tourists traveling abroad increased, so they made Malaysia a popular tourists destination because of increase sharply to around 1.41 million. This study examined the significance of major economic factors affecting the increase in Chinese tourists arriving in Malaysia. Other factors that induced their arrival included income, tourism prices, transportation costs and promotional activities. Short-run shocks from the Asian economic crisis and the outbreak of SARS were included to understand how tourism demand in Malaysia was affected. Finally this study found that the combination of the ARDL and the Error Correction Model were useful to statistically estimate the elasticities of tourism demand.

• Journal of Korea Water Resources Association
• /
• v.39 no.5 s.166
• /
• pp.405-415
• /
• 2006

The deposition of sewer solids during dry weather in combined sewer systems results in a loss of flow capacity that may restrict flow and cause a local flooding and enhanced solids deposition. Sewer solid accumulations in drainage systems also create the 'first-flush' phenomena during wet weather runoff periods. In order to solve these problems, measurement of these loadings for a given sewer system for extended period is needed but this task is very difficult and extremely expensive. In this study, generalized procedures for estimating sewer sediment solid during dry weather in combined sewer systems developed by the U. S. Environmental Protection Agency were applied in a drainage system in Korea. As result, the appropriate equation can be selected and applied according to the available data. However, the estimated solid sediment shows considerable difference between methods which classified by model and estimation methods of variable. The estimated values using equations (1) $\sim$ (4) are greater than that of equations (5) $\sim$ (9) and intermediate models show greater values than elaborate or simplest models. The comparison between simulated and measured solid deposition is difficult due to the absent of measurement data, but this estimation method can be used usefully for the management of sewer solid with reduction of cost and effort if the measurement is carried out and the equation is adjusted according to the actual drainage systems in Korea.

• Journal of The Korean Dental Society of Anesthesiology
• /
• v.11 no.2
• /
• pp.141-145
• /
• 2011

배경: 협조가 불가능하거나 진정법 하 치과치료가 여의치 않을 경우 전신마취 하 치료를 계획하게 된다. 하지만 전신마취 하 치료시 기관내 삽관이 여의치 않은 경우를 종종 경험하게 된다. 이와같은 경우 기관지경을 이용한 기관내 삽관을 시행한다. 기관지 내시경을 환자의 성문에 근접하게 전진시킬 경우 기관지 내시경 하 시야확보가 용이한 점을 감안 시 비공 - 성대간 거리를 예측하는 것은 매우 유용할 것으로 생각된다. 또한 비공 - 성대간 거리를 추정하게 되면 맹목적 비강내 기관내 삽관을 하는데도 도움이 된다. 방법: 본 연구는 전신마취하 치과치료가 예정되어 있는 62명의 소아환자들을 대상으로 하여 신체변수와 비공 - 성대거리와의 관계를 확인해보고자 하였다. 선형회귀분석을 시행하여 다음과 같은 결론을 도출하였다. 결과: 소아환자들에 있어 비공 - 성대간 거리는 환아의 신장, 체중, 연령 등과 상관관계를 나타내었다. 비공 - 성대간 거리와 상관관계를 보인 변수들 중 에서 신장과의 상관계수가 가장 높았다. 선형회귀분석을 통해 비공 - 성대간 거리를 예측하는 다음과 같은 회귀식을 구하였다. 비공 - 성대간 거리 = (4.8 + 신장(cm)) ${\times}$ 0.07 고찰: 본 연구에서 구해진 회귀식을 이용하여 기도유지가 어려운 소아의 기도유지 하는데 큰 도움이 될 것으로 생각된다.

• Applied Biological Chemistry
• /
• v.7
• /
• pp.29-33
• /
• 1966

This experiment was conducted to study the relationship between the energy value and the nitrogen content in the rat urine. Thirteen rats for ad libitum feeding group and 16 rats for two-meal group were employed in this experiment. The experimental period consisted of 22 days with a preliminary period of 10 days. During the last eight days of the experiment the urine was collected quantitatively. The rats fed two-meal per day excreted significantly (p<0.005) more nitrogen and energy in the urine than those fed ad libitum. A linear relationship between the energy concentration and nitrogen content was found. The urinary energy value was increased as the urinary nitrogen content was increased. A prediction equation was derived to compute the energy value from the content of nitrogen as follows: Y=8.924X+0.182 $S_{y{\cdot}x}=0.788$ where Y=urinary energy(kcal/100 ml) X=urinary nitrogen(gm/100 ml) Since the standard deviation of estimate is in small magnitude (0.788 kcal) when it is compared with the amount of intake of gross energy, digestible energy or metabolizable energy, this equation can be used safely to estimate the energy value from nitrogen content. Consequently, considerable amound of time and labor for the actual determination of energy can be saved. The ratio of energy to nitrogen was found to be 9.4 for ad adlibitum group and 8.6 for two-meal group. No significant difference between two group in this respect was observed.

