• Economic and Environmental Geology
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• v.36 no.6
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• pp.441-455
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• 2003

The most common water types are found to be Ca-$HCO_3$, Ca-Na-$HCO_3$ and Ca-Na-$HCO_3$-Cl in Gwangju groundwater. Groundwater near the Gwangju stream are characterized Ca-Cl water type, with over 50 mg/L of C1- and 400 ${\mu}$S/cm of EC. The systematic variation of $Cl^-$, $HCO_3^-$,- EC and ${\gamma}^{18}O$ values in groundwater with distance away from drainages is caused by streamwater infiltration. Stable isotope data indicate that ${\gamma}$D and ${\gamma}^{18}O$ values of groundwaters near drainages were enriched by evaporation effect, showing a equation of ${\gamma}$D=7. 1${\times}{\gamma}^{18}O$-1. ${\gamma}^{18}O$ values over -6${\textperthansand}$ are anomalous in the unconfined groundwater zones, which are influenced by the local surface water enriched in $^{18}O$ composition. Groundwater in highland shows remarkably light ${\gamma}^{18}O$ values below -8$\textperthousand$. The infiltration of streamwater is dominant in unconfined alluvium aquifer near drainages. ${\gamma}^{13}$CDIC values (-17.6∼-15.2$\textperthousand$) of groundwaters near drainages revealed that dissolved inorganic carbon (DIC) is predominantly originated from natural soil-derived $CO_2$. ${\gamma}^{15}N$ and ${\gamma}^{18}O$ values of nitrate are 0∼17.0${\textperthansand}$ and 6.6∼17.4${\textperthansand}$, respectively. Relationship between ${\gamma}^{15}N$ and ${\gamma}^{18}O$ shows a systematic isotopic fractionation caused by denitrification of 40∼60%, suggesting that the major source of groundwater nitrate originated from nitrate of soils, and mixing nitrate of soil and sewage or manure.

• Economic and Environmental Geology
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• v.29 no.3
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• pp.235-246
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• 1996

Placer gold in collected heavy minerals from several localities in Huongkhe area, is consistently very finegrained (${\leq}100$ to $400{\mu}m$). The size and size distribution show somewhat differences at Dongdo and Hoahai : at Dongdo, predominant relatively larger and wide distribution; at Hoahai, characteristic relatively finer and narrow distribution range. The morphology of gold grains is divided into the four groups assumed by the dimension ratio : spherical, subprismoidal, prismoidal, and irregular. The gold grains at Dongdo show wide morphological distribution, whereas, at Hoahai, spherical form is predominant (${\approx}75%$). Three main types of gold are classified based on their chemical composition and mode of occurrence: type I (electrum; fineness=568~931), type II (amalgam; fineness=671~927), and type III (native gold; fineness=923~999). Type I gold contains, relatively high and variable silver contents (${\approx}11$ to 58 atomic % Ag), and has been classified into two subtypes based on their silver contents (type IA, ${\approx}11{\sim}39$ atomic % Ag; type IB, ${\approx}40{\sim}58$ atomic % Ag). However, type I gold would have been generally original compositions of electrum which originated at the provenance deposits. Mercury reacts with gold and silver to form amalgam (type II gold) which has variable Hg contents (1.2~30.5 atomic % Hg). The mercury contents in gold grains at Hoahai (10.9~30.5 atomic % Hg) are higher than those at Dongdo (5.8~21.1 atomic % Hg). The gold grains from the area generally exhibit a high-purity gold (type III) rim. The individual rims on the various grains range from <1 to $80{\mu}m$ in thickness and have silver contents of <10 atomic percent Ag, even though the core compositions range from ${\approx}11$ to 58 atomic percent Ag. The rim of gold most likely is responsible for the commonly cited cases of gold from placer deposits assaying at higher values of fineness than the gold in the corresponding source lode. The gold-rich rim in the Huongkhe area apparently forms by a combination of self-electrorefining and preferential dissolution of silver under oxidizing nature during the weathering and transport process. All data of gold grains in the Huongkhe area suggest that the transport distances and/or time of placer gold at Hoahai are generally farther than those at Dongdo. The mercurian gold bearing provenance deposits at Dongdo and Hoahai would be suggest nearest epithermal gold-silver vein-type.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.57-65
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• 2015

