• Journal of Communications and Networks
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• v.14 no.5
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• pp.566-577
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• 2012

In randomly deployed networks, such as sensor networks, an important problem for each node is to discover its neighbor nodes so that the connectivity amongst nodes can be established. In this paper, we consider this problem by incorporating the physical layer parameters in contrast to the most of the previous work which assumed a collision channel. Specifically, the pilot signals that nodes transmit are successfully decoded if the strength of the received signal relative to the interference is sufficiently high. Thus, each node must extract signal parameter information from the superposition of an unknown number of received signals. This problem falls naturally in the purview of random set theory (RST) which generalizes standard probability theory by assigning sets, rather than values, to random outcomes. The contributions in the paper are twofold: First, we introduce the realistic effect of physical layer considerations in the evaluation of the performance of logical discovery algorithms; such an introduction is necessary for the accurate assessment of how an algorithm performs. Secondly, given the double uncertainty of the environment (that is, the lack of knowledge of the number of neighbors along with the lack of knowledge of the individual signal parameters), we adopt the viewpoint of RST and demonstrate its advantage relative to classical matched filter detection method.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.541-550
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• 2022

When decommissioning nuclear power plant (NPP), the first task performed is cost estimation. This is an important task in terms of securing adequate decommissioning funds and managing the schedule. Therefore, many countries and institutions are conducting continuous research and also developing and using many programs for cost estimation. However, the cost estimated for decommissioning an NPP typically differs from the actual cost incurred in its decommissioning. This is caused by insufficient experience in decommissioning NPPs or lack of decommissioning cost data. This uncertainty in cost estimation can be in general compensated for by applying a contingency. However, reflecting an appropriate standard for the contingency is also difficult. Therefore, in this study, data analysis was conducted based on the contingency guideline suggested by each institution and the actual cost of decommissioning the NPP. Subsequently, TLG Service, Inc.'s process, which recently suggested specific decommissioning costs, was matched with ISDC (International Structure for Decommissioning Costing)'s work breakdown structure (WBS). Based on the matching result, the guideline for applying the contingency for ISDC's WBS Level 1 were presented. This study will be helpful in cost estimation by applying appropriate contingency guidelines in countries or institutions that have no experience in decommissioning NPPs.

• The Journal of Small Business Innovation
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• v.19 no.3
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• pp.17-42
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• 2016

Financial Accounting Standards Board (FASB) Interpretation No. 48 (FIN 48), Accounting for Uncertainty in Income Taxes: An interpretation of FASB Statement No. 109, requires firms to evaluate uncertain tax positions and disclose information on their liabilities for these positions, unrecognized tax benefits (UTBs). We analyze the FIN 48 disclosures for calendar-year-end Korean companies listed on NYSE and NASDAQ and examine the Korean firms' tax aggressiveness utilizing the UTBs. The results suggest that stock exchange and firm size do not play a role in the Korean firms' tax aggressiveness, contrary to the matched U.S. firms and that the Korean firm in the miscellaneous retail industry is more tax aggressive than the firms in the communications, depository institutions and business services. In addition, we find evidence that the Korean firms are less tax aggressive than the matched U.S. firms. We also examine the Korean firms' tax avoidance tendencies using other measures of avoidance, leading to mixed results. Finally, we examine the association between the UTBs and other measures of tax avoidance and find a significant and negative association between the UTBs and the long-run cash effective tax rate.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.3
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• pp.30-39
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• 2011

In this note, a systematic design of a new robust nonlinear continuous variable structure control system(VSCS) based on the modified state dependent nonlinear form is presented for the control of uncertain affine nonlinear systems with mismatched uncertainties and matched disturbance. After an affine uncertain nonlinear system is represented in the form of state dependent nonlinear system, a systematic design of a new robust nonlinear VSCS is presented. The uncertainty of the nonlinear system function is separated into the tow parts, i.e., state dependent term and state independent term for extension of target plants. To be linear in the closed loop resultant dynamics and in order to easily satisfy the existence condition of the sliding mode, the transformed linear sliding surface is applied. A corresponding control input is proposed to satisfy the closed loop exponential stability and the existence condition of the sliding mode on the linear transformed sliding surface, which will be investigated in Theorem 1. For practical application, the discontinuity of the control input as the inherent property of the VSS is improved dramatically. Through a design example and simulation studies, the usefulness of the proposed controller is verified.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5493-5498
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• 2015

