• Title/Summary/Keyword: Alternative methods

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Alternative Methods for Assessments of DEMs' Erros (DEM의 오차 평가 방법에 관한 연구)

  • Hwang, Chul-Sue
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.23-34
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    • 1999
  • The most widely used measure for indicating the accuracy of DEM is RMSE(nut Mean Square Error), which is used by many national mapping agencies such as the USGS and the Ordnance Survey. Its prevalent use can be followed by the relative ease of calculation and understanding the concepts. However, there are many problems with the measure and the way from which it is often derived. First of all, the index does not involve my description of the mean donation between the two measures of elevation,. This means that it cannot interpret the distributions or patterns of errors involved in DEMs. The distribution of errors in DEMs will show some forms of spatial patterning. In order to explore the real quality of DEMs as a useful database, alternative approaches are needed. In this paper, we examined so called ESDA(Exploratory Spatial Data Analysis) approaches, which were attributed by both aspatial and spatial exploration methods. Our experimental research shows that even simple ESDA methods reveal new aspects of errors, especially spikes, striation, and terracing effect in DEMs, which my be ignored by RMSE measure.

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A Study on the Analysis of Isothiazolinone Components by High Performance Liquid Chromatography (고성능액체크로마토그래피에 의한 Isothiazolinone Components의 분석에 관한 연구)

  • 김종규;이덕희
    • Journal of Environmental Health Sciences
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    • v.18 no.2
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    • pp.102-105
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    • 1992
  • Introduction : Isothiazolinone product is one of new preservatives used in cooling tower, paper mill, and general industrial waters.l) It is also effective in controlling bacteria and fungi in the manufacture and storage of dispersed pigments, such as kaolin clays, titanium dioxide, calcium carbonate and others\ulcorner Its broad-spectrum activity, excellent physical and chemical compatibility with anionic, nonionic and cationic surfactants and most organic and inorganic compounds and low toxicity at recommended use levels provide formulators with an effective, economical, and environmentally acceptable alternative to other commercial biocides. It dose not contain or generate formaldehyde and is easy to formulate (1.5% solution is supplied as an aqueous solution), so that it gains advantage over the other preservatives. The active ingredients of the isothiazolinone product are unchlorinated compound (2-methyl-4-isothiazolin-3-one) and chlorinated one (5-chloro-2-methyl-4-isothiazolin-3-one). Methods preferred for the analysis of preservatives are chromatographic methods, especially high performance liquid chromatograph (HPLC). Although several methods were satisfactory in respect to separation, no offical method has been published for the isothiazolinone components. This study was performed to search for an alternative method in order to show flexible operating conditions of HPLC and to reduce assay time.

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The Trend of CM at Risk in the U.S Construction Market (미국 CM at Risk 시장 동향 및 시사점)

  • Chang, Chul-Ki
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2006.11a
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    • pp.67-73
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    • 2006
  • Alternative project delivery methods including design-build and CM at Risk have evolved as a means of meeting owner's diverse needs and implementing project efficiently with limited budget and time in more competitive construction environment. It is time to consider adopting alternative project delivery methods, especially CM at Risk, for domestic construction industry to enhance competitiveness and to provide various options for owners so that they can select more appropriate project delivery methods for the facility being planned. This research report derives suggestions from investigating how CM at Risk has been evolved in the US construction market. Besides the analysis of CM at Risk market in the US construction industry, the characteristics of companies whose market share are in Top 100, the type of facility usually built by this method were investigated. Based on the analysis of CM at Risk in the US, the prepositions in adopting CM at Risk to domestic construction industry and the possibility of adopting this method have been identified.

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Securing the Private Key in the Digital Certificate Using a Graphic Password (그래픽 비밀번호를 활용한 공인인증서 개인키 보호방법에 관한 연구)

  • Kang, Byung-Hoon;Kim, Beom-Soo;Kim, Kyung-Kyu
    • The Journal of Society for e-Business Studies
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    • v.16 no.4
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    • pp.1-16
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    • 2011
  • A digital certificate mandated by the Electronic Signature Act has become familiar in our daily lives as 95% of the economically active population hold certificates. Due to upgrades to 256 bit level security that have become effective recently, the security and reliability of digital certificates are expected to increase. Digital certificates based on Public Key Infrastructure (PKI) have been known as "no big problem," but the possibility of password exposure in cases of leaked digital certificates still exists. To minimize this vulnerability, various existing studies have introduced alternative password methods, expansion of certificate storage media, and multiple certification methods. These methods perform enhanced functions but also have limitations including the fact that the secureness of passwords is not guaranteed. This study suggests an alternative method for enhancing the level of password secureness as a way to improve password security. This new method improves security management and enhances the convenience of using digital technologies. The results may be used for developing digital certificate related security technologies and research in the future.

Complications and Difficulties in Alternative Methods of Conception (인공수태(人共受胎)의 합병증(合倂症)과 난점(難點)에 관(關)한 연구(硏究))

  • Ku, Pyong-Sahm
    • Clinical and Experimental Reproductive Medicine
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    • v.14 no.1
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    • pp.29-35
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    • 1987
  • Alternative methods were used in the field of infertility as the latest means for the treatment of misconception. Artificial insemination, which has been commonly used already, IVF-ET and GIFT are also used as artificicial method for conception presently. Appling such methods to the patient, following three categories should be considered; first, there should be an understanding and an agreement from the patient, second, if possible, reduce the cost of hospital expense and relieve physical and emotional problems of the patient, and third, increcrsing the pregnancy rate. Under these considerations, complication and pitfalls of artifical inseminations are a big burden to the physian and the patient. Though the conicicental complications are relatively very rare, detailed laboratoy tests, carefull examinations, and follow-up studies are necessary. In the distribution of the age groups, 40.3% was in the 25 to 29 years group, 30 to 34 years was 45%. 35 to 39 years was 8% and only 3.2% was above the 40 age groups. The range of infertile periods were from 1 to 17 years, and half of the patients were over 5 years, the other group 20% in 3 years and 2 to 4 years were 10%. Among 159 cycles of artificial insemination, there were complications such as infection(1.9%) and discomfort(5%) and abnormal bleeding (0.6%). During pregnancy, clinical abortion (1.9%) and toxemia (2.5%) were shown. Sex of new born infants were, male (68%) and female (31%). Fortunately, there were no cases of psychological complication and genetic abnormality. Indications of artificial insemination for male factors were aspermia (2.5%), azoospermia (28.8%), oligospermia (26.4%) and asthenozoospermia (1.8%), for female factors were irregular cycle (11.7%) and dysmucorrhea.

