• Journal of the Korean Geographical Society
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• v.40 no.6 s.111
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• pp.716-729
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• 2005

In the Yeongpyeong River, one of the branches of Hantan River, there 4 fluvial terraces are identified. During the Quaternary, lava flow from Hantan River had gone 4.5km into upstream Part of the Yeongpyeong River and damed its entrance, and resultantly its lower basin had become a lava-damed paleolake. This study deals with fluvial terrace surface classification, stratigraphic analysis, deposits analysis, and OSL age dating in from Gungpyeongri to Seongdongri in lower reach of Yeongpyeong River, in order to identify Seomorphological Process of the terrace landforms relating to duration of lava-damed paleolake. Terrace surface T4, named Baekeuiri Formation, has been located under Jeongok lava layer to indicate pre-lava river bed. Terrace surfaces T3 and T2 are supposed to be formed during paleolake time, based on $3{\~}4m$ thick sand deposits including pebble and cobble layers, and clay and silt layers intersected with sand ones in nearly horizontal bedding. Terrace T1 is estimated to be formed as post-lake fluvial terrace after dissection of lava dam, based on the more fresh phase of deposits and very low height from present riverbed. The results of the OSL age dating for the T3 deposit layers indicate approximately $33{\~}40ka$, and still lake phase at that time.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.1019-1025
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• 2006

Two experiments were conducted separately to study the effect of astaxanthin on production performance and egg quality in laying hens and meat quality in finishing pigs. In Experiment 1, four hundred Brown Hy-Line layers, 26 weeks of age, were randomly divided into five treatments according to a single factorial arrangement. Each treatment had four replicates comprising 20 birds each. The dietary treatments were: 0, 0.7, 0.9, 1.1 and 1.3 ppm of astaxanthin fed for 14 days. Then all the birds were fed an astaxanthin-free diet (0 ppm astaxanthin) for an additional 7 days. The results showed that dietary astaxanthin had no significant effect on layer production performance. There was no significant effect (p>0.05) on egg weight, yolk height and Haugh unit (HU) with increasing dietary astaxanthin level and increased storage time. Yolk color was linearly increased (p<0.01) with the increasing dietary astaxanthin level and significantly decreased with the increasing storage time (p<0.05). The TBARS value in yolk decreased linearly (p<0.05) with increasing amount of dietary astaxanthin and storage time. When the diets were replaced with the astaxanthin-free feeds, all parameters concerning egg quality decreased with increasing days of measurement, especially the yolk color, and HU significantly decreased (p<0.05). In experiment 2, thirty-six barrows ($L{\times}Y{\times}D$), $107{\pm}3.1kg$ BW, were randomly divided into three treatments according to a single factorial arrangement. Each treatment had three replicates comprising 4 pigs each. The dietary treatments were: 0, 1.5 and 3.0 ppm of astaxanthin fed for 14 days. The results showed that dietary astaxanthin had no significant effects on production performance. There was a linear effect (p<0.05) on dressing percentage, backf.at thickness and loin muscle area with increasing dietary astaxanthin level. There were no significant effects (p>0.05) on the TBARS value, drip loss, meat color, marbling and $L^*$, $a^*$, $b^*$ values. Cholesterol concentration in meat was not affected by dietary addition of astaxanthin. It could be concluded that astaxanthin supplementation was beneficial to improve egg yolk color; egg quality during storage and it also could improve the meat quality of finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.559-568
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• 2012

White (Lohmann LSL) and Brown (ATAK-S) laying hens, were reared under organic and conventional cage rearing systems, and the effects of the rearing system on performance parameters, egg production, egg characteristics, and immune response were investigated. For this purpose, a total of 832 laying hens of two commercial hybrids, i.e., 416 white (Lohmann LSL) and 416 Brown (ATAK-S) layers, were used. The experiment lasted between 23 and 70 wk of age. In this study, the white layers yielded more eggs as compared to the brown layers in both organic and conventional production systems. Egg weight exhibited a similar pattern to that of laying performance. However, the total hen-housed egg number for the white birds in the organic system was fewer than that of white birds in the conventional cage facility; conversely, a contradictory tendency was observed for the brown birds. Livability of the white layers in the organic system was remarkably lower (14%) than that of the brown line, whereas the white line survived better (3.42%) than their brown counterparts in conventional cages. The feed conversion ratio of the white hens was markedly inferior in the organic system as compared to that of the white hens in the conventional system, whereas relatively lower deterioration was reported in brown layers when reared in an organic system. The organic production system increased egg albumen height and the Haugh unit in eggs of the brown layers. The yolk color score of organic eggs was lower than that of conventional eggs for both brown and white hens. The egg yolk ratio of eggs from white layers was found to be higher in organic eggs as compared to those obtained in the conventional system. All organic eggs had heavier shells than those produced in the conventional system. Eggs from brown layers had more protein content than eggs from white layers. Neither housing systems nor genotype influenced egg yolk cholesterol concentration. When compared to conventional eggs, n-3 fatty acid content was lower in organic eggs, and the n-6:n-3 ratio was higher in organic eggs. In conclusion, two hen genotypes showed different responses in terms of performance and egg quality to two different rearing systems. A commercial white strain produced more eggs with higher egg quality as compared to a native brown strain. The brown strain was found to have adapted well to organic production conditions when survival and total egg number was taken into consideration.

