• Environmental Engineering Research
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• v.19 no.3
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• pp.269-274
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• 2014

On-site sanitation systems are typically installed to treat grey and toilet wastewaters in areas without sewer and centralized treatment systems. It is well known that, due to inappropriate design and operation, treatment performance of these systems in developing countries is not satisfactory in the removal of pathogens and organic matters. This research aimed to investigate the hydraulic conditions occurring in some on-site sanitation systems and the effects of hydraulic retention times (HRTs) on the system performance. The experiments were conducted with a laboratory-scale septic tank (40L in size) and an actual septic tank (600L in size), to test the hydraulic conditions by using tracer study with HRTs varying at 12, 24 and 48 hr. The experimental results showed the dispersion numbers to be in the range of 0.017-0.320 and the short-circuit ratios in the range of 0.014-0.031, indicating the reactors having a high level of sort-circuiting and approaching complete-mix conditions. The removal efficiency of $BOD_5$ was found to be 67% and the $k_{30}$ values for $BOD_5$ was $2.04day^{-1}$. A modified complete-mix model based on the relationship between $BOD_5$ removal efficiencies and HRTs was developed and validated with actual-scale septic tank data having a correlation coefficient ($R^2$) of 0.90. Therefore, to better protect our environment and minimizing health risks, new generation toilets should be developed that could minimize short-circuiting and improving treatment performance.

• Journal of Korean Society of Rural Planning
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• v.18 no.3
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• pp.25-41
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• 2012

The purpose of this study is to quantitatively analyze the social welfare value given to the designated rural settlement zone by the resident-participated site unit plan that the City of Cheongju is newly attempting to draft. Firstly, the costs and benefits from the site unit planning were estimated. Secondly, through literature review especially focussed on the benefit and cost estimation, on-site questionnaire was designed, and then sample residents of the qualifying sites were asked about their willingness to pay, which could make it possible to estimate the monetary value of its benefits by the contingent valuation method (CVM). Finally, the present value of net benefits (PVNB) was estimated through the derived costs and benefits. As a result of analysis, firstly, the present value of net benefits (PVNB) was found to be 7,641 billion won, which indicated that the implementation of district-unit plan would be able to cause sufficient social welfare value for the effected residents. Secondly, in examining the result of individual average amount for willingness to pay through the CVM, the area that benefited the most was found to be the road improvement. Thirdly, as a result of sensitivity analysis, the parameter with the most effects was the discount rate, which suggested that, in carrying out public projects, excessive market interest rates would not be appropriate.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1155-1159
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• 2018

Foot-and-mouth disease (FMD) is an infectious disease affecting pigs. The control of FMD in swine husbandry is very important because its outbreak results in a vast economic loss. FMD vaccination has effectively controlled FMD; however, it results in economic loss associated with the incidence of lesions in the pork meat at the injection site. The objective of this study was to investigate the effects of transdermal needle-free injection (NFI) of the FMD vaccine on the incidence of lesions at the injection site. Pigs (n=493) in the control group were vaccinated with the FMD vaccine using a commercial syringe needle, while 492 pigs in the transdermal NFI group received the FMD vaccine using a needle-free gas-powered jet injector. After the slaughter of the pigs, the incidence of lesions at the injection site of all pigs was checked by plant workers. The result of this study showed that the incidence of lesions in the pork ham from pigs vaccinated with NFI was 14.82% lower than that in control pigs (p<0.01). In addition, lesions generated in the NFI group were found just in the subcutaneous tissue. Therefore, the incidence of lesions at the injection site in pork from pigs vaccinated with the FMD vaccine can be effectively reduced by using transdermal NFI rather than a conventional syringe needle.

