• Korean Journal of Organic Agriculture
• /
• v.23 no.2
• /
• pp.359-372
• /
• 2015

This study was to assess the effects of sowing mixed legume forage and applying fermented cattle manure on the productivity and feed value of whole crop wheat (WCW) as a representative of winter crops and also to estimate feeding capacity of Korean native cattle (Hanwoo) per unit area by defining optimal application levels of cattle manure for more fertile soil and manure recycling for the purpose of reduced environmental pollution and efficient production of organic forage contributable to production of organic animal products. Sowing mixed legume forage significantly (p<0.05) increased yields of dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) for WCW compared to WCW alone sowing, but there were no differences between mixed sowing treatments. The yields of DM, CP and TDN were significantly (p<0.05) higher in 100~150 kg N/ha. The CP and acid detergent fiber (ADF) contents were highest in mixed sowing with hairy vetch, followed by sowing mixed forage pea and WCW alone (p<0.05). There were no differences in CP among cattle manure application levels. As nitrogen application level increased, ADF content increased (p<0.05), but TDN content decreased (p<0.05). Feeding capacity of organic Hanwoo (head/ha) weighing 450 kg of body weight with 400 g of daily gain significantly (p<0.05) increased due to mixed sowing with legume forage, and with increasing application levels of fermented cattle manure, feeding capacity significantly (p<0.05) increased. The results indicated that mixed-sowing of WCW and legume forage not only reduced nitrogen application level of fermented cattle manure by over 50 kg per ha but also increased their feed value and productivity, and feeding capacity. This would be contributable to diversity of forage resources as well as production of organic animal product by creating low cost and high quality of forage.

• Korean Journal of Poultry Science
• /
• v.15 no.3
• /
• pp.211-218
• /
• 1988

Data on egg number from time of first lay to 71 week of age were obtained from samples of single comb white leghorn breeder and brown layer breeder populations which were raised at manny breeding Co. These data were used to estimate the heritabilities of age at sexual maturity, early egg number, residual egg number and annual egg number. Also, the genetic correlation coefficients between these traits were estimated and selection efficiencies of each segment in early part record were estimated by use of the heritabilities and generic correlations. The estimated heritabilities and standard errors in two lines(W and B) were $0.30\pm0.07$ and $0.33\pm0.08$ at early records, $0.19\pm0.06$ and $0.18\pm$0.05 at residual records and $0.37\pm0.09$ and $0.49\pm0.10$ at time of first lay. Those at annual records were $0.24\pm0.06$ equally. The estimated correlation coefficients and standard errors between early record and annual record were $0.76\pm0.08$ and $0.77\pm0.07$. Those between early record and residual record were $0.46\pm0.15$ and $0.39\pm0.16$ respectively. At improving annual egg production per year, selection based on early part record(SM to 40 week of age) would be 69% more efficient than on annual record in line W and 80% more efficient than on annual record in line B. But, if it were considered that egg weight decreased due to sexual maturity and cost for data collection, use of selected segment from 35~40week of age in line W and from 31~40 week of age in line B would be desired in spite of a. small loss in relative selection efficiency. The generation interval would not be shortened.

• Environmental and Resource Economics Review
• /
• v.23 no.4
• /
• pp.719-746
• /
• 2014

This study attempts to estimate the value of the water quality improvement by deriving the equilibrium price of the water pollutant emission permit for the imaginary water pollutant emission trading market. It is reasonable to say that there is already an implicit social agreement for the unit value of water pollutant, when the government set the Total Water Pollutant Loading System for the major river basin as a part of the Comprehensive Measures for Water Management, particularly for the Nakdong River Basin. Therefore, we can derive the unit value of water pollutant emission, which is already implied in the pollution allowance for each city or county by the Total Water Pollutant Loading System. Once estimated, it will be useful to the economic assessment of the water quality related projects. An imaginary water pollutant emission trading system for the Nakdong River Basin, where Total Water Pollutant Loading System is already effective, is constructed for the estimation of the equilibrium price of water pollutant permit. By estimating marginal abatement cost curve or each city or county, we can compute the equilibrium price of the permit and then it is regarded as the economic value of the water pollutant. The marginal net benefit function results from the relationship between the emission and the benefit, and then the equilibrium price of permit comes from constructing the excess demand function of the permit by using the total allowable permit of the local government entity. The equilibrium price of the permit would be estimated to be $1,409.3won/kg{\cdot}BOD$. This is within reasonable boundary compared for the permit price compared to foreign example. This permit price would be applied to calculate for the economic value of the water quality pollutants, and also be expected to use directly for the B/C analysis of the business involved with water quality change.

