• 방사성폐기물학회지
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• 제18권4호
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• pp.517-536
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• 2020

The radionuclide inventory in radioactive waste from nuclear power plants should be determined to secure the safety of final repositories. As an alternative to time-consuming, labor-intensive, and destructive radiochemical analysis, the indirect scaling factor (SF) method has been used to determine the concentrations of difficult-to-measure radionuclides. Despite its long history, the original SF methodology remains almost unchanged and now needs to be improved for advanced SF implementation. Intense public attention and interest have been strongly directed to the reliability of the procedures and data regarding repository safety since the first operation of the low- and intermediate-level radioactive waste disposal facility in Gyeongju, Korea. In this review, statistical methodologies for SF implementation are described and evaluated to achieve reasonable and advanced decision-making. The first part of this review begins with an overview of the current status of the scaling factor method and global experiences, including some specific statistical issues associated with SF implementation. In addition, this review aims to extend the applicability of SF to the characterization of large quantities of waste from the decommissioning of nuclear facilities.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• 제60권3호
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• pp.99-106
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• 2017

Listening effort is defined as a listener's mental exertion required to understand a speaker's auditory message, especially when distracting conditions are present. This review paper analyzed several subjective scaling tools used to measure the listening effort in order to suggest the best tool for use with hearing-impaired listeners who have to expend much effort even in everyday life. We first explained the importance of measuring listening effort and discussed various kinds of measurements. We then analyzed and categorized 15 recently published articles (i.e., from 2014 to 2016) into three topics: performance and listening effort, listening effort and fatigue, and clinical implication of listening effort. We compared the articles in terms of pros and cons and also identified 10 tools for use in the subjective scaling. Although none of these tools were unified or standardized easily, we concluded that 7-point scale would be the most reasonable as a less time-consuming measurement for compartmentalizing the degree of listening effort. If used with objective tools for measuring the listening effort, the subjective scaling could be a powerful tool for clinical use.

• 한국정밀공학회지
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• 제19권9호
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• pp.74-81
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• 2002

Recently tube hydroforming has been widely applied to the automotive industries due to its several advantages over conventional methods. In this paper, attention is paid to comparison of an implicit and an explicit finite element method widely used for numerical simulation of a hydroforming process. For an explicit FEM, a huge amount of computational time is required because of the very small time increment to solve a quasi-static problem. Hence, when an explicit FEM is used fDr a hydroforming process, it is general to convert the real problem to a virtual problem with a different processing time and mass density by appropriate scaling factor. However it is difficult to figure out how large the scaling should be adopted enough to ignore the dynamic effects and maintain the desired accuracy. In this paper, the comparison of the results obtained from both methods focus on the accuracy of the predicted geometrical shape and the stress with various scaling factors which are applied to analyze hydroforming process of an automobile lower arm.

• 대한치과재료학회지
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• 제43권1호
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• pp.17-28
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• 2016

The aim of this study was to evaluate the changes in dentinal permeability after application of dentin desensitizer on exposed dentin immediately after ultrasonic scaling to teeth with non-carious cervical lesions. Thirty caries-free extracted molars were fixed to slide glasses after horizontally being sectioned at 5 mm below the cemento- enamel junction (CEJ). The prepared specimen was connected to a fluid flow measuring device (nano-Flow), and a V-shaped cavity was formed at the CEJ to imitate the non-carious cervical lesion. After no fluid leakage was confirmed in the connected system with specimen, tooth surface was treated ultrasonic cleaning with piezoelectric ultrasonic scalers until dentinal tubules were exposed. And 6 different desensitizers were applied on exposed dentin. Real-time measurements of dentinal fluid flow were performed during ultrasonic scaling and application of dentin desensitizer. To evaluate the occlusion of exposed dentinal tubules, tooth surface was examined by SEM. Following results were observed. After ultrasonic scaling, more dentinal tubules were exposed on the tooth with non-carious cervical lesions compared to tooth without lesions. The rate of fluid flow measured with nano-Flow system had correlation with the degree of dentin occlusion observed with SEM after application of desensitizers on exposed dentin. Desensitizers with glutaraldehyde and HEMA did not decrease the rate of fluid flow and did not show dentin occlusion. Desensitizers with oxalate showed the limited effects on the rate of fluid flow and dentinal tubule occlusion. Desensitizer with resin monomer showed the significant effect on the rate of fluid flow and dentin occlusion.

• 말소리와 음성과학
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• 제7권4호
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• pp.139-145
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• 2015

The present study investigates the effects of syllable structure and prosodic prominence on the patterns of tonal alignment and scaling of the phrase-initial rise in Seoul Korean. Two syllable structures (Onset (/#CVC.../ as in minsa) vs. No-onset (/#VC.../ as in insa)) and two prominence conditions (Focus vs. Neutral) were considered. Results showed that the alignment of the L and the H tones in the phrase-initial rise was affected by syllable structure but not by prominence. The time of L was before the vowel onset of the first syllable in the Onset condition (i.e., within the onset consonant) and it was after the vowel onset in the No-onset condition. The difference was attributable to the fact that the initial L was anchored at a fixed distance from the phrase boundary, which was about 30ms after the onset of the syllable in both cases. The time of H was also consistently observed about 20ms after the second vowel onset (i.e., /a/ in minsa/insa). Moreover, the rise time (the duration from the L to the H tones) was longer as the local syllable duration became longer due to different syllable structure and prominence conditions. Taken together, the results provide a support for the segmental anchoring hypothesis, which claims that both the beginning and the end of F0 movement are consistently aligned with segmental 'anchor' points with relatively high stability (Ladd et al., 1999). Results also showed that the scaling of the early rise was slightly influenced by syllable structure but not by prominence. The differences between the results of the current study and a previous study (Cho, 2011) are further discussed.

