• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.170-175
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• 1980

A mass production of chestnut necessiates the development of economic long-term storage method. The main objective of this study was to confirm the technical aspect of the chestnut storage method which was developed by two year project and to review the method of commercial application. The chestnut used for the experiments were separated in brine $(5.5{\sim}6.0^{\circ}\:B{\acute{a}}ume)$ into matured and unmatured lots and fumigated with $CS_2$ at a 5 $lb/27\;m^3$ level for $25{\sim}30\;hrs.$ The chestnuts were packed in wooden boxes with sawdust (50% moisture) in the ratio of 1 : 1 by volume. The boxes were stored in the cold room $(1{\pm}1^{\circ}C,\;85{\sim}95%\;RH)$ and the cellar ($0{\sim}10^{\circ}C$, controlled only by circulating night cool air). The results obtained were as follows: 1. Fully matured chestnut could be successfully preserved $8{\sim}9\;months$ at a l0% decay level in the cold room and $4{\sim}5\;months$ months in cellar. 2. Immatured chestnuts wire inferior to the matured in storage stability. At the maximum storage period, its storage life was two months shorter. 3. The heat transfer equation of piled chestnuts with sawdust can be suggested as $T_{\infty}-T_0=(T_{\infty}-T_0){\cdot}10^{-t/320}$ and j and $f_h$ values were 1 and 320 min, respectively. 4. The chestnuts in the package of storage unit had longer shelf life than naked chestnut during the retail distribution at ambient temperature.

• 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.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.225-230
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• 2004

Jeju native sorghums were grown with six different planting densities ($5{\times}5cm,\;10{\times}10cm,\;15{\times}15cm,\;20{\times}20cm,\;25{\times}25cm\;and\;30{\times}30cm$) from April 3 to September 6 in 2000 in Jeju island to determine the influence to growth, yield and feed value by the planting densities. Days to heading were delayed from 66 days to 69 days as increasing of plant density. Plant height was 195.1cm at $30{\times}30cm$ plot, whereas that was 216.5cm at $10{\times}10cm$ plot, indicating that the plant was higher by the decrease of the planting density. As plant density increased, the number of leaves and steam diameter were decreased. Fresh forage yield increased from 25.4 to 61.3 MT/ha, dry matter (DM) yield from 5.8 to 16.5 MT/ha, crude protein (CP) yield from 0.4 to 1.5 MT/ha and total digestible nutrients (TDN) yield from 2.7 to 8.8 MT/ha as planting density from $30{\times}30cm\;to\;10{\times}10cm$ plot. Crude protein content increased from 7.0 to $9.0\%$, ether extract content from 1.7 to $4.4\%$, nitrogen free extract content from 36.9 to $38.4\%$ and TDN content from 46.1 to $55.5\%$ as planting density was decreased. whereas crude fiber content decreased from 43.9 to $37.1\%$ and crude ash content from 8.4 to $6.8\%$.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.319-337
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• 2010

Major objective of this study was to determine interannual and seasonal water quality along with characteristics of longitudinal gradients along the reservoir axis of the riverine zone (Rz)-to-lacustrine zone (Lz). Water quality dataset of five years during 2003~2007 used here were obtained from Ministry of Environment, Korea and ten physical, chemical and biological parameters were analyzed in the study. Similarity analysis, based on moropho-hydrological variables of reservoir surface area, watershed area, total inflow, and outflow, showed that the reservoirs were categorized as three groups of large-dam reservoirs (Chungju Reservoir, Daecheong Reservoir and Soyang Reservoir), mid-size reservoirs (Andong Reservoir, Yongdam Reservoir, Juam Reservoir and Hapcheon Reservoir), and small-size reservoirs (Hoengseong Reservoir and Buan Reservoir). According to the data comparison of high-flow year (2003) vs. lowflow year (2005), dissolved oxygen (DO), pH, biological oxygen demand (BOD), suspended solids (SS), total nitrogen (TN), total phosphorus (TP), chlorophyll-a (CHL) and electrical conductivity (EC) declined along the longitudinal axis of Rz to Lz and water transparency, based on Secchi depth (SD), increased along the axis. These results indicate that transparency was a function of Values of pH, DO, SS, SD, and EC at each site were greater in the low-flow year (2005) than the high-flow year (2003), whereas values of BOD, COD, TN, TP and CHL were greater in the high-flow year (2003). When values of TN, TP, CHL and SD in nine reservoirs were compared in the three zones of Rz, Tz, and Lz, values of TN, TP and CHL declined along longitudinal gradients and SD showed the opposite due to the sedimentation processes from the water column. Values of TN were not statistically correlated with TP values. The empirical linear models of TP-CHL and CHL-SD showed significant (p<0.05, $R^2$>0.04). In the mid-size reservoirs, the variation of CHL was explained ($R^2$=0.2401, p<0.0001, n=239) by the variation of TP. The affinities in the correlation analysis of mid-size reservoirs were greater in the CHL-SD model than any other empirical models, and the CHL-SD model had an inverse relations. In the meantime, water quality variations was evidently greater in Daecheong Reservoir than two reservoirs of Andong Reservoir and Hoengseong Reservoir as a result of large differences of water quality by long distance among Rz, Tz and Lz.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.233-238
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• 2007