Due to the lack of nationwide population-based cancer registration, the total cancer prevalence in Iran is unknown. Our previous work in which we used a basic network scale-up (NSU) method, failed to provide plausible estimates of total cancer prevalence in Kerman. The aim of the present study was to estimate total and partial prevalence of cancer in southeastern Iran using an adapted version of the generalized network scale-up method. A survey was conducted in 2014 using multi-stage cluster sampling. A total of 1995 face-to-face gender-matched interviews were performed based on an adapted version of the NSU questionnaire. Interviewees were asked about their family cancer history. Total and partial prevalence were estimated using a generalized NSU estimator. The Monte Carlo method was adopted for the estimation of upper/lower bounds of the uncertainty range of point estimates. One-yr, 2-3 yr, and 4-5 yr prevalence (per 100,000 people) was respectively estimated at 78 (95%CI, 66, 90), 128 (95%CI, 118, 147), and 59 (95%CI, 49, 70) for women, and 48 (95%CI, 38, 58), 78 (95%CI, 66, 91), and 42 (95%CI, 32, 52) for men. The 5-yr prevalence of all cancers was estimated at 0.18 percent for men, and 0.27 percent for women. This study showed that the generalized familial network scale-up method is capable of estimating cancer prevalence, with acceptable precision.

• Journal of Korean society of Dental Hygiene
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• v.18 no.6
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• pp.1067-1077
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• 2018

Objectives: The purpose of the study is to investigate the opinions of some local clinical dental hygienists on medical personnel of dental hygienists. It will be for provide the Future dental hygienist basic data necessary for medical personnel. Methods: A self-reported questionnaire was completed by 171 dental hygienists in Busan and Gyeongnam from December 1, 2017 to January 31, 2018. Structured questionnaires were uesd for analysis. The questionnaire consisted of general characteristics of the subjects(7 items), medical personnel necessity and opinions of dental hygienist(2 items), the opinions of distinction of the task between dental hygienists and other personnel(2 items), many frequency task in the dental clinic. The collected data were analyzed using frequency, percentage, descriptive statistics and ANOVA using IBM SPSS VER 20.0. Results: 89.5% of the dental hygienists required medical personnel of dental hygienist, the opinions on the necessity were as follows: 'role and quality improvement as oral health professionals', 'lack of legislation and application of dental hygienists duties'. There was no difference reason between dental hygienists and other personnel on duties, the reason were investigated to uncertainty of dental hygienist system, lack of dental hygienist workforce, dentists lack awareness of dental hygienist expertise. There was surveyed by the current many frequency duties in the dental clinic, assist for dental treatment, Oral health education and counselling, Preventive dental treatment. Conclusions: Legal guarantees for clinical dental hygienists work are absolutely required. Therefore, relevant government agencies and related organizations should resolve the contradiction of the legal system of medical law and medical technicians. The clinical dental hygienists should be promoted to medical personnel through the amendment of the medical law so that the duties practiced by the dental hygienist can be matched with the legal practice.

• Journal of Korean Society on Water Environment
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• v.37 no.3
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• pp.204-216
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• 2021

It is important to understand the factors influencing the temporal and spatial variability of water quality in order to establish an effective customized management strategy for contaminated aquatic ecosystems. In this study, the spatial diversity of the 5-year (2015 - 2019) average total phosphorus (TP) concentration observed in 40 Total Maximum Daily Loads unit-basins in the Nakdong River watershed was analyzed using 50 predictive variables of watershed characteristics, climate characteristics, land use characteristics, and soil characteristics. Cross-correlation analysis, a two-stage exhaustive search approach, and Bayesian inference were applied to identify predictors that best matched the time-averaged TP. The predictors that were finally identified included watershed altitude, precipitation in fall, precipitation in winter, residential area, public facilities area, paddy field, soil available phosphate, soil magnesium, soil available silicic acid, and soil potassium. Among them, it was found that the most influential factors for the spatial difference of TP were watershed altitude in watershed characteristics, public facilities area in land use characteristics, and soil available silicic acid in soil characteristics. This means that artificial factors have a great influence on the spatial variability of TP. It is expected that the proposed statistical modeling approach can be applied to the identification of major factors affecting the spatial variability of the temporal average state of various water quality parameters.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.240-252
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• 2016

