• Title/Summary/Keyword: Historical Data

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A Study on the Construction of Historical Profiles for Travel Speed Prediction Using UTIS (UTIS기반 구간통행속도 예측을 위한 교통이력자료 구축에 관한 연구)

  • Ki, Yong-Kul;Ahn, Gye-Hyeong;Kim, Eun-Jeong;Bae, Kwang-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.6
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    • pp.40-48
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    • 2012
  • In this paper, we suggests methods for determining optimal representative value and the optimal size of historical data for reliable travel speed prediction. To evaluate the performance of the proposed method in real world environments, we did field tests at four roadway links in Seoul on Tuesday and Sunday. According to the results of applying the methods to historical data of Central Traffic Information Center, the optimal representative value were analyzed to be average and weighted average. Second, it was analyzed that 2 months data is the optimal size of historical data used for travel speed prediction.

A Study on Developing the Acquisition Unit Cost Estimating Model of the Guided Weapon System (유도무기 획득단가 추정 모델 개발에 관한 연구)

  • Kim, Yonghyun;Lee, Yongbok;Jung, Wonil;Kim, Dongkyu;Kang, Sungjin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.5
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    • pp.565-576
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    • 2012
  • Cost estimates are necessary for government acquisition program to support decisions about funding, to develop annual budget requests and to validate resource requirements at key decision points. Many researches have been done about cost estimating technique recently. Parametric cost estimating models based on CERs(Cost Estimating Relationships) have been mainly used using regression method with historical data. However, there are many restrictions in developing Korean version CERs because the number of data points are too small. Specially, data collection and data management system are unstable in Korean defense environment, when developing CERs. In this research, we analyzed the historical data, and found some cost drivers in guided weapon system area. We developed the Acquisition Unit Cost CER using the regression to remove multicollinearity in the historical data. So we could overcome the restriction of the insufficient sample number. This research as a first attempt is meaningful in terms of obtaining our own Acquisition Unit Cost CER using historical cost and physical characteristic in Korean development environment.

Climatic Records of Japan : A Historical Overview

  • Yoshino, Masatoshi
    • Atmosphere
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    • v.13 no.2
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    • pp.29-39
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    • 2003
  • Proxy data in the historical period in Japan since the 9th century has been first described and their analyzed fluctuation series were shown. Secondly, the climatic records before and after the Meiji restoration in 1868 were mentioned. Thirdly, available date sets of historical climatic records in Japan are listed. Lastly, published records and tables for Japan during the recent years were overviewed. Some discussion on the climatic records and tables is given as concluding remarks.

Analysis of Time Data in Japanese Astronomical Almanacs of 1885-1943

  • Lee, Ki-Won;Choi, Go-Eun;Ahn, Young-Sook
    • Bulletin of the Korean Space Science Society
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    • 2011.04a
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    • pp.19.4-20
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    • 2011
  • In this paper, we analyze time data (i.e., new moon time, sunrise and sunset times, twenty-four seasonal subdivision times, and so forth) in the Japanese astronomical almanacs between 1885 and 1943. During this period, two types of astronomical almanacs were published in Japan; Honreki (本曆; Formal Almanac) and its simplified version, Ryakuhonreki (略本曆). We use mainly the latter almanac for analyzing the time data. It is also known that Japan introduced the Gregorian calendar in 1873, adopted the standard meridian of $135^{\circ}E$ in 1888, and used Tokyo Observatory (東京天文臺; $139^{\circ}$ 44' 30" E and $35^{\circ}$ 39' 15" N) as the reference position of time data since 1891. We verify those facts and investigate the accuracy of time data in Japanese almanacs by comparing the data with the results of modern calculations. In this study, we present our findings.

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Spatio-Temporal Query Processing Over Sensor Networks: Challenges, State Of The Art And Future Directions

  • Jabeen, Farhana;Nawaz, Sarfraz;Tanveer, Sadaf;Iqbal, Majid
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.7
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    • pp.1756-1776
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    • 2012
  • Wireless sensor networks (WSNs) are likely to be more prevalent as their cost-effectiveness improves. The spectrum of applications for WSNs spans multiple domains. In environmental sciences, in particular, they are on the way to become an essential technology for monitoring the natural environment and the dynamic behavior of transient physical phenomena over space. Existing sensor network query processors (SNQPs) have also demonstrated that in-network processing is an effective and efficient means of interaction with WSNs for performing queries over live data. Inspired by these findings, this paper investigates the question as to whether spatio-temporal and historical analysis can be carried over WSNs using distributed query-processing techniques. The emphasis of this work is on the spatial, temporal and historical aspects of sensed data, which are not adequately addressed in existing SNQPs. This paper surveys the novel approaches of storing the data and execution of spatio-temporal and historical queries. We introduce the challenges and opportunities of research in the field of in-network storage and in-network spatio-temporal query processing as well as illustrate the current status of research in this field. We also present new areas where the spatio-temporal and historical query processing can be of significant importance.

