• Journal of Environmental Health Sciences
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• v.40 no.3
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• pp.215-224
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• 2014

Objective: This study was carried out in order to determine the depositional characteristics of pine needles, pine bark, and soil used as a passive air sampler (PAS) for atmospheric polybrominated diphenyl ethers (PBDEs). Methods: All three media were sampled from the same site. The PBDE concentrations were analyzed by HRGC/HRMS, and the lipid contents were measured using the gravimetric method by n-hexane extraction. Results: The total PBDE concentration was the highest in soil (22,274.57 pg/g dry), followed by pine bark (20,266.39 pg/g dry), and then pine needles (7,380.22 pg/g dry). Pine needles contained the highest lipid contents (21.31 mg/g dry), whereas soil (10.01 mg/g dry), and pine bark (4.85 mg/g dry) contained less. There were poor correlations between lipid content and total PBDE concentrations in the media ($R^2$=0.8216, p=0.2814). Congeners BDE 47, 99, 183, 196, 197, 206, 207 and 209 showed peak concentrations. Among these, BDE 206, 207, and 209 are highly brominated PBDEs that exist as particulates in ambient air. They accounted for 81.2% [69.2 (pine needles) - 89.0% (tree bark)] of the concentration and therefore are noted as the main congener of the total PBDEs. Conclusions: It can therefore be concluded that for reducing error by improper sampling, the same species of media should be recommended for use as a PAS for atmospheric PBDEs due to the differences in depositional characteristics.

• Journal of Korean Society for Quality Management
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• v.47 no.3
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• pp.497-508
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• 2019

Purpose: The purpose of this study is to overcome limitations of conventional studies that to predict Baltic Dry Index (BDI). The study proposed applications of Artificial Neural Network (ANN) named Long Short-Term Memory (LSTM) to predict BDI. Methods: The BDI time-series prediction was carried out through eight variables related to the dry bulk market. The prediction was conducted in two steps. First, identifying the goodness of fitness for the BDI time-series of specific ANN models and determining the network structures to be used in the next step. While using ANN's generalization capability, the structures determined in the previous steps were used in the empirical prediction step, and the sliding-window method was applied to make a daily (one-day ahead) prediction. Results: At the empirical prediction step, it was possible to predict variable y(BDI time series) at point of time t by 8 variables (related to the dry bulk market) of x at point of time (t-1). LSTM, known to be good at learning over a long period of time, showed the best performance with higher predictive accuracy compared to Multi-Layer Perceptron (MLP) and Recurrent Neural Network (RNN). Conclusion: Applying this study to real business would require long-term predictions by applying more detailed forecasting techniques. I hope that the research can provide a point of reference in the dry bulk market, and furthermore in the decision-making and investment in the future of the shipping business as a whole.

• Animal Bioscience
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• v.35 no.5
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• pp.778-788
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• 2022

Objective: The objective of the study was to understand and document socio-economic characteristics, production parameters, challenges and management practices used by Fijian households which keep indigenous chickens. Methods: A survey involving 200 households was carried out in coastal and inland communities of Fiji's wet and semi-dry ecoregions. Data on the influence of ecoregion and location of households relative to the sea on management practices, challenges and productivity of indigenous chickens were analyzed using logistic regression and general linear model of SAS software. Results: Irrespective of location relative to the sea and ecoregion, households indicated that they kept indigenous chickens for food and income generation. The Welsummer was the most (p>0.05) preferred breed. Households in the semi-dry inland communities had the largest (p<0.05) flocks compared to those in semi-dry coastal communities and the wet region. Chickens in the semi-dry region performed better (p<0.05) than those in the wet region in terms of number of clutches per year and mature live weight. Predators and feed shortages were the biggest challenges faced by households in all areas. The mongoose was ranked as the most (p>0.05) common predator followed by domestic dogs. Most households in the wet ecoregion's coastal communities housed their chickens at night, whereas communities in semi-dry ecoregion housed their chickens most of the time (p<0.05). In all regions, no households sold their chickens to commercial markets (p>0.05). Households in semi-dry ecoregion were more likely (p>0.05) to sell their chickens at the local market place. Conclusion: The productivity of local chickens in Fiji is low because of feed shortage, predators such as the mongoose and lack of market linkages.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.538-546
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• 2008

