• Tunnel and Underground Space
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• v.9 no.1
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• pp.20-26
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• 1999

The completion of the Bakun Diversion Tunnel is subsequently to the Main Dam construction. Therefore, the completion date is very important for the Bakun Hydroelectric Project. Generally, the tunnel lining work as a finishing phase of the tunnelling project occupies a important portion as well as an excavation and a support work of the tunnels in respect to the construction cost and period. Internal section of Bakun Diversion Tunnel is designed circular shape to reduce the roughness of the water flow with 12 meters in diameter of total length 4314.6 meters of 3 tunnels. The lining thickness is varied between 500 mm and 700 mm depending on the structural condition. From the original Tender design of the Bakun tunnels, the required quantity of steel bars was 5,985 ton designed by Reinforced Concrete (RC) through the entire tunnel linings. During the detail design stage by the consideration of the rock conditions and various load conditions, we could suggest five kinds of RC lining type including plain concrete lining type. Through the detail design modification, we could reduce the required amount of steel bars to 2,178 ton, as a half of original Bill of Quantity. Finally, this design modification give us the time and cost saving effect to catch up the construction progress in time.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.106-110
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• 2001

In an effort to evaluate the economic value and durability of the expanded rice hull as substrates, changes in the physical and chemical properties of material and plant growth in that substrate were studied. Using and electron microscope, the structure of used and new expanded rice hull substrate was examined. Considerable decomposition was found in the substrate which had been used one to three times. Compactness and lowered porosity in the used substrates were probably caused by decomposition. The results of cation analysis showed the possible destruction of cell wall of rice hulls. Abundant $Ca^{2+}$ in the substrates used for two to three times also indicated the possibility of decomposition. In tomato yield comparison, 15.2% more yield of tomato fruit in a new substrates indicated the negative effects of decomposition of one-time used substrates. Yield decreased in the substrates used for three times. if perlite substrates is used for three years before renewal and the cost of the perlite renewal is counted. 65.3% saving in the cost will be realized with the use of an expanded rice hull substrate. Another positive effect of the expanded rice hull substrate is the decrease of environmental contamination.n.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1275-1280
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• 2009

In recent bridge design, studies on application of external prestress have actively been conducted. When prestress is applied to steel structures, the limit value of elastic strain with large load increases with reduction of steels, this method is economic in cost. According to study by Brodka (1969), steel plate bridges with prestress has an effect on cost saving of about 15% compared with structures without prestress. For that reason, our country recently adopted this method in construction of temporary bridges and various engineering technologies have been developed which made stress correction, droop correction and long-span construction possible with relatively small cross sections. This study verifies the method of application of prestress in temporary steel structures, the influence of high-strength tendon arrangement and the effects of composite structures of steel plates and high-strength tendons based on existing method.

• Plant Journal
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• v.8 no.3
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• pp.55-63
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• 2012

This study aims to suggest the improved business process by analyzing the current design process on work flow of the 3D design of power plant, drawing a problems and setting the improving direction through the integration method of the business process reengineering(BPR). In order to realize the improved business process, the integrated design performance system focused on the 3D design was established and accordingly the study analyzed cases of project performances through the integration system and drew the improved effects quantitatively. In the result of the project performance applied with the 3D design integration system, it showed 20.4% design cost saving effect for appropriate rated cost and the integration of design information from each design parts, sub contracters and vendors reduced overlapped works and improved the consistency of repeated design alteration.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3B
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• pp.207-215
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• 2006

It has known that the handover based on MIP in mobile environments has many constraints for proving seamless service due to well hon problems. Although there has been researching for the solutions, such as MRSVP and HMRSVP etc, it is difficult to do the research related with QoS due to the issues based on MIP used as a seamless mobility. In this paper, the seamless provides in a mobility based on SCTP, which is applied by IntServ for end-to-end QoS service. The paper also proposes the path management scheme for saving reservation cost. the scheme searches a new path on the moving mobile terminal and reserves the resources on the path for providing seamless QoS service. The paper is also analyzed on the comparition between a SCTP based and MIP based solutions. the scheme is evaluated using the cost effect saved for resource reservation.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.29-33
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• 2006

To develop environmentally friendly bio-materials for animal feed, the potential of using mushroom was studied. Adding Flammulina velutipes cultivation media wastes (FCMW) has shown beneficial effects on broiler meat quality and production cost because of the $10{\sim}20%$ saving in feeds for broiler chicken. However, differences proximate composition between FCMW and commercial broiler chicken feed were observed. FCMW had higher contents of crude fat (6.2%) and crude fiber (13.7%) than the commercial broiler feed which had crude fat and crude fiber of 4.0%, and 6.0%, respectively. But FCMW crude protein contents were lower (12.2%) than those in commercial broiler (19.0%). Adding $5{\sim}10%$ of FCMW to broiler chicken feed increased amino acid concentration upto $33{\sim}38%$ in the meat, but adding more than 20% decreased amino acid concentration.

