• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.561-572
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• 2008

Responses of real-time control parameters, such as ORP, DO and pH, to the conditions of biological animal wastewater treatment process were examined to evaluate the stability of real-time control using each parameter. Also an optimum index for supplemental carbon source addition based on NOx-N level was determined under a consideration of denitrification rate by endogenous respiration of microorganism and residual organic matter in liquor. Experiment was performed with lab-scale sequencing batch reactor(SBR) and working volume of the process was 45L. The distinctive nitrogen break point(NBP) on ORP-and DO-time profiles, which mean the termination of nitrification, started disappearing with the maintenance of low NH4-N loading rate. Also the NBP on ORP-and DO-time profiles was no longer observed when high NOx-N was loaded into the reactor, and the sensitivity of ORP became dull with the increase of NOx-N level. However, the distinctive NBP was constantly occurred on pH(mV)-time profile, maintaining unique profile patterns. This stable occurrence of NBP on pH(mV)-time profile was lasted even at very high NOx-N:NH4-N ratio(over 80:1) in reactor, and the specific point could be easily detected by tracking moving slope change(MSC) of the curve. Revelation of NBP on pH(mV)-time profile and recognition of the realtime control point using MSC were stable at a condition of over 300mg/L NOx-N level in reactor. The occurrence of distinctive NBP was persistent on pH(mV)-time profile even at a level of 10,000mg/L STOC(soluble total organic carbon) and the recognition of NBP was feasible by tracing MSC, but that point on ORP and DO-time profiles began to disappear with the increase of STOC level in reactor. The denitrfication rate by endogenous respiration and residual organic matter was about 0.4mg/L.hr., and it was found that 0.83 would be accepted as an index for supplemental carbon source addition when 0.1 of safety factor was applied.

• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.65-74
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• 2009

It is expected that the number of apartment complexes in Korea that are over 20 years old will rapidly increase to more than 3,500,000. Consequently, the remodeling of these buildings is being revitalized throughout the country. Among the requirements for such remodeling, the expansion of parking lots has considerable weight. When enlarging a parking lot, the access route from an underground floor to the main building (i.e., the means of entry into the main building) determines the possibility of vertical enlargement for elevators, the size of the parking lot, the construction period, and construction expenses, etc. When enlarging an underground parking lot of an apartment complex, the access between the main building and the parking lot, as well as the inhabitants' requirements for entering the main building, are generally determined based on the designer's experience, rather than on the exact estimation of the peculiarity of the complex. In order to resolve such a problem, when enlarging an underground parking lot, a systematic and rational method is needed for selecting the means of entry into the main building. In this study, a selection model is derived for the method of selecting an access route into the main building when constructing an underground parking lot, in order to provide a reasonable decision-making process. A research method was investigated for determining the access route into the main building when enlarging a parking lot. On the basis of research carried out through in-depth interviews with experts, the characteristics for each means of entry into the main building were analyzed and the factors affecting the selection of the access route were deduced. The affecting factors selected were construction efficiency, convenience efficiency and economic efficiency. Weight values were then estimated for the selected affecting factors by applying the AHP method. Results showed that convenience efficiency, which gained the highest value, is the most important factor in selecting the means of entry into the main building. The most suitable means of entry into the main building was also suggested after estimating the applicability of the site by selecting complexes with remodeling possibility. This study will be applied as a reference for selecting the means of entry into the main building when constructing an underground parking lot particularly for older apartment complexes.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.60-66
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• 2005