Developing an R&D CER Using Historical Defense Weapon System Data in Korea (한국 무기체계 개발 실적을 고려한 연구개발 비용추정관계식 개발)

  • Eo, Won-Jae;Lee, Yong-Bok;Kang, Sung-Jin
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.33 no.3
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    • pp.55-62
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    • 2010
  • Currently, cost estimation is very important to the government acquisition programs to support decisions about funding and to evaluate resource requirement as key decision points. Parametric cost estimating models have been used extensively to obtain appropriate cost estimates in early acquisition phase. However, they have many restrictions to ensure the cost estimating result in Korean defense environment because they are developed in the U.S.A. environment. In order to obtain a good R&D cost estimate, developing our own CERs (Cost Estimation Relationships) using historical R&D data is essential. Nevertheless, there has been little research to develop our own CERs. In this research, we established a CER development process and found some cost drivers in the historical movement weapon system R&D data. The R&D CER is developed using the PCR(Principle Component Regression) method to remove multicollinearity among data and to overcome the restriction of the insufficient number of sample. At least, this research is meaningful as a first attempt in terms of defining the CER development process and obtaining our own R&D CER based on the historical data in Korean weapon system R&D environment.

A Proposal for Use in Research Methodology of Traditional Medicine in East Asia - Historical Evidence-Based Medicine - (전통한의학 연구방법론의 현대화에 대한 소고(小考) - 역사적 근거중심의학에 대한 제언 -)

  • Eom, Seok-Ki;Kim, Se-Hyun;Choi, Won-Cheol
    • Journal of Korean Medical classics
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    • v.23 no.2
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    • pp.89-105
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    • 2010
  • Research methodology on Traditional Medicine in East Asia refers to logical thinking system, empirical positivism system and methodology of developing these knowledge systems. Logical thinking system of abstract concepts such as analogy or abduction and positivism system of reasonable explanation such as the five elements and their characteristic theory have been used in various ways empirically or in the form of humanities and knowledge system was developed through parallel structure of empirical positivism and exegetical studies. After the 16th century, evidence was required along with the tradition of putting emphasis on rationality, logicality and empirical positivism and characteristics of medical humanities can be found in emphasizing on medical ethics. Data that can be considered as structural review paper or meta analysis from original data of research on Traditional East Asian Medicine should be evaluated as historical evidence which is equivalent to specialist opinion, descriptive disease research, single case report or case series. Historical evidence based medicine is a research method using Historical evidence to selectively support data that are faithful to traditional theory with higher possibility to be used in future traditional east Asian medicine that links between traditional knowledge and scientific research methodology. Moreover, historical evidence based medicine tries to re-evaluate the value of traditional knowledge and ultimately, guides the direction of development of traditional medicine through scientific rationality based on history and culture.

A Study on the Construction Cost Estimating System based on Historical Data in Apartment Housing (실적공사비 산정시스템에 관한 연구 - 공동주택을 중심으로 -)

  • Jun, Seok-Han;Choi, In-Sung
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.1 s.15
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    • pp.111-121
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    • 2005
  • This study purposed to derive a model to estimate appropriate construction costs for the application of the estimation system based on historical construction data. For this purpose, it analyzed data ($1999\sim2004$) on the construction costs of reinforced concrete apartments (Long-Lamina-type apartments), which have been highly standardized and have a lot of relevant objective data using statistical analysis techniques and developed an estimation model.

A Study on the Presumption for Attenuation Relation by MT. O-dae earthquake data in Korea (오대산 지진자료에 의한 거리감쇠식 추정에 관한 연구)

  • Kwon, Ki-Hyuk;Hwang, Wan-Seon;Yu, Hye-Ran
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.33-36
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    • 2008
  • In Korean Building Code 2005(KBC-2005), the Seismic Zone Factor is regulated by separating the seismic zone into two part. This seismic zone factor is not matched to regional seismic characteristics of our country because the factor is based on International Building Code 2000 (IBC-2000) of USA. This study inquiry for having a sufficient grasp of the seismic characteristics of south Korea region and appling for the seismic cope plan. We have collected and analyzed earthquake record happened in domestic region. There are two kinds of earthquake record. One is Historical earthquake data, another is Instrumental earthquake data. I used Instrumental earthquake record data which reliance is higher than historical earthquake data for proposing attenuation formulas by analyzing a correlation the epicenter and the distance.

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Historical Controls, Data Banks, and Randomized Trials in Clinical Research: A Review

  • Fleming Thomas R.
    • 대한예방의학회:학술대회논문집
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    • 1994.02b
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    • pp.265-269
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    • 1994
  • A brief review is presented of the strengths and weaknesses of historical controls, data banks, and randomized trials in the evaluation of clinical treatment. Use of pre randomized versus postrandomized informed consent is discussed. Recommendations are made for the development of an appropriate clinical research strategy.

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