• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제16권1호
• /
• pp.231-244
• /
• 2022

With the improvement of people's living standards and the development of tourism, tourists have greater freedom in choosing destinations. Therefore, as an indicator of satisfaction with scenic spots, tourist comments are becoming increasingly prominent. This paper aims to compare and analyze the landscape image of the Five Great Mountains in China and provide specific strategies for its development. The online reviews of tourists on the Online Travel Agency (OTA) website about the Five Great Mountains from 2015 to 2018 are collected as research samples. The text analysis method and R language are used to analyze the content of the tourist reviews, while the high-frequency words in the word cloud are used for visual display. In addition, the entropy weight method is used to determine the index weight and tourist satisfaction is evaluated to understand the weaknesses of those scenic spots. The results of the study show that firstly, the tourist satisfaction with the Five Great Mountains is basically consistent with its popularity. Secondly, through weight analysis, tourists pay special attention to the landscape features and environmental health of the scenic area, so that relevant departments should focus on building the landscape characteristics and improving the environmental health of the scenic area. At the same time, the accommodation and service management of the scenic spot cannot be ignored. Finally, according to the analysis results, suggestions are made on how to improve the tourist satisfaction with the Five Great Mountains.

• 대한기계학회논문집
• /
• 제19권2호
• /
• pp.427-432
• /
• 1995

Surface heat treatment using a laser beam or an electron beam is studied through numerical analyses and experiments. For the surface heat treatment process, a theoretical model is developed to predict the effects of laser beam power, travel speed and properties of a workpiece on the depth and width of the heat affected zone(HAZ). The shape of HAZ and the hardness of heat-treated surface are experimentally obtained using an electron beam. Three materials(SS41, S45C and S55C) are selected as workpiece materials. The hardness of HAZ is increased up to 3 times for materials of a low carbon content. The results of the numerical analysis are compared with those of experiments. The comparison shows that the numerical model predicts larger depths and widths.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 1998년도 특별강연 및 춘계학술발표 개요집
• /
• pp.150-154
• /
• 1998

The purpose of this paper is to investigate optimum welding conditions of STS 304 thin sheet by GTA welding and control 6 $\delta$--fenite which is harmful in mechanical processing, corrosion problem and can be formed brittle a phase in using long term at high temperature. One series of automatic welds was made using argon plus 10, 20, 30 % nitrogen to ensure a fully austenite deposit. Results obtained were summarized as follows: 1) 6 $\sigma$ferrite content in the weld metals is influenced largely by the nitrogen content. 2) Additions of nitrogen to the shielding gas can significantly reduce the amount of retained delta ferrite and result in an increase in hot cracking. 3) Bead width was increased when Ar + $N_2$ shielding gas was used and travel speed was increased. 4) Ar+$N_2$ shielding gas made weld metal ductile and reduce 6 -$\delta$-ferrite.

• 영어어문교육
• /
• 제8권2호
• /
• pp.197-218
• /
• 2003

The purpose of this study is to help the students in middle school improve their English listening comprehension by presenting effective teaching and learning techniques using animation. A good animation provides a self-contained world with language expressed in a virtual context. A few animation such as "Mulan", "The Emperor's New Clothes", and "Gulliver's Travel" are presented. The materials are primarily for English listening comprehension, enhance awareness of American culture and life-styles, and to encourage students' active role in learning English. It is suggested that their use with content-based instruction, where animation provides relevant schema background, makes language relevant and comprehensible. Practical aspects of classroom instruction are discussed, focusing on the adaption of pre-viewing, while-viewing, and post-viewing activities to the selected animation. It is concluded that careful animation selection, purposeful lesson planning, and the integration of pre-viewing, while-viewing, and post-viewing activities into the content-based lesson encourage natural language skills, especially the listening comprehension and students' interest in English.

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.754-757
• /
• 2009

The current concrete maturity method implemented with temperature sensors requires an extensive wiring, which is not often acceptable on construction site due to harsh working environment. Radio Frequency Identification (RFID) technology appears to provide a solution for the wiring issue because of its ability of sending data wirelessly. An RFID tag integrated with a temperature sensor and placed within fresh concrete may be able to read temperatures of concrete and transmit them to an RFID reader wirelessly in real-time. However the previous research illustrated that the RFID signal gets dispersed in liquid medium. One may speculate then whether RFID signals travel through fresh concrete with high water content. Would the tag's burying depth within fresh concrete affect its readability? The paper presents the preliminary results of our on-going investigation on the readability of RFID tags in concrete against water content and burying depth of tags.

