• 전기학회논문지P
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• 제56권1호
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• pp.1-5
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• 2007

Study on the electron transport coefficient in mixtures of CF4 and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for $CF_4$ and Ar, were used. The differences of the transport coefficients of electrons in $CF_4$ mixtures of Ar, have been explained by the deduced energy distribution functions for electrons and the complete collision cross-sections for electrons. The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4-Ar$ mixtures shows the Maxwellian distribution for energy. That is, $f({\varepsilon})$ has the symmetrical shape whose axis of symmetry is a most probably energy. The proposed theoretical simulation techniques in this work will be useful to predict the fundamental process of charged particles and the breakdown properties of gas mixtures. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been used to study electron transport coefficients.

• 한국기록관리학회지
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• 제17권3호
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• pp.23-47
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• 2017

최근 조사에 의하면 공공기관이 사용하고 있는 전체 행정정보시스템의 수는 18,000여 종이 넘는다. 공공기록물 관리에 관한 법률은 모든 행정정보 데이터세트를 기록이라고 선언하고 있지만, 현행 전자기록관리정책으로 데이터세트 기록을 관리하기는 매우 어려운 실정이다. 이 논문은 데이터세트 기록을 관리하기 위한 정책방향을 제시하기 위한 것이다. 데이터세트 기록의 진본성은 기록의 내용, 구조, 맥락뿐 아니라 외형과 기능을 함께 보존함으로써 확보되며, 데이터세트를 전자객체가 아니라 전자기록으로 관리하기 위해서는 재현성이 전제되어야 함을 강조하였다. 또한 데이터세트 기록의 재현 및 장기보존 전략으로서 에뮬레이션의 가능성을 제시하였다. 이를 토대로 데이터세트 기록의 관리 모형과 정책 방향을 제안하였다.

• Nuclear Engineering and Technology
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• 제35권2호
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• pp.108-120
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• 2003

In assessing the long term post closure radiological safety assessment of a potential HLW repository in Korea, three categories of uncertainties exist. The first one is the scenario uncertainty where series of different natural events are translated into written statements. The second one is the modeling uncertatinty where different mathematical models are applied for an identical scenario. The last one is the data uncertainty which can be expressed in terms of probabilistic density functions. In this analysis, three different scenarios are seleceted; a small well scenario, a radiolysis scenario, and a naturally discharged scenario. The MASCOT-K and the AMBER, probabilistic safety assessment codes based on connection of sub-modules and a compartment theory respectively, are applied to assess annual individual doses for a generic biosphere. Results illustrate that for a given scenario, predictions from two different codes fairly match well each other But the discrepancies for the different scenarios are significant. However, total doses are still well below the guideline of 2 mRem/yr. Detailed analyses with model and data uncertainties are underway to further assure the safety of a Korean reference dispsoal concept.

• 한국환경과학회지
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• 제28권3호
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• pp.371-384
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• 2019

The purpose of this study was to propose an efficient management plan for purchased land considering the hydrological, watershed characteristics and ecological functions of the target land and surrounding area based on the result of monitoring the water quality improvement effect obtained by purchasing the land in the watershed area in the Geum river system. For this purpose, this study investigated through literature review, and examined ways to apply them to this research by deriving implications from a comprehensive analysis of previous research cases. After that, the components of assessment were derived to evaluate the ecological function of the purchase land, and the ecological function evaluation model for each land and area was proposed. In order to select purchase and restoration priorities of the land, this study analyzed the ecological status of the purchased land in main watersheds and tributaries using Arc GIS ver 10.1. Through this, a process to select restoration priorities was developed. And this study constructed the integrated management process with proposing a mid - to long - term plan by integrating the purchased land valuation and restoration priority selection process. Based on this process, this study suggested an effective management plan for purchased land through the integrated ecological management system of lands purchased. It can be used systematically in appraisal valuation, land purchase system, restoration project, and follow-up management of land purchase.

• 한국염색가공학회지
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• 제33권1호
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• pp.40-47
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• 2021

As modern society develops, it becomes very complex and diverse, and interests in the convenience of life and the natural environment are gradually increasing. Products used in our daily life are also changing according to the needs of consumers, and food packaging is one of them. In particular, retort packaging materials have been used for the purpose of long-term preservation of contents, but the appearance of products suitable for recent environmental issues has been somewhat delayed. Therefore, in order to develop eco-friendly and human-friendly products by replacing the metals used in the existing retort packaging materials, the possibility of substitution was examined using cellulose nanofibers, a natural material. As a result, it can be seen that all functions can be replaced according to the existing long-term storage characteristics for retort packaging films. In particular, not only oxygen permeability and water vapor permeability, which are one of the most important factors, but also heat resistance, which is heating durability, is evaluated as applicable to commercialization compared to products using metals currently in use.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.113-124
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• 2021

The study investigates how financial markets respond to a shock to tone and semantic similarity of the Bank of Thailand press releases. The techniques in natural language processing are employed to quantify the tone and the semantic similarity of 69 press releases from 2010 to 2018. The corpus of the press releases is accessible to the general public. Stock market returns and bond yields are measured by logged return on SET50 and short-term and long-term government bonds, respectively. Data are daily from January 4, 2010, to August 8, 2019. The study uses the Structural Vector Auto Regressive model (SVAR) to analyze the effects of unanticipated and temporary shocks to the tone and the semantic similarity on bond yields and stock market returns. Impulse response functions are also constructed for the analysis. The results show that 1-month, 3-month, 6-month and 1-year bond yields significantly increase in response to a positive shock to the tone of press releases and 1-month, 3-month, 6-month, 1-year and 25-year bond yields significantly increase in response to a positive shock to the semantic similarity. Interestingly, stock market returns obtained from the SET50 index insignificantly respond to the shocks from the tone and the semantic similarity of the press releases.