When external pressure higher than osmosis pressure is reversely derived into solution, its solvent is moved into the solution having lower concentration, which is called 'reverse osmosis'. We investigated the desalination application of deep ocean water using reverse osmosis pressure of $40-70\;kgf/cm^2$ We observed how to operational factor j like flow rate, water temperature and pressure have effect on efficiency of reverse osmosis membrane and salts rejection. Fluxes of reverse osmosis membrane are directly proportional to water temperature and pressure. However, salts rejection rates are positively correlated with pressure and inversely proportional to water temperature. Separation efficiencies of osmosis membrane for major elements such as $Mg^{2+},\;Ca^{+2},\;Na^+\;and\;K^+$ are as follows in a strong electrolysis solution like seawater; $Ca^{2+},\;Mg^{2+}>K^+>Na^+$. Rejection rates of $Mg^{2+}\;and\;Ca^{2+}$ that have high electric charges are over 99% and show positively correlation with water temperature. Rejection rates of $Na^+$ having low electric charge is observed to be 98%-99%, which rates is much lower than those of $2^+$ charged ions like $Ca^{2+}\;and\;Mg^{2+}$. Ion rejection rates of boron, B, are much low because boron is present il free state or gas phase in seawater. Boron concentration in desalination water is over criteria of Korean drinking water, 0.3 mg/L. However, we could satisfied with the criteria of drinking water under the operation condition like temperature $5^{\circ}C$ and pressure $70kgf/cm^2$, using the relationship that rejection rates of boron is proportional to pressure and is inversely proportional to water temperature

• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.1-9
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• 2015

Compton cameras overcome several limitations of conventional mechanical collimation based gamma imaging devices, such as pin-hole imaging devices, due to its electronic collimation based on coincidence logic. Especially large-scale Compton camera has wide field of view and high imaging sensitivity. Those merits suggest that a large-scale Compton camera might be applicable to monitoring nuclear materials in large facilities without necessity of portability. To that end, our research group have made an effort to design a large-scale Compton camera for safeguard application. Energy resolution or position resolution of large-area detectors vary with configuration style of the detectors. Those performances directly affect the image quality of the large-scale Compton camera. In the present study, a series of Geant4 Monte Carlo simulations were performed in order to examine the effect of those detector parameters. Performance of the designed large-scale Compton camera was also estimated for various monitoring condition with realistic modeling. The conclusion of the present study indicates that the energy resolution of the component detector is the limiting factor of imaging resolution rather than the position resolution. Also, the designed large-scale Compton camera provides the 16.3 cm image resolution in full width at half maximum (angular resolution: $9.26^{\circ}$) for the depleted uranium source considered in this study located at the 1 m from the system when the component detectors have 10% energy resolution and 7 mm position resolution.

• Journal of Life Science
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• v.20 no.7
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• pp.1078-1085
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• 2010

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are bioaccumulative chemicals that are considered to be toxic contaminants based on several epidemiological studies. These chemicals in colostrum were investigated and estimated for their residual consistencies by maternal characteristics like parity and maternal ages. Test subjects were healthy primipara and multipara mothers with a mean age of 31.5 (S.D=3.6) in 2007. Seven isomers of PCDDs, 10 of PCDFs, 4 of non-orthopolychlorinated biphenyls(non-ortho PCBs) and 8 of mono-orthochlorinated polychlorinated biphenyls (mono-ortho PCBs) were analyzed by HRGC/HRMS. From the analyzed data, the mean level of total WHO-TEQs was 9.41 pg TEQ/g lipid, which is significantly lower than the level found in individuals from other countries. The main contributors to the total WHO-TEQs with increasing percentages were 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD and 3,3',4,4',5-PCB (#126), and they accounted for more than 60% of the total WHO-TEQs. PCDFs concentrations and total WHO-TEQs were negatively associated with parity (p<0.05), and maternal age was positively associated with total WHO-TEQs (p<0.01). However, the associations with body mass index (BMI) and fish intake during pregnancy were not significant. These results were suggested that parity and maternal age are an important factor affecting the concentrations of PCDD/DFs and dl-PCBs in these specimens.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.1
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• pp.19-26
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• 2017