• Progress in Medical Physics
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• v.9 no.4
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• pp.259-266
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• 1998

To achieve the 2D dose distribution around the designed high dose rate Ir-192 source substitution for Co-60 brachytherapy source, we determined the exposure rate constant and tissue attenuation factors as a large depth as a 20 cm from source center. The exposure rate constant is used for apparent activity in designed source with self-absorption and encapsulation steel wall. The tissue dose delivered from the 4401 segments of 2.5 mm in a diameter and 2.5 mm height of disk-type source layer. In the experiments, the tissue attenuation factors include the tissue attenuation and multiple scattering in a medium surrounding the source. The fitted the polynomial regression with 4th order for the tissue attenuation factors are very closed to the experimental measurement data within ${\pm}$1% discrepancy. The Meisberger's constant showed the large uncertainty in large distance from source. The exposure rate constant 4.69 Rcm$^2$/mCi-hr was currently used for determination of apparent activity of source and air kerma strength was obtained 0.973 for tissue absorbed dose from the energy spectrum of Ir-192 source. In our experiments with designed high dose rate brachytherapy source, the apparent activity of Ir-192 source was delivered from the 54.6 % of actual physical source activity through the self-absorption and encapsulation wall attenuations. This paper provides the 2-dimensional dose tabulation from unit apparent activity in a water medium for dose planning includes the multiple scattering, source anisotropy effect and geometric factors.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.489-497
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• 2000

Since Chinese cabbages weigh 3 to 5kgf and are big in size at the time of harvest, handling operations such as harvesting, loading and unloading including transportation require the highest labor demand among all other cultivation processes. Recently, though several cabbage harvesters were developed in Japan and Europe, those harvesters were not suitable for Chinese cabbages cultivated in Korea because of the size and shape. The cabbage harvester is almost meaningless without any proper cabbage piling and pallet unloading mechanism. Most harvesters developed so far adopted a sort of slide and free falling way in collecting cabbages into the pallet. Three or four labors are usually required for cleaning incoming cabbages and loading those in the pallet. Because of the required time for piling cabbages without severe damage and the required space capacity to carry empty and loaded pallets, harvesting speed should be adjusted in accordance with time required for consecutive operations. Up to now, any automatic or semi-automatic collecting device has not been developed in the world to pile cabbages on the layer one by one into the pallet in the ordered way with little damage and to unload pallet from the harvester continuously during the harvest process. To compromise system expenses and function, Semi-automatic cabbage piling and pallet unloading mechanism was devised and it required one labor. The foldable mesh pallet with a size of 1050mm x 1050mm x 1000mm and holding capacity of around 70 cabbages was utilized. The prototype for piling and unloading mechanism was composed of three parts such as feeding device, automatic piling device with retractable bellows, and pallet unloading device. Prior to developing the prototype, the geometric properties and the amount of the damage of the cabbage caused during the piling operation were investigated. Considering the height of the pallet, a series of cabbage carrying plates were mounted to the bracket chain to lift and to carry cabbages to the loading device. Indoor laboratory experiments showed that the cabbage carrying chain conveyor worked successfully. Considering the conveying speed 0.46m/sec of the pull up belt from the cabbages on the ground, the speed of cabbage carrying chain conveyor worked property in the range of 0.26m/sec to 0.36m/sec. The system allowed the operator to modify the position of cabbage slightly. Overall system worked successfully resulting into almost same capacity without severe damage to the cabbage as human did.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.3
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• pp.109-124
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• 2018

In order to find the optimum culture condition for marine free-living nematoda in the laboratory, various agar media were developed and experiments were carried on nematodes. Nematodes have collected from the bottom of the sandy sediments' surface layer (about 5cm sediment) of Taean Mallipo beach's intertidal zone. Especially, with regard to agar medium, Killian medium was transformed slightly, density of agar had made a difference and this agar medium(height 2.0 mm on diameter 60 mm Petri dish) was divided. It was mixed with 5 different species of microorganism as nematodes' live food and added each culture medium. Five individuals of Enoplolaimus sp. on each culture medium were grown in a culture medium which was set on $20^{\circ}C$ and light blocked. Moreover, as a result of the optimum culture condition, 1.0% density of agar showed the highest survival rates (the average time of survival is 246.8 hours). On the other hand, the 0.4% density of agar adding Killian medium, bacto peptone and beef extract showed the lowest survival rates, which indicates the average time of survival is 27.6 hours. About Bathylaimus sp., on Killian medium's 1.0% density of agar(no feeding amount) showed the highest survival rates, which connects that the hatching rate 94.7% after 99.5 hours and it laid 7 eggs averagely on the spawning amount and the hatching rate experiment.

