다측면적 청소년 역량강화사업의 성과 평가에서 지표와 지수의 활용 사례 비교 연구: 한국 월드비전 부룬디 사업 사례를 중심으로

임진호,윤영준,조윤호,김미정,박미림 국제개발협력학회 2023 국제개발협력연구 Vol.15 No.4

Purpose: This study examines how 'indicator' and 'index' are applied differently through the case of actual project, and what the pros and cons of each are. Based on this study, implications for effective use of indicator and index are derived. Originality: In order to effectively evaluate multidimensional coucomes such as poverty and human competence, it is necessary to use a index rather than a single indicator. Accordingly, there is an urgent need for various investigations of the use of multidimensional preformance index. Methodology: The performance evaluation of the 'Burundi BTS Project' as a case study was simultaneously applied using a method using 'indicators' based on PDM and a method using 'index' based on the Alkire-Foster Method. In particular, the 'Post-Only Non-homogeneous Comparison Design' was used as a method to conduct performance evaluation of the 'Burundi BTS Project'. Result: As a result of performance evaluation using the PDM performance indicators, it was confirmed that the project was successful in 6 out of 8 indicators. As a result of performance evaluation using the LIFE index, the number of youth deprived of competence decreased by 42.8%, and the degree to which youth who lacked competence reached their target competence level improved by 17.2%. The LIFE index was also have improved by 54%. In addition, it was found that the method using ‘index’ was more appropriate, especially in projects that evaluate multidimensional outcomes such as changes in youth competence. Conclusion and Implication: Most international development cooperation projects generally evaluate performance using indicators. However, it is necessary to conduct diverse and specialized case studies on how to use index to effectively and efficiently evaluate performance outcomes according to the purpose of the project.

N2 Method를 이용한 RC 중간모멘트 연성골조의 반응수정계수 및 내진성능 평가

윤정배,이철호,최정욱,송진규 한국지진공학회 2002 한국지진공학회논문집 Vol.6 No.6

반응수정계수는 구조물의 비탄성 거동을 설계에 반영하고 설계지진력 산정시 설계강도를 탄성범위 이내로 저감시키기 위한 목적으로 사용하고 있다. 그러나 설계코드에서 채택하고 있는 반응수정계수는 과거의 지진피해로부터 관찰된 보편적 구조성능에 기인한 경험치이므로, 주기에 따른 동적성능과 구조 시스템의 구성에 따른 내진성능을 정확히 대변하지 못하고 있다. 본 연구에서는 중간모멘트 연성골조를 대상으로 N2 Method를 이용하여 반응수정계수와 내진성능을 평가하였으며, 그 결과를 미국의 IBC 2000 코드와 비교하여 이론적 타당성을 검증하였다. 해석결과 코드에 제시된 반응수정계수와 잘 부합되는 것으로 나타났으나, 동일한 구조시스템의 경우에도 주기에 따라 비교적 큰 차이를 보였다. 성능목표에 따른 사용성 기준을 설정하여 IDI를 평가한 결과, 설계지진에 대한 성능목표가 건물에 대한 내진성능을 대변하기는 어려우며 PBD(Performance Based Design)에 의거한 합리적인 접근이 필요한 것으로 판단된다. Response Modification Factor(R-factor) approach is currently implemented to reflect inelastic ductile behavior of the structures and to reduce elastic spectral demands from earthquakes to the design level. However R factors were set empirically and simply based on the professional committee consensus on observed performance of building structures during past earthquakes. Consequently some major shortcomings linked to the current R factor approach have been pointed out. Using reinforced concrete intermediate moment-resisting frames(RC IMRFs), an analytical procedure is presented in this paper to establish R factor rationally. To this end, analytical R values were evaluated based on N2 Method and compared with the values recommended by IBC 2000. Overall, the analytical results correlated well with the code values. However the results also revealed that R factor might strongly depend on the system fundamental period. As evidenced by the interstory drift index(IDI) analysis results of this study, current R-factor based(or, Life Safety based) design tends to fail in fulfilling other implicit and hopeful performance objectives such as immediate Occupancy and Collapse Prevention. Performance based design(PBD) appears to be a promising approach to meet the multi level seismic performance objectives assigned to the building structures of nowadays.