• Journal of Animal Science and Technology
• /
• v.44 no.4
• /
• pp.453-458
• /
• 2002

In order to search for reliable rapid methods of estimating bacterial counts in pork, this study was tried to measure resazurin reduction time which is simple in experimental method, low in analytical cost, able to estimate bacterial count within short time. The results were summarized as follows; Correlation coefficient between initial bacterial log count(25$^{\circ}C$/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 25$^{\circ}C$ and 30$^{\circ}C$ was higher than other conditions as -0.95 and -0.94, respectively. Considering correlation coefficient and reduction time, incubation temperature was compatible at 30$^{\circ}C$, and regression equation(RE) was Y = -0.4386X + 7.7870. At a bacterial load of $10^2$cfu/$cm^2$, $10^3$cfu/$cm^2$ and $10^4$cfu/$cm^2$ in pork, reduction time was 13.2hr, 10.9hr and 8.6hr, respectively. Correlation coefficient between initial bacterial log count(30$^{\circ}C$/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 30$^{\circ}C$ was highest among other conditions as -0.93, and RE was Y = -0.4171X + 7.5540. At a bacterial load of $10^2$cfu/$cm^2$, $10^3cfu/$cm^2$ and $10^4cfu/$cm^2$ in pork, reduction time was 13.3hr, 10.9hr and 8.5hr, respectively. Correlation coefficient between initial bacterial log count(35$^{\circ}C$/72hr, Y) and resazurin reduction time(X) from blue color to pink color during incubation at 30$^{\circ}C$ was highest among other conditions as -0.93, and RE was Y = -0.3514X + 6.7513. At a bacterial load of $10^2$cfu/$cm^2$, $10^3$cfu/$cm^2$ and $10^4$cfu/$cm^2$ in pork, reduction time was 13.5hr, 10.7hr and 7.8hr, respectively.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.11
• /
• pp.947-956
• /
• 2009

Residual petroleum hydrocarbons after an oil spill may accumulate in the marine benthic ecosystem due to their high hydrophobicity. A lot of monitoring data are required for the estimation of ecosystem exposure to residual petrochemicals in an ecological risk assessment in the affected region. To save time and cost, the environmental exposure to them in the affected ecosystem can also be assessed using a simple food-web bioaccumulation model. In this study, we evaluated residual concentrations of four selected polycyclic aromatic hydrocarbons (phenanthrene, anthracene, pyrene, and benzo[a]pyrene) in a hypothetic benthic ecosystem composed of six species under two exposure scenarios. Body-residue concentration ranged 5~250 mg/kg body depending on trophic positions in an extreme scenario in which the aqueous concentrations of PAHs were assumed to be one-tenth of their aqueous solubility. In addition, bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were evaluated for model species. The logarithm of bioconcentration factor (log BCF) linearly increased with increasing the logarithm of 1-octanol-water partition coefficient (log $K_{OW}$) until log $K_{OW}$ of 7.0, followed by a gradual decrease with further increase in log $K_{OW}$ without metabolic degradation. Biomagnification became significant when log $K_{OW}$ of a pollutant exceeded 5.0 in the model ecosystem, indicating that investigation of food-web structure should be critical to predict biomagnifications in the affected ecosystem because log $K_{OW}$ values of many petrochemicals are higher than 5.0. Although further research is required for better site-specific evaluation of exposure, the model simulation can be used to estimate the level of the ecosystem exposure to residual oil contaminants at the screening level.

