• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.10
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• pp.871-876
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• 2016

Abnormal odor similar with burning smell often appears at the cockpit in the beginning of ultra-sonic aircraft without air filter due to the heating of production materials remained at the bleed air duct. Sources of the odor should be removed by burn-in test before test flight in order to prevent pilot confuses order with emergency such as fire of engine. However, the present method cannot prevent abnormal odor completely at the high altitude flight because maximum temperature of flight is higher than it of burn-in-test. This paper suggests burn-in test improved based on the analysis of thermal conditions of high altitude flight. It is verified that the existing burn-in test cannot cover thermal conditions of high altitude flight due to the discontinuous flow control, high change rate of temperature per unit time and difference between limit temperature of condenser and turbine. In order to overcome the limitations of current methods, the new burn-in test with continuous flow control are suggested. The continuous flow control are achieved by ram air inlet control. The effect of suggested method are verified by ground tests and flight tests. The results show the bleed air temperature can cover the temperature of high altitude flight and prevent abnormal odor at the flight test.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.165-172
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• 2007

A space launch vehicle is a very complex system composed of many kinds of components. It is necessary for even a small piece of components in it to be free of defects, malfunctions and to operate normally for the sake of the mission success. For these reasous, a variety of tests are carried out. Burn-in test is to detect latent material and workmanship defects which occurs early in the components use. Developed countries for the space technology have considered the burn-in test for flight vehicles in the standard test documents and performed it. Referred to the documents, application methods of burn-in test will be considered for the components of domestic space launch vehicles such as KSLV-I in this document.

• Journal of Korea Foundry Society
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• v.3 no.2
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• pp.100-105
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• 1983

The mechanism of coal-dust action on inhibiting burn-on of Sand to iron castings was taken in consideration by means of casting test and thermal decomposition test. To compare the ability of inhibiting sand burn-on, test castings were produced in green sand moulds added three different coal-rusts. And quantitative determination of lustrous carbon and volatiles production for coal-dust samples were performed.The lustrous carbon production was in good agreement with the casting test result. But total voltiles production was relatively inefficient on hibiting sand burn-on to test castings.The lustrous carbon theory can be given to explain the mechanism which coal-dust inhibits sand burn-on to iron castings.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.275-285
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• 2016

The purpose of this study is to identify the factors influencing on the burden on the family caregivers of patient with more than second degree burn. The participants of this study were 120 family caregivers sampled for convenience from 4 Burn hospitals in D, S, B, P cities in South Korea. Data analysis was performed by t-test, ANOVA, Scheffe' test, Multiple linear regression. According to the result, the burden of assess & mean of care and the future of the patient was the highest score for family caregivers. Factors that affect the burden of family caregiver with burn patients were marital status, time, care, skin transplants, body surface area (%) and these factors explained 25.9%. This study concludes that intervention program is developed to reduce physical and emotional burden and nursing care services is required to adjust the amount time to care for the family caregivers with burn patients for a long time.

• IE interfaces
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• v.18 no.3
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• pp.350-360
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• 2005

This paper considers a strategy for planning of rework in semiconductor monitoring burn-in test process. The equipment error in monitoring burn-in test process generates many defects. These defects are transformed into good products by rework process, i.e. retest. Rework has the advantage of saving production costs. But rework increases holding costs and incurs rework costs. In monitoring burn-in test process, rework depends on operator's experience with no pre-defined specification. In practice, a number of rework activities are performed with respect to the product importance and inventory quantity. Moreover, disregard for order jobs schedule have caused due date penalties. So a strategy for planning of rework by which order jobs schedule are not affected is suggested. Futhermore, production costs, rework costs and inventory costs for planning of rework are considered.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.9
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• pp.1-9
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• 1994

This paper analyzes the faults and their mechanism of CMOS ICs using IDDQ testing technique and evalutes the reliability of the chips that fail this test. It is implemented by the three testing phases, initial test, burn-in and life test. Each testing phase includes the parametric test, functional test, IDDQ test and propagation delay test. It is shown that the short faults such as gate-oxide short, bridging can be only detected by IDDQ testing technique and the number of test patterns for this test technique is very few. After first burn-in, the IDDQ of some test chips is decreased, which is increased in conventional studies and in subsequent burn-in, the IDDQ of all test chips is stabilized. It is verified that the resistive short faults exist in the test chips and it is deteriorated with time and causes the logic fault. Also, the new testing technique which can easily detect the rsistive short fault is proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.75-80
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• 2009

