예약기반 장기수행 변동처리를위한 비용인지 시간계획

림청 ( Lin Qing ),팜폭헝 ( Pham Phuoc Hung ),변정용 ( Jeong Yong Byun ) 한국정보처리학회 2011 한국정보처리학회 학술대회논문집 Vol.18 No.2

Web Service technologies make the automation of business activities that are distributed across multiple enterprises possible. Existing extended transaction protocols typically resort to compensation actions to regain atomicity and consistency. A reservation-based transaction protocol is proposed to reduce high compensation risk. However, for a serial long running transaction processing, the resource that is reserved in the early stage may be released due to resource holding time expires. Therefore, our analysis theoretically illustrates a scheduling scheme that tries to prevent the loss of resource holding as well as gain an optimized execution plan with minimum compensation cost. In order to estimate cost of different schedules, we set up a costing model and cost metric to quantize compensation risk.

시간 요구 웹서비스 트랜잭션을 위한 예약기반 규약

림청 ( Lin Qing ),아지즈나스리디노프 ( Aziz Nasridinov ),변정용 ( Jeongyong Byun ) 한국정보처리학회 2010 한국정보처리학회 학술대회논문집 Vol.17 No.2

Business transactional process is usually long running computation which requests services from multiple enterprises. Web Services Transaction specification (WS-TX) defines a protocol, WSBusinessActivity which is specifically designed for such lengthy interaction and maintains overall consistency through compensation. However timely web services transaction is prone to compensate due to tasks’ missing deadline. Therefore, this paper proposes a reservation-based protocol which is used to select providers who can provide resources promptly and deselect ones who may fail. And this selection happens during resource reservation phase and before real commitment. In this way, we achieve the goal of minimizing transactions’ compensation. Finally, we design the framework architecture for the proposed protocol that is extended from WS-BusinessActivity.

WS -트랜잭션의 확장된 적시적 장기수행 트랜잭션 관리 전략

림청 ( Lin Qing ),아지즈나스리디노프 ( Aziz Nasridinov ),변정용 ( Jeongyong Byun ) 한국정보처리학회 2011 한국정보처리학회 학술대회논문집 Vol.18 No.1

Timely management is an important activity in long running transactions. This can be seen in many Supply Chain scenarios where insufficient time management could lead to expensive compensations. Therefore, effective strategy for timely management in long running transactions is needed. In this paper, we propose our solution to detect and avoid violating deadline based on a comparison strategy of predicted complete time and required deadline. Three approaches are used. Firstly, we build Open Nested Transaction Model (ONTM) where deadline of top-level transactions are managed through a flexible time adjustment of lower level transactions. Secondly, workflow is introduced to WS-Transaction framework which supports the algorithm to predict complete time and spot delaying activities. Thirdly, a rule-based coordinator is developed to decide the confirmation or cancelation of participants’ ongoing activities. We also discuss a workflow example for implementation.

Vision-based Walking Guidance System Using Top-view Transform and Beam-ray Model

림청(Qing Lin),한영준(Young-Joon Han),한헌수(Hern-Soo Hahn) 한국컴퓨터정보학회 2011 韓國컴퓨터情報學會論文誌 Vol.16 No.12

본 논문은 야외 환경에서 하나의 카메라를 이용한 시각 장애인을 위한 보행 안내 시스템을 제안한다. 기존의 스테레오 비전을 이용한 보행 지원 시스템과는 다르게 제안된 시스템은 사용자의 허리에 고정된 하나의 카메라를 이용하여 꼭 필요한 정보만을 얻는 것을 목표로 하는 시스템이다. 제안하는 시스템은 먼저 탑-뷰 영상을 생성하고, 생성된 탑-뷰 영상 내 지역적인 코너 극점을 검출한다. 검출된 극점에서 방사형의 히스토그램을 분석하여 장애물을 검출한다. 그리고 사용자 움직임은 사용자에 가까운 지역 안에서 옵티컬 플로우를 사용하여 추정한다. 이렇게 영상으로부터 추출된 정보들을 기반으로 음성 메시지 생성 모듈은 보행 지시 정보를 합성된 음성을 통해 시각 장애인에게 전달한다. 다양한실험 영상들을 사용하여 제안한 보행 안내 시스템이 일반 인도에서 유용한 안내 지시를 제공하는 것이 가능함을 보인다. This paper presents a walking guidance system for blind pedestrians in an outdoor environment using just one single camera. Unlike many existing travel-aid systems that rely on stereo-vision, the proposed system aims to get necessary information of the road environment by using just single camera fixed at the belly of the user. To achieve this goal, a top-view image of the road is used, on which obstacles are detected by first extracting local extreme points and then verified by the polar edge histogram. Meanwhile, user motion is estimated by using optical flow in an area close to the user. Based on these information extracted from image domain, an audio message generation scheme is proposed to deliver guidance instructions via synthetic voice to the blind user. Experiments with several sidewalk video-clips show that the proposed walking guidance system is able to provide useful guidance instructions under certain sidewalk environments.

