• Structural Engineering and Mechanics
• /
• 제37권5호
• /
• pp.561-573
• /
• 2011

For efficient calculation of natural modes of structures, a numerical scheme which accelerates convergence of the subspace iteration method by employing accelerated starting Lanczos vectors was proposed in 2005. This paper is an extension of the study. The previous study simply showed feasibility of the proposed method by analyzing structures with smaller degrees of freedom. While, the present study verifies efficiency of the proposed method more rigorously by comparing closeness of conventional and accelerated starting vectors to genuine eigenvectors. This study also analyzes an example structure with larger degrees of freedom and more complex constraints in order to investigate applicability of the proposed method.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권8호
• /
• pp.4090-4102
• /
• 2018

After emerging online communications, text mining and sentiment analysis has been frequently applied into analyzing electronic word-of-mouth. This study aims to develop a domain-specific lexicon of sentiment analysis to predict box office success in Korea film market and validate the feasibility of the lexicon. Natural language processing, a machine learning algorithm, and a lexicon-based sentiment classification method are employed. To create a movie domain sentiment lexicon, 233,631 reviews of 147 movies with popularity ratings is collected by a XML crawling package in R program. We accomplished 81.69% accuracy in sentiment classification by the Korean sentiment dictionary including 706 negative words and 617 positive words. The result showed a stronger positive relationship with box office success and consumers' sentiment as well as a significant positive effect in the linear regression for the predicting model. In addition, it reveals emotion in the user-generated content can be a more accurate clue to predict business success.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2007년 가을학술발표회
• /
• pp.431-439
• /
• 2007

Data logger is generally needed for gathering field information automatically(or manually), using various sensors. However it, currently used in the county, is produced and developed by overseas. It is difficult to upgrade related program due to developed system and limited user in terms of environment it is used. On the other hand, several companies developed and sold unique data logger based their technique expertise in the country. But enhancement and practical use of related technology has much difficulties because feasibility, marketability and demand for technique are uncertain. In this study, it is the main purpose to offer basic information to select equipment suitable for field characteristic through analysis and comparison with features about method of information collection, operating program and process technique data logger which is used primarily in geotechnical engineering in both domestic and international.

• Geomechanics and Engineering
• /
• 제16권5호
• /
• pp.513-525
• /
• 2018

Slope stability of sensitive clayey soils is particularly important when subjected to strength loss and deformation. Except for progressive failure, for most sensitive and insensitive slopes, it is important to review the feasibility of conventional analysis methods based on peak strength since peak strength governs slope stability before yielding. In this study, as a part of efforts to understand the behavior of sensitive clay slopes, a total of 12 centrifuge tests were performed for artificially sensitive and insensitive clay slopes using San Francisco Bay Mud (PI = 50) and Yolo Loam (PI = 10). In terms of slope stability, the results were analyzed using the updated instability factor ($N_I$). $N_I$ using equivalent unit weight to cause a failure is in reasonable agreement shown in the Taylor's chart ($N_I$ ~ 5.5). In terms of dynamic deformation, it is shown that two-way sliding is a more accurate approach than conventional one-way sliding. Two-way sliding may relate to diffused shear surfaces. The outcome of this study is contributable to analyzing stability and deformation of steep sensitive clay slopes.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
• /
• pp.19-20
• /
• 2012

According to develop urban area, the depth and floor area of basement tend to become deeper and larger. Excavation work for basement floor work is very important because its cost take 20% of total construction cost. Therefore, many studies of developing retaining wall system have performed for feasibility and safety in deep excavation work. In this study, new supporting system used high-strength pipe for retaining wall is introduced to reduce the construction cost and improve the safety and constructability by analyzing case study.

• 농업과학연구
• /
• 제37권1호
• /
• pp.105-112
• /
• 2010

The objective of this study is to develop a standardized model for analyzing water balances in large scaled water basin by considering agricultural water districts, and to evaluate the hydrological feasibility of applying this model to several water districts such as Nonbul, Geumbok, Daejeon 1, Daejeon 2, and Cheonggang in Geum river basin. Ten types of stream network were considered in developed model. Using this model, streamflows were simulated by major stations and water balances were analyzed by water districts. Simulated streamflows and measured streamflows were compared at check stations such as Gapcheon and Bugang stations in which Nash and Schcliffe's model efficiencies were 0.633, 0.902, respectively. This results showed its applicabilities to national water resources plan, rural water development plan, and total maximum daily load plan in Korea.