• Clinical and Experimental Pediatrics
• /
• v.48 no.10
• /
• pp.1082-1089
• /
• 2005

Purpose : Abdominal obesity is encountered as a risk factor for cardiovascular diseases. However, the anthropometric cut-off value to estimate the cardiovascular risk, has not been suggested. This study was designed to find the relationship between the abdominal fat and various parameters of obesity to find the cardiovascular risk factors related to abdominal obesity and to establish practical methods to measure them. Methods : Twenty seven obese Korean adolescents of moderate to severe degree and 22 healthy adolescents were enrolled. The body mass index(BMI), arm circumference and skinfold thickness were measured. Furthermore, blood lipid, sugar, insulin and four different cytokines' levels were checked and the distribution of body composition was measured by bioelectrical impedance analysis. The subcutaneous and intra-abdominal fat thickness by abdominal ultrasonography(US) and the total and intra-abdominal fat area by abdominal computerized tomography(CT) were measured in the obese group. Results : The most accurate method to measure abdominal fat in children is abdominal CT and the fat mass measured by bioelectrical impedance was strongly correlated with it(r=0.954). It was also correlated with arm circumference, fat thickness measured by abdominal US, BMI, aspartate aminotransferase(AST), alanine aminotransferase(ALT) and triglyceride level. Conclusion : Abdominal CT is the most accurate method to measure intra-abdominal fat, and it can be replaced by abdominal US for cost effectiveness. The screening methods that can be used at school or in outpatient basis include bioelectrical impedance, waist/hip ratio, and arm circumference. The cardiovascular risk factors include leptin, triglyceride and insulin level.

• Clinical and Experimental Pediatrics
• /
• v.46 no.4
• /
• pp.326-334
• /
• 2003

Purpose : The objectives of this study were to estimate the prevalence of obesity in adolescents; to study the association between obesity, blood pressure, and dyslipidemia; and to evaluate the superiority of waist circumference to waist/hip ratio(WHR) in central obesity. Methods : We selected 1382 adolescents(M : F=690 : 692) aged from 11 to 18 years(mean age; boys 15.0, girls 15.4) in Incheon. We measured weight, height, waist, waist/hip ratio, and blood pressure, with blood sampling to evaluate the dyslipidemia. Results : The prevalence of obesity was 6.7% in boys and 6.9% in girls by body mass index(BMI). The prevalence of systolic hypertension was 15.7% in normal group, 32.4% in the overweight group, and 35.4% in the obese group by BMI. The prevalence of diastolic hypertension was 4.9% in the normal group, 6.9% in the overweight group, and 14.6% the in obese group. In boys and girls, BMI, waist circumference, and WHR were positively correlated with systolic and diastolic blood pressure. respectively. In boys, triglyceride was positively correlated with waist circumference(r=0.34, P<0.05). In boys and girls, BMI was highly correlated with obesity index(r=0.98, each), with waist circumference(r=0.89, r=0.82, respectively), and with body fat(r=0.85, r=0.89) respectively. Conclusion : These data suggest the importance of the screening of blood pressure in obese adolescents, with prevention and intervention of obesity since it may be the most cost-effective way of reducing the complications related with obesity.

• Journal of Korean Society for Atmospheric Environment
• /
• v.33 no.4
• /
• pp.377-392
• /
• 2017

A set of BFM (Brute Force Method) simulations with the CMAQ (Community Multiscale Air Quality) model were conducted in order to estimate self-contributions and conversion rates of PPM (Primary $PM_{2.5}$), $NO_x$, $SO_2$, $NH_3$, and VOC emissions to $PM_{2.5}$ concentrations over the SMA (Seoul Metropolitan Area). CAPSS (Clean Air Policy Support System) 2013 EI (emissions inventory) from the NIER (National Institute of Environmental Research) was used for the base and sensitivity simulations. SCCs (Source Classification Codes) in the EI were utilized to group the emissions into area, mobile, and point source categories. PPM and $PM_{2.5}$ precursor emissions from each source category were reduced by 50%. In turn, air quality was simulated with CMAQ during January, April, July, and October in 2014 for the BFM runs. In this study, seasonal variations of SMA $PM_{2.5}$ self-sensitivities to PPM, $SO_2$, and $NH_3$ emissions can be observed even when the seasonal emission rates are almost identical. For example, when the mobile PPM emissions from the SMA were 634 TPM (Tons Per Month) and 603 TPM in January and July, self-contributions of the emissions to monthly mean $PM_{2.5}$ were $2.7{\mu}g/m^3$ and $1.3{\mu}g/m^3$ for the months, respectively. Similarly, while $NH_3$ emissions from area sources were 4,169 TPM and 3,951 TPM in January and July, the self-contributions to monthly mean $PM_{2.5}$ for the months were $2.0{\mu}g/m^3$ and $4.4{\mu}g/m^3$, respectively. Meanwhile, emission-to-$PM_{2.5}$ conversion rates of precursors vary among source categories. For instance, the annual mean conversion rates of the SMA mobile, area, and point sources were 19.3, 10.8, and $6.6{\mu}g/m^3/10^6TPY$ for $SO_2$ emissions while those rates for PPM emissions were 268.6, 207.7, and 181.5 (${\mu}g/m^3/10^6TPY$), respectively, over the region. The results demonstrate that SMA $PM_{2.5}$ responses to the same amount of reduction in precursor emissions differ for source categories and in time (e.g. seasons), which is important when the cost-benefit analysis is conducted during air quality improvement planning. On the other hand, annual mean $PM_{2.5}$ sensitivities to the SMA $NO_x$ emissions remains still negative even after a 50% reduction in emission category which implies that more aggressive $NO_x$ reductions are required for the SMA to overcome '$NO_x$ disbenefit' under the base condition.