• Wind and Structures
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• 제33권6호
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• pp.423-435
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• 2021

Although existing algorithms can predict wind speed using historical observation data, for engineering feasibility, most use moment methods and probability density functions to estimate fitted parameters. However, extreme wind speed prediction accuracy for long-term return periods is not always dependent on how the optimized frequency distribution curves are obtained; long-term return periods emphasize general distribution effects rather than marginal distributions, which are closely related to potential extreme values. Moreover, there are different wind speed parent sample types; how to theoretically select the proper extreme value distribution is uncertain. The influence of different sampling time intervals has not been evaluated in the fitting process. To overcome these shortcomings, updated steps are introduced, involving parameter sensitivity analysis for different sampling time intervals. The extreme value prediction accuracy of unknown parent samples is also discussed. Probability analysis of mean wind is combined with estimation of the probability plot correlation coefficient and the maximum likelihood method; an iterative estimation algorithm is proposed. With the updated steps and comparison using a Monte Carlo simulation, a fitting policy suitable for different parent distributions is proposed; its feasibility is demonstrated in extreme wind speed evaluations at Longhua and Chuansha meteorological stations in Shanghai, China.

• Clinical and Experimental Pediatrics
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• 제64권12호
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• pp.608-618
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• 2021

Hypoxic-ischemic encephalopathy (HIE) is the most common cause of neonatal encephalopathy with a global incidence of approximately 1 to 8 per 1,000 live births. Neonatal encephalopathy can cause neurodevelopmental and cognitive impairments in survivors of hypoxic-ischemic insults with and without functional motor deficits. Normal neurodevelopmental outcomes in early childhood do not preclude cognitive and behavioral difficulties in late childhood and adolescence because cognitive functions are not yet fully developed at this early age. Therapeutic hypothermia has been shown to significantly reduced death and severe disabilities in term newborns with HIE. However, children treated with hypothermia therapy remain at risk for cognitive impairments and follow-up is necessary throughout late childhood and adolescence. Novel adjunctive neuroprotective therapies combined with therapeutic hypothermia may enhance the survival and neurodevelopmental outcomes of infants with HIE. The extent and severity of brain injury on magnetic resonance imaging might predict neurodevelopmental outcomes and lead to targeted interven tions in children with a history of neonatal encephalopathy. We provide a summary of the long-term cognitive outcomes in late childhood and adolescence in children with a history of HIE and the association between pattern of brain injury and neurodevelopmental outcomes.

• 셀메드
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• 제12권3호
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• pp.11.1-11.5
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• 2022

Bell's Palsy is one of the most common mononeuropathies or disorders affecting a single nerve and is associated with facial nerve weakness and paralysis. Though self-limiting the disorder may leave its long-lasting residual manifestations in the form of abnormal facial symmetry, inability to close the eyes, and other poor outcomes leading to disability and impairment in societal functioning among patients. Treatment strategies include pharmacological, surgical, and therapeutic options and to limit the long-term devastating effects therapeutic options play a vital role. Physiotherapeutic techniques have been widely used among patients with Bell's Palsy but not all techniques are performed in combination. One is compared with the other and also for short durations. We planned this study to see the outcome of combined techniques available in Physiotherapy on a patient with long-term follow-up. This is a case of 38 years old male patient diagnosed with right-sided bell palsy who received 7 weeks of rehabilitation in the form of electrotherapy, facial exercises, facial PNF, massage, and education on eye care. The implementation of 7 weeks of physiotherapeutic rehabilitation led to improved facial functions and a reduction in the level of disability in the patient.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권3호
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• pp.896-915
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• 2023

The network function virtualization (NFV) uses virtualization technology to separate software from hardware. One of the most important challenges of NFV is the resource management of virtual network functions (VNFs). According to the dynamic nature of NFV, the resource allocation of VNFs must be changed to adapt to the variations of incoming network traffic. However, the significant delay may be happened because of the reallocation of resources. In order to balance the performance between delay and quality of service, this paper firstly made a compromise between VNF migration and energy consumption. Then, the long short-term memory (LSTM) was utilized to forecast network traffic. Also, the asymmetric loss function for LSTM (LO-LSTM) was proposed to increase the predicted value to a certain extent. Finally, an experiment was conducted to evaluate the performance of LO-LSTM. The results demonstrated that the proposed LO-LSTM can not only reduce migration times, but also make the energy consumption increment within an acceptable range.