As information technology fusion is accelerated, the researches to improve the quality and productivity of crops inside a plant factory actively progress. Advanced growth environment management technology that can provide thermal environment and air flow suited to the growth of crops and considering the characteristics inside a facility is necessary to maximize productivity inside a plant factory. Currently running plant factories are designed to rely on experience or personal judgment; hence, design and operation technology specific to plant factories are not established, inherently producing problems such as uneven crop production due to the deviation of temperature and air flow and additional increases in energy consumption after prolonged cultivation. The optimization process has to be set up in advance for the arrangement of air flow devices and operation technology using computational fluid dynamics (CFD) during the design stage of a facility for plant factories to resolve the problems. In this study, the optimum arrangement and air flow of air circulation fans were investigated to save energy while minimizing temperature deviation at each point inside a plant factory using CFD. The condition for simulation was categorized into a total of 12 types according to installation location, quantity, and air flow changes in air circulation fans. Also, the variables of boundary conditions for simulation were set in the same level. The analysis results for each case showed that an average temperature of 296.33K matching with a set temperature and average air flow velocity of 0.51m/s suiting plant growth were well-maintained under Case 4 condition wherein two sets of air circulation fans were installed at the upper part of plant cultivation beds. Further, control of air circulation fan set under Case D yielded the most excellent results from Case D-3 conditions wherein air velocity at the outlet was adjusted to 2.9m/s.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.282-291
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• 2006

Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.11-15
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• 1982

The growth rate and heat resistance of two types of Bacillus cereus isolated from cooked rice were observed. The FB-1 strain showed positive to haemolysis and negative to starch hydrolysis, but FB-2 strain positive to both reaction. The cell number of B. cereus FB-1 reached to more than $10^7\;cells/ml$ within 6 to 12 hours at $25{\sim}35^{\circ}C$ when cultured on the medium of cooked rice homogenate (cooked rice 30g-phosphate buffer solution 80 ml), but the numbers at its maximum growth were only $10^4{\sim}10^6\;cells/ml$ at $45{\sim}55^{\circ}C$. The specific growth rate of FB-1 strain were $0.82hr^{-1}\;at\;20^{\circ}C$, $1.76hr^{-1}\;at\;30^{\circ}C$, $2.21hr^{-1}\;at\;35^{\circ}C$ and $1.84hr^{-1}\;at\;40^{\circ}C$, respectively. D-values of FB-1 and FB-2 spores at $70{\sim}100^{\circ}C$ were in the range from 18 to 3.1 min and 23.5 to 3.7 min, respectively.

• Journal of Home Health Care Nursing
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• v.5
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• pp.84-99
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• 1998