A Study for Robustness of Objective Function and Constraints in Robust Design Optimization

Lee Tae-Won The Korean Society of Mechanical Engineers 2006 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.20 No.10

Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

A Study for Robustness of Objective Function and Constraints in Robust Design Optimization

Tae Won Lee 대한기계학회 2006 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.20 No.10

Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

Comparison of Sensitivity Analysis Methods for Building Energy Simulations in Early Design Phases: Once-at-a-time (OAT) vs. Variance-based Methods

김선혜 한국생태환경건축학회 2016 한국생태환경건축학회 논문집 Vol.16 No.2

Purpose: Sensitivity analysis offers a good guideline for designing energy conscious buildings, which is fitted to a specific building configuration. Sensitivity analysis is, however, still too expensive to be a part of regular design process. The One-at-a-time (OAT) is the most common and simplest sensitivity analysis method. This study aims to propose a reasonable ground that the OAT can be an alternative method for the variance-based method in some early design scenarios, while the variance-based method is known adequate for dealing with nonlinear response and the effect of interactions between input variables, which are most cases in building energy simulations. Method: A test model representing the early design phase is built in the DOE2 energy simulations. Then sensitivity ranks between the OAT and the Variance-based methods are compared at three U.S. sites. Result: Parameters in the upper rank by the OAT do not much differ from those by the Main effect index. Considering design practices that designers would chose the most energy saving design option first, this rank similarity between two methods seems to be acceptable in the early design phase.

A fast damage detecting technique for indeterminate trusses

Arash Naderi,Mohammad Reza Sohrabi,Mohammad Reza Ghasemi,Babak Dizangian 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.75 No.5

Detecting the damage of indeterminate trusses is of major importance in the literature. This paper proposes a quick approach in this regard, utilizing a precise mathematical approach based on Finite Element Method. Different to a general two-step method defined in the literature essentially based on optimization approach, this method consists of three steps including Damage-Suspected Element Identification step, Imminent Damaged Element Identification step, and finally, Damage Severity Detection step and does not need any optimizing algorithm. The first step focuses on the identification of damage-suspected elements using an index based on modal residual force vector. In the second step, imminent damage elements are identified among the damage-suspected elements detected in the previous step using a specific technique. Ultimately, in the third step, a novel relation is derived to calculate the damage severity of each imminent damaged element. To show the efficiency and quick function of the proposed method, three examples including a 25-bar planar truss, a 31-bar planar truss, and a 52-bar space truss are studied; results of which indicate that the method is innovatively capable of suitably detecting, for indeterminate trusses, not only damaged elements but also their individual damage severity by carrying out solely one analysis.

