• International Journal of Aeronautical and Space Sciences
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• v.7 no.2
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• pp.86-103
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• 2006

Using a combination of force transducer measurement to quantify net lift force, high frame rate camera to quantify and subtract inertial contributions, and Digital Particle Image Velocimetry (DPIV) to calculate aerodynamic contributions in the spanwise plane, the contribution of spanwise flow to the generation of lift force in wings undergoing a pure flapping motion in hover is shown as a function of flapping angle throughout the flapping cycle. These experiments were repeated at various flapping frequencies and for various wing planform sizes for flat plate and span wise cambered wings. Despite the previous identification of the importance of span wise fluid structures in the generation of lift force in flapping wings throughout the existing body of literature, the direct contribution of spanwise flow to lift force generated has not previously been quantified. Therefore, in the same manner as commonly applied to investigate the chordwise lift distribution across an airfoil in flapping wings, spanwise flow due to bulk flow and rotational fluid dynamic mechanisms will be investigated to validate the existence of a direct component of the lift force originating from the flapping motion in the spanwise plane instead.

• Journal of the Korean Society of Marine Environment & Safety
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• v.5 no.1
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• pp.79-93
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• 1999

By the IMF condition, tax revenues of local governments are decreasing, under these conditions, container tax take important proportion in financial resources in Pusan Metropolitan City. However the container tax have time limit until 2001, that is, purposeful tax. But after the creating container tax, the level of accomplishment is very insufficient. So for the activation of local economy, we need active study on the existence problem of container tax. Though the abolition of container tax item is frequently discussed in central government, If the worst case comes, namely the abrogation, it gives big damages to the financial management of Pusan Metropolitan City. Therefore the container tax should be existent for both residents and local government. Because the expansion rate of container tax is so rapid, it makes very critical contribution to the stability and sound condition of Pusan Metropolitan City's finances.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.150-156
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• 2000

In this paper, the human error contributions to the system unavailability are calculated and compared to the mechanical failure contributions. The system unavailability is a probability that a system is in the failed state at time t, given that it was the normal state at time zero. It is a function of human errors committed during maintenance and tests, component failure rates, surveillance test intervals, and allowed outage time. The THERP (Technique for Human Error Rate Prediction), generally called "HRA handbook", is used here for evaluating human error rates. This method treats the operator as one of the system components, and human reliability is assessed in the same manner as that of components. Based on the calculation results, the human error contribution to the system unavailability is shown to be more important than the mechanical failure contribution in the example system. It is also demonstrated that this method is very flexible in that it can be applied to any hazardous facilities, such as gas valve stations and chemical process plants.ss plants.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.125-137
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• 2019

The purpose of this paper is to study the source term behavior after severe accidents by using a semi-kinetic model for simulation and calculation of in-containment activity. The reactor containment specification and the safety features of the containment under different accident conditions play a great role in evaluating the in-containment activity. Assuming in-vessel and instantaneous release of radioactivity into the containment, the behavior of in-containment isotopic activity is studied for noble gasses (Kr and Xe) and the more volatile elements of iodine, cesium, and aerosols such as Te, Rb and Sr as illustrative examples of source term release under LOCA conditions. The results of the activity removal mechanisms indicates that the impact of volumetric leakage rate for noble gasses is important during the accident, while the influence of deposition on the containment surfaces for cesium, mainly iodine isotopes and aerosol has the largest contribution in removal of activity during evolution of the accident.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.219-224
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• 2021

Ion flotation is an efficient method to remove metal ions from aqueous solution. In this work, ion flotation was applied to calcium removal from aqueous solution. The parameters used included sodium stearate (SS) and sodium dodecyl sulfate (SDS) as collectors, 1-butanol and 1-propanol as frothers, pH, and air-flow rate. An L16 orthogonal array was chosen according to the mentioned factors and levels, and experimental tests were conducted according to the Taguchi orthogonal array. The results showed that all of the factors except one had significant effect on the flotation performance. The percentage contribution of parameters showed that type of frother and type of collector made the greatest (43.14%) and the lowest (9.86%) contribution, respectively. In optimal conditions, the recovery of Ca (II) ion was 45.67%. Also, the results illustrated that the Taguchi method could predict calcium removal from aqueous solution by ion flotation with 2.63%. This study showed that the use of ion flotation was an effective method for Ca (II) ion removal from aqueous solution.

• Journal of Korea Port Economic Association
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• v.36 no.3
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• pp.137-154
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• 2020

In this study, we analyze the performance of five major port distriparks and present a development plan. The analysis groups the performance into three categories: revitalization of companies in port distriparks, contribution to the port volume, and contribution to the national economy. The key parameters examined in detail include the ratio of hinterland volume to port volume (container and total cargo), port volume growth contribution rate, and job creation. Our results indicate that Gwangyang and Ulsan Ports showed steady growth for all the indicators analyzed, while Gwangyang Port was the only one among the five ports to display consistent steady growth. The results suggest that to achieve consistent growth, high value-added and specialized port distriparks based on the local economy should be established.

