• 한국정보통신학회논문지
• /
• 제10권8호
• /
• pp.1435-1442
• /
• 2006

안전성에 대한 이상적인 평가방법은 운영체제내의 모든 가능한 연산을 대상으로 실행 결과의 안정성 여부를 검사하는 것이다. 하지만 이는 현실적으로 불가능하다. 그러나 정형기법을 사용할 경우 운영체제 동작논리상의 안전성 보장 여부를 이론적으로 증명할 수 있다. 따라서 본 논문에서는 보안커널의 안정성 검증방법에 대하여 논하고, 정형검증의 대표적인 도구들에 대하여 비교분석을 수행하였다. 그리고 보안커널에 기반한 다중레벨 접근통제모델인 수정된 BLP(Bell & LaPadula) 모델을 검증하기에 적합한 PVS(Prototype Verification System) 검증도구를 선정하였다. 마지막으로 PVS 검증도구를 활용하여 정형명세를 작성하고, 작성된 정형명세의 검증을 통하여 수정된 BLP 모델이 안전한 보안모델이라는 것을 검증하였다.

• 한국멀티미디어학회논문지
• /
• 제9권12호
• /
• pp.1607-1616
• /
• 2006

The growing market of multimedia and digital signal processing requires significant data-path portions of SoCs. However, the common models for verification are not suitable for SoCs. A novel model--WGL (Weighted Generalized List) is proposed, which is based on the general-list decomposition of polynomials, with three different weights and manipulation rules introduced to effect node sharing and the canonicity. Timing parameters and operations on them are also considered. Examples show the word-level WGL is the only model to linearly represent the common word-level functions and the bit-level WGL is especially suitable for arithmetic intensive circuits. The model is proved to be a uniform and efficient model for both bit-level and word-level functions. Then Based on the WGL model, a backward-construction logic-verification approach is presented, which reduces time and space complexity for multipliers to polynomial complexity(time complexity is less than $O(n^{3.6})$ and space complexity is less than $O(n^{1.5})$) without hierarchical partitioning. Finally, a construction methodology of word-level polynomials is also presented in order to implement complex high-level verification, which combines order computation and coefficient solving, and adopts an efficient backward approach. The construction complexity is much less than the existing ones, e.g. the construction time for multipliers grows at the power of less than 1.6 in the size of the input word without increasing the maximal space required. The WGL model and the verification methods based on WGL show their theoretical and applicable significance in SoC design.

• 한국수자원학회논문집
• /
• 제39권3호
• /
• pp.215-226
• /
• 2006

본 연구에서는 경안천 유역에 대해 초단시간 강수예보모델인 VSRF(Very Short Range Forecast of precipitation) 모델에서 생산되는 예측강우량의 검증을 실시하고, 이를 NWSPC(National Weather Service PC) 강우-유출 모형에 적용하였다. 강수는 기상학적 검증과 수문학적 검증으로 구분하여 검증하였다. 기상학적 검증은 유역 내에 존재하는 AWS 강수량과 VSRF모델 강수량의 정성적 관계를 객관적으로 제시하였고, 수문학적 검증은 AWS 면적 가중치를 고려한 유역평균 강우량과 VSRF유역평균 강우량과의 정량적 검증결과를 제시하였다. 또한 예보모델에서 생산된 6시간 예측강수량을 NWSPC 모형에 적용해 강수예보모델의 수문연계 가능성을 검토해 본 결과 0.6 이상의 높은 상관관계를 보여 예보모델의 수자원 활용 가능성을 제시하였다.

• ETRI Journal
• /
• 제33권3호
• /
• pp.423-433
• /
• 2011

This paper introduces an adaptive and integrated utterance verification (UV) framework using minimum verification error (MVE) training as a new set of solutions suitable for real applications. UV is traditionally considered an add-on procedure to automatic speech recognition (ASR) and thus treated separately from the ASR system model design. This traditional two-stage approach often fails to cope with a wide range of variations, such as a new speaker or a new environment which is not matched with the original speaker population or the original acoustic environment that the ASR system is trained on. In this paper, we propose an integrated solution to enhance the overall UV system performance in such real applications. The integration is accomplished by adapting and merging the target model for UV with the acoustic model for ASR based on the common MVE principle at each iteration in the recognition stage. The proposed iterative procedure for UV model adaptation also involves revision of the data segmentation and the decoded hypotheses. Under this new framework, remarkable enhancement in not only recognition performance, but also verification performance has been obtained.