• The KIPS Transactions:PartA
• /
• v.12A no.4 s.94
• /
• pp.305-312
• /
• 2005

In this paper, we present algorithm-level techniques for energy-efficient design at the algorithm level using FPGAs. We then use these techniques to create energy-efficient designs for two signal processing kernel applications: fast Fourier transform(FFT) and matrix multiplication. We evaluate the performance, in terms of both latency and energy efficiency, of FPGAs in performing these tasks. Using a Xilinx Virtex-II as the target FPGA, we compare the performance of our designs to those from the Xilinx library as well as to conventional algorithms run on the PowerPC core embedded in the Virtex-II Pro and the Texas Instruments TMS320C6415. Our evaluations are done both through estimation based on energy and latency equations on high-level and through low-level simulation. For FFT, our designs dissipated an average of $50\%$ less energy than the design from the Xilinx library and $56\%$ less than the DSP. Our designs showed an EAT factor of 10 times improvement over the embedded processor. These results provide a concrete evidence to substantiate the idea that FPGAs can outperform DSPs and embedded processors in signal processing. Further, they show that PFGAs can achieve this performance while still dissipating less energy than the other two types of devices.

• Radiation Oncology Journal
• /
• v.16 no.4
• /
• pp.505-515
• /
• 1998

Purpose : This study is intended to understand the sensitometric characteristics and the emulsion properties of the commercially available CEA TVS film in comparison with the Kodak X-Omat V film. Materials and Methods : For this purpose, we have formulated an analytic expression of the characteristic curves for x-ray film exposed to mixed radiation of electrons, photons, and visible light. This mathematical expression was developed based on reaction-rate and target-hit theories. Unlike previous expressions. it relates optical density to emulsion properties such as grain size and silver bromide content We have also developed a quantity which characterizes the film response to visible light relative to that to photons and electrons. This quantity could be expressed as a function of grain area. Thus, we have developed mathematical expressions and quantities with which the emulsion properties of the films can be revealed based on the sensitometric characteristics. Demonstrating the use of this analytical study, we exposed CEA and Kodak verification films to the mixed radiation of electrons, photons, and visible light, and interpreted the experimental results accordingly. Results : We have demonstrated that: (1) the saturation density increases as the silver bromide content increases, (2) the time required to reach the threshold dose (to which the film begins to respond) when films are exposed to visible light decreases as the grain size increases, and (3) the CEA film contains more silver bromide. whereas the Kodak film contains larger grains. These findings were supported by the data provided by the manufacturers afterward. Conclusion : This study presented an analytical and experimental basis for understanding the response of X-ray film with respect to the emulsion properties.

• The Korean Journal of Nuclear Medicine
• /
• v.28 no.3
• /
• pp.364-370
• /
• 1994

The purpose of this study is to evaluate the clinical application of the no carrier added $[^{51}Cr]Cr(III)$-EDTA complexes, produced at Korea Cancer Center Hospital. The $[^{51}Cr]Cr(III)$-EDTA complexes, usefut for measurement of GFR were prepared at room temperature in the presence of bicarbonate catalysts. The radiochemical purity of $[^{51}Cr]Cr(III)$-EDTA was over 99% by paper electrophoresis. The time activity curves were obtained by counting the blood samples from 5 volunteers and counting the head and neck regions with whole body counter after injection of the $^{51}Cr$-EDTA, respectively. After the nonlinear regression, the area under curve was obtained. The plasma clearance of the $^{51}Cr$-EDTA was calculated with injected dose/AUC. The clearance rate calculated with the head and neck counting data was in good agreement with the result from the plasma sample radioactivity at 1-3 hrs after injection. From this result, the counting of head and neck region and the nonlinear regression by 2-compartment model could be applied for the measurement of the clearance rate. Using MIRD system, the absorbed radiation dose was calculated by residence $time{\times}S$. The absorbed whole body radiation dose was negligibly small.