• Journal of agricultural medicine and community health
• /
• v.24 no.1
• /
• pp.65-77
• /
• 1999

In order to estimate the utilization pattern of a rural health subcenter, and to identify the recognition for it among the farmhouse members in a suburban area, a questionnaire survey was carried out for objects of 696 population. The results observed were as follows: The annual utilization rate of rural health subcenter for a basic health service unit was 25.0 per 100 persons, and annual mean visiting times was 0.22 times. And the most frequent disease by annual health subcenter utilization illness was musculoskeletal disease(30.6%), and the next was respiratory disease(14.1%), gastrointestinal disease(13.9%) by order. Favorite reason for community health subcenter utilization were near distance from living place(49.6%), lower disease severity(18.9%) and lower medical cost(18.1%) by order. But disfavoring reasons for it were absence of specialist(20.2%), non effective treatment(19.2%) and insufficient equipment(14.7%) by order. And insufficient items about community health subcenter utilization were restriction of treatment limit(40.7%), lower reliance(22.5%) and difficulty in traffic(13.4%) by order. The results of logistic regression analysis suggested that statistically significant factors in health subcenter utilization was educational level. The desirable works for the health subcenter in a suburban area were disease control of elderly and disease preventing service. These results suggested that to increase the utilization of rural health subcenter in a suburban area and to promote the accessibility of rural residents to primary health care, there must be considered public relation about health subcenter, improvement of medical quality and change of priority about health subcenter's works.

• Journal of Korean Society of Transportation
• /
• v.35 no.4
• /
• pp.360-373
• /
• 2017

The BTO-a projects is the types, which has a demand risk among the type of PPP projects in Korea. When demand risk is realized, private investor encounters financial difficulties due to lower revenue than its expectation and the government may also have a problem in stable infrastructure operation. In this regards, the government has applied various risk sharing policies in response to demand risk. However, the amount of government's risk sharing is the government's contingent liabilities as a result of demand uncertainty, and it fails to be quantified by the conventional NPV method of expressing in the text of the concession agreement. The purpose of this study is to estimate the value of investment risk sharing by the government considering the demand risk in the profit sharing system (BTO-a) introduced in 2015 as one of the demand risk sharing policy. The investment risk sharing will take the form of options in finance. Private investors have the right to claim subsidies from the government when their revenue declines, while the government has the obligation to pay subsidies under certain conditions. In this study, we have established a methodology for estimating the value of investment risk sharing by using the Black - Scholes option pricing model and examined the appropriateness of the results through case studies. As a result of the analysis, the value of investment risk sharing is estimated to be 12 billion won, which is about 4% of the investment cost of the private investment. In other words, it can be seen that the government will invest 12 billion won in financial support by sharing the investment risk. The option value when assuming the traffic volume risk as a random variable from the case studies is derived as an average of 12.2 billion won and a standard deviation of 3.67 billion won. As a result of the cumulative distribution, the option value of the 90% probability interval will be determined within the range of 6.9 to 18.8 billion won. The method proposed in this study is expected to help government and private investors understand the better risk analysis and economic value of better for investment risk sharing under the uncertainty of future demand.