• Health Policy and Management
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• v.8 no.2
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• pp.110-124
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• 1998

Determining of Strategic Business Units in the organization is a major critical process for improving the organizational performance. On increasing the demands for extension in function of health center, many health centers are trying to provide the various services. But most health center determined the kind and level of service without scientific considerations. The purposes of this study are to develope the model for determination of strategic business units in health center and to test the availability of implementation for it. Our model is rooted from the McKinsey matrix analysis of Product Portfolio Analysis which used widely in marketing field. We modified the evaluation criteria of the McKinsey matrix analysis for health care field appropriately. Our evaluation criteria are categorized into two concepts; contribution of service, availability of service. At first, in terms of contribution of service, market size, market growth rate, needs and demands of regional people, existences of alternative services in that region, correspondence with health policy. The other component, availability of service are included the availability of manpower, financial availability, the level of knowhow on service, acceptance of health care manpower. In the result of analysis, we could conclude that antismoking and antialcoholics education programs, health screening program are important strategically in that aspects of contributions and availability of services. Also, vaccination program is important in that aspect of service availability and diet and exercise program, health library are meaningful in the aspect of service contribution. Therefore, we think that efforts to investigate the evaluation criteria for priority setting or determination of service area in health center are useful challenges.

• Journal of Drive and Control
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• v.13 no.2
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• pp.19-25
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• 2016

Recently, drivers have begun to regard comfort in the cabin as one of the most important factors in construction equipment like forklifts. Accordingly, it has become more important to design a forklift cabin with a better sound quality as well as lower sound level, which can make a driver more comfortable. In this paper, the correlation between subjective evaluation and Zwicker's sound quality index was analyzed through a blind test by a few workers in forklifts and other construction equipment in several countries. Correlation analysis showed that Loudness and Sharpness were ranked in sequence, and tendencies were different from country to country. Also, contribution analysis for Loudness and Sharpness using operational transfer path analysis (OTPA), which is widely used in the field of noise, vibration, and harshness (NVH), was performed. However, Loudness and Sharpness cannot be used with OTPA directly because there are no linear relationships between the sources and receivers. In this paper, both are calculated by applying the DIN 45631 method with a contribution rate (%) of 1/3 Octave Sound Pressure Level by OTPA method in addition to considering spectral masking.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.363-377
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• 2016

This study was investigated the pollutant load, contamination properties, pollution condition of the fine parts of tributary, the influence of Nakdong river watershed and etc. in the tributaries. The contaminated tributaries were that among the Kumho and Nam river or were too far from site of water quality monitoring stations, regularly. As a result, the water quality level was almost similar between Nam and Kumho River, except for certain parameter including TN(Total Nitrogen), Chl-a(Chlorophyll-a) and SS(Suspended Solid) in which Kumho river were 20~120%. The point discharge load(kg/day) and load density ($kg/day/km^2$) of tributaries were different the pollution level according to the flow-rate ($m^3/sec$) and stream influence area($km^2$), and the difference of these was observed highly at Nam river. Specific contamination investigation of tributaries in Nam and Kumho river watershed was conducted from two to nine points of the fine parts of tributaries depending on the confluence sites and shapes. This result observed high at the Dalseocheon and Uriyeongcheon, respectively. Beside, the pollutant load contribution rate of Nakdong watershed was high about 10% at the Dalseocheon and Uiryeongcheon. This was due to the differences of the environments about the industrial complex, metropolis residence property, agricultural cultivation, livestock pen and the downstream of non-point source.

• East Asian Economic Review
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• v.16 no.3
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• pp.273-290
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• 2012

While the issue of RMB (Renminbi, Chinese Yuan) revaluation became the focus of world attention in 2003, the reform of the RMB exchange rate regime in 2005 didn't fundamentally solve the RMB appreciation problem, and even in 2008 the global financial crisis made RMB appreciation face new challenges and risks. It appears that the rise in RMB value is caused by supply exceeding demand in China's foreign exchange market; however, intrinsically it is due to the asymmetry in RMB exchange rate formation mechanism. The export tax rebates policy implemented by Chinese government is one of the leading causes of the asymmetry. This study constructs a transmission model between export tax rebates and foreign exchange rates, and applies the Granger Test to validate the causality between kernel variables based on correlative data from 1994-2011, and uses the error correction method to analyze the quantified relations of kernel variables, and finally gets the contribution rate of export tax rebates to RMB appreciation.