• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.97-110
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• 2007

A laser scanning technique has been attracting much attention as a new technology to acquire location information. This technique might be applicable to a wide range of areas, most notably in geomatics, due to its high accuracy of location and automation of high-density data acquisition. A alignment information extraction system on highway has been developed in this study by utilizing the advantages of the laser scanning technique. The system can accurately interpret the alignment information of highway and can be applied to actual works. To develop the alignment information extraction system on highway, an algorithm that can automatically separate a horizontal alignment into a straight line, a transition curve, and a circular curve was developed. It can increase its efficiency compared to the conventional methods. In addition, an algorithm that can automatically extract design elements of horizontal and vertical alignments of highway was developed and applied to an object highway. This yielded higher practicality with more accurate values compared to those from previous studies on the extraction of design elements of highway alignment. Furthermore, the extracted design elements were used to perform a virtual driving simulation on the object highway. Through this, data were provided for a visual judgment for judging visually whether the topography and structures were harmonized in a three-dimensional manner or not. The study also presents data that can serve as a basis to determine highway surface freezing sections and to analyze three-dimensional sight distance models. Through the establishment of a systematic database for diverse data on highway and the development of web-based operating programs, an efficient highway maintenance can be ensured and also they can provide important information to be used when estimating a highway safety in the future.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.943-951
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• 2004

As storing ginger roots under optimum conditions takes high cost, ginger roots are commonly stored in underground tunnels where the maintenance of optimum temperature and humidity is difficult. One of the methods fur long term storage of ginger roots is freezing. The objective of this research was to evaluate effect of storage temperatures and packaging methods on the quality of minced ginger prepared with frozen stored ginger. The minced ginger prepared with frozen stored ginger at $-20^{\circ}C$ was packed in bags, glass bottles and tubes, and then stored at 5 and $-20^{\circ}C$ for quality evaluation at 4 and 15 week-intervals. The changes of surface color, total free sugars, free amino acids and volatile compounds were less in the combined treatment samples than in control during storage, regardless of the storage temperature. The tube packing was the best for maintaining quality of minced ginger during storage among tested packaging methods. Sensory results showed that the minced ginger with the combined treatment and packed in tubes could be stored at 5 and $-20^{\circ}C$ for 12 and 45 weeks, respectively, without a significant drop in palatability.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.390-394
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• 2013

The aim of this study was to determine the optimal storage condition of pre-packed Hanwoo beef without freezing. Hanwoo loin was purchased from a local distributor at 48 h after slaughter, then sliced in $1.5{\pm}0.5$ cm thickness, and packed in a polyethylene (PE) tray covered with linear low-density polyethylene (LLDPE) film. The studied factors to set the optimal storage condition were chamber temperature (5, 2.5 and $-1^{\circ}C$ for 14 d), cooling method (direct and indirect cooling system), and ultraviolet (UV) light irradiation for beef surface sterilization (0, 30, 60, and 120 min). The changes of pH, thiobarbituric acid reactive substances (TBARS) and number of aerobic bacteria were measured during storage. Beef samples stored in $-1^{\circ}C$ showed the minimal increasing rate in TBARS and microbial growth. After 15 d of storage, there was no significant difference in pH and TBARS values. However, the microbial population of beef stored in direct type cooling chamber ($4.25{\pm}0.66$ Log CFU/g) was significantly lower than that of beef stored in indirect type chamber ($6.47{\pm}0.08$ Log CFU/g) (p<0.05). After 4 d of storage, 60 or 120 min UV light irradiated beef samples showed significantly lower microbial population, and at 14 d of storage, 60 min UV irradiated beef sample showed significantly lower microbial population ($3.14{\pm}0.43$ Log CFU/g) than control ($4.46{\pm}0.13$ Log CFU/g) (p<0.05). However, TBARS values of 60 or 120 min UV light irradiated beef samples were significantly higher than non-irradiated beef sample after 4 d of storage (p<0.05).

