• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.36.3-36.3
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• 2017

The Telescope Array (TA) experiment reported the arrival direction distribution of ultra-high-energy cosmic rays (UHECRs) with energies above $5.7{\times}10^{19}eV$ in the northern sky. A clustering of TA events, the so-called hotspot, was found; however, its nature has not yet been understood. To understand the origin of the TA hotspot, we examine the sky distributions of the TA UHECR arrival direction and filamentary structures of galaxies in the local universe. By statistical tests for anisotropy, we find a close correlation of the TA events with the filaments of galaxies connected to the Virgo cluster. We discuss our finding and its implications.

• ETRI Journal
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• v.43 no.2
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• pp.272-287
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• 2021

This article presents a multi-dimensional spatial pattern analysis of crime events in San Francisco. Our analysis includes the impact of spatial resolution on hotspot identification, temporal effects in crime spatial patterns, and relationships between various crime categories. In this work, crime prediction is viewed as a classification problem. When predictions for a particular category are made, a binary classification-based model is framed, and when all categories are considered for analysis, a multiclass model is formulated. The proposed crime-prediction model (HotBlock) utilizes spatiotemporal analysis for predicting crime in a fixed spatial region over a period of time. It is robust under variation of model parameters. HotBlock's results are compared with baseline real-world crime datasets. It is found that the proposed model outperforms the standard DeepCrime model in most cases.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.181-184
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• 2011

최근 컴퓨터 가상화 기술이 발전됨에 따라 필요한 소프트웨어를 서비스 형태로 사용하는 소프트웨어 서비스(Software as a Service SaaS)가 많은 응용분야에서 사용되고 있다. 그러나 소프트웨어 서비스를 제공하는 기존 시스템은 사용자의 증가에 서버 성능이 급속히 저하되는 문제점과 일시적인 사용자 폭증으로 생기는 핫스팟(Hotspot)에 안정적인 서비스를 제공하지 못하는 문제점을 가지고 있다. 이러한 문제점들을 해결하기 위하여 본 논문은 소프트웨어 실행을 위한 작업들이 모두 서버에서 실행되는 것이 아니라 데이터 집중적인 작업들은 서버에서 직접 실행하고 그래픽 집중적인 작업들은 네트워크 전송을 통하여 클라이언트에서 처리되는 분할 실행 방식과 개별적으로 운영되는 SaaS 서버들을 하나로 통합하는 시스템을 제안한다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.311-314
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• 2020

본 논문에서는 효율적인 웹 파노라마(panorama) 콘텐츠의 효율적인 생성을 위한 에디터를 설계하고 구현한다. 이 에디터는 360° 카메라로 촬영한 파노라마 사진을 활용하여 제작하는 웹 콘텐츠의 주요소인 파노라마 관리, 핫스폿(hotspot) 지정, 추가 및 수정 관리, 파노라마 방향 보정 등의 기능을 구현 할 수 있게 마련하여 누구나 손쉽게 웹 파노라마 콘텐츠를 제작, 관리 할 수 있게 한다. 또한, 파노라마 에디터에 대한 라이브러리와 자료구조를 마련하여 콘텐츠를 개발하고자 하는 초보자나 전문 지식을 가지고 있는 개발자에게도 생산성 향상을 기대할 수 있을 것이다.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.2
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• pp.151-158
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• 2019

Objectives of this study were to identify the hotspot for displacement of the on-line water quality sensors, in order to detect illicit discharge of untreated wastewater. A total of twenty-six water quality parameters were measured in sewer networks of the industrial complex located in Daejeon city as a test-bed site of this study. For the water qualities measured on a daily basis by 2-hour interval, the self-organizing maps(SOMs), one of the artificial neural networks(ANNs), were applied to classify the catchments to the clusters in accordance with patterns of water qualities discharged, and to determine the hotspot for priority sensor allocation in the study. The results revealed that the catchments were classified into four clusters in terms of extent of water qualities, in which the grouping were validated by the Euclidean distance and Davies-Bouldin index. Of the on-line sensors, total organic carbon(TOC) sensor, selected to be suitable for organic pollutants monitoring, would be effective to be allocated in D and a part of E catchments. Pb sensor, of heavy metals, would be suitable to be displaced in A and a part of B catchments.

