• Smart Media Journal
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• v.11 no.2
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• pp.31-38
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• 2022

Promptly predicting changes in the salinity in rivers is an important task to predict the damage to agriculture and ecosystems caused by salinity infiltration and to establish disaster prevention measures. Because machine learning(ML) methods show much less computation cost than physics-based hydraulic models, they can predict the river salinity in a relatively short time. Due to shorter training time, ML methods have been studied as a complementary technique to physics-based hydraulic model. Many studies on salinity prediction based on machine learning have been studied actively around the world, but there are few studies in South Korea. With a massive number of datasets available publicly, we evaluated the performance of various kinds of machine learning techniques that predict the salinity of the Nakdong River Estuary Basin. As a result, LightGBM algorithm shows average 0.37 in RMSE as prediction performance and 2-20 times faster learning speed than other algorithms. This indicates that machine learning techniques can be applied to predict the salinity of rivers in Korea.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.150-154
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• 1990

Various sterilization temperatures $(110^{\circ}C,\;120^{\circ}C,\;130^{\circ}C)$ and air volumes (air, 31ml, half-vacuum; 13ml, vacuum; -0.7ml) within the retort pouch were tested for the development of the simple retort rice processing techniques in which the pouch were filled with rice and water, and then sterilized. Water content of retort rice was found to be 59.0-63.3% resulting from mixing the rice and water in the ratio of 1:1.1. The most uniform water content was obtained from retort rice sterilized at $130^{\circ}C$ and packaged under vacuum. The larger water content differences were observed with the increase in internal air volumes within the retort pouch. Spreading degree of retort rice was geater than that of general cooked rice, was lower in upper layer than in low layer, and became lower with the larger air volume and higher sterilization temperature. a degree of rice became higher with the Increase of sterilization temperature but that was not affected by the internal air volume of the pouch. The higher sterilization temperature and the lower the air volume, the higher the whiteness was. The highest whiteness was obtained by packaging under vacuum and sterilizing at $130^{\circ}C$. Intact degree was much higer in packaging under air than vacuum. In sensory evaluation the retort rice of vacuum pack was good in color and spreading degree but not in appearance because of blocking and deforming, but that of air pack was good in texture on the contrary. The best quality was obtained by packaging under half-vacuum and sterilizing at $130^{\circ}C$.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.337-340
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• 2005

Context-awareness techniques in ubiquitous computing environment provide various services to users who need to get information via the analysis of collected information from sensors in a spatial area. Context-awareness has been increased in ubiquitous computing and is applied to many different applications such as disaster management system, intelligent robot system, transportation management system, shopping management system, and digital home service. Many researches have recently focused on services that provide the appropriate information, which are collected from Internet by different kinds of sensors, to users according to context of their surrounding environment. In this paper, we propose an abstraction model to manage the large-scale contextual information and their metadata which are collected from different kinds of in-situ sensors in a spatial area and are presented them on the web. This model is composed of the modules expressing functional elements of sensors using sensorML(Sensor Model Language) based on XML language and the modules managing contextual information, which is transmitted from the sensors.

• The Microorganisms and Industry
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• v.19 no.2
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• pp.34-41
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• 1993

Industrial strain improvement is concerned with developing or modifying microorganisms used in production of commercially important fermentation products. The aim is to reduce the production cost by improving productivity of a strain and manipulating specific characteristics such as the ability to utilize cheaper raw materials or resist bacteriophages. The traditional empirical approach to strain improvement is mutation combined with selection and breeding techniques. It is still used by us to improve the productivity of organisms in amino acids, organic acids and enzymes production. The breeding of high L-lysine-producing strain Au112 is one of the outstanding examples of this approach. It is a homoserine auxotroph with AEC, TA double metabolic analogue resistant markers. The yield reaches 100 g/l. Besides, the citric acid-producing organism Aspergillus niger, Co827, its productivity reaches the advanced level in the world, is also the result of a series mutations especially with $^60Co{\gamma}$-radiation. The thermostable .alpha.-amylase producing strain A 4041 is the third example. By combining physical and chemical mutations, the strain A 4041 becomes an asporogenous, catabolite derepressed mutant with rifamycin resistant and methionine, arginine auxotroph markers. The .alpha.-amylase activity reaches 200 units/ml. The fourth successful example of mutation in strain improvement is the glucoamylase-producing strain Aspergillus niger SP56, its enzyme activity is 20,000 units/ml, 4 times of that of the parental strain UV-11. Recently, recombinant DNA approach provides a worthwhile alternative strategy to industrial strain improvement. This technique had been used by us to increase the thermostable .alpha.-amylase production and on some genetic researches.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.363-367
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• 1996

Background: Recently postoperative pain control with continuous epidural analgesia has been increased. This study aimes to evaluate backpain following continuous epidural analgesia by pressure threshold meter (algometer). Methods: After informed consent, 50 ASA physical status I or II patients undergoing elective gynecologic surgery were selected. After placing epidural catheter, patients received morphine 0.05mg/kg with 0.25% bupivacaine 5 ml followed by continuous infusion of 0.125% bupivacaine 100 ml with morphine 4 mg for 48 hours. backpain was measured by pressure algometer over lumbar paraspinalis at the L4 level, 5 and 7 cm from the midline on preoperative, operation day, 1st, 2nd, 3rd, and 4th postoperative days. Results: Postoperative mean pressure thresholds of were higher than preoperative value (p<0.05). Conclusion: The continuous epidural analgesia dose not provide or aggravate postoperative backpain, but it must be evaluated for long term follow-up.