To assess pollutant loads in Nakdong river from highland agriculture in Kyungbuk province we. analyzed water qualities such as BOD, COD, T-N, T-P and SS in year 2005. BOD values in rainy period (June and July) were relatively higher than those in dry period, and those in 4 sites among 17 sites ranged from 10.71-19.25 mg/L which exceeded water criteria (8 mg/L) for agricultural use. COD values showed similar trends like BOD values. These trends might be caused by outflow of nutrients applied in agricultural lands. T-N content ranged from 0.1 to 14 mg/L. Those in lower reaches of stream were greater in those in upper stream. Compared to T-N contents during non-farming season, T-N content in farming season were higher. These phenomenon could be due to continuous input of nutrients from small watercourses. Averaged T-P content in lower stream during farming season was 0.4 mg/L, which was eight times higher than the limiting level for algae occurrence (0.05 mg/L). BOD, T-P, T-N loads from alpine agricultural practices were 12.25 $kg/km^2{\cdot}day$, 0.55 $kg/km^2{\cdot}day$ and 32.35 $kg/km^2{\cdot}day$, respectively. These values were greater than those from forestry. Therefore, Best management Practices (BMP) for alpine agricultural field are needed to reduce pollutant loads in Nakdong river.

• Journal of the Korea Society of Computer and Information
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• v.8 no.2
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• pp.51-56
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• 2003

The structuring of Web information supports a strong user side viewpoint that a user wants his/her own needs on snooping a specific Web site. Not only the depth first algorithm or the breadth-first algorithm, but also the Web information is abstracted to a hierarchical structure. A prototype system is suggested in order to visualize and to represent a semantic significance. As a motivating example, the Web test site is suggested and analyzed with respect to several keywords. As a future research, the Web site model should be extended to the whole WWW and an accurate assessment function needs to be devised by which several suggested models should be evaluated.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.128-137
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• 2005

In this study we measured the amount of light energy that was projected through the tooth material and analyzed the degree of polymerization by measuring the surface hardness of composites. For polymerization, Optilux 501 (Demetron, USA) with two types of light guide was used: a 12 mm diameter light guide with 840 nW/$cm^2$ light intensity and a 7 mm diameter turbo light guide with 1100 nW/$cm^2$. Specimens were divided into three groups according to thickness of penetrating tooth (1 mm, 2 mm, 0 mm). Each group was further divided into four subgroups according to type of light guide and curing time (20 seconds, 40 seconds). Vickers' hardness was measured by using a microhardness tester. In 0 mm and 1 mm penetrating tooth group, which were polymerized by a turbo light guide for 40 seconds, showed the highest hardness values. The specimens from 2 mm penetrating tooth group, which were polymerized for 20 seconds, demonstrated the lowest hardness regardless of the types of light guides (p < 0.05). The results of this study suggest that, when projecting tooth material over a specified thickness, the increase of polymerization will be limited even if light intensity or curing time is increased.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.5
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• pp.482-488
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• 2014