• Natural Product Sciences
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• v.25 no.1
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• pp.28-33
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• 2019

A popular approach for the study of estrogen receptor ${\alpha}$ inhibition is to investigate the protein-protein interaction between the estrogen receptor (ER) and the coactivator surface. In our study, we investigated phytochemicals from Rubus coreanus that were able to disrupt $ER{\alpha}$ and coactivator interaction with an $ER{\alpha}$ antagonist. The E-screen assay and molecular docking analysis were performed to evaluate the effects of the estrogenic activity of R. coreanus extract and its constituents on the MCF-7 human breast cancer cell line. At $100{\mu}g/mL$, R. coreanus extract significantly stimulated cell proliferation ($574.57{\pm}8.56%$). Sanguiin H6, which was isolated from R. coreanus, demonstrated the strongest affinity for the $ER{\alpha}$ coactivator-binding site in molecular docking analysis, with a binding energy of -250.149. The initial results of the study indicated that sanguiin H6 contributed to the estrogenic activity of R. coreanus through the activation of the $ER{\alpha}$ coactivator-binding site.

• Journal of Ecology and Environment
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• v.46 no.3
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• pp.204-217
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• 2022

Background: Increasing land demands for food production have led to biodiversity loss and land degradation in the Madhupur Sal forest. Reforestation activities such as agroforestry and woodlot plantation support the conservation of diversity, restoration of forest and prevention of soil erosion in degraded natural Sal forest. Knowing about these reforestation activities, this study is needed to compare the species composition, richness, and soil nutrients of these two plantation activities to the natural Sal forest in the degraded Madhupur Sal forest in Bangladesh. Results: The analysis showed that in between the reforestation activities, the highest Shannon-Wiener index (1.79), evenness (0.60) and Simpson's index (0.79) were found in the agroforestry site compared to the woodlot plantation site. On the contrary, the highest species richness (n = 14), tree basal area (19.56 m² ha^-1), Margalef's index (1.96) were recorded in woodlot plantation than in the agroforestry site. We observed that at 0-15 cm depth, soil organic matter (2.39%), total nitrogen (0.14%), available phosphorous (62.67 ㎍ g^-1) and exchangeable potassium (0.36 meq/100 g) in agroforestry plots were significantly higher compared to other forest sites. At topsoil (15-30 cm depth), soil organic matter (1.67%) and available phosphorous (21.09 ㎍ g^-1) were found to be higher in agroforestry site. Conclusions: Both reforestation approaches improved soil function, although woodlot plantation had the higher species richness. Therefore, plantation activities by the sustainable implementation of these two practices are the best alternative to restore the biodiversity, richness and conserve soil fertility in the Madhupur Sal forest of Bangladesh.

• Journal of the Korean Society of Safety
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• v.37 no.3
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• pp.24-33
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• 2022

Construction site fatalities accounted for 51.9% of the total fatalities recorded in 2020. It is known that the safety leadership of site managers is important in reducing occupational accidents at construction sites. According to previous domestic and foreign studies, the safety leadership role of managers has significant effects on the safety behavior and safety culture of workers. Therefore, in this study, we identified the factors affecting organizational trust, which are known to be prerequisites for building a safety culture, and sought ways to enhance organizational trust. In this study, measurement data were collected using a self-report questionnaire. A total of 4,373 copies were distributed to workers and managers of business partners who are highly likely to be exposed to occupational injuries, and 3,873 copies were used as final data for analysis, excluding insincere responses and non-responses. As a result of the study, safety leadership was found to have a positive (+) effect on organizational trust, and communication and motivation moderated the relationship between safety leadership and organizational trust. Therefore, for safety leadership to have a positive effect on organizational trust at construction sites, it is imperative that leadership participation includes communication and motivational efforts.

• Earthquakes and Structures
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• v.25 no.1
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• pp.27-41
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• 2023