• Applied Microscopy
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• v.39 no.1
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• pp.65-72
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• 2009

Cryo-SEM which enables specimens to be observed in frozen form has been used to study liquid specimens in their native states. Cryo-methods, sample preparation for cryo-SEM, are quite complex and involve several discrete but vitally interconnected steps which are rapid cooling, fracturing, sectioning, etching and coating. It is important to select practical techniques and to optimize conditions of each steps considering analytic purpose and specimen characters, viz., sample dimension, water contents. In this study, etching methods and sample preparation before freezing had been studied for observation of cyanobacteria, Synechocystis sp. PCC 6803 using cryo-SEM and their cryo-SEM images were compared to Conventional SEM (CSEM) images treated by chemical fixation. We could observe the improved morphological images of the pili of the surface and membranes of Synechocystis sp. PCC 6803 and the three-dimensional architectures of their biofilm, which were difficult to observe using chemical fixation and CSEM. These results suggest that cryo-methods/cryo-SEM are useful techniques for morphological study of biological specimen.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.211-218
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• 2018

Different packaging methods and storage temperatures were tested to determine the storage stability of beef dry-aged for 21 days based on microbial, physicochemical, and sensory qualities. After completion of the dry aging, the dried surface of beef sirloin was trimmed off, and the beef was packaged using two different methods (oxygen-permeable wrap or vacuum packaging) and stored at different temperatures ($3{\pm}2^{\circ}C$ or $-23{\pm}2^{\circ}C$) for 0, 7, 14, or 21 days. Lipid oxidation and the sensory quality of the dry-aged beef were not affected by the packaging method and storage temperature during storage. No microbial growth was observed over the storage period in the vacuum-packaged dry-aged beef, regardless of the storage temperature. However, dry-aged beef in the oxygen-permeable wrap packaging showed microbial spoilage with 8.82 log CFU / g at day 7 of the refrigerated storage. The vacuum-packaged dry-aged beef showed the lowest values (p < 0.05) in $a^*$ and chroma at days 14 and 21 at $3^{\circ}C$, and days 7 and 14 at $-23^{\circ}C$, respectively. Therefore, it is recommended that dry-aged beef with wrap packaging stored in refrigerated conditions should be consumed as quickly as possible due to microbial growth. For long-term storage, dry-aged beef should be frozen because freezing can extend the color stability up to day 21 of storage without adverse effects on the hygienic or meat quality aspects of dry-aged beef.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.45-45
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• 2018

We had already reported the successful germination for green pods of purple lady's slipper orchid (Cypripedium macranthos Sw.). The green pod methods is to take immature seeds in green capsules, sterilize the capsule, and take out the sterile seeds. This method, however, needs very critical time of harvest. The critical time of seed harvest changes depending upon the species, condition of the specimen, and climatic influence, and the right time lies between 5 and 12 weeks after fertilization. In this study, the mature seeds were collected after 120-130 days with hand-polination of lady's slipper orchids. Mature seeds are usually dormant and it has to be overcome, either with hormone or storing the seeds near freezing for two or three months to break dormancy. The seeds were first surface sterilized with 70% ethanol and then transferred 1% NaOCl for 10-15 minutes, followed by rinses 3 times with sterilized distilled water. The cypripedium seeds consists of an embryo within a seed coat known as a testa. The testa is water repellent and the seed has a large air space between the embryo and testa so the seed tends to float on water. We had resolved the problems with vacuum pump to soak water into the testa before sterilization. The seeds were placed on liquid or agar solidified germination media. Cultures were incubated at $24{\pm}1^{\circ}C$ in dark. The seeds were germinated in 6-8 weeks in liquid suspension culture (germination percentage over 18%); however, the seeds on agar solidified media took more than 5 months to germinate and the germination percentage less than 5%. The most effective media for liquid culture was 1/4 strength Murashige and Skoog (MS) medium with 50 ml/l coconut water ($4brix^{\circ}$) at pH 5.8.

• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.32-42
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• 1966

The electrolysis of tungstic oxide dissolved in the bath of calcium chloride and calcium oxide was studied to produce metallic tungsten using carbon as anode and iron as cathode in the temperature range of 900^{\circ}$ to $1200^{\circ}C$. The binary phase diagrams $CaCl_2$-CaO and $CaCl_2-CaWO_4$ systems were constructed to determine the suitability of bath composition and the range of temperatures for the electrolysis. As $WO_3$ reacted with $CaCl_2$ to form oxychloride in the fused salt, the addition of the proper amount of CaO was necessary to avoid the loss of $WO_3$. The optimum compositions of fused bath were $CaCl_2$ 100 parts, CaO and $WO_3$ each 10 to 20 parts, with the CaO, $WO_3$ ratio greater than unity, to keep freezing point low and to prevent the vaporization of $CaCl_2$. The observed decomposition voltage at which $WO_3$ decomposes to W and CO was-0.1 volt, whereas the calculated was -0.3 volt. Metallic tungsten deposited at the cathode reacted easily with CO formed secondarily at the anode surface, to form WC below $1050^{\circ}C$, so that the cell temperature should be above $1050^{\circ}C$. The effects of cathode current densities on current efficiency were minor in the range of 1 to 5 $amp/cm^2$.

• Journal of the Korean GEO-environmental Society
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• v.17 no.1
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• pp.49-54
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• 2016

An active layer distributed on surface of an extreme cold region causes a frost heave by repeating the freezing and thawing according to the seasonal temperature change. Since the height of frost heave is greatly affected by the thickness of active layer, an accurate evaluation of the thickness of active layer is necessary for the safe design and construction of the infrastructure in the extreme cold region. In this study, dynamic cone penetrometer, which is miniaturized in-situ penetration device, is applied for the evaluation of active layer depth distribution. As the application tests, two dynamic cone penetration tests were conducted on the study sites located in Solomon and Alaska. In addition, ground temperature variations were obtained. As the results of the application tests, the depth of interface between the active layer and the permafrost was evaluated from the difference in dynamic cone penetration indexes of the active layer and the permafrost, and a layer was detected around the interface considered as an ice lens layer. Also, the interface depths between the above zero and the below zero temperature determined from the ground temperature variations correspond with the interface depths evaluated from the dynamic cone penetration tests. This study demonstrates that the dynamic cone penetrometer may be a useful tool for the evaluation of the active layer in the extreme cold region.

• Economic and Environmental Geology
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• v.42 no.1
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• pp.73-84
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• 2009

The stone Buddha and Shrine of Unjusa temple (Korean Treasure No. 797) at Hwasun formed in Koryo Dynasty is unique style which faces each other the back parts of south and north within the stone Shrine. The stone Buddha and Shrine is highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. To inquire into relative deterioration and environmental factor, air temperature and relative humidity of the stone Buddha and Shrine were monitored for a year of the indoor and outdoor, respectively. As a result, the temperature shows increase and decrease according to the seasons in the tendency to clear. While the relative humidity is high to keep all four seasons. Highly relative humidity environment induces dew condensation on the interior of stone Buddha and Shrine. The dew condensation is recorded at the spring, summer and winter season. The summer season is double the total of spring and winter season. In the case of summer, dew condensation is long time continued due to high temperature and relative humidity that is kept by more than nearly 100%. There is progress towards chemical weathering throughout dissolve rock properties and alteration on the rock surface. In the case of winter, dew condensation is not kept for a long time as summer. In the winter, which showing a below zero may add physical weathering throughout moisture that happen by dew condensation to repeat freezing and thawing. Therefore, the reduction plan of the relative humidity effect on dew condensation should be prepared.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.128-135
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• 2016

In the current concrete structure of the highway is still the major problem most of concrete deterioration caused by the freeze-thaw and deicing salt, which is of issues that are not completely resolved. In particular, a single freezing event does not cause much harm, durability of concrete under multi-deterioration environment by repeated freeze-thaw and deicing salt is rapidly degraded and reduce its service life. In this study, the exposure environmental condition according the regional highway points were established. The damage condition and chloride content of the concrete at general and severe environmental exposure condition were also investigated. In addition, the experimental test of chloride ion permeability, scaling resistant and freeze-thaw resistance were carried out to improve the durability of the mechanical placing concrete of subsidiary structure. According to the results of this study, in observation of concrete surface condition, the concrete exposed by severe environmental condition showed broad ranges of damage with high chloride contents. Meanwhile, the water-binder(W/B) ratio and the less water content, and fly ash concrete than the specified existing mix proportion is significantly improved the durability. Also, the optimal mix proportion derived for test is satisfied the strength and air contents, water-binder ratio, and durability criteria of concrete specifications, as well as service life seems greatly improved.