This paper aims to analyze user's emotion automatically by analyzing Twitter, a representative social network service (SNS). In order to create sentiment analysis models by using machine learning techniques, sentiment labels that represent positive/negative emotions are required. However it is very expensive to obtain sentiment labels of tweets. So, in this paper, we propose a sentiment analysis model by using self-training technique in order to utilize "data without sentiment labels" as well as "data with sentiment labels". Self-training technique is that labels of "data without sentiment labels" is determined by utilizing "data with sentiment labels", and then updates models using together with "data with sentiment labels" and newly labeled data. This technique improves the sentiment analysis performance gradually. However, it has a problem that misclassifications of unlabeled data in an early stage affect the model updating through the whole learning process because labels of unlabeled data never changes once those are determined. Thus, labels of "data without sentiment labels" needs to be carefully determined. In this paper, in order to get high performance using self-training technique, we propose 3 policies for updating "data with sentiment labels" and conduct a comparative analysis. The first policy is to select data of which confidence is higher than a given threshold among newly labeled data. The second policy is to choose the same number of the positive and negative data in the newly labeled data in order to avoid the imbalanced class learning problem. The third policy is to choose newly labeled data less than a given maximum number in order to avoid the updates of large amount of data at a time for gradual model updates. Experiments are conducted using Stanford data set and the data set is classified into positive and negative. As a result, the learned model has a high performance than the learned models by using "data with sentiment labels" only and the self-training with a regular model update policy.

• Journal of Oral Medicine and Pain
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• v.34 no.4
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• pp.379-385
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• 2009

The purpose of this study was to present basic data that is needed in comprehension of dysesthesia after mandibular nerve injury and grasp meaning. We analyzed medical records of 59 patients who were diagnosed as dysesthesia after mandibular nerve injury from January 2007 to July 2009. The results are summarized as follows. 1. The most frequent cause was implant surgery (59%) and the most frequent injured branch of mandibular nerve was inferior alveolar nerve(81%). 2. The period passed after nerve injury showed significant interrelationship with level of pain. Visual Analogue Scale(VAS) increased from 4.82 to 6.91 after 6 month. 3. The period passed after nerve injury did not show significant interrelationship with recovery of dysesthesia. But, when conservative treatment was offered at earlier stage, ratio of patients who showed recovery of symptom tended to increase. 4. In computed tomography, level of invasion into inferior alveolar nerve canal did not show significant interrelationship with level of pain and recovery of dysesthesia. Conclusively, in the patients with dysesthesia of mandibular nerve, inferior alveolar nerve injury by dental implant surgery dominated most significant problem. Although level of invasion into inferior alveolar nerve is the most important factor to initiation of dysesthesia, there are other various factors exert more influence on the level of pain or recovery of dysesthesia. Therefore, begining conservative therapy at earlier stage is encouraged. Also, because nerve injuries can occur without direct invasion into nerve canal, so leaving enough safe space from nerve canal is needed for prevention of indirect nerve injury.

• Journal of agricultural medicine and community health
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• v.36 no.4
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• pp.227-237
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• 2011

Objectives: This study was conducted to investigate the utilization and its determinants of rehabilitation services of people with disabilities in a rural area. Methods: From March 2 to April 1, 2011, we interviewed 101 disabled people with either physical disabilities or brain lesions. The subjects completed questionnaires about the utilization of rehabilitation services, general characteristics (age, sex, marital status, education level, economic status, health insurance, housing, and employment) and disability characteristics (type, level, comorbidity, reason for the occurrence of the disability, self-rated degree of disability, and daily life care giver). Frequency, Pearson's chi-square test, and a multiple logistic regression were used for statistical analysis. Results: This study showed that 70.3% of the people in this rural area with disabilities were using rehabilitation services. The two most common reasons for not using the services were "doubt about the effectiveness of the service" and "no facilities nearby." The facilities that the disabled people were currently using, in the order of most used to least, were general hospitals or clinics, rehabilitation centers, oriental medicine clinics, and public health centers. Only 19.7% of those who received rehabilitation responded that they were satisfied with the service. Significant factors in the utilization of rehabilitation services were sex, employment, self-rated economic status, and the reason for the occurrence of the disability. Women, people who were currently working, people who were of middle or higher economic status, or people who had acquired a disability were significantly more likely to use the services. Conclusions: A large number of people with disabilities in a rural area use rehabilitation services at present, but accessibility and satisfaction were low. Quantitatively and qualitatively, rehabilitation services for disabled people in a rural area should be centered around Community-based Rehabilitation (CBR). Effective strategies, for example reaching those who have not used the rehabilitation services, will be needed to improve services in rural areas.