Lane Detection in Complex Environment Using Grid-Based Morphology and Directional Edge-link Pairs

림청(Qing Lin),한영준(Young-Joon Han),한헌수(Hern-Soo Hahn) 한국지능시스템학회 2010 한국지능시스템학회논문지 Vol.20 No.6

본 논문은 복잡한 도로 환경에서 차선을 정확하게 찾는 실시간 차선 검출법을 보인다. 기존의 많은 방법들은 대게 후처리 과정에서 차선 안쪽에 존재하는 잡음을 찾아 차선의 위치를 찾지만, 제안하는 방법은 특징 추출 단계에서 가능한 많은 잡음을 제거하므로 후처리 과정에서 검색 영역을 최소화한다. grid기반 모폴로지 연산은 우선 관심영역을 능동적으로 생성한 후, 모폴로지의 닫기 연산을 통해 에지 들을 연결한다. 그리고 방향성 에지 연결 기법을 통하여 유효한 방향에지를 찾고 사전에 구해진 영상 내 차선의 높이와 두 차선 간의 폭 관계를 이용하여 두 개의 차선을 군집화한다. 마지막으로 차선의 색상은 YUV색상 공간에서 두 개의 연결된 에지 안쪽을 검사하여 Bayesian확률 모델을 사용하여 추정한다. 제안하는 방법의 실험 결과는 다수의 불필요한 에지 군집이 존재하는 복잡한 도로 환경에서 효과적으로 도로 에지를 감별하였으며, 제안하는 알고리즘은 해상도 320×240 영상으로 10ms/frame의 속도에서 약92%의 정확도를 보였다. This paper presents a real-time lane detection method which can accurately find the lane-mark boundaries in complex road environment. Unlike many existing methods that pay much attention on the post-processing stage to fit lane-mark position among a great deal of outliers, the proposed method aims at removing those outliers as much as possible at feature extraction stage, so that the searching space at post-processing stage can be greatly reduced. To achieve this goal, a grid-based morphology operation is firstly used to generate the regions of interest (ROI) dynamically, in which a directional edge-linking algorithm with directional edge-gap closing is proposed to link edge-pixels into edge-links which lie in the valid directions, these directional edge-links are then grouped into pairs by checking the valid lane-mark width at certain height of the image. Finally, lane-mark colors are checked inside edge-link pairs in the YUV color space, and lane-mark types are estimated employing a Bayesian probability model. Experimental results show that the proposed method is effective in identifying lane-mark edges among heavy clutter edges in complex road environment, and the whole algorithm can achieve an accuracy rate around 92% at an average speed of 10ms/frame at the image size of 320×240.

An Improved Reservation-based Protocol for Timely Web Service Transactions

림청(Lin Qing),아지즈 나스리디노프(Aziz Nasridinov),밤복흥(Pham Phuoc Hung),변정용(Jeong Yong Byun) 한국정보과학회 2011 정보과학회 컴퓨팅의 실제 논문지 Vol.17 No.8

웹서비스 트랜잭션은 다원분산 기업간 장기수행, 완결합 그리고 복합서비스들로 구성되어 있다. 기존 트랜잭션 규약은 보상을 통하나 바람직하잖은 비용으로 전체적으로 일관성을 유지한다. 따라서 기존 연구들은 자원 대기시간 및 보상 위기를 줄이기 위하여 자원을 보존하도록 제안했었다. 반면에 예약은 또한 실질적인 잠금과 수행성능을 개선하는 병행충돌들을 가져온다. 본 논문에서 개선된 시간제약으로 예약기반규약을 제안한다. 그리고 측면효과를 없애는 것을 돕는다. 또한 병행충돌 탐지가 성능을 높이기 위하여 개발된다. 더구나 시물레이션은 이 자원중심적 접근을 SOA로 통합한다. 결국 적시적 웹서비스 트랜잭션용 성능평가는 성공율, 실행기간, 보상비용 관점에서 커다란 개선을 보여준다. Web Service Transactions consist of long-running, loosely coupled and complex services across multiple distributed enterprises. Existing transaction protocols maintain overall consistency through compensation but with undesirable cost. Thus, researchers have proposed to reserve resources to reduce resource waiting time and compensation risk. Meanwhile, reservation also brings substantial locks and concurrent conflicts that impair performance. In this paper, we propose a reservation-based protocol but with an imposed time constraint, which helps eliminate those side effects. Also, concurrent conflicts detection is developed as well to enhance performance. Moreover, the simulation integrates this resource-centric approach into Service-Oriented Architecture (SOA). Finally, performance evaluation for timely Web Service Transaction shows a great improvement in aspects of success rate, execution duration and compensation cost.

웹서비스 보안에서 솦공격에 대한 관대한 계획

밤복흥 ( Pham Phuoc Hung ),아지즈나스리디노프 ( Aziz Nasridinov ),림청 ( Lin Qing ),변정용 ( Jeongyong Byun ) 한국정보처리학회 2011 한국정보처리학회 학술대회논문집 Vol.18 No.2

Nowadays Web Services are one of the most rapidly developed technologies and have become platform for eecommerce as well as B2B model. Therefore, when Web Services use SOAP as a protocol for communication, their security should be considered. However, those SOAP messages are prone to XML attacks that can create a foundation for typical faults and make it vulnerable to use. Unfortunately, recent researches established that solutions to deal with these problems have several limitations. In this paper, we explore attacks on SOAP messages and also provide confidentiality and integrity solutions. It is a tolerant scheme which is able to automatically detect and fix typical faults occurred in SOAP messages to combat with the security threats in order to improve its reliability.