• Journal of Ecology and Environment
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• v.45 no.4
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• pp.313-327
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• 2021

Background: Citizen science is becoming a mainstream approach of baseline data collection to monitor biodiversity and climate change. Dragonflies (Odonata) have been ranked as the highest priority group in biodiversity monitoring for global warming. Ischnura senegalensis Rambur has been designated a biological indicator of climate change and is being monitored by the citizen science project "Korean Biodiversity Observation Network." This study has been performed to understand changes in the distribution range of I. senegalensis in response to climate change using citizen science data in South Korea. Results: We constructed a dataset of 397 distribution records for I. senegalensis, ranging from 1980 to 2020. The number of records sharply increased over time and space, and in particular, citizen science monitoring data accounted for the greatest proportion (58.7%) and covered the widest geographical range. This species was only distributed in the southern provinces until 2010 but was recorded in the higher latitudes such as Gangwon-do, Incheon, Seoul, and Gyeonggi-do (max. Paju-si, 37.70° latitude) by 2020. A species distribution model showed that the annual mean temperature (Bio1; 63.2%) and the maximum temperature of the warmest month (Bio5; 16.7%) were the most critical factors influencing its distribution. Future climate change scenarios have predicted an increase in suitable habitats for this species. Conclusions: This study is the first to show the northward expansion in the distribution range of I. senegalensis in response to climate warming in South Korea over the past 40 years. In particular, citizen science was crucial in supplying critical baseline data to detect the distribution change toward higher latitudes. Our results provide new insights on the value of citizen science as a tool for detecting the impact of climate change on ecosystems in South Korea.

• Journal of applied mathematics & informatics
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• v.39 no.5_6
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• pp.785-804
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• 2021

The proposal of new families has been worked out by many authors over recent years. Many ways to generate new families have been developed as the methods of addition, linear combination, composition and, one of the newer, the T-X family of distributions. Using this latter method, Korkmaz et al. (2018) proposed a new class called Weibull Marshall-Olkin-G (WMO-G) family. In the present work, we propose a new distribution, based on the WMO-G family, using the Lomax distribution as baseline, called Weibull Marshall-Olkin Lomax (WMOL) distribution. The hazard rate function of this distribution can be increasing, decreasing, bathtub-shaped, decreasing-increasing-decreasing and unimodal. Some properties of the proposed model are developed. Besides that, we consider method of maximum likelihood for estimating the unknown parameters of the WMOL distribution. We provide a simulation study in order to verify the asymptotic properties of the maximum likelihood estimates. The applicability of the new distribution to modeling real life data is proved by two real data sets.

• Journal of Distribution Science
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• v.20 no.4
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• pp.21-31
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• 2022

Purpose: The study focuses on the distribution of brand love on customers' behavioral intention at five-star hotels in Vietnam. Furthermore, the study also assesses the role of mediating variables and moderating variable involved in the research model. Research design, data and methodology This research surveys 458 customers using the services of five-star hotels in Vietnam through questionnaires on online platforms. Data cleaning and data analysis using SPSS 25.0 software combined with Smart-PLS 3.0 software were used in the research to evaluate the measurement model and structural model. Results: From the results of the structural model evaluation, it shows the positive distribution of brand love on customers' behavioral intentions towards five-star hotels in Vietnam. The mediating roles of brand engagement, brand equity, customer motivation, and the participation of the moderating variable, customer expectations, are determined by this research model. Conclusions: Based on the study results, the distribution of brand love positively affects customers' behavioral intention at five-star hotels in Vietnam, giving recommendations that have a positive impact on customer behavioral intention. In addition, the study shows the role of mediating variables as well as exploring the moderator's (customer expectations) in the distribution of relationships between customer motivation and customer behavioral intention.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.2
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• pp.243-247
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• 2016

Driving Event Data such as the rapid acceleration, the rapid deceleration, the sudden braking, and the sudden departure, and over speeding provide important information to predict or analyze the driving habits and accident risk of a driver. Most of the data that represent the driver's driving habits generally fit to the parametric distribution, whereas extreme parts of the data to estimate the accident risk of a driver may not. This paper presents an empirical distribution that is divided into two regions, one is from the normal distribution, and the other is from the general pareto distribution for the driving habits of a driver.

