• Title/Summary/Keyword: Difficulty value

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Copy Propagation in CTOC (CTOC에서 복사 전파)

  • Kim, Ki-Tae;Kim, Je-Min;Yoo, Won-Hee
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.1 s.45
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    • pp.1-8
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    • 2007
  • Although the Java bytecode has numerous advantages. there ate also shortcomings such as slow execution speed and difficulty in analysis. Therefore. in order for the Java class file to be effectively executed under the execution environment such as the network, it is necessary to convert it into optimized code. We implements CTOC. CTOC generated CFG using the existing bytecode then created the SSA Form for analysis and optimization. However. due to insertion or the ${\phi}$-function in the process of conversion into the SSA Form, the number of nodes increased. As a means of reducing the number of nodes, we performed copy propagation, which is an optimization method applicable to the SSA form. Copy propagation is the process of a value of a variable being topied to another variable. There are cases where conversion due to copy propagation alone does not yield significant effects. However, when variables are not used in the later optimization stages, copy propagation provides a means for eliminating the copy statement for the corresponding variable, making it an important step. This paper shows the copy propagation to obtain a more optimized code in SSA Form.

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Improvement Plan of Excavation Performance Based on Shield TBM Performance Prediction Models and Field Data (쉴드 TBM 성능예측모델과 굴진자료 분석을 통한 굴진성능 개선방안)

  • Jung, Hyuksang;Kang, Hyoungnam;Choi, Jungmyung;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.2
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    • pp.43-52
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    • 2010
  • Shield method is the tunnel boring method that propels a steel cylinder in the ground and excavates tunnels at once. After Marc Isambard Brunel started using the method for the Thames Riverbed Tunnel excavation in London, many kinds of TBM (Tunnel Boring Machine) developed and applied for the construction of road, railway, electricity channel, pipeline, etc. In comparison with NATM concept that allows to observe ground condition and copes with difficulty. The machine selected before starting construction is not able to be changed during construction in shield TBM. Therefore the machine should be designed based on the ground survey result and experiment, so that the tunnel might be excavated effectively by controlling penetration speed, excavation depth and cutter head speed according to the ground condition change. This research was conducted to estimate penetration depth, excavate speed, wear of disc cutter on Boondang Railway of the Han Riverbed Tunnel ground condition by TBM performance prediction models such as NTNU, $Q_{TBM}$, Total Hardness, KICT-SNU and compare the estimated value with the field data. The estimation method is also used to analyze the reason of poor excavation efficiency at south bound tunnel.

The Study on the Correlation between Unconfined Compressive Strength and Point Load Strength within the Gneiss Complex in Gyunggi Province (경기 동부 지역 편마암복합체내의 일축압축강도와 점하중강도의 상관관계에 관한 연구)

  • Cha, Areum;Song, Joonho;Choi, Hyunseok;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.8 no.1
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    • pp.21-26
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    • 2007
  • The strength evaluation of rocks is a very important factor in designing and constructing tunnels or underground excavation. However, it takes a lot of time and endeavor to perform the unconfined compressive strength test for practice and a number of tests are limited. In order to make up for this method, the point load strength test is suggested. Generally, the strength of a rock differs depending on its type and region. However, as people unite the Point Load Strength Indexes of various regions and types to use in practice in many cases, they find difficulty in analogizing the exact strength. The purpose of this study is suggestion of the value in construction site by analizing the relation of both unconfined compressive and point load strength in the Gyeonggi gneiss complex.

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Simplified Noise Modeling of GPS Measurements for a Fast and Reliable Cycle Ambiguity Resolution

  • Park, Byung-Woon;Kee, Chang-Don
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.535-540
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    • 2006
  • The relationship between the observable noise model and the satellite elevation angle can be modeled quite well by an exponential function.[Jin, 1996] Noise size and dependence on the elevation angle are, however, different for each observation and receiver type. Therefore, the coefficient determination of this model is an issue, and various methods including PR-CP, single difference, and time difference have been suggested. The limitations of them are difficulty to model the carrier phase noise and to eliminate bias. To overcome these disadvantages for using Jin's model, we suggest zero baseline double difference (DD) and noise sorting algorithm. Data DD technique in zero baseline is useful to eliminate all the troublesome GPS biases, and the remaining error is the sum of GPS measurement noises from two satellites. These DD residuals for hours should be sorted by the combination of satellite elevation angles, and then variance value of the residual for each combination can be estimated. Using these values, we construct an over-determined linear equation whose solution is a set of noise variance for each satellite elevation angle. With 24hr Trimble 4000ssi data, we easily worked out the coefficients of the noise model not only for pseudorange but also for carrier phase. We estimated the standard deviation of the measurement DD using our model, and plotted 1 and 3 sigma lines for every epoch to verify the representation of the residual error. 63.3% of pseudorange residual and 65.9% of phase error did not exceed the 1 sigma lines. Additionally, 99.2% and 99.5% of them lied within 3sigma line. These figures prove that the Gaussian property of measurement noise, and that the suggested model by our algorithm corresponds to the observable noise information.