• 한국인터넷방송통신학회논문지
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• 제17권2호
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• pp.1-6
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• 2017

최근 사물인터넷의 급부상으로 배터리 기반 사물인터넷 기기를 위한 전력절감 기술이 주목받고 있다. 사물인터넷 기기는 일종으로 실시간시스템으로, 전력절감을 위해 프로세서의 전압을 동적으로 조절하는 방법이 각광받아왔으나, 최근 연구에 따르면 전력소모 중 메모리가 차지하는 비중이 급격히 증가한 것으로 분석되고 있다. 이에 본 논문은 프로세서의 전압조절 기법에 저전력 비휘발성메모리 기술을 결합하여 실시간시스템의 전력소모를 더욱 줄이고자 한다. 이는 낮은 전압의 프로세서로 태스크의 스케줄링이 가능한 시점에는 메모리의 성능이 낮아지더라도 여전히 스케줄링이 가능성할 것이라는 점에 착안한 것이다. 본 논문은 이기종메모리 상의 태스크 할당 문제를 프로세서의 전압조절 기법과 결합한 후 두 기법의 전력절감 효과를 분석하고, 이들을 결합하여 전력절감을 극대화한다.

• Journal of Periodontal and Implant Science
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• 제48권1호
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• pp.3-11
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• 2018

Purpose: This study utilized a strong quasi-experimental design to test the hypothesis that the implementation of a policy to expand dental care services resulted in an increase in the usage of dental outpatient services. Methods: A total of 45,650,000 subjects with diagnoses of gingivitis or advanced periodontitis who received dental scaling were selected and examined, utilizing National Health Insurance claims data from July 2010 through November 2015. We performed a segmented regression analysis of the interrupted time-series to analyze the time-series trend in dental costs before and after the policy implementation, and assessed immediate changes in dental costs. Results: After the policy change was implemented, a statistically significant 18% increase occurred in the observed total dental cost per patient, after adjustment for age, sex, and residence area. In addition, the dental costs of outpatient gingivitis treatment increased immediately by almost 47%, compared with a 15% increase in treatment costs for advanced periodontitis outpatients. This policy effect appears to be sustainable. Conclusions: The introduction of the new policy positively impacted the immediate and long-term outpatient utilization of dental scaling treatment in South Korea. While the policy was intended to entice patients to prevent periodontal disease, thus benefiting the insurance system, our results showed that the policy also increased treatment accessibility for potential periodontal disease patients and may improve long-term periodontal health in the South Korean population.

• 한국토양비료학회지
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• 제46권5호
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• pp.359-364
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• 2013

This study was conducted to develop a model to estimate crop leaf surface temperature. The results were as following; A definition for the daily time based on elapsed time from the midnight (00:00) as "E&E time" with the unit of Kmin. was suggested. The model to estimate the scaled temperature ($T^*e$) of crop leaf surface temperature by scale factor ($T^*$) according to the "E&E time : Kmin."(X) was developed as eq. (1) $T^*e=0.5{\cdot}sin(X+780)+0.5$ (2) $T^*=(Tx-Tn)/(Tm-Tn)$, Tx : Daily leaf temperature, Tm : Daily maximum leaf temperature, Tn : Daily minimum leaf temperature. Relative sensitivity of the measured temperature compared to the estimated temperature of red pepper, soybean and persimmon was 1.078, 1.033 and 0.973, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.438-440
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• 2004

Energy consumption has become an increasingly important consideration in designing real-time embedded systems. In this paper, we propose a voltage scaling method to reduce energy consumption in fixed priority real-time systems using variable voltage processors. The Hyperperiod of tasks is divided into dimains. The most suitable voltage of each domain is determined off-line and stored in a table. During task execution, the voltage of processor is adjusted according to the information of the table. A simulation result shows that the proposed method can reduce 80% of power consumption in comparison to no power management. The difference to the optimal EDF based method is only 5%.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.985-987
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• 2011

본 논문은 파생형엔진의 설계를 위해 시동시간 예측모델을 개발하는 경우를 다루었다. 파생형엔진 설계를 위해 압축기/터빈의 특성맵을 새로 제안한 Modified Pump Scaling Law(MPS)방법을 사용하여 시동모델링에 필요한 아이들 이하 회전수(sub idle rpm) 영역으로 확장시켰고, 기준엔진의 손실특성에서 압력/온도와 엔진별 특성차이를 고려한 파생형엔진의 손실모델을 도출하였다. 이러한 특성을 반영한 파생형엔진의 시동시간 예측모델은 시험결과와 비교하여 비교적 양호한 결과를 나타내었다.