• 대기
• /
• 제29권5호
• /
• pp.615-626
• /
• 2019

To find any effects of precipitation climate on the forecast verification methods, we processed the hourly records of precipitation over South Korea. We examined their relationship between the climate and the methods of verification. Precipitation is an intermittent process in South Korea, generally less than an hour or so. Percentile ratio of precipitation period against the entire period of the records is only 14% in the hourly amounts of precipitation. The value of the forecast verification indices heavily depends on the climate of rainfall. The direct comparison of the index values might force us to have a mistaken appraisal on the level of the forecast capability of a weather forecast center. The size of the samples for verification is not crucial as long as it is large enough to satisfy statistical stability. Our conclusion is still temporal rather than conclusive. We may need the amount of precipitation per minute for the confirmation of the present results.

• Steel and Composite Structures
• /
• 제16권1호
• /
• pp.45-58
• /
• 2014

EC3 provides several methodologies for the stability verification of members and frames. However, when dealing with the verification of non-uniform members in general, with tapered cross-section, irregular distribution of restraints, non-linear axis, castellated, etc., several difficulties are noted. Because there are yet no guidelines to overcome any of these issues, safety verification is conservative. In recent research from the authors of this paper, an Ayrton-Perry based procedure was proposed for the flexural buckling verification of web-tapered columns. However, in order to apply this procedure, Linear Buckling Analysis (LBA) of the tapered column must be performed for determination of the critical load. Because tapered members should lead to efficient structural solutions, it is therefore of major importance to provide simple and accurate formula for determination of the critical axial force of tapered columns. In this paper, firstly, the fourth order differential equation for non-uniform columns is derived. For the particular case of simply supported web-tapered columns subject to in-plane buckling, the Rayleigh-Ritz method is applied. Finally, and followed by a numerical parametric study, a formula for determination of the critical axial force of simply supported linearly web-tapered columns buckling in plane is proposed leading to differences up to 8% relatively to the LBA model.

• 대한수학회보
• /
• 제46권2호
• /
• pp.199-207
• /
• 2009

This note is a verification on the relations between almost linear and nearly additive maps; and the continuity of almost multiplicative nearly additive maps. Also we consider the stability of nearly additive and almost linear maps.

• 한국항공우주학회지
• /
• 제42권12호
• /
• pp.1051-1056
• /
• 2014

소형인공위성에 적용을 목적으로 전기추진시스템의 연료공급부가 개발되었다. 연료공급부는 연료로 사용되는 제논을 높은 압력과 밀도의 가스상태로 저장하게 된다. 제논은 상온에서 임계점을 갖는데 발사환경에서 과도상태로 시스템에 영향을 미칠 수 있다. 따라서 발사환경에 대한 본 시스템의 기능적 구조적 안정성은 지상시험을 통한 검증이 필요하다. 본문에서는 연료공급부의 설계점과 검증시험내용을 논하고 시험결과를 정리하였다. 검증시험을 통해 본 시스템이 발사환경에 대하여 안정성을 확보하고 있는 것을 확인하였다.

• 융합보안논문지
• /
• 제12권1호
• /
• pp.27-33
• /
• 2012

VANET(Vehicular Ad-hoc Network)은 지능형 차량들로 이루어진 애드혹 네트워크 환경으로서 최근 들어 그 연구가 활발하게 진행되고 있는 분야이다. VANET은 원활한 교통 소통, 사고 방지 등 여러 가지 편리한 기능들을 제공하지만 그 기반을 애드혹 네트워크에 두고 있기 때문에 애드혹 망에서 발생하는 보안 문제를 가지고 있고 또한 그 환경적 특성에 따라 추가적인 보안 요구 사항이 존재한다. 본 논문에서는 해쉬함수를 이용한 기존의 V2I 인증프로토콜에 대하여 검토하고, 이를 정형적 검증 방법인 Casper를 이용하여 인증 프로토콜의 안정성을 분석하였고 그 결과 안전함을 증명하였다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2022년도 추계학술대회
• /
• pp.43-46
• /
• 2022

수용가에서 사용되는 수돗물의 패턴과 양을 정확하게 예측하여 필요한 만큼의 수돗물을 펌프를 이용하여 배수지로 전달하여 저장하고, 필요한 유량이 최소의 전기에너지를 이용하여 적기에 공급되어야 정수장의 최적화 운영을 할 수 있다. 본 논문에서는 수돗물 생산·공급의 안정성을 확보하기 위하여 AI 기반 복합센서를 실증지인 정수장에 적용하기 전에 사전검증할 수 있는 시스템을 구축하여 복합센서별 사전검증 모델을 통해 보완 사항을 도출하고, 제작 과정에 피드백하여 복합 센서 데이터의 품질 및 동작 안정성을 향상시키고자 하였다.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
• /
• pp.131-134
• /
• 2002

As the increased use of computer, wired/wireless/mobile Internet, security in using Internet becomes a more important problem. Thus, biometric technology using physical and behavior characteristics of a person is hot issue. Many different types of biometric technologies of a person such as fingerprint, face, iris, vein, DNA, brain wave, palm, voice, dynamic signature, etc. had already been studied but remained unsuccessful because they do not meet social demands. However, recently many of these technologies have been actively revived and researchers have developed new products on various commercial fields. Dynamic signature verification technology is to verify the signer by calculating his writing manner, speed, angle, and the number of strokes, order, the down/up/movement of pen when the signer input his signature with an electronic pen for his authentication. Then signature verification system collects mentioned above various feature information and compares it with the original one and simultaneously analyzes to decide whether signature is forgery or true. The prospect of signature verification technology is very promising and its use will be wide spread in terms of economy, security, practicality, stability and convenience.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.960-964
• /
• 2004

During system resource improvement process that based on Object-Oriented technology could be affect to the continuous system performance if lack appropriate management and control objects mechanism. This paper proposes a methodology to support continuous system performance and its stability. The adoption is based on Java Container Framework and Collections Framework for object collection. Also includes Software Engineering, Object Migration and Multiple Class Loaders mechanism accommodate to construct Continuous Migration Container (CMC). CMC is a runtime environment provides interfaces for management and control to support upgrading object process. Upgrade object methodology of CMC can be divided into two phase are object equivalence checking and object migration process. Object equivalence checking include object behavior verification and functional conformance verification before object migration process. In addition, CMC use Multiple Class Loaders mechanism to support reload effected classes instead of state transfer in migration process while upgrading object. These operations are crucial for system stability and enhancement efficiency.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2011년도 학술발표회
• /
• pp.337-340
• /
• 2011

In this study, qualitative and quantitative evaluations are performed using the hydraulic analysis of fiber stone for bridge pier scour protection. We can consider that the effective scour protection should be suggested from the side of hydraulic stability, structure stability, and permissible tractive force. The perfect verification, however, on the fiber stone for bridge pier scour protection is not sufficient because of short literatures and experiments on the field study. The continuous research, therefore, will be needed to establish reliable verification using literatures investigation and the various experiments on the fiber stone for bridge pier scour protection.

• 한국소음진동공학회논문집
• /
• 제11권6호
• /
• pp.208-215
• /
• 2001

The paper presents both theoretical and experimental study fur dynamic instabilities of a vortical cantilevered pipe with two attached lumped masses conveying fluid. The two attached lumped masses can be considered as valves or some mechanical paras in real pipe systems. Eigenvalue behaviors depending on the flow velocity are investigated for the change of Positions and magnitudes of an attached lumped mass and a tip mass. In order to verify appropriate of numerical solutions, experiments were accomplished. Theoretical predictions have a good agreement with experimental ones.