The objectives of this study are to identify the actual educational contents of management for head nurse and to propose the educational subjects according to identity the needs of head, charge, and staff nurses. The subjects were investigated the actual Management Development Programs and educational needs of head nurses and prospective nurse manager(charge nurse, staff nurse with a lot of clinical experiences) in general hospitals. The tools were composed of two questionnaires: One was developed from the literature review for making items to measure actual situation. The other was revised Katz's model for measurement of educational needs. The first respondents of actual situation were 27 general hospitals with over 400 beds in Seoul and the second respondents were 89 head nurses, 67 charge nurses and 136 nurses at 3 hospitals by convenient sampling out of 27 general hospitals. Data were collected by telephone interview, mail questionnaire and visiting from 7th of October through 30th of November in 1997. In data analysis, general characteristics of the respondents and actual status of Management Development Programs were analyzed by frequency and percentage. Educational needs according to general characteristics were analyzed by ANOVA The results were as follows: 1. Actual situation of Management Development Program 1) Seven hospitals(26%) had Management Development Program for prospective managers and 14 hospitals (52%) for head nurses. 2) Education Department existed in 14 hospitals (52%). 3) One hospital(4%) had top level managers took part in the Management Development. 4) Two hospitals selected head nurse, who had finished courses of Management Development. Eight hospitals(30%) assessed educational needs. The assessment tools consisted of making a question via questionnaire(75%), determining at department meeting(12%) and interview(13%). 5) Educational programs had 3 types: 10 lecture type, 7 discussion type and 4 role play type programs. 6) One hospital evaluated the change of learner's attitude. 7) Four hospitals scored educational point, but that was measured only by attending. 8) Actual Management Development Programs were as follows. parenthesis indicates the number of hospitals. (1) Management Development Programs for Prospective manager. Role perception of Middle level Manager (1) . Role reconstruction of Nurse Manager (1). Workshop for Charge Nurse (1). Nursing Delivery System and Nursing Process (1). Communication (1). Motivation (1) (2) Management Development Programs for Head nurse.. Head nurse's Role (5). Administrative Work (7). Service Education (4). Prevention and Countermeasure of Nursing Incidence (3). Appraisal (3) 2. The results of needs on Management Development subject 1) The educational needs of all respondents on 3 skill domains showed positive agreement to strongly positive agreement. 2) High priority(more than 4.5) items were 12 of 24 Human skill items(50%), 1 of 6 Technical skill items(16%), and 2 of 13 Conceptual skill items (15%). 3) Out of high priority items, 8 items were instituted. 4) All respondents showed high needs on 3 skill domains regardless of 3 positions (head nurse, charge nurse, and nurse). Educational needs of Human skill domain, according to position were 108. S, 108.7, 106.8 (mean score = 72) , needs of Technical skill domain were 26.5, 26.6, 26.I(mean score=18), and needs of Conceptual skill domains were 56.9,56.7, 55.1(mean score=39). 5) Needs of 3 skill domains according to clinical career showed significant difference. Out of respondents, nurses with career of over 16years showed lowest degree of needs in Human skill domains(F=4.47, P=.004) and Conceptual skill domain(F=2.93, P=.034). 6) Educational needs according to educational background were not significant difference. But out of respondents, nurses educated at 3-year junior college relatively showed lowest needs in all of the 3 skill domains. With the above-mentioned findings, further study is necessary for generalization of this study at hospitals with different bed size and location. Also it is needed to study about management skill of nurse and charge nurse, and effective educational method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.744-751
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• 2008

Physicochemical properties of Gugija-sugar leaching were investigated by adding sugar ratio on Gugija (Lycii fructus) raw fruit. Gugija were prepared by parboiling ($40{\sim}50$ sec at $85^{\circ}C$) and unparboiling. Gugija-sugar leaching were leached after preserving (5 months at $5^{\circ}C$) Gugija-sugar mixture (20, 40, 60, 80 and 100% sugar based on raw Gugija). The yield increased with UPRGSL-4 (Gugija-sugar leaching adding 80% sugar) having the highest yield at 77.5%; in contrast, total acidity decreased with increasing ratio of sugar. The main organic acids of raw Gugija are tartaric acid (0.63%), citric acid (0.57%), malic acid (0.54%) and succinic acid (0.3%). Citric acid and succinic acid decreased with increasing ratio of sugar but malic acid and tartaric acid increased on Gugija-sugar leaching. Polyphenolics and betaine content of unparboiling Gugija-sugar leaching decreased as increase ratio of sugar but in term of used Gugija amount, betaine content of each Gugija-sugar leaching was equal to raw Gugija. Also, parboiling Gugija-sugar leaching decreased quickly with increasing ratio of sugar, especially PRGSL-4 and PRGSL-5 (parboiling Gugija-80 and 100% sugar leaching, respectively) was not determined. 15 types of free amino acids were detected in raw Gugija; the total content was 601.6 mg/100 g and the highest amino acid among them was serine, 218.1 mg/100 g. In PRGSL-4 prepared by parboiling, 9 kinds of free amino acid were detected and the total content was 383.3 mg/100g. Also, in UPRGSL-4 (unparboiling Gugija-80% sugar leaching), all 17 kinds were detected and its total content was 705.7 mg/100 g.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.113-126
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• 2002