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An Improvement on Testability Analysis by Considering Signal Correlation (신호선의 상관관계를 고려한 개선된 테스트용이도 분석 알고리즘)

  • 김윤홍
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.4 no.1
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    • pp.7-12
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    • 2003
  • The purpose of testability analysis is to estimate the difficulty of testing a stuck-at fault in logic circuits. A good testability measurement can give an early warning about the testing problem so as to provide guidance in improving the testability of a circuit. There have been researches attempting to efficiently compute the testability analysis. Conventional testability measurements, such as COP and SCOAP, can calculate the testability value of a stuck-at fault efficiently in a tree-structured circuit but may be very inaccurate for a general circuit. The inaccuracy is due to the ignorance of signal correlations for making the testability analysis linear to a circuit size. This paper proposes an efficient method for computing testability analysis, which takes into account signal correlation to obtain more accurate testability. The proposed method includes the algorithm for identifying all reconvergent fanouts in a given n circuit and the gates reachable from them, by which information related to signal correlation is gathered.

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The Strategy of City Brand Activation by Confusion Content - Case Study of Andong City and Qufu City (유교문화 콘텐츠를 활용한 도시브랜드 활성화 방안 연구 - 안동시와 중국 곡부시 사례를 중심으로)

  • Ha, Kyu-Soo;Moon, Ji-Eun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.252-263
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    • 2016
  • This study considered the factors of city brand reinforcement and city revitalization through a case study of two cities that were successful in revitalizing using a brand strategy. World leading cities are securing city competitiveness through the culture resources, particularly traditional culture, as a key asset to highlight the cities' uniqueness in increasing their value. The Confucianism influence on Korean traditional culture has a valuable content like etiquette, ritual ceremony, food, education, etc. as well as culture heritage in historical architecture. Therefore, it can be used as the city's assets to promote it worldwide. On the other hand, there is difficulty in preserving most Confucianism culture content and the intangible cultural properties have been neglected. This needs to be applied actively to be used on a city brand strategy. This study reviewed the successful case of Andong city in Korea and Qufu city in Sandong, China and suggests ways of raising the cities' brand power.

A Study on the Minimum Safe Distance Under the Low Speed Sailing of T.S. HANBADA (실습선 한바다호의 저속 항해시 최소안전 이격거리에 관한 연구)

  • Park Young-Soo;Ji Sang-Won;Lee Yun-Sok;Jung Chang-Hyun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2005.10a
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    • pp.5-10
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    • 2005
  • T.S. HANBADA will navigate to maintain the adequate distance between own ship and other ships safely for about 17 hours on the about 2 kts. On the above situation, M broadcasting station requires to maintain the distance from 100m to 500m between ships. This paper aims to calculate the minimum safe distance between ships, the distance is assessed by using ES Model which is a quantitative model for evaluating the difficulty of shiphandling. After marine traffic flow simulation, minimum safe distance for HANBADA on the 2kts is about 260m based ES value. On this paper, the result was compared about its distance to the actual navigating distance.

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A Study on the Innovative characteristics and the Adoption of Casual Hanbok in the late of 1990s (90년대 후반 생활한복의 혁신특성과 채택에 관한 연구)