Large-type goats eating dry forage secreted large volumes of saliva which resulted in the loss of $NaHCO_3$ from the blood and decreased plasma volume (hypovolemia). This research investigated whether or not the loss of $NaHCO_3$ from the blood and hypovolemia brought about by dry forage feeding actually depresses feed intake in large-type goats under free drinking conditions. The present experiment consisted of three treatments (NI, ASI, MI). All treatments in this experiment were carried out under free drinking conditions. In the NI control (NI), a solution was not infused. In the ASI treatment, i.v. infusion of artificial saliva was initiated 2 h before feeding and was continued for a total of 3 h concluding 1 h after the commencement of the feeding perod. In the MI treatment, mannitol solution was infused to replenish only water lost from the blood in the form of saliva. The hematocrit and plasma total protein concentrations during feeding in the NI control were observed to be higher than pre-feeding levels. This indicated that dry forage feeding-induced hypovolemia was caused by the accelerated secretion of saliva during the initial stages of feeding in freely drinking large-type goats. Increases in hematocrit and plasma total protein concentrations due to dry forage feeding were significantly suppressed by the ASI treatment. While hematocrit during feeding in the MI treatment was significantly lower than the NI control, plasma total protein concentrations were not different. From these results, it is clear that the MI treatment was less effective than the ASI treatment in mitigating the decreases in plasma volume brought about by dry forage feeding. This indicates that plasma volume increased during dry forage feeding in the ASI treatment which inhibited production of angiotensin II in the blood. The ASI treatment lessened the levels of suppression on dry forage feeding, but the MI treatment had no effect on it under free drinking conditions. The results indicate that despite the free drinking conditions, increases in saliva secretion during the initial stages of dry forage feeding in large-type goats caused $NaHCO_3$ to be lost from the blood into the rumen which in turn caused a decrease in circulating plasma volume and resulted in activation of the renin-angiotensin system and thus feeding was suppressed.

• Journal of Korean society of Dental Hygiene
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• v.15 no.1
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• pp.55-62
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• 2015

Objectives: The purpose of this study was to investigate the associated factors of self-reported dry mouth in adults. Methods: A self-reported questionnaire was filled out by 249 adults in Seoul and Gyeonggi-do from June to October, 2014. The questionnaire consisted of general characteristics of the subjects, age, monthly income, smoking, alcohol drinking, and systemic diseases including systemic diseases, medication, oral health status, and stress. The question for dry mouth consisted of dryness in skin, eyes, lips, and nasal mucosa. The subjective dry mouth consisted of 6 questions measured by visual analogue scale(VAS). Cronbach's alpha was 0.881 in the study. Oral health related quality of life (OHIP-14) was adapted from Yoon. The questionnaire for OHIP-14 included functional limitation, physical pain, psychological disability, social disability, and experience in hadicap measured by Likert 5 scale. Cronbach's alpha was 0.885 in the study. Data was analyzed for a t-test, one-way ANOVA and multiple regression analysis by using SPSS(SPSS 18.0, USA) program. Results: There were positive correlations between oral health-related quality of life and self-reported dry mouth (functional limitation r=0.288, physical pain r=0.219, psychological discomfort r=0.193, physical disability r=0.280, psychological disability r=0.205, social disability r=0.224 and handicap r=0.270). In the multiple regression analysis, variation of self-reported dry mouth were positively associated with dry eyes{very often(${\beta}=0.305$)), sometimes(${\beta}=0.186$)}, dryness on lips{very often(${\beta}=0.247$), sometimes(${\beta}=0.177$)}, handicap(${\beta}=0.152$), physical disability(${\beta}=0.128$) and alcohol drinking(1-2 times/week)(${\beta}=0.116$) (p<0.001). Conclusions: Self-reported dry mouth may cause deterioration of the entire body dryness(dryness on eyes and lips), low oral health-related quality of life(handicap and physical disability) and alcohol drinking. Thus, It is necessary to develop oral health education programs to prevent and manage dry mouth in adults.

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.101-109
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• 2012

Wood composites are a hygroscopic material and have ability to exchange its moisture content with air. This study investigated the formaldehyde emission and moisture content change of four wood composites (particleboard (PB), medium density fiberboard (MDF), high density fiberboard (HDF), laminated HDF (L-HDF)) as a function of bake-out temperature and time. The composites were baked out for 1, 3, 5, 7, 10, 14, 21, and 28 days at temperatures of $20{\pm}2$, $35{\pm}2$, and $50{\pm}2^{\circ}C$ in a dry oven. The moisture content change was used to determine the emission bake-out of the composites. Best bake-out time results were obtained with after 7 days all composites. Formaldehyde emission values of composites decreased with decreasing moisture content for both temperatures. The formaldehyde emission results of bake-out temperature 35 and $50^{\circ}C$ showed a similar tendency.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.735-744
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• 2003

The field observations on a seasonal characteristic of organic matter and its origin in the surface sediment were carried out at 35 stations in Deukryang bay, southern coast of Korean Peninsula from May 1995 to February 1996. The analytical parameters were mud temperature, ignition loss(IL), chemical oxygen demand(COD), pheopigment, sulfide and water content. The origin and seasonal dynamics of organic matter in Deukryang Bay were analyzed by COD/IL, COD/sulfide ratio and principal component analysis(PCA). As a results of the mud temperature fluctuated between 2.1$^{\circ}C$ with the lowest mean 4.6$^{\circ}C$ in winter and 27.6$^{\circ}C$ with the highest mean 25.5$^{\circ}C$ in summer. The range of ignition loss(IL) was from 3.1% in autumn to 21.5% in winter. Chemical oxygen demand(COD) showed the highest mean value of 8.45 mg/g dry in spring within the range of 2.90∼18.21 mg/g dry, while it showed the lowest value of 4.33 mg/g dry in autumn within the range of 0.67∼10.37 mg/g dry. Pheopigments showed the highest mean value of 9.04 $\mu\textrm{g}$/g dry in autumn within the range of 1.36∼20.44 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 2.20 $\mu\textrm{g}$/g dry in summer within the range of 0.33∼11.36 $\mu\textrm{g}$/g dry. The range of total sulfide (H$_2$S) was from no detect(ND) to 3.30 mg/g dry in spring. And water content showed the annual mean value of 43.6% within the range of 23.6∼54.9%. The source of organic matter by COD/IL and COD/sulfide ratio in Deukryang Bay had been producted by primary producer in sea water areas except the areas effected by small stream, domestic and animal wastes. And the analytical results of PCA was able to be divided into three different regions. The former was characterized by the shallow depth and authigenic organic matter from phytoplankton in northwest area and northeastern inner bay, the secondary was done by deeper depth and allochthonous one from lands in southeast area and eastern entrance of bay, and the latter was done by authigenic one from the farm of seaweeds such as, sea cabbage, sea mustard etc in western entrance of bay. But a study on the relationship between sulfide and COD concentration in the northeastern inner bay which was characterized by the water stagnation will to take much more studying including major constituents of organic matter in the future.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.2
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• pp.93-102
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• 1979