• ETRI Journal
• /
• 제40권1호
• /
• pp.72-88
• /
• 2018

In the fifth generation (5G) era, the radio internet protocol capacity is expected to reach 20 Gb/s per sector, and ultralarge content traffic will travel across a faster wireless/wireline access network and packet core network. Moreover, the massive and mission-critical Internet of Things is the main differentiator of 5G services. These types of real-time and large-bandwidth-consuming services require a radio latency of less than 1 ms and an end-to-end latency of less than a few milliseconds. By distributing 5G core nodes closer to cell sites, the backhaul traffic volume and latency can be significantly reduced by having mobile devices download content immediately from a closer content server. In this paper, we propose a novel solution based on software-defined network and network function virtualization technologies in order to achieve agile management of 5G core network functionalities with a proof-of-concept implementation targeted for the PyeongChang Winter Olympics and describe the results of interoperability testing experiences between two core networks.

• 문화기술의 융합
• /
• 제9권3호
• /
• pp.167-181
• /
• 2023

본 연구는 코로나 19 발생 후 여행 제재가 완화된 현재의 관광행태 변화를 분석하기 위해 소셜네트워크 분석프로그램인 TEXTOM을 활용하였다. 네이버, 구글, 다음이 제공하는 블로그, 카페, 뉴스 등을 대상으로 '국내여행', '해외여행' 키워드에 대한 데이터를 수집하였다. 사회적 거리두기가 해제된 2022년 4월~12월로 수집 기간을 정하였고, 코로나19 발생 이전인 2019년과 코로나19의 영향이 가장 심각했던 2020년은 각각 1년으로 하여 2022년과 비교 분석하였다. 텍스트 마이닝을 통하여 각각 총 80개의 핵심어를 추출하고 NetDraw를 사용하여 중심성분석을 하였다. 마지막으로 CONCOR분석을 통하여 상관관계가 있는 핵심어들을 4개로 군집화하였다. 연구결과, 2022년도의 관광행태는 코로나 발생 이전으로의 관광 회복, 각자가 선호하는 테마를 중심으로 여행의 세분화, 나라별 코로나 완화정책을 우선적으로 검색해 본 후 관광지를 선택하는 관광행태를 보인다. 코로나19 이후에 새롭게 도래하는 관광생태계에 대한 관광마케팅 전략과 관광상품 개발을 위한 기초자료를 제공할 것으로 기대한다.

• 지질공학
• /
• 제15권4호
• /
• pp.487-494
• /
• 2005

흙 절개지 사면붕괴 원인은 대부분 강우에 의해 체적함수비의 증가에 따라 발생되기 때문에 체적함수비 변화를 측정할 수 있는 새로운 측정기 술이 요구된다. 본 연구에서는 체적함수비 변화를 정량적으로 측정하기 위하여 유전율 측정시스템인 FDR과 ADR 측정프로브를 사용하여 실내 토조시험을 수행하였다. 총 2단계 에 걸쳐 시간당 7.5mm/hour의 인공강우 조건하에서 압밀 화강풍화토 내 발생되는 체적 함수비와 간극수압 변화를 측정하여 비교하였다. 측정결과, 인공강우에 의한 체적 함수비와 간극수압 변화는 거의 동일한 시점에서 함께 파악되었다.

• 한국레이저가공학회지
• /
• 제7권3호
• /
• pp.25-36
• /
• 2004

This study was performed to clarification of the formation of weld discontinuities in the dissimilar laser fusion zone. Welding parameters were beam power of 1300, 1430, 1560, and 1700 W and travel speed of 1, 1.3, and 1.7 m/min. Most cavities in the fusion zone were observed near the tip. Cavities in the fusion zone observed to be formed and grown from pores in the tip. More cavities were formed as the beam position moves to the tip side. Small cavities were decreased but large cavities were increased when the energy input increased. W content in the fusion zone was increased with heat input and as the beam position close to the tip. In the fusion zone, W content in the dendrite boundary was increased with heat input. Considering the propagation path and fracture morphology, cracks were solidification cracking, and were initiated and propagated along the dendrite boundaries. The formation of cracks might be related with the W rich ${\mu}$ phase which was formed in the grain boundaries and dendrite boundaries.

• Journal of the Korean Wood Science and Technology
• /
• 제27권1호
• /
• pp.56-63
• /
• 1999

국산 죽재를 목재산업용 원재료로 활용할 수 있는 가능성을 타진하기 위하여 대표적인 우리나라 대나무 수종인 전남 담양산 맹종죽, 분죽 및 왕대의 절삭과 건조특성 등 기계가공성을 조사, 분석하였다. 연구 결과 쪼개기저항은 공구가 2.5cm 피삭재 내부로 진입하였을 때 최대로 상승하였으며, 칼날각 15도의 쐐기형 공구를 이용하면 쪼개기저항을 최소화할 수 있는 것으로 밝혀졌다. 또한 둥근톱과 띠톱에 의한 죽재의 절삭면 품질은 목재의 경우에 비하여 비교적 양호하였다. 한편 두께 12mm 맹종죽을 함수율 60%에서 10%까지 온도 $70^{\circ}C$로 건조하는데 약 62.5 시간이 소요되었다.