• Journal of Biosystems Engineering
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• v.20 no.1
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• pp.22-35
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• 1995

Pepper is the most important horticultural plant in Korean farm. Pepper harvesting has been known to be the most difficult process in pepper cultivation so that demand for mechanization is strong. In a research to develop a pepper harvesting machine performance and capacity of the harvester should be determined based on both economical feasibility and machine design concept. In order to accomplish an economical analysis of the pepper harvester, a mathematical model for comparing manual harvesting cost to machine harvest cost was developed. Validity of the model depends on the data used in the model. Economical information for the model variables was acquired from the result of farm survey on pepper cultivation technique and economics of pepper farmer. Technical information on pepper harvester were also collected through literature review and analyzed. Based on the economical analysis and synthesis of the technical information on pepper harvesters, its performance and capacity were determined. The operating performances of the harvester such as cutting, conveying, flipping, pepper removing and post-processing (sorting) were determined. Daisy capacity of the machine was determined to be 0.41 ha. A pepper harvester with the suggested capacity was economically feasible if the price of pepper harvester, pepper recovery ratio and service life of harvester were about 6 million won, 80%, and 4 years, respectively.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.313-320
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• 2017

Price fluctuation contract is imperative and of paramount essence in the construction industry as it provides adequate relief and cushioning for changes in the prices of input resources during construction. As a result, several methods have been devised to better help in arriving at fair recompense in the event of price chang es. However, stakeholders often appear not to be satisfied with the existing methods of fluctuation evaluation, ostensibly because of the challenges associated with them. The aim of this study was to identify the challenges to usage of building construction cost indices in Ghana. Data was gathered from contractors and quantity surveying firms. The study utilized survey questionnaire approach to elicit responses from the contractors and the consultants. Data gathered was analyzed scientifically, using the Relative Importance Index (RII) to rank the problems associated with the existing methods. The findings revealed the following among others; late release of data; inadequate recovery of costs; and work items of interest not included in the published indices as the main challenges of the existing methods. This study will provide useful lessons for policy makers and practitioners in decision making towards the usage and improvement of available indices.

• Advances in environmental research
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• v.5 no.2
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• pp.125-140
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• 2016

The paper is focused on the economic analysis of two hydrometallurgical processes for recovery of yttrium and other rare earth elements (REEs) from fluorescent phosphors of spent lamps. The first process includes leaching with sulphuric acid and precipitation of a mixture of oxalates by oxalic acid, the second one includes leaching with sulphuric acid, solvent extraction with D2EHPA, stripping by acid and recovery of yttrium and traces of other rare earths (REs) by precipitation with oxalic acid. In both cases the REEs were recovered as oxides by calcination of the oxalate salts. The economic analysis was estimated considering the real capacity of the HydroWEEE mobile's plant ($420kg\;batch^{-1}$). For the first flow-sheet the cost of recycling comes to $4.0{\euro}kg^{-1}$, while the revenue from the end-product is around $5.40{\euro}kg^{-1}$. The second process is not profitable, as well as the first one, taking into account the composition of the final oxides: the cost of recycling comes to $5.2{\euro}kg^{-1}$, while the revenue from the end-product is around $3.56{\euro}kg^{-1}$. The process becomes profitable if the final RE oxide mixture is sold for nearly $50{\euro}kg^{-1}$, a value rather far from the current market prices but not so unlikely since could be achieved in the incoming years, considering the significant fluctuations of the Res' market.

• Journal of Advanced Navigation Technology
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• v.21 no.5
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• pp.491-500
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• 2017

This paper investigates a low cost dual modular redundancy system based on heartbeat which can be applied to traffic control signal system. Failure of the traffic control signal system can cause traffic confusion and traffic accidents. Therefore safety and reliability of traffic control should be secured using fault tolerance technology. To do this, we configured a redundant board using the open source hardware and the heartbeat technique of Linux HA. The function of the traffic signal control system was verified and the fault recovery time was measured using fault injection test. As a result of the test, the fault recovery time was confirmed to be less than 9 seconds on average, confirming that the reliability target time is satisfied. Based on the results of this study, it is expected that it can be applied to fields requiring high reliability systems such as aviation, space, and nuclear power embedded systems.

• Journal of Convergence Society for SMB
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• v.3 no.2
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• pp.9-17
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• 2013

Android applications market has increased rapidly due to the popularity of smart phones. In order to high competitiveness in the application market should be high productivity, reduce cost. And short development cycle is required because of increased the android applications demand. Owing to develop applications in short time, the requirements analysis, design process are able to omitted. But in the case of reuse application at development phase, involved many problems because omit document or design. so target of this paper is android application source code that omit document or design. we propose architecture recovery techniques from android application source code by reverse engineering with identify functions are reused. We expect that increase productivity and reduce development cost, smooth maintain by proposed technique.

