• Title/Summary/Keyword: Effort Estimation

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Estimating Population Density of Leopard Cat (Prionailurus bengalensis) from Camera Traps in Maekdo Riparian Park, South Korea

  • Park, Heebok;Lim, Anya;Choi, Tae-Young;Lim, Sang-Jin;Park, Yung-Chul
    • Journal of Forest and Environmental Science
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    • v.33 no.3
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    • pp.239-242
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    • 2017
  • Although camera traps have been widely used to understand the abundance of wildlife in recent decades, the effort has been restricted to small sub-set of wildlife which can mark-and-recapture. The Random Encounter Model shows an alternative approach to estimate the absolute abundance from camera trap detection rate for any animals without the need for individual recognition. Our study aims to examine the feasibility and validity of the Random Encounter Model for the density estimation of endangered leopard cats (Prionailurus bengalensis) in Maekdo riparian park, Busan, South Korea. According to the model, the estimated leopard cat density was $1.76km^{-2}$ (CI 95%, 0.74-3.49), which indicated 2.46 leopard cats in $1.4km^2$ of our study area. This estimate was not statistically different from the previous leopard cat population count ($2.33{\pm}0.58$) in the same area. As follows, our research demonstrated the application and usefulness of the Random Encounter Model in density estimation of unmarked wildlife which helps to manage and protect the target species with a better understanding of their status.

Study of CMM base Information Technology company level estimation (CMM 기반 정보기술 업체 수준평가에 관한 연구)

  • Kim Tai-Dal
    • Journal of Internet Computing and Services
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    • v.5 no.1
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    • pp.33-39
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    • 2004
  • In this paper, so that government official in target extent of relevant shame capacitates CMM measuring achievement result by each process as quantitative because do standard, repeat and achieves gap analysis and estimation solidify knowledge management of information base enabling "Quality control, production management, cost control, integral management of knowledge", Solidify customer service through "high-quality, differentiation" of information. Establish administration and supervision item to reach 4 steps level in information ability measurement in formation to prove business efficiency through process optimization and improves formation maturity through voluntary effort of formation continuously. Suggested model who analyze and evaluates application in domestic SI specialty company.I specialty company.

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The Investigation on Application of Construction Waste Unit to Establish Resource Recycling System through Case Study (건설폐기물 자원순환체계 구축을 위한 발생원단위 적용에 관한 연구)

  • Son, Byeung Hun;Hong, Won Hwa
    • KIEAE Journal
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    • v.10 no.5
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    • pp.181-186
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    • 2010
  • Research on construction waste unit was in progress in the 1995 when 'Proper Disposal and Recycling Measures for Construction Waste' was made by the Seoul Development Institute. Such an effort has been made in order to cope with the lack of natural resources in Korea and to utilize the reusable resources. Furthermore, these efforts have also increased due to the improved standing of Korea in the international community. A large number of residential buildings were built in the response to the government's policy by increasing the supply of houses between the 1970's and 1980's. In 2000, more reconstruction and redevelopment was done because of the aged buildings and change of use for those buildings. And the project has been actively promoted until now, which caused a sharp increase in the generation volume of construction waste. In Korea, 8 kinds of construction waste unit, including the standard construction manpower and materials estimation, are introduced. Currently, they provide standards to different building categories and waste properties while for construction sites different standards are applied. This study aims to measure the actual amount of construction waste after sample buildings are dismantled and analyzes the estimation of the waste quantity by using various standard units. Through comparison, this study will figure out the differences among the standard units in order to find out how to apply the standard units properly. Moreover, this research will provide practical measures to apply such units to construction sites.

Software Maintenance Cost Estimation using RBF Network (RBF망을 이용한 소프트웨어 유지보수 비용 추정)

  • 박주석;정기원
    • Journal of KIISE:Software and Applications
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    • v.31 no.5
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    • pp.555-562
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    • 2004
  • Software industry has put more emphasis on maintenance and enhancement work than on the new development. The existing effort estimation models can still be applied to maintenance projects, though modifications are needed. This paper suggests a way to estimate the size of a maintenance project from the regression analysis of ISBSG's benchmarking data. First of all, among the 3 elements(addition, modification and deletion of the program) which influences the software cost, we selected and classified 4 groups from a total of 8 which shows actual maintenance cost from ISBSG's data. Moreover, we developed statistical model and a model which uses RBF(Radial Basis Function) Network and after evaluating each functions we concluded that the RBF Network is superior to the statistical model.