• Biomedical Science Letters
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• v.8 no.3
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• pp.161-165
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• 2002

Apoptosis can be difficult to detect in routine histological sections. Since extensive DNA fragmentation is an important characteristic of this process, visualization of DNA breaks could greatly facilitate the identification of apoptotic cells. Several techniques for the qualitative and quantitative detection of this process have been established; recently, an in situ nick end-labelling technique based on the detection of DNA fragmentation, which is a molecular characteristic of apoptotic cell death, was described. Applying this method to paraffin sections of rat tissues, sensitivity was observed to be inconsistently low with regard to the expected number of apoptotic cells. I describe a new modified method for formalin-fixed, paraffin-embedded tissue sections, pretense pretreatment to permeate the tissue sections that involves an TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) is acknowledged as a method of choice in the rapid identification and quantification of the apoptotic cell fraction in paraffin tissue preparations. TUNEL was performed without apoptosis and with apopotosis samples to each of the three concentrations of proteinase K (10, 25, 40 mg/ml) pretreatments. In this study, I show that chemical pretreatments of the tissue sections in proteinase K (25 mg/ml for 15 min at room temperature) considerably enhances the sensitivity of this nick end labelling technique.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1116-1123
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• 2020

Velvet antler (VA) is a historically traditional medicinal supplement and is well known in Asian countries for its pharmaceutical and health benefits. The objectives for this study were to optimize the hot water extraction (HWE) of VA for the Korean VA industry, and to determine the most effective pretreatment method among microwave (MW), ultrasonication (US), and enzymatic (EZ) techniques. Using response surface methodology, optimum extraction temperatures and times were determined by central composite design configuration based on extraction yield and sialic acid content. Various quality parameters of VA extract including yield, soluble solid, protein, and sialic acid contents were also compared with the conjunction of HWE and pretreatment. The yield and sialic acid content of VA extract were determined to be 40% and 0.73 mg/g, respectively, under an optimum temperature of 100℃ at 24 h of extraction time. The yields from VA extracts pretreated with MW, US, and EZ were 17.42%, 19.73%, and 29.15%, respectively. Among the tested commercial enzymes, pepsin was the most effective proteolytic enzyme and led to the highest yield (47.65%), soluble solids (4.03 °brix), protein (1.12 mg/ml), and sialic acid (3.04 mg/ml) contents from VA extract.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.4A
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• pp.394-402
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• 2008

In this paper, we propose a novel soft output generation method for spatially multiplexed MIMO systems. The receiver complexity of spatially mutiplexed MIMO system is in proportion to the number of candidate vectors. The ML signal detection method considers all possible vectors as candidates, thereby achieving a high performance, however, its complexity is very high. Low complexity receiver techniques involving a small number of candidate vectors, provide soft output values of low reliability. In this paper, we propose a method to improve reliability of the soft output values obtained using a small number of candidate vectors.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.266-272
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• 1998

The present study investigated the antitumor activity of the aqueous-alcoholic extracts from unripe cotton balls of Gossypium indicum. An Exposure of murine B16 melanoma and L1210 lymphoma cells to the extracts resulted in their severe deaths in time- and concentration-dependent manners. Of the extracts, hydrophilic fractions were most efficacious for the antitumor activity and found to contain certain amounts of catechin and its derivatives. The hydrophilic extract fraction C36B2-8 had approximately 10 times more cytotoxic effects on B12 and L1210 cells than on isolated murine thymocytes. High concentrations (>150 $\mu$g/ml) of C 36B3-8 mainly induced necrotic cell death. At low concentrations (<100 $\mu$g/ml), however, C 36B3-8 induced not only necrosis but also apoptosis of the two tumor cell lines, which was proved by the TUNEL staining and DNA fragmentation techniques. The data indicate that certain ingredients of the cotton ball extract of G. indicum have an antitumor activity.

• The Journal of the Korean dental association
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• v.15 no.8
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• pp.611-615
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• 1977

The author observed histochemically the nature of the calcified tissue in the rabbit dental pulp, induced by pulpal injection of potassium permanganate. The pulp of rabbit mandibular incisors were exposed and enlarged by a dental hand reamer. The exposed pulps were injected with 0.05ml of 20mM solution of potassium permanganate dissolved in Ringer's solution in experimental tooth. Also the control tooth received a pulpal injection of 0.05ml of Ringer's solution. After pulpal injection, the tooth was plugged with a gutta-percha root canal point. The staining techniques were hematoxylin-eosin stain, van Gieson stain, PAS reaction, toluidine blue stain, alcian blue-hematoxylin stain and colloidal iron-picric acid stain. The results were as follows: 1. The pulp on experimental tooth showed osteodentin-like calcified tissue. Also, in some areas, false denticle-like substance were observed. 2. The central portion of the calcified matrix showed metachromasia in toluidine blue stain had strong staining capacity in alcian blue stain. 3. The peripheral portion of the calcified tissue revealed marked van Gieson positive reaction for collagen. But their staining ability in alcian blue was slight and metachromasia was not appeared.