권영만 노스웨스턴대학교 건설 및 환경공학과 박사후 연구원

권영만 한국지반공학회 2024 지반 : 한국지반공학회지 Vol.40 No.2

시냇가교회 사례발표 : 가족 같은 교회 공동체 세우기

권영만 총체적복음사역연구소 2015 총체적 복음사역의 신학과 실천 : 총체적복음사역연구소 연구지 Vol.11 No.-

화일 시스템의 저장 장치 관리 기법에 관한 연구

권영만 서울保健大學 1994 論文集 Vol.14 No.1

Next-generation workstations will have hardware support for digital continuous media (CM) such as audio and video. CM application handle data at high rates, with strict timing requirements, and often in small chunks. If such applications are to run efficiently and predictably as user-level programs, an operating system must provide efficient file system, scheduling and IPC mechanisms that reflect these needs. The storage devices offer huge storage capacity at a low cost per byte, but with large access times. Disk technology is improving rapidly, but the improvements have been primarily in the area of cost and capacity rather than performance. So in this paper, we will survey the several mechanism to improve the performance in term of access time. These are the traditional UNIX file system, fast file system, log-structed file system, logical disk, and file system for digital audio/video. This study is necessary for supporting continuous media even though we will get more fast disk.

멀티미디어를 위한 입출력 시스템 개선에 관한 연구

권영만 서울保健大學 1996 論文集 Vol.16 No.1

Next-generation workstation will have hardware support for multimedia data such as digital audio and video, Traditional I/O system relies on the data copy mechanism. This makes the speed gap between CPU and memory wider and does not support I/O-intensive applications well because they cannot transfer data efficiently, Therefore next-generation operating system needs new I/O system for mutimedia data, This work is to survey and classify the several mechanism to improve the I/O system for multimedia data. Most mechanism eliminates copies at one or more points in the I/0 system. These are shared memory I/O, page transfer, direct transfer. kernel stream, device stream mechanisms. Some things make use of the virtual memory, and the others make use of special hard ware features.

경험기법을 사용한 SNS 스팸의 클러스터링에 관한 연구

권영만,이인락,김명관,Kwon, Young-Man,Lee, In-Rak,Kim, Myung-Gwan 한국인터넷방송통신학회 2014 한국인터넷방송통신학회 논문지 Vol.14 No.6

It has good features for social networking with friends SNS is maintained. However, various enterprises, individuals invading the inconvenience spammers have exposure to a number of users to tweet spam. The study was conducted in the existing research on these spam tweets. However, the results showed a more accurate classification and detection is difficult because of the lack of precision and different causes. In this paper, we describe how to classify the characteristics of spammers, classification criteria. Also has a link rate and difference between followers and following, these features were present classification criteria for spammers account. This experiment was performed according to the criteria. Randomized trial of spam and non-spam accounts were selected and account type was conducted according to the criteria 68% of the link ratio of spam accounts. Followers / Following ratio was 27581.5. Non-spam accounts was 6.12%. Followers / Following ratio was 1.26. SNS는 친구들의 친목과 인맥유지를 위한 순기능을 가지고 있다. 그러나 각종 기업, 개인 스패머들이 팔로잉을 통해 스팸 트윗하여 다수의 이용자들에게 노출, 불편을 끼치고 있다. 기존 연구에서 이러한 스팸 트윗에 대해 연구를 실시한경우가 있다. 그러나 정교함의 부족함과 여러 원인들로 인해 보다 정확한 분류 및 검출이 어려운 결과를 나타내었다. 본 논문에서는 스패머들의 특징, 분류기준, 분류방법에 대해 기술하였다. 또한 이러한 특징 중 링크율과 자신을 팔로워한 부류와 자신이 팔로잉한 부류와의 차이를 통하여 스패머 계정에 대한 분류기준을 제시하였다. 실험은 무작위 스팸 계정과 일반 계정을 선정하였으며 분류기준에 따라 진행하였다. 결과로 스팸 계정은 링크율 68%, 팔로워 / 팔로잉 비율은 27581.5 였고 일반 계정은 6.12%, 팔로워 / 팔로잉 비율은 1.26 였다.

원격 프로시져 호출의 구현시의 은폐성 연구

권영만 서울保健大學 1994 論文集 Vol.14 No.1

RPC(Remote Procedure Call) is the most general paradigm to support IPC (Inter-Process Communication) between processes on the different computer which is connected through the computer network. It is used to various areas on distributed system. Therefore, the understanding and design of RPC is very important on the design of distributed system. Although the concept and implementation of RPC is simple, there are many things to implement RPC transparently. Those are client-server binding, RPC semantics, transport protocol to support the transparency which is different with normal procedure call. In this paper. I will survey the concept of RPC and the subtle things in designing it.