• Journal of the Korea Society of Computer and Information
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• v.14 no.1
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• pp.145-151
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• 2009

There are excessively hot units of a microprocessor in today's nano-scale process technology, which are called hotspots. Hotspots' heat dissipation is not perfectly conquered by mechanical cooling techniques such as heatsink, heat spreader, and fans; Hence, an architecture-level temperature simulation of microprocessors is evident experiment so that designers can make reliable chips in high temperature environments. However, conventional thermal simulators cannot be used in temperature evaluation of real machine, since they are too slow, or too coarse-grained to estimate overall system models. This paper proposes methodology of monitoring accurate runtime temperature with Hotspot[4], and introduces its implementation. With this tool, it is available to track runtime thermal behavior of a microprocessor at architecture-level. Therefore, Dynamic Thermal Management such as Dynamic Voltage and Frequency Scaling technique can be verified in the real system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.5
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• pp.307-314
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• 2023

As supercomputing and hardware technology advances, climate prediction models are improving. The Korean Meteorological Administration adopted GloSea5 from the UK Met Office and now operates an updated GloSea6 tailored to Korean weather. Universities and research institutions use Low-GloSea6 on smaller servers, improving accessibility and research efficiency. In this paper, profiling Low-GloSea6 on smaller servers identified the tri_sor_dp_dp subroutine in the tri_sor.F90 atmospheric model as a CPU-intensive hotspot. Applying linear regression, a type of machine learning, to this function showed promise. After removing outliers, the linear regression model achieved an RMSE of 2.7665e-08 and an MAE of 1.4958e-08, outperforming Lasso and ElasticNet regression methods. This suggests the potential for machine learning in optimizing identified hotspots during Low-GloSea6 execution.

• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.392-411
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• 2008

The purpose of this paper is to develop a method for exploring hotspot patterns of house price volatility where there is a high fluctuation in price and homogeneity of direction of price volatility. These patterns are formed when the majority of householders in an area show an adaptive tendency in their decision making. This paper suggests a method that consists of two analytical parts. The first part uses spatial scan statistics to detect spatial clusters of houses with a positive range of price volatility. The second part utilizes local Moran's I to evaluate the homogeneity of direction of price volatility within each cluster. The method is applied to the areas of Gangnam-Gu, Seocho-Gu, and Songpa-Gu in Seoul from August to November of 2003; the Participatory Government of Korea designated these areas and this period as the most speculative. The results of the analysis show that the area around Gaepo-Dong was as a hotspot before the Government's anti-speculative 10.29 policy in 2003; the house prices in the same area stabilized in October, 2003 and the area was identified as a coldspot in December, 2003. This case study shows that the suggested method enables exploration of hotspot of house price volatility at micro spatial scales which had not been detected by visual analysis.

• Journal of Environmental Impact Assessment
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• v.27 no.5
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• pp.417-430
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• 2018

Identification and mangement of ecosystem service hotspots are necessary to set environmental policies that include concepts of ecosystem service. Assessment and mapping of ecosystem service hotspot referring areas with high amount of ecosystem services provide essential information to manage ecosystem services effectively. Assessment of hotspots based on regional environmental stakeholders' perception is an useful approach to identify priority areas where management practices are required. This study estimated weights on regulating ecosystem services from regional environmental stakeholders' surveys in Ansan, and then, identified regulating service hotspots with weights. The result indicated that regulating services are, in order of importance, water quality, air quality, erosion, and climate control. The north-eastern forest of Ansan was mainly revealed as an ecosystem service hotspot. Ecosystem service hotspots were spatially distributed similarly regardless of environmental stakeholders' weights. Identification of ecosystem service hotspot with environmental stakeholders' perception can be applied in decision-support tools for ecosystem service management.

• Journal of the Korean Regional Science Association
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• v.35 no.4
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• pp.61-73
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• 2019

Urban development and densification have led to the Urban Heat Island Effect, in which the temperature of urban space is higher than the surrounding areas, and the intensity is increasing with climate change. In addition, when the city's air temperature rises in summer, low-income, elderly population, and socially vulnerable people who have health problems lack the ability to cope with the elevated heat environment. Therefore, this study aimed to identify the urban heat island area of Seoul through Hotspot analysis, which is a spatial statistics technique, and explored physical environments, demographic and socioeconomic characteristics of urban heat island effect areas using logistic regression models. This study performed urban heat island hotspot analysis using the average air temperatures of the 423 administrative dongs in Seoul. Analysis results identified that the urban heat islands were concentrated in Jung-gu, Jongno-gu, Yongsan-gu, and Yeongdeungpo-gu. Logistic regression analysis results indicated that urban heat island areas of Seoul were affected by residential floor area ratio, commercial facility floor area ratio, overall floor area ratio, impervious surface ratio, and normalized difference vegetation index(NDVI). In addition, as a result of analyzing the vulnerable area of thermal environment considering the demographic and socioeconomic characteristics of the heat island area, urban heat island areas of Seoul were significantly associated with the proportion of low-income elderly living alone. The result of this study provided useful insights for urban thermal environmental design and policy development that could improve the thermal environment for the socially disadvantaged urban population.