도식적 기저유출분리기법의 적용에 관한 사례 연구

강태욱,이남주 한국수자원학회 2021 한국수자원학회논문집 Vol.54 No.4

Baseflow constitutes most of the streamflow during the dry season and it is an important factor for stream management. In this study, four techniques for separating baseflow from the streamflow were applied to two target areas to examine the applicability. The baseflow separation techniques used in the analysis are all graphical methods, which are fixed interval method (FIM), sliding interval method (SIM), local minimum method (LMM), and PART programs based on the N-day method. The target areas are the Daeri and Cheongsong stage stations in the Nakdong River Basin where the streamflow was measured continuously for 5 years. We evaluated the appropriateness of the results for baseflow separation methods by examining the indexes for model assessment (NSE, PBIAS, RSR), baseflow index, and shape of baseflow separated from a flood hydrograph. It was analyzed that the FIM, SIM, and LMM methods included some errors in separating the baseflow from streamflow, whereas the PART program results were found to be the best. 유역의 기저유량은 갈수기 하천유량의 대부분을 차지하므로 하천 관리에 있어 중요한 요소이다. 이 연구에서는 하천유량으로부터 기저유량을 분리하는 4가지의 기저유출분리기법을 2개의 대표 지점에 적용하여 적용성을 검토하였다. 분석에 사용된 기저유출분리기법은 모두 도식적 방법으로서, N-day법에 근거한 FIM, SIM, LMM 기법과 PART 프로그램이다. 적용된 지역은 다년간 연속적으로 유량이 측정된 낙동강 유역의 대리 수위관측소 및 청송 수위관측소이다. 기법별 모형평가지표(NSE, PBIAS, RSR), 기저유출지표, 홍수 수문곡선으로부터 분리된 기저유량의 형상을 검토하여 기저유출 분리 결과의 적절성을 평가하였다. FIM, SIM, LMM 기법은 기저유출 분리 시 오류를 일부 포함하고 있는 것으로 분석되었고, 상대적으로 PART 프로그램에 의한 기저유출 분리 결과가 가장 우수한 것으로 나타났다.

A New Query Integrity Verification Method with Cluster-based Data Transformation in Cloud Computing Environment

Miyoung Jang,Min Yoon,Jae-Woo Chang 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.4

Due to advancement in cloud computing technology, the research on the outsourced database has been spotlighted. In database outsourcing, because the service provider might be untrusted or compromised, two issues of data security emerge: data confidentiality and data integrity. Many data transformation schemes were widely studied for preserving data confidentiality, but they are vulnerable to data leakage problem because they do not consider data distribution when encrypting original data. Meanwhile, several query authentication schemes were proposed to verity data integrity, but they suffer from transmission overhead of verification data. Motivated by these problems, we propose a privacy-aware query authentication scheme which guarantees the data confidentiality and the query result integrity of sensitive data. To solve the original data leakage problem, our clustering-based data transformation scheme is designed to select anchors based on data distribution. To verify the query result, we propose a query result authentication index that stores an encrypted signature for each anchor, which is a concatenated hash digest of cluster data. A user compares the verification information with the cluster signatures stored in the verification index. Through performance evaluation, we show that our method outperforms the existing method in terms of query processing time and verification data size.

Efficient Mining of Interesting Patterns in Large Biological Sequences

Rashid, Md. Mamunur,Karim, Md. Rezaul,Jeong, Byeong-Soo,Choi, Ho-Jin Korea Genome Organization 2012 Genomics & informatics Vol.10 No.1

Pattern discovery in biological sequences (e.g., DNA sequences) is one of the most challenging tasks in computational biology and bioinformatics. So far, in most approaches, the number of occurrences is a major measure of determining whether a pattern is interesting or not. In computational biology, however, a pattern that is not frequent may still be considered very informative if its actual support frequency exceeds the prior expectation by a large margin. In this paper, we propose a new interesting measure that can provide meaningful biological information. We also propose an efficient index-based method for mining such interesting patterns. Experimental results show that our approach can find interesting patterns within an acceptable computation time.

Efficient Mining of Interesting Patterns in Large Biological Sequences

Md. Mamunur Rashid,최호진,Md. Rezaul Karim,정병수 한국유전체학회 2012 Genomics & informatics Vol.10 No.1

Pattern discovery in biological sequences (e.g., DNA sequences)is one of the most challenging tasks in computational biology and bioinformatics. So far, in most approaches, the number of occurrences is a major measure of determining whether a pattern is interesting or not. In computational biology, however, a pattern that is not frequent may still be considered very informative if its actual support frequency exceeds the prior expectation by a large margin. In this paper, we propose a new interesting measure that can provide meaningful biological information. We also propose an efficient index-based method for mining such interesting patterns. Experimental results show that our approach can find interesting patterns within an acceptable computation time.