  • 최은영;이은영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.7
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    • pp.1093-1104
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    • 2002
  • In this study, the diffusion phenomenon of casual Hanbok which started in the mid 1990s and has been widely spread ever since with innovative features in design, materials, etc., was reviewed. Through the interviews of 45 People who have worn casual Hanbok the advantages and disadvantages of casual Hanbok related to its innovative characteristics were recorded and analyzed. Through the questionnaires distributed to 482 adults living in Seoul, Busan, and Darjeon, the factors related to the adoption of casual Hanbok were examined. The following are the results from the empirical study. First the adoption of contemporary casual Hanbok is due to the consumers′ positive response to the excellence of casual Hanbok′s various innovative characteristics. What the consumers perceived as innovative characteristics of casual Hanbok in the survey results validated the findings of the depth interview, identifying seven subcategories of the innovative characteristics of casual Hanbok; aesthetics, positive training effect on body and mind, difficulty in we, practicality, psychological attachment for "Our Clothes", economic efficiency, and symbolic compatibility. And consumers who think highly of such spiritual and identity values as national consciousness, nature affiliation, and community consciousness, had high evaluation to casual Hanbok However, consumers′ prejudice against Hanbok that Hanbok is for old people, uncomfortable, and not suitable to modern life, tuned out to have a negative influence on the adoption. From these results, it can be concluded that casual Hanbok of the late 1990s is a fashion with innovative characteristics, different from the one in the l980s worn by the demonstrators of popular movements and democratic movements, and it emerged as a new symbol with the characteristics of cultural movement like community consciousness and nature affiliation.

Multi-temporal Analysis of Deforestation in Pyeongyang and Hyesan, North Korea

  • Lee, Sunmin;Park, Sung-Hwan;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.32 no.1
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    • pp.1-11
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    • 2016
  • Since forest is an important part of ecological system, the deforestation is one of global substantive issues. It is generally accepted that the climate change is related to the deforestation. The issue is worse in developing countries because the forest is one of important natural resources. In the case of North Korea, the deforestation is on the rise from forest reclamation for firewood collection and food production. Moreover, a secondary effect from flood intensifies the damage. Also, the political situation in North Korea presents difficulty to have in-situ measurements. It means that the accurate information of North Korea is nearly impossible to obtain. Thus, assessing the current situation of the forest in North Korea by indirect method is required. The objective of this study is to monitor the forest status of North Korea using multitemporal Landsat images, from 1980s to 2010s. Since the deforestation in North Korea is caused by local residents, we selected two study areas of high population density: Pyeongyang and Hyesan. In North Korea, most of clean Landsat images are acquired in fall season. The fall images have an advantage that we can easily distinguish agriculture areas from forest areas, also have an disadvantage that the forests cannot be easily identified because some of trees have turned red. To identify the forests exactly, we proposed a modified Normalized Difference Vegetation Index (mNDVI) value. The deforestation in Pyeongyang and Hyesan was analyzed by using mNDVI. The dimension of forest has decreased approximately 36% in Pyeongyang for 27 years and approximately 25% in Hyesan for 16 years. The results show that the forest areas in Pyeongyang and Hyesan have been steadily reduced.

Securing Land Rights in Myanmar Development Project : Focusing on Foreign Investment and Land System (미얀마 개발사업 추진시 토지권리 확보방안 : 외국인투자 및 토지제도를 중심으로)

  • Jeong, Yeun-Woo
    • Land and Housing Review
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    • v.8 no.3
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    • pp.145-159
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    • 2017
  • Despite the longing for democracy of most people, Myanmar has missed opportunities for social and economic development by military dictatorship. However, since 2010, the civilian government has gained new opportunities for reform. After turning to economic reform, developed countries such as the US and EU lifted the economic sanctions that they had taken in the past. As a result, it is growing rapidly compared to neighboring countries due to attracting foreign capital, tariff benefits on export items, and expansion of industrial infrastructure. Despite the increased investment value due to economic growth and democratization, the complex and customary land system of Myanmar must be an uneasy factor in securing stable land rights when entering overseas markets. Therefore, this study sought the method of securing the land rights in the development project through the analysis of the foreign investment system in Myanmar and the investigation of joint development cases. The results of this study are as follows. First, the acquisition of land use rights at the early stage of development can be considered through the foreign investment system. Under the Foreign Investment Law and Myanmar Investment Law, the land can be used for up to 70 years, and Under the Special Economic Zone Law, the land can be used for up to 75 years. Second, in relation to land compensation, it is required to establish a detailed resettlement plan for the indigenous people as the difficulty of land acquisition is expected due to the recent democratization trend and strengthening the voice of residents. Third, land use at the operational stage can be achieved by leasing the land from developers, and this will be the most realistic plan at present. In other words, the developer can directly develop the land created under the Foreign Investment Law and the Special Economic Zone Law, or Sub-lease and transfer the land use right to a third party.