• Fire Science and Engineering
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• v.19 no.1 s.57
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• pp.80-86
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• 2005

In this study effects of the natural wind and the forced smoke ejection by operating the exhaust fan are studied numerically to examine the flow characteristics of the smoke and heat generated from a fire on the platform of an underground subway station. Three different situations, including 1) the case with no natural wind and no exhaust fan operation, 2) the case with natural wind but no exhaust fan operation and 3) the case with no natural wind but exhaust fan operation, are considered for the numerical analyses. The numerical results show that the natural wind causes a rapid spread of the fire along the tunnel resulting in rapid spread of the smoke and heat over the platform which affects the escape. The operation of the exhaust fan also results in the rapid spread of smoke and heat over the platform, but the time required for reaching the safe escaping height of the smoke layer with the exhaust fan operation is much longer than that without the exhaust fan operation. The numerical results also show that the required capacity of the exhaust fan becomes larger when the effect of the natural wind is included.

• Atmosphere
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• v.26 no.2
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• pp.347-356
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• 2016

Radiosonde is an observation equipment that measures pressure (geopotential height), temperature, relative humidity and wind by being launched up from the ground. Radiosonde data which serves as an important element of weather forecast and research often causes a bias in a model output due to accuracy and sensitivity between the different manufacturers. Although Korean Meteorological Administration (KMA) and several institutes have conducted routine and intensive radiosonde observations, very few studies have been done before on the characteristics of radiosonde performance. Analyzing radiosonde observation data without proper understanding of the unique nature of those sensors may lead to a significant bias in the analysis of results. To evaluate performance and reliability of radiosonde, we analyzed the differences between two sensors made by the different manufacturers, which have been used in the campaign of Experiment on Snow Storm At Yeongdong (ESSAY). We improved a couple of methods to launch the balloon being attached with the sensors. Further we examined cloud-layer impacts on temperature and humidity differences for the analysis of both sensors' performance among various weather conditions, and also compared daytime and nighttime profiles to understand temporal dependence of meteorological sensors. The overall results showed that there are small but consistent biases in both temperature and humidity between different manufactured sensors, which could eventually secure reliable precisions of both sensors, irrespective of accuracy. This study would contribute to an improved sounding of atmospheric vertical states through development and improvement of the meteorological sensors.

• Journal of the Korean GEO-environmental Society
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• v.15 no.3
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• pp.65-74
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• 2014

Borehole investigation which is mainly used to figure out geotechnical characterizations at construction work has the benefit that it provides a clear and convincing geotechnical information. But it has limitations to get the overall information of the construction site because it is performed at point location. In contrast, geophysical measurements like seismic survey has the advantage that the geological stratum information of a large area can be characterized in a continuous cross-section but the result from geophysics survey has wide range of values and is not suitable to determine the geotechnical design values directly. Therefore it is essential to combine borehole data and geophysics data complementally. Accordingly, in this study, a three-dimensional spatial interpolation of the cross-sectional distribution of seismic refraction was performed using digitizing and geostatistical method (krigring). In the process, digital map were used to increase the trustworthiness of method. Using this map, errors of ground height which are broken out in measurement from boring investigation and geophysical measurements can be revised. After that, average seismic velocity are derived by comparing borehole data with geophysical speed distribution data of each soil layer. During this process, outlier analysis is adapted. On the basis of the average seismic velocity, integrated analysis techniques to determine the three-dimensional geological stratum information is established. Finally, this analysis system is applied to dam construction field.

• Applied Microscopy
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• v.32 no.2
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• pp.163-170
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• 2002

Experimatal maxillary sinusitis was induced in New Zealand white rabbits by blocking the maxillary sinus ostium. The distribution of lectin receptors was explored in the mucosa with induced maxillary sinusitis using colloidal gold label complex with lectin WGA purified from wheat germ (Triticum vulgaris). The lectin WGA gold complex, shown to recognize GlcNac (N-acetylglucosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections and viewed under the electron microscope. An increased height of the cylindric cells, ciliary loss and hyperplasia of the secretory cells were observed. Examination of normal sinus mucosa labeled with gold-labeled lectins showed the distribution of sialoglycoconjugates to be mainly in the ciliary layer and the granules in the secretory cells. Inflamed mucosa had increased labeling intensity of gold-labeled WGA in the cilia and the secretory granules. These results indicate that lectin WGA receptors are located in the cilia and secretory granules. Specific changes in the lectin binding pattern were apparent in the inflamed mucosa in the experimentally induced acute sinusitis, in comparison with normal mucosa, conceivably as a part of host defense reactions.