• Journal of Ocean Engineering and Technology
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• v.34 no.1
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• pp.26-36
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• 2020

An extreme value analysis of metocean data which include wave, wind, and current data is a prerequisite for the operation and survival of offshore structures. The purpose of this study was to provide information about the return wave, wind, and current values for the Barents Sea using extreme value analysis. Hindcast datasets of the Global Reanalysis of Ocean Waves 2012 (GROW2012) for a waves, winds and currents were obtained from the Oceanweather Inc. The Gumbel distribution, 2 and 3 parameters Weibull distributions and log-normal distribution were used for the extreme value analysis. The least square method was used to estimate the parameters for the extreme value distribution. The return values, including the significant wave height, spectral peak wave period, wind speed and current speed at surface, were calculated and it will be utilized to design offshore structures to be operated in the Barents Sea.

• Progress in Medical Physics
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• v.28 no.2
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• pp.49-53
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• 2017

The energy distribution was calculated for an electron beam from an electron linear accelerator developed for medical applications using computational methods. The depth dose data for monoenergetic electrons from 0.1 MeV to 8.0 MeV were calculated by the DOSXYZ/nrc code. The calculated data were used to generate the energy distribution from the measured depth dose data by numerical iterations. The measured data in a previous work and an in-house computer program were used for the generation of energy distribution. As results, the mean energy and most probable energy of the energy distribution were 5.7 MeV and 6.2 MeV, respectively. These two values agreed with those determined by the IAEA dosimetry protocol using the measured depth dose.

• Nuclear Engineering and Technology
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• v.33 no.4
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• pp.441-456
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• 2001

ABB-CE＇s regionalization methodology for the core inlet flow distribution map is reviewed. This methodology merges the test data of fuel assembly locations which are either in symmetry or strongly correlated with others. It increases the number of available test data for each regional flow factor It makes up effectively for the deficiency due to limited number of test data. It also contributes to making the core inlet flow distribution smoother not only locally but also over the entire core, and to relieving the impacts of test errors that may happen due to some do- calibrated local pressure measurement taps. As a result, the core inlet How distribution data becomes more statistically useful and thus the conservatism involved in handling the core inlet flow factors for the thermal margin analysis is expected to be reduced. Meanwhile, the regionalized map may lose the unique local characteristics in core inlet flow distribution too much. By an alternative approach introduced in the present work, it is shown that such a disadvantage can be mitigated somewhat if the engineering judgement is made more

• Journal of Distribution Science
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• v.20 no.11
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• pp.19-31
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• 2022

Purpose: This research aims to analyze the educational potential and students' satisfaction with the quality of education services distribution in Kazakhstani universities. The conceptual review shows that very few studies on regional development have been able to determine the level of satisfaction with the quality of educational services depending on the university's location. Research design, data, and methodology: The research methodology is divided into two approaches descriptive analysis and qualitative data analysis. The current educational situation and the distribution of educational services in the largest Kazakh universities were studied based on the proposed approaches' use. Statistical data are taken for indicators of educational potential for 2010-2020 from the Bureau of National Statistics. The primary data were collected based on a survey for 2021-2022 in five regions of Kazakhstan. Results: The results showed that there is a gender gap between men and women and regional disparities between the regions of Kazakhstan in the coverage of higher education. The results of the sociological survey revealed that the quality of educational services depends on the territorial location of the university. Conclusions: Based on the results of the assessment of educational potential and educational services, policy recommendations and further research in this area were proposed.

• KIPS Transactions on Software and Data Engineering
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• v.8 no.4
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• pp.137-144
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• 2019

Testing maturity is critical to the system under development with lack of experience and skills in the acquisition of the weapon systems. Defects have a huge impact on important system operations. Sharing real-time information will lead to rapid command and mission capability in submarine. DDS(Data Distribution System) is a very important information sharing system and interface between various manufacturers or data formats. In this paper, we analyze data distribution characteristics of distributed data system to group data-specific systems and proposes a test case-generation method using path search of postorder and preorder which is a tree traversal in path testing method. The proposed method reduces 73.7.% testing resource compare to existing methods.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.1
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• pp.141-154
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• 2022

In the data economy era, various policies are being implemented to create an active data distribution environment. In South Korea, the formation of a big data distribution platform and data trading began with the launch of the Financial Data Exchange under public data governance. In the case of major advanced countries in the data field, they have built a data distribution environment based on the data broker industry for decades and have strengthened national data competitiveness through added values generated from the industry. However, behind the active data distribution through data brokers, there are numerous information security issues, which have resulted in various privacy issues and national security threats. These problems can occur sufficiently in the process of domestic financial data exchange. In our study, we analyzed various information security issues of data trading caused by data brokers and derived information security requirements to be considered when trading data. We verified whether information security requirements are well reflected in the information security policy for each transaction stage of the domestic financial data exchange. Based on the verification, measurements to strengthen information security for financial data exchange are presented in our paper.