• Journal of information and communication convergence engineering
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• v.10 no.1
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• pp.53-60
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• 2012

Attribute-based encryption (ABE) is an encryption scheme in which the user is able to decrypt a ciphertext with associated attributes. However, the scheme does not offer the capability of decryption to others when the user is offline. For this reason, the attribute-based proxy re-encryption (ABPRE) scheme was proposed, which combines traditional proxy re-encryption with ABE, so a user is able to empower designated users to decrypt the re-encrypted ciphertext with the associated attributes of designated users. However, previous ABPRE schemes demands a number of pairing operations that imply huge computational overhead. To reduce the number of pairing operations, we reduce the pairing operations with exponent operations. This paper provides a novel approach to an ABPRE scheme with constant pairing operation latency.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.150-158
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• 2013

In Korea, the official monitoring of the atmospheric re-entry of satellites or space debris was initiated by the first operation of a re-entry situation analysis team for the 'Cosmos 1402' of the Soviet Union, which main body re-entered on January 23, 1983 and radio active core re-entered on February 7, 1983. After this incident, a task force team consisting Korea Astronomy and Space Science Institute (KASI), Korea Aerospace Research Institute (KARI) and other related institutes operated a situation monitoring group under the supervision of the Ministry of Science and technology (MOST) for the controlled re-entry of the Russian 'Mir' space station in 2001. The re-entry of the upper atmospheric weather satellite 'UARS' of United States had been monitored and analyzed by KASI on September 24, 2011. As the re-entry of the space object has been frequently occurred, the government officials and the experts from MEST (Ministry of Education, Science and Technology), KASI, KARI had an urgent official meeting to establish a satellite re-entry monitoring room in KASI and to give an operational authority to KASI in September 14, 2011. Under this decision, the satellite re-entry monitoring room in KASI has successfully executed the monitoring, data analyzing, official reporting, media contacting, and public announcing for the German satellite 'Roentgen' in October 2011, Russian space explorer 'Phobos-Grunt' in January 2012, Russian satellite 'Cosmos 1484' in January 2013, and European geodetic satellite 'GOCE' in November 2013 with the support from the Korean Air Force and KARI.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.4 no.2
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• pp.245-265
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• 1997

The purpose of this study was to promote the effectiveness in managing disease or injury, by examining the length of stay in hospital according to characteristics concerned before and after operation, and by serving as a basis for reducing that length. As a result of investigating the length of stay in hospital according to inpatient's personal characteristics, clinical features and other characteristics concerned, the following characteristics appeared significant. The characteristics that showed a significant difference about the length of stay in hospital before and after operation were the age and the fact whether one was married or not among inpatient's personal characteristics. The significant ones among clinical features were the route to be taken to hospital, the form of insurance, the experience of re-hospitalization, whether another disease coexisted, the experiment of changing department, whether a diagnosis was determined by consultation, whether an intensive care unit was used, whether re-operation was performed, the total number of case of the experience of re-hospitalization, inpatient who were again sent to hospital under the same diagnosis was not included in the investigation, which was pointed out as a limit in this study. The significant ones among other characteristics concerned were the date and season when the patients were taken to hospital and the doctor in attendance. The doctor in attendance appeared to give a significant impact on the length of stay in hospital before operation, but no significant difference was noted in the mean among the doctors in attendance. And those characteristics were not found regularly among the selected departments. As stated above, one way to reduce the length of stay In hospital was to diminish the length of stay in hospital before operation. The term of hospitalization before operation shall be reduced by grasping the factors that affected that length before operation and by conducting examination as many as possible in the out-patient department. Also, the efforts should be put on that length after operation. The management of hospital seemed to be successfully carried out if those factors affected that length were effectively controlled.

• Journal of Radiation Protection and Research
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• v.43 no.3
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• pp.124-129
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• 2018

Background: Effluent Concentration Limits (ECLs) were re-evaluated via direct calculation using dose coefficients based on radiation protection quantity introduced in Korea and the intrinsic breathing rates of Korean residents. Materials and Methods: The re-evaluated ECLs were compared with the domestic standards given in the Notice of the Nuclear Safety and Security Commission (NSSC), as well as with ECLs specified in the Code of Federal Regulations (CFR). Results and Discussion: The relative ratios of the re-evaluated ECLs to the currently applied domestic standards differed depending on the radionuclide type, but it was clearly shown that, for tritium ($^3H$) and radiocarbon ($^{14}C$), which significantly affect radiological dose to the public during the normal operation of nuclear power plants, the re-evaluated ECLs were higher than the domestic standards. This implies that Korean standards are relatively conservative. Conclusion: The re-evaluated results for each age group showed that $^{131}I$ (radioiodine), one of the significant radionuclides, had the lowest values, but nonetheless, the domestic standards for radioiodine were lower than the ECLs given in the CFR and the re-evaluated ECLs via a method given in the CFR.