Development of Applications for Disaster Safety Management of Traditional Markets

권영만,갈원모 대한설비관리학회 2017 대한설비관리학회지 Vol.22 No.4

While traditional markets have functioned as major trade centers that regulated regional economy in Korea in the past, they have lost their significance and popularity over the last few decades due to the expansion of Internet shopping and development of superstores and convenience stores. With lack of support from the local government, the traditional markets in the Gyeonggi province became outdated and incapable of competing against modern forms of markets. Antiquated facilities as well as insanitary surroundings of traditional markets incapacitated them from retaining their customers, and traditional markets were soon overshadowed by superstores. With close examination of the Sung-ho traditional market, an embryonic traditional market located in Jung-won gu, Sungnam city, this study aims to identify major safety problems of traditional markets. Further, the study will also introduce a smartphone disaster management application to redress those problems.

소형 연 X-선 현미경

권영만,김한경,강성훈,김경우,윤권하 원광대학교 대학원 2008 論文集 Vol.41 No.-

A Soft x-ray microscope operates in the 'water window' wavelength region (2.3-4.4 nm), where natural contrast between carbon (protein) and oxygen (water) allows to image a biological cell. The compact soft x-ray microscope operates at λ = 2.88 nm (430 eV) and consist of liquid-nitrogen-jet-target laser-plasma x-rays source, a tandem ellipsoidal condenser mirror for sample illumination, an objective micro zone plate, and a thinned back-illuminated charge coupled device with 1,024 × 1,024 pixels. The Liquid-nitrogen-jet-target laser-plasma source was a high brightness of 1.4×10^(12) photons/pulse·sr·line. The tandem ellipsoidal condenser mirror has 15% reflectivity. The photon flux arrived at the sample is 1.29×10^(5) photons/μ㎡ The micro zone plate was used for an objective optic, and had outermost zone width of 30 nm, zone number of 667, and diameter of 80㎛, and the focal length was 835㎛. On performance test for the compact soft x-ray microscope, the 'Siemens Star' image was obtained with a 60-nm-resolution at 380 magnification and 3 minutes exposure. I also obtained images of biological samples, such as diatom and red blood cell of a mouse with 5-10 minutes exposure.

DCT를 사용한 디지털 하프토닝

권영만,김규호,권형준 한국인터넷방송통신학회 2013 한국인터넷방송통신학회 논문지 Vol.13 No.6

이 논문에서는 먼저 디지털 하프토닝 영상을 생성하는 기존의 방법들과 DCT 변환에 대해서 설명한다. 그런 후에 DCT 변환에 근간을 둔 새롭고 단순한 하프토닝 알고리즘을 제안한다. 이 논문은 제안한 알고리즘을 검정하기 위해서 실현 가능성 검증을 수행한다. 그래서 DCT 계수의 가중치를 조절하여 생성된 여러 가지 영상들을 평가하였 다. 실험을 통해서 단순한 이상적인 계단 함수 형태의 가중치를 사용하는 것보다는 램프 함수 형태의 가중치를 사용 하면 더 좋은 결과를 얻었다. 단순한 응용분야로서 MPEG 비디오에 제안한 알고리즘을 적용하여 하프토닝 비디오를 생성할 수 있다. In this paper, we discussed the traditional methods of generating digital halftoning image and DCT transform. Then we propose a new and simple halftoning algorithm that is based on DCT transformation. We do the feasibility test to verify the proposed algorithm. So we assessed several images generated by adjusting weights of DCT coefficients. As a result, we got the better result for weights of the ramp function type than for weights of the step function type through experiment. As a simple application, we can apply our algorithm to the MPEG video for generating the halftoning video.

CCD 카메라를 이용한 도로 붕괴 사태 검출 알고리즘

권영만,신세연,박영진,김은수 한국인터넷방송통신학회 2011 한국인터넷방송통신학회 논문지 Vol.11 No.2

논문에서는 CCD 카메라의 영상 즉 비전만을 사용해서 도로사면 붕괴와 같은 도로 사태를 검출하는 효과적인 알고리즘을 제안하였다. 제안한 알고리즘은 영상을 비감시영역과 감시영역으로, 감시 영역은 비도로, 경계, 도로 영역으로 구분한다. 그런 후에 움직임 블록을 정의하고, 생존시간 테이블을 사용해서 움직임의 히스토리를 기억하며, 움직임의 구성요소들이 비도로 영역에서 도로 영역까지 함께 존재하는지를 확인하여 도로 붕괴 사태를 결정하였다. 실험을 통해 제안한 알고리즘이 효과적으로 도로 사태를 검출하는 것을 확인하였다. In this paper, we proposed the vision-based efficient algorithm for road slide detection like as destruction of road cut slope. The proposed algorithm defines the image region as non surveillance and surveillance which is further divided by road, boundary and non road region. After that, it find the moving block, remember the history of movement using the TTL(Time To Live) table, determine the road slide by checking the existence of moving blocks from non road region to road region together. We confirmed the proposed algorithm detected the road slide effectively through experiments.