• 한국과학교육학회지
• /
• 제33권4호
• /
• pp.840-862
• /
• 2013

이 연구는 과학 수업에서 논증 담화를 분석하기 위한 대안적 방법들을 제안했던 최근의 주요 선행 연구들을 논증활동의 협력적 구성과 인식적 실행의 측면에서 방법론적으로 고찰하였다. 또한, 선행 연구들에서 사용된 논증 담화 분석 방법의 성과와 제한점을 바탕으로 새로운 논증 담화 분석 방법을 제안하고, 이 논증 담화 분석법을 실제 과학 수업의 논증 담화에 적용하여 그것의 활용 가능성을 알아보았다. 연구를 위해 과학 수업의 논증 담화에 대한 선행 연구 중 Toulmin의 논증 틀을 논증 담화 분석에 적용한 연구, 논증의 구조, 내용, 및 정당화 과정을 종합적으로 조사하는 논증 담화 분석 방법을 모색한 연구, 그리고 논증 담화의 증거에 기반한 추론 과정을 강조한 연구들을 선정하였다. 또한, 담화 레지스터와 증거-설명의 연속선에 기반한 대안적 논증 담화 분석 방법으로서 DREEC을 고안하였고, DREEC을 수업 담화 사례에 적용하였다. 연구 결과, 선행 연구들에 사용된 논증 담화 분석 방법들은 주로 Toulmin의 논증 틀에서 제시한 논증 구성 요소의 유무에 근거하여 논증의 구조를 파악하였다. 이러한 접근은 논증 담화의 정량적 분석 및 비교는 가능한 반면, 논증의 정당화 과정 및 인식적 실행의 전개 과정에 기반한 논증의 질적 기술 및 비교가 어려웠고, 논증 담화 참여자들의 협력적 논증 구성 과정을 구체적으로 보여주지 못하는 한계가 있었다. 반면에 DREEC은 주제부/설명부 간에 형성된 연결 관계와 자료, 증거, 패턴, 및 설명에 이르는 연결 관계를 통해 논증의 협력적 구성과, 인식적 실행의 흐름에 기반하여 논증의 정당화 과정을 분석할 수 있었다.

• 대한교통학회지
• /
• 제27권1호
• /
• pp.117-127
• /
• 2009

본 논문에서는 우리나라의 도로교통사업의 타당성 평가시 활용되는 국가교통DB 기종점 자료를 이용하여, 통행량 변화에 따른 추정 링크 교통량의 불확실성을 분석하였다. 분석 결과, 평균적으로 기종점 통행량의 확률변동으로 변화될 수 있는 전체 국가교통DB 네트워크의 교통량 불확실성 정도는 15.4%로, 혼잡한 구간의 교통량에 대한 불확실성이 그렇지 않은 구간의 불확실성보다 매우 큰 것으로 나타났다. 특히, 본 논문에서는 교통량 추정치에 대한 분산추정치를 계산하고 이를 토대로, 주어진 신뢰수준에서 구간추정 치를 제시하여 교통투자를 결정하는 의사결정가나 분석가들에게 다양한 정보를 제공할 수 있는 기틀을 마련하였으며 도로부문 투자에 대한 불확실성을 정량적으로 평가할 수 있는 토대를 마련하였다.

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.242-249
• /
• 2009

High-rise construction sites, especially those situated in spatially constrained urban areas, have difficulties in timely delivery of materials. Modern techniques such as Just-in-time delivery, and use of information technology such as Project Management Information System (PMIS), are targeted to improve the efficiency of the logistics. Such IT-driven management techniques can be further benefited from state-of-the-art devices such as Radio Frequency Identification (RFID) tags and Ubiquitous Sensor Networks (USN), which has resulted in notable achievements in automated logistics management at the construction sites. Based on those achievements, this research develops USN hardware toolkits for construction lifts, which aims to be automated the vertical material delivery by sensing the material information and routing it automatically to the right place. The gathered information from the sensors can also be used for monitoring the overall status. The developed system will be tested in the actual high-rise construction sites to assess the system's feasibility. The proposed system is being implemented using Zigbee communication modules and RFID sensor networks which will communicate with the intelligent palette system (previously developed by the authors). To support the system, a lift-mountable intelligent toolkit is under development. Its feasibility test will be conducted by applying the implemented system to a test bed and then analyzing efficiency of the system and the toolkit. The collected test data will be provided as a basis of autonomous vertical transport equipment development. From this research, efficient management of the material lift is expected with increased accuracy, as well as better management of overall construction schedule benefited from the system. Further research will be expected to develop a smart construction lift, which will eliminate the need for human supervision, thus enabling a real 'autonomous' operation of the system.

• 인터넷정보학회논문지
• /
• 제21권2호
• /
• pp.19-26
• /
• 2020

This paper analyses the feasibility of using implantable antennas to detect and monitor tumors. We analyze this setting according to the wireless propagation loss and signal fading produced by human bodies and their environment in an indoor scenario. The study is based on the ITU-R propagation recommendations and prediction models for the planning of indoor radio communication systems and radio local area networks in the frequency range of 300 MHz to 100 GHz. We conduct primary estimations on 915 MHz and 2.4 GHz operating frequencies. The path loss presented in most short-range wireless implant devices does not take into account the human body as a channel itself, which causes additional losses to wireless designs. In this paper, we examine the propagation through the human body, including losses taken from bones, muscles, fat, and clothes, which results in a more accurate characterization and estimation of the channel. The results obtained from our simulation indicates a variation of the return loss of the spiral antenna when a tumor is located near the implant. This knowledge can be applied in medical detection, and monitoring of early tumors, by analyzing the electromagnetic field behavior of the implant. The tumor was modeled under CST Microwave Studio, using Wisconsin Diagnosis Breast Cancer Dataset. Features like the radius, texture, perimeter, area, and smoothness of the tumor are included along with their label data to determine whether the external shape has malignant or benign physiognomies. An explanation of the feasibility of the system deployment and technical recommendations to avoid interference is also described.