A two-stage and two-step algorithm for the identification of structural damage and unknown excitations: numerical and experimental studies

  • Lei, Ying;Chen, Feng;Zhou, Huan
    • Smart Structures and Systems
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    • v.15 no.1
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    • pp.57-80
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    • 2015
  • Extended Kalman Filter (EKF) has been widely used for structural identification and damage detection. However, conventional EKF approaches require that external excitations are measured. Also, in the conventional EKF, unknown structural parameters are included as an augmented vector in forming the extended state vector. Hence the sizes of extended state vector and state equation are quite large, which suffers from not only large computational effort but also convergence problem for the identification of a large number of unknown parameters. Moreover, such approaches are not suitable for intelligent structural damage detection due to the limited computational power and storage capacities of smart sensors. In this paper, a two-stage and two-step algorithm is proposed for the identification of structural damage as well as unknown external excitations. In stage-one, structural state vector and unknown structural parameters are recursively estimated in a two-step Kalman estimator approach. Then, the unknown external excitations are estimated sequentially by least-squares estimation in stage-two. Therefore, the number of unknown variables to be estimated in each step is reduced and the identification of structural system and unknown excitation are conducted sequentially, which simplify the identification problem and reduces computational efforts significantly. Both numerical simulation examples and lab experimental tests are used to validate the proposed algorithm for the identification of structural damage as well as unknown excitations for structural health monitoring.

Development of an uncertainty quantification approach with reduced computational cost for seismic fragility assessment of cable-stayed bridges

  • Akhoondzade-Noghabi, Vahid;Bargi, Khosrow
    • Earthquakes and Structures
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    • v.23 no.4
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    • pp.385-401
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    • 2022
  • Uncertainty quantification is the most important challenge in seismic fragility assessment of structures. The precision increment of the quantification method leads to reliable results but at the same time increases the computational costs and the latter will be so undesirable in cases such as reliability-based design optimization which includes numerous probabilistic seismic analyses. Accordingly, the authors' effort has been put on the development and validation of an approach that has reduced computational cost in seismic fragility assessment. In this regard, it is necessary to apply the appropriate methods for consideration of two categories of uncertainties consisting of uncertainties related to the ground motions and structural characteristics, separately. Also, cable-stayed bridges have been specifically selected because as a result of their complexity and the according time-consuming seismic analyses, reducing the computations corresponding to their fragility analyses is worthy of studying. To achieve this, the fragility assessment of three case studies is performed based on existing and proposed approaches, and a comparative study on the efficiency in the estimation of seismic responses. For this purpose, statistical validation is conducted on the seismic demand and fragility resulting from the mentioned approaches, and through a comprehensive interpretation, sufficient arguments for the acceptable errors of the proposed approach are presented. Finally, this study concludes that the combination of the Capacity Spectrum Method (CSM) and Uniform Design Sampling (UDS) in advanced proposed forms can provide adequate accuracy in seismic fragility estimation at a significantly reduced computational cost.

Hydrologic Calibration of HSPF Model using Parameter Estimation (PEST) Program at Imha Watershed (PEST를 이용한 임하호유역 HSPF 수문 보정)

  • Jeon, Ji-Hong;Kim, Tae-Il;Choi, Donghyuk;Lim, Kyung-Jae;Kim, Tae-Dong
    • Journal of Korean Society on Water Environment
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    • v.26 no.5
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    • pp.802-809
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    • 2010
  • An automatic calibration tool of Hydrological Simulation Program-Fortran (HSPF), Parameter Estimation (PEST) program, was applied at the Imha lake watershed to get optimal hydrological parameters of HSPF. Calibration of HSPF parameters was performed during 2004 ~ 2008 by PEST and validation was carried out to examine the model's ability by using another data set of 1999 ~ 2003. The calibrated HSPF parameters had tendencies to minimize water loss to soil layer by infiltration and deep percolation and to atmosphere by evapotranspiration and maximize runoff rate. The results of calibration indicated that the PEST program could calibrate the hydrological parameters of HSPF with showing 0.83 and 0.97 Nash-Sutcliffe coefficient (NS) for daily and monthly stream flow and -3% of relative error for yearly stream flow. The validation results also represented high model efficiency with showing 0.88 and 0.95, -10% relative error for daily, monthly, and yearly stream flow. These statistical values of daily, monthly, and yearly stream flow for calibration and validation show a 'very good' agreement between observed and simulated values. Overall, the PEST program was useful for automatic calibration of HSPF, and reduced numerous time and effort for model calibration, and improved model setup.