• Resources Recycling
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• v.29 no.2
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• pp.3-7
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• 2020

Recently, the gold leaching technologies draw much interest to recover gold from low grade ores. Current leaching processes mostly use cyanide as the leaching agent, due to its high leaching efficiencies and cost-effectiveness. However, use of cyanide is severely problematic, because of toxicity and thereby environmental risks, and requires strict regulations and environmental management. Especially, this issue becomes further apparent when cyanide should be applied for dump or heap leaching for low cost gold recovery along with recent trends. To resolve this issue, the alternative leaching processes using thiosulfate or halogen compounds, instead of cyanide, have been studied and developed but there have been lots of difficulties toward commercialization, and therefore further research should be conducted. The commercialization of dump or heap bioleaching technologies should be urgently required for effective direct biogenic gold recovery from low grade ores or tailings without use of cyanide.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.2
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• pp.75-86
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• 2002

The selection of the optimal checkpointing interval has been a very critical issue to implement a checkpointing recovery scheme for the fault tolerant distributed system. This paper presents a new scheme that allows a process to select the proper checkpointing interval dynamically. A process in the system evaluates the cost of checkpointing and possible rollback for each checkpointing interval and selects the proper time interval for the next checkpointing Unlike the other scheme, the overhead incurred by both of the checkpointing and rollback activities are considered for the cost evaluation and current communication pattern is reflected in the selection of the checkpointing interval. Moreover, the proposed scheme requires no extra message communication for the checkpointing interval selection and can easily be incorporated into the existing checkpointing coordination schemes.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.4
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• pp.377-386
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• 2019

Purpose: Percutaneous liver biopsy (PLB), a diagnostic procedure to identify several hepatobiliary disorders, is considered safe with low incidence of associated complications. While postoperative monitoring guidelines are suggested for adults, selection of procedural recovery time for children remains at the discretion of individual operators. We aim to determine if differences exist in frequency of surgical complications, unplanned admissions, and healthcare cost for children undergoing outpatient PLB for cohorts with same-day vs. overnight observation. Methods: We performed a retrospective cohort study in children 1 month to 17 years of age undergoing ultrasound-guided PLB from January 2009 to August 2017 at a tertiary care, pediatric referral center. Cohorts were defined by postprocedural observation duration: same-day (${\leq}8$ hours) vs. overnight observation. Outcomes included surgical complications, medical interventions, unscheduled hospitalization within 7 days, and total encounter costs. Results: One hundred and twelve children met study criteria of which 18 (16.1%) were assigned to same-day observation. No differences were noted in demographics, anthropometrics, comorbidities, biopsy indications, or preoperative coagulation profiles. No major complications or acute hospitalizations after PLB were observed. Administration of analgesia and fluid boluses were isolated and given within 8 hours. Compared to overnight monitoring, same-day observation accrued less total costs (US $992 less per encounter). Conclusion: Same-day observation after PLB in children appears well-tolerated with only minor interventions and complications observed within 8 hours of procedure. We recommend a targeted risk assessment prior to selection of observation duration. Same-day observation appears an appropriate recovery strategy in otherwise low-risk children undergoing outpatient PLB.

• New & Renewable Energy
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• v.16 no.4
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• pp.65-75
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• 2020

The value of tangible assets depreciates over their useful life and this depreciation should be adequately reflected in any tax or financial reports. However, the method used to calculate depreciation can impact the financial performance of solar projects due to the time value of money. Korean tax law stipulates only one method for calculating the depreciation of solar photovoltaic facilities: the straight-line method. Conversely, USA's tax law accepts other depreciation methods as solar incentives, including the modified accelerated cost recovery system (MACRS) and Bonus depreciation method. This paper compares different depreciation methods in the financial analysis of a 10 MW solar system to determine their effect on the financial results. When depreciation was calculated utilizing the MACRS and Bonus depreciation method, the internal rate of return (IRR) was 10.9% and 16.4% higher, respectively, than when the Korean straight-line depreciation method was used. Additionally, the increased IRR resulting from the use of the two US methods resulted in a 20.5% and 27.4% higher net present value, respectively. This shows that changing the depreciation calculation method can redistribute the tax amount during the project period, thereby increasing the discounted cash flow of the solar project. In addition to increasing profitability, USA's depreciation methods alleviate the uncertainty of solar projects and provide more flexibility in project financing than the Korean method. These results strongly suggest that Korean tax law could greatly benefit from adopting USA's depreciation methods as an effective incentive scheme.

• The Korean Journal of Air & Space Law and Policy
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• v.17
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• pp.29-54
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• 2003

The objectives of this study are to develop more practical and efficient model concerned with airport charge, especially with aircraft landing charge. This study utilizes average pricing and marginal pricing theory as well as cost accounting theory. The average pricing method is useful to make total costs recovery possible in uncongested situation where the marginal costs are too low to recover the total costs of service. The utilization of cost accounting theory with marginal cost pricing theory would improve the practical applicability of the model. In addition, it is necessary to apply cost accounting information in order to estimate more exact cost for the service of landing and take-off of each aircraft type.