Surface air temperature ($T_{air}$) is a key variable for the meteorology and climatology, and is a fundamental factor of the terrestrial ecosystem functions. Satellite remote sensing from the Moderate Resolution Imaging Spectroradiometer (MODIS) provides an opportunity to monitor the $T_{air}$. However, the several problems such as frequent cloud cover and mountainous region can result in substantial retrieval error and signal loss in MODIS $T_{air}$. In this study, satellite-based $T_{air}$ was estimated under both clear and cloudy sky conditions in Gangwon Province using Aqua MODIS07 temperature profile product (MYD07_L2) and GCOM-W1 Advanced Microwave Scanning Radiometer 2 (AMSR2) brightness temperature ($T_b$) at 37 GHz frequency, and was compared with the measurements from the Automated Mountain Meteorology Stations (AMOS). The application of ambient temperature lapse rate was performed to improve the retrieval accuracy in mountainous region, which showed the improvement of estimation accuracy approximately 4% of RMSE. A simple pixel-wise regression method combining synergetic information from MYD07_L2 $T_{air}$ and AMSR2 $T_b$ was applied to estimate surface $T_{air}$ for all sky conditions. The $T_{air}$ retrievals showed favorable agreement in comparison with AMOS data (r=0.80, RMSE=7.9K), though the underestimation was appeared in winter season. Substantial $T_{air}$ retrievals were estimated 61.4% (n=2,657) for cloudy sky conditions. The results presented in this study indicate that the satellite remote sensing can produce the surface $T_{air}$ at the complex mountainous region for all sky conditions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.44-54
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• 2001

This study was conducted to estimate microclimate of natural deciduous forest in national forest of Pyungchang, Kangwon province and to investigate the effects of the microclimatic conditions on the periodic annual increment of diameter by site types. In this study, site was first classified by nine types considering both elevation (higher than 1,000 m, 700∼1,000 m, and lower than 700 m) and topographical conditions (ridge, slope and valley). For each of site types, diameter growth was measured by using increment borer and periodic annual increment of diameter was then analyzed. A topoclimatological technique, for estimating microclimatic conditions, which make use of empirical relationships between the topographical factor and the climatic normals in the study area was applied to produce monthly mean, maximum and minimum temperatures, relative humidity, precipitation and hours of sunshine. From these monthly estimtes, 17 weather variables such as warmth index, coldness index, index of aridity etc. which affect the diameter growth were computed for each of site types. The periodic annual increment of diameter was then correlated with and regressed on the 17 weather variables to examine effects of microclimatic conditions on the diameter growth by site types. From the correlation analysis, it was found that the diameter growth by site types was positively correlated with all of 17 weather variables except the warmth index. Especially, the conditions such as high relative humidity and large amount of sunshine hours provide favorable environment for the growth of diameter. On the other hand, it was also found that diameter growth was negatively iufluenced by warmth index. According to the regression analysis, the periodic annual increment of diameter could be well predicted by index of aridity and mean relative humidity for the growing season.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.93-100
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• 2010

Trip generation is the first step in the conventional four-step model and has great effects on overall demand forecasting, so accuracy really matters at this stage. A linear regression model is widely used as a current trip generation model for such plans as urban transportation and SOC facilities, assuming that the relationship between each socio-economic index and trip generation stays linear. But when rapid urban development or an urban planning structure has changed, socio-economic index data for trip estimation may be lacking to bring many errors in estimated trip. Hence, instead of assuming that a socio-economic index widely used for a general purpose, this study aims to develop a new trip generation model by type based on the market separation for the variables to reflect the characteristics of various zones. The study considered the various characteristics (land use, socio-economic) of zones to enhance the forecasting accuracy of a trip generation model, the first-step in forecasting transportation demands. For a market separation methodology to improve forecasting accuracy, data mining (CART) on the basis of trip generation was used along with a regression analysis. Findings of the study indicated as follows : First, the analysis of zone characteristics using the CART analysis showed that trip production was under the influence of socio-economic factors (men-women relative proportion, age group (22 to 29)), while trip attraction was affected by land use factors (the relative proportion of business facilities) and the socio-economic factor (the relative proportion of third industry workers). Second, model development by type showed as a result that trip generation coefficients revealed 0.977 to 0.987 (trip/person) for "production" 0.692 to 3.256 (trip/person) for "attraction", which brought the necessity for type classifications. Third, a measured verification was conducted, where "production" and "attraction" showed a higher suitability than the existing model. The trip generation model by type developed in this study, therefore, turned out to be superior to the existing one.