Bum-in test is one for eliminating semiconductor devices that are subject to early failures and other operational problems; it is usually carried out on the devices by imposing severe test conditions such as elevated voltages, temperatures, and time. In order for such a test to be performed, each burn-in board having devices to be tested, needs to be inserted into a corresponding slot. A set of such slots is called a zone. The slots comprising a zone can only have the burn-in boards with the devices of the same type. In order to test many different types of semiconductor devices, it is desirable to build a burn-in test system to have as many zones as possible. A zone controller controlling a zone, is a device that performs a burn-in test and collects test results. In case of existing systems, each zone controller takes care of a zone that consists of a fixed number of slots. Since a zone controller is, in most cases, embedded into a workstation that controls the overall testing process, adding new zone controllers is restricted by the spaces for them. As a way to solve or alleviate these problems, a dynamic zone system in which the number of slots in a zone can be dynamically allocated, is presented. This system maximizes the efficiency of system utilization, by altering the number of slots and hence minimizing the idle slots of a zone. In addition, all the test operations being performed must be aborted for maintenance in existing systems. In dynamic zone systems, however, a separate and independent maintenance is allowed for each slot, as long as the main power supply system has no problem.

• Journal of Korean Academy of Nursing
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• v.17 no.3
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• pp.227-240
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• 1987

Infection has assumed increased importance as a cause of death among thermally injured individuals. Decreased treatment effectiveness and an increase in mortality are the hallmarks of nosocomial infection. Infection control is a monumental task that must be achieved to reduce mortalities. This was a retrospective study to survey the epidemiological features of nosocomial infections in a burn unit and to identify the possibilities for infection control. During the past 6 year 2 month period from July, 1981 to August, 1987, 306 burn patients were treated in the burn unit of university hospital. Among of these, 290 cases were the subjects of this study. The data were collected from the patients' records after discharge. All data collected were analyzed using percent, x$^2$-test, t-test with SPSS program. The results of this study are summariged as follows: 1) Infection rate was 40%. According to site, there were 67 cases of wound infection, 60 cases of post-operative skin graft infection, 20 cases of septicemia and 20 cases of donor site infection. As far as the burn size was concerned, the infection rate for patients whose burn size ranged 61 to 70%, was shown to be 100%, followed by the infection rate of 93.8%, for patients whose burn size ranged from 41~50%. As far as the period of time over which the infection developed, 5 to 7 days showed the highest frequency. Further infection was the main cause of deaths and complications. 2) Based upon the results obained by comparing the general characteristics, between a hospital infection-group and non-hospital infection group, there was a significant defference according to age, the time of the year when the accident happened, the place of accident or length of hospital-admission. And according to the result obtained by comparing the general characteristics of the burn, there was a significant difference according to burn size, burn depth, burn type, and burn site. And also based upon the result obtained by comparing the two groups according to method of treatment, there was a significant difference according to the use of antibiotics and to the type of wound-treatment, and for the 8 different binds of treatment related to infection, there was a significant difference for all. In conclusion, age, length of hospital-admission, burn size, burn type, burn site, burn depth, type of woundtreatment and the 8 different binds of treatment, which are related to burns, were shown to be the factors which affect the infection rate in burn patients.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.107-113
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• 2024

Scheduling of semiconductor test facilities has been crucial since effective scheduling contributes to the profits of semiconductor enterprises and enhances the quality of semiconductor products. This study aims to solve the scheduling problems for the wafer burn-in test facilities of the semiconductor back-end process by utilizing simulation and deep reinforcement learning-based methods. To solve the scheduling problem considered in this study. we propose novel state, action, and reward designs based on the Markov decision process. Furthermore, a neural network is trained by employing the recent RL-based method, named proximal policy optimization. Experimental results showed that the proposed method outperformed traditional heuristic-based scheduling techniques, achieving a higher due date compliance rate of jobs in terms of total job completion time.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1893-1908
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• 2021

In light of the importance of helium production in influencing the behaviour of fast reactor fuels, in this work we present a burn-up module with the objective to calculate the production of helium in both in-pile and out-of-pile conditions tracking the evolution of 23 alpha-decaying actinides. This burn-up module relies on average microscopic cross-section look-up tables generated via SERPENT high-fidelity calculations and involves the solution of the system of Bateman equations for the selected set of actinide nuclides. The results of the burn-up module are verified in terms of evolution of actinide and helium concentrations by comparing them with the high-fidelity ones from SERPENT, considering two representative test cases of (U,Pu)O₂ fuel in fast reactor conditions. In addition, a code-to-code comparison is made with the independent state-of-the-art module TUBRNP (implemented in the TRANSURANUS fuel performance code) for the same test cases. The herein presented burn-up module is available in the SCIANTIX code, designed for coupling with fuel performance codes.