• 대기
• /
• 제27권2호
• /
• pp.235-249
• /
• 2017

This paper describes methodology verifying near-surface predictability of numerical weather prediction models against the surface synoptic weather station network (SYNOP) observation. As verification variables, temperature, wind, humidity-related variables, total cloud cover, and surface pressure are included in this tool. Quality controlled SYNOP observation through the pre-processing for data assimilation is used. To consider the difference of topographic height between observation and model grid points, vertical inter/extrapolation is applied for temperature, humidity, and surface pressure verification. This verification algorithm is applied for verifying medium-range forecasts by a global forecasting model developed by Korea Institute of Atmospheric Prediction Systems to measure the near-surface predictability of the model and to evaluate the capability of the developed verification tool. It is found that the verification of near-surface prediction against SYNOP observation shows consistency with verification of upper atmosphere against global radiosonde observation, suggesting reliability of those data and demonstrating importance of verification against in-situ measurement as well. Although verifying modeled total cloud cover with observation might have limitation due to the different definition between the model and observation, it is also capable to diagnose the relative bias of model predictability such as a regional reliability and diurnal evolution of the bias.

• 대한음성학회지:말소리
• /
• 제49호
• /
• pp.145-158
• /
• 2004

This paper is aiming at implementation of real-time speaker verification system using DSP board. Dialog/4, which is based on microprocessor and DSP processor, is selected to easily control telephone signals and to process audio/voice signals. Speaker verification system performs signal processing and feature extraction after receiving voice and its ID. Then through computing the likelihood ratio of claimed speaker model to the background model, it makes real-time decision on acceptance or rejection. For the verification experiments, total 15 speaker models and 6 background models are adopted. The experimental results show that verification accuracy rates are 99.5% for using telephone speech-based speaker models.

• 시스템엔지니어링학술지
• /
• 제2권2호
• /
• pp.33-38
• /
• 2006

It is well known that efficient management and thorough implementation of stakeholder requirements is vital for a successful development of a large-scale and complex system. Equally important is to make sure that all the requirements be correctly realized in the developed system. For the purpose, verification requirements are derived with traceability from the system requirements. This paper discusses a step by step process for constructing the requirements verification model which includes : 1) the schema modeling both requirements and their traceability; 2) the template documenting the verification requirements; 3) the verification model constructed from the schema; and 4) the test and evaluation plan that can be printed automatically.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
• /
• pp.281-284
• /
• 2004

In this paper, a verification method and model for a PCI-Express device are described. PCI-Express technology is one of new I/O interconnection technologies which is intended to replace conventional PCI based technology, and is introduced by PCI-SIG in 2002. For a fast prototyping, a verification suite which includes a behavioral model and stimuli is needed before actual design is finished. And also it should be simple in structure and accurate enough to verify the design. In this paper, an Early Verification Suite (EVS) which complies with PCI-Express protocol is developed and tested.

• ETRI Journal
• /
• 제33권6호
• /
• pp.914-923
• /
• 2011

This paper concerns robust and reliable speaker model training for text-independent speaker verification. The baseline speaker modeling approach is the Gaussian mixture model (GMM). In text-independent speaker verification, the amount of speech data may be different for speakers. However, we still wish the modeling approach to perform equally well for all speakers. Besides, the modeling technique must be least vulnerable against unseen data. A traditional approach for GMM training is expectation maximization (EM) method, which is known for its overfitting problem and its weakness in handling insufficient training data. To tackle these problems, variational approximation is proposed. Variational approaches are known to be robust against overtraining and data insufficiency. We evaluated the proposed approach on two different databases, namely KING and TFarsdat. The experiments show that the proposed approach improves the performance on TFarsdat and KING databases by 0.56% and 4.81%, respectively. Also, the experiments show that the variationally optimized GMM is more robust against noise and the verification error rate in noisy environments for TFarsdat dataset decreases by 1.52%.

• 한국ITS학회 논문지
• /
• 제11권5호
• /
• pp.62-69
• /
• 2012

교통 시뮬레이션 모형은 실제 교통 네트워크를 모형으로 구현하여 여러 가지 교통정책을 평가하는 데에 사용된다. 이때 모형이 실제의 교통현상을 잘 반영했는지 여부를 판단하는 모형 검증 절차는 가장 중요한 절차 중 하나이며 모형 검증에는 실측 교통량과 속도 등이 주로 사용된다. 본 연구에서는 노스캐롤라이나 랄리에 있는 I-40 고속도로 상에서 일어나는 심각한 오후 첨두 병목현상을 DYNASMART-P라는 메조스코픽 교통 시뮬레이션 모형으로 구현한 결과를 검증하고자 하였다. 연구 대상 축의 경우 노스캐롤라이나 교통국(NCDOT)의 교통정보센타에서 속도검지기를 설치하여 온라인으로 속도를 수집하고 있다. 그러나 검지기 측정 자료는 지점속도이고 시뮬레이션 모형의 결과값은 링크 평균속도이므로 모형 검증에 사용하기에는 적합하지 않다. 따라서, 본 연구에서는 GPS 장비를 활용하여 통행시간을 측정하여 모형에서의 통행시간과 비교함으로써 시뮬레이션 모형의 결과를 검증하였다. 이 논문에서는 데이터 수집, 모형검증 절차 및 결과를 서술하였다.