This study focused on nonlinear effective stress site response analysis using two coupled constitutive models, that is, the DM model (Dafalias and Manzari 2004), which incorporated a simple plasticity sand model accounting for fabric change effects, and the PMDY03 model (Khosravifar et al. 2018), that is, a 3D model for earthquake-induced liquefaction triggering and postliquefaction response. A detailed parametric study was conducted to validate the effectiveness of nonlinear site response analysis and porewater pressure (PWP) generation through a true coupled formulation for assessing the initiation of liquefaction at ground level. The coupled models demonstrated accurate prediction of liquefaction triggering, which was in line with established empirical liquefaction triggering relations in published databases. Several limitations were identified in the evaluation of liquefaction using the cyclic stress method, despite its widespread implementation for calculating liquefaction triggering. Variations in shear stiffness, represented by changes in shear wave velocity (Vs1), exerted the most significant influence on site response. The study further indicated that substantial differences in response spectra between nonlinear total stress and nonlinear effective stress analyses primarily occurred when liquefaction was triggered or on the verge of being triggered, as shown by excess PWP ratios approaching unity. These differences diminished when liquefaction occurred towards the later stages of intense shaking. The soil response was predominantly influenced by the higher stiffness values present prior to liquefaction. A key contribution of this study was to validate the criteria used to assess the triggering of level-ground liquefaction using true coupled effective-stress constitutive models, while also confirming the reliability of numerical approximations including the PDMY03 and DM models. These models effectively captured the principal characteristics of liquefaction observed in field tests and laboratory experiments.

• International Area Studies Review
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• v.15 no.1
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• pp.571-583
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• 2011

We use the properties of competitive location equilibrium to study the relationship between the demand for education and the choice of primary residential location. Consumers can work and live in a comparatively high wage place where there are few education opportunities, or live in a place where education is available and commute to work. If education and employment are each location-specific, there are pooling equilibria in which consumers locate according to their preference for education. In general, the stronger the taste for education, the greater the attraction of living close to the education site and the lower the demand for other goods, including housing. Exploring the effects of the model parameters on the spatial distribution of consumers, we find that a higher frequency of trips taken to the education site, a shorter distance between the work place and the education site, or a greater out-of-pocket education cost each leads to a wider range of consumer types selecting to reside at the education location. We also find that a higher wage lowers the range of consumers who select to live near the education site.

• Korean Journal of Veterinary Service
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• v.40 no.3
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• pp.177-185
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• 2017

In this study, we evaluated the efficacy of a commercial vaccine stress-relieving agent (Anti VS-2 injection) to reduce the adverse effects of foot-and-mouth disease (FMD) vaccination site in 120 pigs on two tested pig farms. The results showed that incidence of pig with abnormal meat, size of abnormal meat and weight of discarded abnormal meat are significantly decreased in Anti VS-2 injection-supplemented FMD vaccinated pig groups (n=60) compared to the non-supplemented FMD vaccinated pig groups (n=60) (P<0.05). And the average economic loss by discard of abnormal meat were estimated 99,382 won or 21,514 won in the non-supplemented FMD vaccinated groups or in the Anti VS-2 injection-supplemented FMD vaccinated groups, respectively, showing that the cost saving effect was 78% (77,869 won). In conclusion, it is expected to reduce the incidence and severity of abnormal meat in the FMD vaccinated pigs and to contribute not only to the reduced economic loss of pig farmers but also to the promotion of food hygiene when the Anti VS-2 injection is mixed with FMD vaccine.

• Journal of Home Health Care Nursing
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• v.16 no.2
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• pp.98-107
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• 2009

Purpose: The objective of this study was to identify the effects of a telephone follow-up program on patient compliance, urea kinetic modeling and incidence of infection in patients with continuous ambulatory peritoneal dialysis (CAPD). Method: A pretest-posttest design with a nonequivalent control group was used to examine the effects of a telephone follow-up program for 12 weeks in a group of 39 CAPD patients. The telephone follow-up group of 17 patients received telephone follow-up 10 min once a week for 1 month and 10 min twice a month for 2 months during 12 weeks compared to control group of 22 who patients received usual care. Results: The telephone follow-up group showed no significant changes in patient compliance and urea kinetic modeling, although patients with CAPD receiving a telephone follow-up showed reduced incidence of exit site infection during the intervention compared with the control group. Conclusion: Telephone follow-up program for CAPD patients may decrease the incidence of exit site infection. Future studies with a larger sample be done utilizing diet and exercise reinforcement program combined with telephone follow-up as a nursing intervention for patients with CAPD.