Background : DNA repair plays a crucial role in protection from cancer-causing agents. Therefore, a reduced DNA repair capacity can increase the susceptibility to lung cancer. The XPC gene contains 15 exons and encodes a 940 amino acid protein that plays a central role in DNA damage recognition of the nucleotide excision repair pathway, which is a major DNA repair mechanisim removing the bulky-helix distorting DNA lesions caused by smoking. Recently several polymorphisms in the XPC gene were identified. In addition, it is possible that these polymorphisms may affect the DNA repair capacity, which modulate cancer susceptibility. The relationship between codon 499 and 939 polymorphisms, and a poly(AT) insertion/deletion polymorphism in the XPC gene, and the lung cancer risk were investigated. Materials and Methods : The genotypes were determined using either PCR or PCR-RFLP analysis in 219 male lung cancer patients and 150 healthy males controls. Results : The frequencies of the genotypes (Val499Ala, PAT and Lys939Gln) among the cases were not significantly different from those of the controls. There was no significant associantion between these polymorphi는 and the lung cancer risk when the analyses were stratified according to age, smoking status and the pack-years of smoking. Moreover, the genotypes had no apparent relationship with any of the histological types of lung cancer. There was a linkage disequilibrium among the Val499Ala, PAT and Lys939Gln polymorphisms. The PAT polymorphism had a strong linkage disequilibrium with the Lys939Gln polymorphism (kappa value=0.87). The XPC haplotypes showed no significant association with the lung cancer risk. Conclusion : These results suggest that XPC Val499Ala, PAT and Lys939Gln polymorphisms are not major contributors to the individual lung cancer susceptibility in Koreans.

• KDI Journal of Economic Policy
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• v.32 no.2
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• pp.171-216
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• 2010

With the payment and settlement systems becoming more and more complex and interconnected, the issue of their interdependency rises as an important academic issue as well as a policy topic. This study examines causes, forms, and risk management of interdependencies of payment and settlement systems in Korea, and presents their current situation. By way of simulations using BOF-PSS2 developed by the Bank of Finland, we quantify the effects of an operational disruption on the payment and settlement systems so as to figure out the degree of interdependency. As a result, the secondary round effect reaches up to ￦13.6 trillion a day, which amounts to 7.8% of the daily settlement value. Furthermore, if we also consider the amount of direct operational disruption, the volume of operational disruption occupies 22.3% of total value of the daily settlement, evidencing that the interdependencies of the payment and settlement systems in Korea is enormously widespread. The secondary round effects are found to be more severe with security companies rather than with banks, and to be more depended upon when it is perceived rather than it actually happens. In case that we expand the liquidity to include cash holdings and deposits as assets, the secondary round effect dramatically decreases in all types of financial institutions while foreign banks account for more share of all the secondary round effects increases. Based on these results, we suggest various policy tasks and directions to improve the risk management of settlement systems: expansion of off-setting settlements, introduction of a new settlement system for securities transactions, rapid provision of liquidity to financial institutions, more effective monitoring on participant institutions, and intensified information sharing and cooperation among the systems.

• Food Science and Preservation
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• v.22 no.3
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• pp.392-398
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• 2015

The physicochemical properties of spray-dried rice flour with Lactobacillus plantarum CGKW3 were investigated. Amylose and damaged starch contents of spray-dried rice flour (S10, S20, S30, and S50) with L. plantarum CGKW3 were 14.18~17.75% and 24.65~34.08%, respectively. The particle size of spray-dried rice flour was $82.28{\sim}131.17{\mu}m$. The rice flour with L. plantarum CGKW3 showed a good powder flowability. The water absorption and water solubility of spray-dried rice flour were 1.96~2.13 and 9.91~21.95%, respectively. Thermal properties measured by differential scanning calorimeter revealed that the enthalpy (${\Delta}H$) for starch gelatinization were highest in the rice flour (S50) with L. plantarum CGKW3. When compared, the viable cell number of spray-dried rice flour were found to be in the following order: S10 (5.78 log CFU/g) < S20 (6.38 log CFU/g) < S30 (6.69 log CFU/g) < S50 (7.11 log CFU/g). The survaival rate of L. plantarum CGKW3 was 60.02-73.85%, which reflected the improvement in the quality of rice flour with an increase in treatment concentration. Based on our results, spray-dried rice flour with L. plantarum CGKW3 could be used in various types of rice foods.