Chemical compositions of Flue - cured and Burley tobacco leaf and smoke were analyzed to find out simple correlation between compositions. Based on the simple correlation ( $r$ ) data, four regression equations were obtained for dry condensate and nicotine in smoke as follows, $Y_{FT}=\;0.816+4.638X_1+0.346X_2$......................................(1) $Y_{BT}=\;0.235+0.884X_3-0.088X_4$......................................(2) $Y_{FN}=\;0.015+0.090X_5+0.476X_1$......................................(3) $Y_{BN}=-0.026+0.101X_3-0.006X_4$.........................................(4) where, $Y_{FT}$ : dry condensate (mg/cig.) in cigarette smoke of Flue-cured $Y_{BT}$ : dry condensate (mg /cig. ) in cigarette smoke of Burley $Y_{FN}$ : nicotine contents (mg/cig.)in cigarette smoke of Flue-cured $Y_{BN}$ : nicotine contorts (mg/cig. ) in cigarette smoke of Burley $X_1$ : total alkaloid contents (%) of Flue-cured $X_2$ : curde ash contents (%)of Flue -cured $X_3$ : alcohol -benzene extract contents (%) of Burley $X_4$ : curde ash contents (%) of Burley $X_5$ : hexane extract content (%) of Flue -cured Standard deviation for regressions equations were obtained respectively. equation(1),$\pm$3.16 : equation (2),$\pm$1.94 : equation (3),$\pm$0.35 , equation (4) $\pm$ 0.33. Regression equations between dry condensate and nicotine contorts in cigarette smoke were also obtained in the forms of equation(5) and(6) $Y_{FN}$= 0.274 $Y_{FT}$- 3.259............................(5) $Y_{BN}$= 0.249 $Y_{BT}$ - 2.093.............................(6) Standard deviations, $\pm$ 0.061 and $\pm$ 0.152, were obtained for regression equation(5) and (6) respectively.

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.403-409
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• 1993

In this paper, an $NH_3$, added during dry oxidation and annealing m Si( 111) is clarified effect ive to suppress or remove defects. Annealing effects in $N_2$ and $NH_3/N_2$ ambient are estimated with dry $O_2$ and $NH_4$ oxidation($NH_3$ added in dry $O_2$ oxidation) method. C;em'rated defects in dry $O_2$ oxidation are lengthened according to oxidation time. but any defects in $NH_3$ oxidation are not found. Dry oxidation, after $NH_3$ oxidation as an initial oxidation. lias the defect -removing effect at the interface of Si -$SiO_2$. After dry or $NH_3$. oxidation. the annealmg 7.5% $NH_3/N_2$ ambient brings out gettering effect of OSF. The annealing in 7.5% $NH_3/N_2$ ambient for NI L oxidation method decreaSE,s $NH_3$ length of OSF about 20 % compared with dry oxidation method. Tlw feature of OSF is pit type, the gettering is directed to (011) plane for (111) plane. and OSFs are etched following to 110) directIon.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.89-99
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• 2011

This study was carried out to investigate effect of irradiation doses on quality of vacuum-packed dry-cured ham during storage. Dry-cured pork slices were vacuum-packaged in nylon/ polyethylene bags. Vacuum-packed dry curd pork was stored at $10{^{\circ}C}$ for 12 weeks after irradiation (0 kGy, 2.5 kGy, 5 kGy, 7.5 kGy and 10 kGy) and physicochemical properties of dry curd porks, such as meat color surface, thiobarbituric aicd reactive substances, volatile basic nitrogen, pH, microbial (total plate count, Lactobacillus) and sensory properties (color, flavor, overall acceptability) were investigated. Irradiation treatment decreased a*-value, TPC and Lactobacillus. Irradiation dose significantly (p<0.05) increased irradiation flavor and TBA value. However, irradiation dose decreased redness and sensory color in dry-cured ham. The quality of dry-cured ham was affected by the irradiation dose. The results suggested that dry-cured ham irradiated at 5 kGy dose may show optimum quality characteristics of the products as well as microbial safety.