• Korean Security Journal
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• no.42
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• pp.59-85
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• 2015

The purpose of this study is to establish the structural relationship among organizational ethical climate, job satisfaction, and organizational citizenship behavior. It was intended for the private security guards who work in the security companies in Seoul and Gyeonggi from Jan. 1st, 2014 to Apr. 1st, 2014 to achieve the purpose like this. Purposive sampling was used as the sampling method according to this and sampling of 400 persons was done. However, the samples of 372 persons were finally used in the analysis through the process to check faithless answers, double answers, and abnormal data. The collected data was analyzed according to the purpose of the study by utilizing STATA 13.0 and AMOS 17.0. And for statistic techniques, frequency analysis, descriptive analysis, multivariate normality, confirmatory factor analysis(CFA), Pearson's correlation analysis, and structural equation model analysis were carried out. The conclusion gotten from this study through the data analyses according to the methods and procedure like this is as follow: First, organizational ethical climate has found to have the positive effect on job satisfaction(Non-standard $B=1.427^{***}$). That is, it can be interpreted that organizational ethical climate positively affects superiors, fellow employees, pay, current duties, and chances of promotion. Second, job satisfaction has found not to have the significant effect on organizational citizenship behavior. That is, it can be interpreted that job satisfaction does not affect altruism, conscience, and participation behavior. Third, organizational ethical climate has found to have the positive effect on organizational citizenship behavior (Non-standard $B=.361^{***}$). That is, it can be interpreted that organizational ethical climate positively affects altruism, conscience, and participation behavior. Fourth, the relationship between organizational ethical climate and organizational citizens has found that there is no any indirect effect in the bootstrapping estimation result to establish the indirect effect of job satisfaction. Fifth, the relationship between organizational ethical climate and job satisfaction has found that there are the moderating effects in the analytical result of the moderating effects of person-organization fit. That is, the effects of organizational ethical climate on job satisfaction have found that the groups with higher person-organization fit are more positive than those with lower person-organization fit. Sixth, the relationship between job satisfaction and organizational citizenship behavior has found that there are moderating effects in the analytical result of person-organization fit. That is, the effects of job satisfaction on organizational citizenship behavior have found that the groups with higher person-organization fit are more positive than those with lower person-organization fit.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.105-112
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• 2001

This study was carried out to analyze the genetic variation and to estimate both heritabilities and genetic gains for height and diameter growth of 20-year-old open-pollinated progenies of Korean white pine in three different sites. For there, analysis of variance for both height and diameter growth was conducted to see if there exist significant differences among families, sites, blocks, and their interactions exist or not and to analyze the variance components for each factor. Mean height and diameter at Gapyeong site were 7.65m and 11.92cm, respectively. they were 7.42m and 11.35cm at Gwangiu site, 6.13m and 8.41cm at Youngdong site, and 7.12m and 10.68cm for the overall sites. The family No. 20 showed the most excellent growth of 7.99m in mean height and 12.14cm in mean diameter for all sites surveyed. The estimates of heritabilities for individual-tree and family were, 0.35~0.73 and 0.65~0.83 for height growth, and 0.12~0.40 and 0.46~0.75 for diameter growth, respectively. For the combined data from all the sites, the estimates of individual tree heritability were 0.60 for height and 0.20 for diameter, and those of family were 0.91 for height and 0.77 for diameter. Heritability estimates varied with testing sites, and those for height were higher than those for diameter in all sites. Given equal intensity of selection, combined selection method provided the most efficient genetic gains for both height and diameter growth.