The purposes of this paper examines the extant to which congruence in leader and follower rating of LMX quality is related to organizational commitment, and perceptions of organizational politics(POPs). A conceptual model is introduced that identifies four combinations of leader and follower LMX ratings of Cogliser et al.(2009): balanced/low LMX(low leader and follower LMX), balanced/high LMX(high leader and follower LMX), follower overestimation(low leader LMX/high follower LMX), follower underestimation(high leader LMX/low follower LMX). The summary of results based on a sample of 236 matched pairs of leaders and followers in KOREA is as follows: First, balanced/high LMX and follower overestimation were associated with relatively high levels of affective organizational commitment, and perceptions of organizational politics. However, follower underestimation and balanced/low LMX was related to low levels of follower outcomes. In particular, follower underestimation and balanced/low LMX were significantly different from balanced/high LMX and follower overestimation. Second, perceptions of organizational politics was negatively related to affective organizational commitment in the four LMX relationship types. Especially, the negative relationship between POPs and organizational commitment was stronger for people who are low as compared with high in LMX quality. Theoretical and practical implications of our findings as well as directions for future research are provided.

• Journal of Korea Water Resources Association
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• v.48 no.5
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• pp.367-377
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• 2015

ADCPs have been highlighted so far for measuring steramflow discharge in terms of their high-order of accuracy, relatively low cost and less field operators driven by their easy in-situ operation. While ADCPs become increasingly dominant in hydrometric area, their actual measurement accuracy for velocity and bathymetry measurement has not been sufficiently validated due to the lack of reliable bench-mark data, and subsequently there are still many uncertain aspects for using ADCPs in the field. This research aimed at analyzing inter-comparison results between ADCP measurements with respect to the detailed ADV measurement in a specified field environment. Overall, 184 ADV points were collected for densely designed grids for the given cross-section that has 6 m of width, 1 m of depth, and 0.7 m/s of averaged mean flow velocity. Concurrently, ADCP fixed-points measurements were conducted for each 0.2m and 0.02m of horizontal and vertical spacing respectively. The inter-comparison results indicated that ADCP matched ADV velocity very accurately for 0.4~0.8 of relative depth (y/h), but noticeable deviation occurred between them in near surface and bottom region. For evaluating the capacity of measuring bathymetry of ADCPs, bottom tracking bathymetry based on oblique beams showed better performance than vertical beam approach, and similar results were shown for fixed and moving-boat method as well. Error analysis for velocity and bathymetry measurements of ADCP can be potentially able to be utilized for the more detailed uncertainty analysis of the ADCP discharge measurement.

• Journal of Korea Water Resources Association
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• v.46 no.6
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• pp.569-583
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• 2013

This study is to evaluate the future climate change impact on hydrological components in the Seolmacheon ($8.54km^2$) mixed forest catchment located in the northwest of South Korea using SWAT (Soil and Water Assessment Tool) model. To reduce the uncertainty, the model was spatially calibrated (2007~2008) and validated (2009~2010) using daily observed streamflow, evapotranspiration, and soil moisture data. Hydrological predicted values matched well with the observed values by showing coefficient of determination ($R^2$) from 0.74 to 0.91 for streamflow, from 0.56 to 0.71 for evapotranspiration, and from 0.45 to 0.71 for soil moisture. The HadGEM3-RA future weather data of Representative Concentration pathway (RCP) 4.5 and 8.5 scenarios of the IPCC (Intergovernmental Panel on Climate Change) AR5 (Assessment Report 5) were adopted for future assessment after bias correction of ground measured data. The future changes in annual temperature and precipitation showed an upward tendency from $0.9^{\circ}C$ to $4.2^{\circ}C$ and from 7.9% to 20.4% respectively. The future streamflow showed an increase from 0.6% to 15.7%, but runoff ratio showed a decrease from 3.8% to 5.4%. The future predicted evapotranspiration about precipitation increased from 4.1% to 6.8%, and the future soil moisture decreased from 4.3% to 5.5%.