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THE PRELIMINARY INVESTIGATION OF CURRENT CONSTRUCTION PAYMENT PRACTICES IN THE UK CONSTRUCTION PROJECTS

  • C.H. Wong;A. Kaka;C. Fortune;D. Langford
    • International conference on construction engineering and project management
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    • 2007.03a
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    • pp.800-809
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    • 2007
  • Current payment methods have many faults which are detrimental to the formation and completion of a project. This includes the use of unfair payment terms, pricing strategies and payment mechanisms between the contracting parties. This resulted in being criticised and remain in doubt, the use of current payment methods to reward good contractors and to distinguish poorly performed construction firms. In order to have an insight into this issue, a structured survey was conducted amongst UK construction practitioners. It was found that traditional pricing methods (i.e. lump sum and unit price), payment methods (i.e. interim valuation) and retention still dominate current practice. The empirical findings show that there are significant differences in the use of pricing and payment methods (when making and receiving payments) in construction. Significant differences also found in the factors affecting the choice of pricing methods when making (and receiving) construction payments. The paper concludes with analysis of the findings and future direction of research in payment systems is also provided.

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Subjective Assessment of Simulated Heavy Floor Impact Sounds for Alternative Rating Method (현행 중량바닥충격음 평가방법 개선을 위한 주관평가실험)

  • Shin, Hoon;Back, Geon-Jong;Song, Min-Jeong;Jang, Gil-Soo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.11a
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    • pp.581-586
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    • 2008
  • This study aims to examine the existing single rating index in terms of level reduction limit of heavy-weight floor impact sound. To achieve this goal, sounds which have same loudness according to rating methods were suggested to subjects. And followings are results. 1) The rating method of measurement frequency level average is more suitable than that of other methods which are dependent on specific frequency for rating heavy-weight floor impact sound. 2) Level average for measurement frequency of 31.5Hz - 500Hz is more correspondent to psycho-acoustic response than that of measurement frequency of 63Hz - 500Hz which is for KS F 2863-2, existing rating method.

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On the Opimal Decision Making using the Eigenvector Methods (고유벡터 법을 이용한 최적 의사결정에 관한 연구)

  • Chung Soon-Suk
    • Proceedings of the Safety Management and Science Conference
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    • 2006.04a
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    • pp.123-131
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    • 2006
  • Multi-criteria decision making is deducing the relative importance in the criterion of decision making and each alternative which is able to making a variety of choices measures the preferred degree in the series of low-raking criterions. Moreover, this is possible by synthesizing them systematically. In general, a fundamental problem decision maker solve for multi-criteria decision making is evaluating a set of activities which are considered as the target logically, and this kind of work is evaluated and synthesized by various criterions of the value which a chain of activities usually hold in common. In this paper, we are the eigenvector methods in weights calculating. For the purpose of making optimal decision, the data of five different car models are used. For computing, we used Visual Numerica Version 1.0 software package.

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CONFIDENCE INTERVALS ON THE AMONG GROUP VARIANCE COMPONENT IN A REGRESSION MODEL WITH AN UNBALANCED ONE-FOLD NESTED ERROR STRUCTURE

  • Park, Dong-Joon
    • Proceedings of the Korean Statistical Society Conference
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    • 2002.11a
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    • pp.141-146
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    • 2002
  • In this article we consider the problem of constructing confidence intervals for a linear regression model with nested error structure. A popular approach is the likelihood-based method employed by PROC MIXED of SAS. In this paper, we examine the ability of MIXED to produce confidence intervals that maintain the stated confidence coefficient. Our results suggest the intervals for the regression coefficients work well, but the intervals for the variance component associated with the primary level cannot be recommended. Accordingly, we propose alternative methods for constructing confidence intervals on the primary level variance component. Computer simulation is used to compare the proposed methods. A numerical example and SAS code are provided to demonstrate the methods.

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Estimates of the Economic Value of Houshold Work by Fulltime Home Makers (가사노동의 경제적 가치평가에 관한 연구)

  • 김선희
    • Journal of the Korean Home Economics Association
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    • v.28 no.2
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    • pp.73-89
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    • 1990
  • The aim of the present study is to estimates the economic value of household work done by fulltime home makers, using alternative methods of valuation household work in Pusan Korea. Eight findings, five different methods -Self Estimation by Home Makers, Reservation Wage, Opportunity Cost, Individual function Cost, Replacement Cost(Visiting Housekeeper, Housekeeper, General Managemet, Housekeeper & General Management)- are tried for the estimation of economic value of household work. The results of this study can be outlined as follows : 1) The economic value of household work varies substantially by the methods of estimating. The averages are : 2) The economic value of household work varies with the level of education, ages, the number of children, the stage of FLC in all method of estimation, and the level of income in self estimation by home makers, Reservation wage. Specially, FLC revealed good explanation variable in method of estimation as input household work time. 3) The gap between two-day survey and three-day survey in household work time questionaire didn't so much.

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