• Advances in environmental research
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• v.10 no.1
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• pp.17-41
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• 2021

Kazakhstan's cities experience high concentrations levels of atmospheric particulate matter (PM), which is well-known for its highly detrimental effect on the human health. A further increase in PM concentrations in the future could lead to a higher air pollution-caused morbidity and mortality, causing an increase in healthcare expenditures by the government. However, to prevent elevated PM concentrations in the future, more stringent standards could be implemented by lowering current maximum allowable PM concentration limit to Organization for Economic Co-operation and Development (OECD)'s limits. Therefore, this study aims to find out what impact this change in environmental policy towards PM has on state economy in the long run. Future PM10 and PM2.5 concentrations were estimated using multiple linear regression based on gross regional product (GRP) and population growth parameters. Dose-response model was based on World Health Organization's approach for the identification of mortality, morbidity and healthcare costs due to air pollution. Analysis of concentrations revealed that only 6 out of 21 cities of Kazakhstan did not exceed the EU limit on PM10 concentration. Changing environmental standards resulted in the 71.7% decrease in mortality and 77% decrease in morbidity cases in all cities compared to the case without changes in environmental policy. Moreover, the cost of morbidity and mortality associated with air pollution decreased by $669 million in 2030 and $2183 million in 2050 in case of implementation of OECD standards. Thus, changing environmental regulations will be beneficial in terms of both of mortality reduction and state budget saving.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.251-259
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• 2023

In this study, as a foundational research aimed at promoting the efficient recycling and environmentally friendly disposal of construction waste through the activation of a selective dismantling system, our primary objective was to analyze the economic feasibility of implementing selective dismantling. To achieve this, we conducted an assessment on a 5-story residential building with a construction area of 2,400 m² as a case study. When considering the additional cost of dismantling construction ① the reduction in waste disposal costs due to decreased mixed waste, ② and the potential revenue from recycling through the separation and sorting of waste materials, and ③ we were able to comprehensively confirm that there is an expected cost-saving effect totaling 34,727,000 KRW when compared to conventional demolition methods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.2
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• pp.73-80
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• 2003

An experiment was carried out at the Field Laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh from March to July, 2001 to investigate the effect of biofertilizers on morpho-physiological characters of okra. The experiment was laid out in a randomized complete block design with four replications. There were nine treatments such as $\textrm{T}_0$ (control), $\textrm{T}_1$ (Azotobacter biofertilizer), $\textrm{T}_2$ (Azospirillum biofertilizer), $\textrm{T}_3$ (Azotobacter+Azospirillum biofertilizers), $\textrm{T}_4$ (Azotobacter+Cowdung 5 ton $\textrm{ha}^{-1}$), $\textrm{T}_5$ (Azospirillum+Cowdung 5 ton $\textrm{ha}^{-1}$), $\textrm{T}_6$(Azotobacter+Azospirillum+Cowdung 5 ton $\textrm{ha}^{-1}$), $\textrm{T}_7$ (Cowdung 5 ton $\textrm{ha}^{-1}$) and $\textrm{T}_8$ (60% Nitrogen). The experimental results revealed that significant variations exist among the treatments regarding morphological characters e.g. plant height, number of leaves/plant, stem base diameter, tap root length, and physiological characters like, root dry weight, leaf area index and crop growth rate. Number of leaves/plant, stem base diameter, root length, root dry weight, leaf area index and crop growth rate were found higher in $\textrm{T}_4$, $\textrm{T}_5$, $\textrm{T}_6$ and $\textrm{T}_8$ than the others. In all the parameters, $\textrm{T}_8$ gave the similar result with biofertilizers in combination with cowdung treatments and $\textrm{T}_7$ showed identical with $\textrm{T}_0$ (control). Biofertilizer treatments had insignificant effect on 1000-seed weight(g). Experimental results mentioned above revealed that morpho-physioligical characters of okra could be modified by the application of biofertilizer+cowdung. However, biofertilizers+Cowdung treatments were comparable to $\textrm{T}_8$(60% Nitrogen) in this study. This suggests that $\textrm{T}_4$ or $\textrm{T}_6$ or $\textrm{T}_5$ were more benificial in environmentally friendly okra cultivation and may be used as an alternative of inorganic nitrogen by saving cost of production and sustaining productivity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.723-728
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• 2014

Hydraulic experiments are performed in order to verify the swash effect of seashore structures installed to prevent scouring. However, a great deal of investment and time are required for producing the test apparatus and seashore structure used to perform the hydraulic experiment. The swash effect can be predicted, however, by using a numerical model and validation can be done based on comparisons of the numerical model and hydraulic experiment analysis results, thereby saving the cost and time required for producing the test apparatus and seashore structure. Taking a polyhedral rubble mound structure as the subject, this study performed a comparative analysis of wave run-up and run-down height of the numerical model interpretative results and the hydraulic experiment results, and validated the interpretative simulation wave test modeling technique. The study also predicted the swash effect by using the numerical interpretation approach method, whereby the volume ratio and friction area of the rubble mound were varied for different results.