A Study of Development Gains Estimation in Building Land Development Projects (택지개발사업의 개발이익 추계에 대한 연구)

  • Kim, Yong-Chang
    • Journal of the Korean association of regional geographers
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    • v.12 no.5
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    • pp.595-613
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    • 2006
  • In the debates of development gains, the general rule is that it results from actions other than those of the landowner, most notably of the public sector as in granting of permissions for the development of specific land uses and densities or through infrastructure investments, or of socio-economic forces due to a general capital accumulation in space. A huge academic literature has investigated the development gains capture that refers to the process by which a portion of or all land value increments attributed to the community effort are recouped by the public sector. Policy instruments for applying development gains capture are based on deepening land value taxation, financing infrastructure, controling land use. But one of the most basic for the efficient policy implementation is the accurate estimation of development gains. This paper estimates the development gains generated by the total 204 building land projects of Korea Land Corporation and Korea National Housing Corporation since 1995.

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From Theory to Implementation of a CPT-Based Probabilistic and Fuzzy Soil Classification

  • Tumay, Mehmet T.;Abu-Farsakh, Murad Y.;Zhang, Zhongjie
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.1466-1483
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    • 2008
  • This paper discusses the development of an up-to-date computerized CPT (Cone Penetration Test) based soil engineering classification system to provide geotechnical engineers with a handy tool for their daily design activities. Five CPT soil engineering classification systems are incorporated in this effort. They include the probabilistic region estimation and fuzzy classification methods, both developed by Zhang and Tumay, the Schmertmann, the Douglas and Olsen, and the Robertson et al. methods. In the probabilistic region estimation method, a conformal transformation is used to determine the soil classification index, U, from CPT cone tip resistance and friction ratio. A statistical correlation is established between U and the compositional soil type given by the Unified Soil Classification System (USCS). The soil classification index, U, provides a soil profile over depth with the probability of belonging to different soil types, which more realistically and continuously reflects the in-situ soil characterization, which includes the spatial variation of soil types. The CPT fuzzy classification on the other hand emphasizes the certainty of soil behavior. The advantage of combining these two classification methods is realized through implementing them into visual basic software with three other CPT soil classification methods for friendly use by geotechnical engineers. Three sites in Louisiana were selected for this study. For each site, CPT tests and the corresponding soil boring results were correlated. The soil classification results obtained using the probabilistic region estimation and fuzzy classification methods are cross-correlated with conventional soil classification from borings logs and three other established CPT soil classification methods.

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Development of IMEP Estimation and Control Algorithm Using In-Cylinder Difference Pressure for Passenger Diesel Engines (승용 디젤 엔진의 실린더 차이 압력을 이용한 IMEP 추정 및 제어 알고리즘 개발)

  • Chung, Jae-Sung;Oh, Seung-Suk;Park, In-Seok;SunWoo, Myoung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.9
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    • pp.915-921
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    • 2012
  • In this study, we propose a new method for estimating the IMEP using difference pressure, which is the pressure difference between the cylinder pressure and the motoring pressure. The estimated IMEP, denoted as $IMEP_{diff}$, optimizes the theoretical IMEP calculation range based on the fact that the difference pressure exists between the start and the end of combustion. $IMEP_{diff}$ is verified to have a high linear correlation with IMEP with $R^2$ of 0.9955. The proposed method can estimate the IMEP with 21% of the cylinder pressure data and 31% of the calculation effort compared to the theoretical IMEP calculation method, and therefore, it has great potential for real-time implementations. The estimation and control performance of $IMEP_{diff}$ is validated by engine experiments, and by controlling $IMEP_{diff}$, the torque variation between the cylinders was reduced.