• International Journal of Automotive Technology
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• v.8 no.2
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• pp.243-248
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• 2007

The durability of a cylinder head is influenced by the thermal and mechanical history during the manufacturing process, as well as engine operation. In order to improve the durability of cylinder head, both load from engine operation and the preload conditions from the manufacturing process must be considered. The aluminum cylinder head used for a HSDI diesel engine is investigated to reduce the possibility of high cycle fatigue crack in this study. FE analysis is performed to elucidate the mechanism of high cycle fatigue crack in the HSDI diesel cylinder head. Two separate approaches to increase the durability of the cylinder head are discussed: reducing load from engine operation and re-arranging preload conditions from the manufacturing process at the critical location of the cylinder head. Local design changes of the cylinder head and modification of pretension load in the cylinder head bolt were investigated using FE analysis to relieve load at the critical location during engine operation. Residual stress formed at the critical location during the manufacturing process is measured and heat treatment parameters are changed to re-arrange the distribution of residual stress. Results of FE analysis and experiments showed that thorough consideration of the manufacturing process is necessary to enhance the durability of the cylinder head.

• Hip & pelvis
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• v.34 no.4
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• pp.262-268
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• 2022

A fracture of the affected extremity in patients with Klippel-Trenaunay-Weber syndrome can be fatal due to massive bleeding and show poor results. A 42-year-old male presented with an old fracture of the right femoral shaft with metal failure. We planned an operation to remove the previously fixed plate and to perform re-fixation using an intra-medullary nail. Preoperative angiography was performed and the arteriovenous malformations were embolized in order to reduce the risk of bleeding. After angiography, the previously fixed plate was removed. After the operation, a second angiography was performed immediately and the venous malformation was embolized. One week after the first operation, a second operation was performed in order to reduce the fracture and to perform re-fixation using an intramedullary nail. The patient is being followed without major complication over a period of seven years after surgery. We recommend careful planning of preoperative and postoperative angiography and embolization in order to reduce the risk of bleeding in patients with Klippel-Trenaunay-Weber syndrome.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.296-303
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• 2002

The main subject to become a hub port is automation. The automated container terminal has already operated in advanced ports and it has been planned for the basic planning and operation design in domestic case. The key of automated container terminal is effective operation of both ATC(automated transfer crane) and AGV(automated guided vehicle) which is automated handling equipments. This is essential to poductivity of automated container terminal. This study suggests the most optimal method of equipment operation in order to minimize loading time using each three types of effective ATC operation methods and AGV dispatching rules in automated container terminals. As the automated equipment operation causes unexpected deadlocks or interferences, it should be proceeded on event-based real time. Therefore we propose the most effective ATC operation methods and AGV dispatching rules in this paper. The various states occurred in real automated container terminals are simulated to evaluate these methods. This experiment will show the most robust automated equipment operation method on various parameters(the degree of yard re-marshaling, the number of containers and the number of AGVs)

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.296-303
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• 2002

The main subject to become a hub port is automation. The automated container terminal has already operated in advanced ports and it has been planned for the basic planning and operation design in domestic case. The key of automated container terminal is effective operation of both ATC(automated transfer crane) and AGV(automated guided vehicle) which is automated handling equipments. This is essential to productivity of automated container terminal. This study suggests the most optimal method of equipment operation in order to minimize loading time using each three types or effective ATC operation methods and AGV dispatching rules in automated container terminals. As the automated equipment operation causes unexpected deadlocks or interferences, it should be proceeded on event-based real time. Therefore we propose the most effective ATC operation methods and AGV dispatching rules in this paper. The various states occurred in real automated container terminals are simulated to evaluate these methods. This experiment will show the most robust automated equipment operation method on various parameters(the degree of yard re-marshaling, the number of containers and the number of AGVs)

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.46-49
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• 2006

Extinction limits and combustion temperatures in heat-recirculating excess enthalpy reactors employing both gas-phase and catalytic reaction have been examined previously, with and emphasis Reynolds number (Re) effects and possible application to microscale combustion devices. However, Re is not the only parameter needed to characterize reactor operation. In particular, the use of a fixed reactor size implies that residence time and Re cannot be adjusted independently. To remedy this situation, in this work geometrically similar reactors of different physical sizes were tested with the aim of independently determining the effects of Re and Da. It is found that the difference between catalytic and non-catalytic combustion limits narrow as scale decreases. Moreover, to assess the importance of wall thermal conductivity, reactors of varying wall thickness were studied. From these results the effect of scale on microscale reactor performance and implications for practical microcombustion devices are discussed.

• The Journal of Industrial Distribution & Business
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• v.3 no.2
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• pp.17-21
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• 2012

Purpose - The objective of the paper is to explain the factors affecting on the Re-contract intension of franchisor in the uprising Chinese franchise market. Research design, data, methodology - The study conducted a survey on the 400 franchisors data in China from January to July 2012. By AMOS analyzing the data to examine these hypotheses empirically, we can confirm most hypothesis supposed. Results - This study shows that the high management performance and satisfaction of the franchise headquarters has a positive effect on the Re-contract intention of franchise. In the case of large markets such as China, the franchisor's strategy and the role is very important. Conclusions - This study provides franchisors and practitioners, who plan to extend their franchising business abroad into Chinese market, with some practical knowledge. in order to achieve stable profits, the franchise corporation needs to support the operation of the individual franchisee through incentives and standardization of services.