• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.189-192
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• 2008

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.85-88
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• 2003

• Journal of Broadcast Engineering
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• v.22 no.6
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• pp.774-784
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• 2017

Occupancy sensors installed in buildings and households turn off the light if the space is vacant. Currently PIR (pyroelectric infra-red) motion sensors have been utilized. Recently, the researches using camera sensors have been carried out in order to overcome the demerit of PIR that can not detect static people. If the tradeoff of cost and performance is satisfied, the camera sensors are expected to replace the current PIRs. In this paper, we propose vision sensor-based occupancy detection being composed of tracking, recognition and detection. Our softeware is designed to meet the real-time processing. In experiments, 14.5fps is achieved at 15fps USB input. Also, the detection accuracy reached 82.0%.

• Journal of Korean Society of Transportation
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• v.34 no.2
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• pp.168-179
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• 2016

This study describes an improved model for estimating pedestrian LOS (Level of Service) by utilizing the space occupied by pedestrians. The method introduced the concept of conflict along the bi-directional pedestrian flow which enables calculating conflict area and average travel time in walking. Especially, the method incorporates the idea of generalized density concept which can consider effective walking area and pedestrian flow rates that might vary during the analysis period. After establishing methodology, adjustments of pedestrian LOS criteria in term of walking space occupied by pedestrians were performed. As a result, walking-occupied space at capacity level is 0.68 and corresponding pedestrian flow rate was calculated as 80 persons/min/m, while different pedestrian-occupied spaces were ordered to classify LOS at the points where the gradient changes. Furthermore, the statistical verification of service levels has shown that there is significant difference among all LOS categories at 5% significance level.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.11
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• pp.2437-2445
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• 2012

This paper presents the efficient measurement method of radio resource by analyzing various medium occupied elements. The medium occupied time consists of 802.11 frames, wireless interference, and protocol waiting time from a wireless node on a current channel. And it is used to performance metric. Existing research is only measured partial occupied elements, and is lack of validation of measurement unit and scalability on various IEEE 802.11 radio. This paper presents the measurement method of classified occupied elements. To achieve this, we modified 802.11n based OpenHAL device driver to collect the register information of wireless chipset, and to analyze receiving frames in an virtual monitor mode. We conclude accurate medium occupied time measurement system from various validation methods.

• Proceedings of the KGS Conference
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• 2003.05a
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• pp.148-151
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• 2003

인간은 일찍이 지표상에서 하천, 동굴, 구릉 및 산록 등에 다양한 거주 공간을 형성하여 왔다. 물론 이러한 공간의 점유는 단순한 의미만을 가지는 것은 아니다. 식량 구득을 위하여 경지가 필요하였고, 그렇지 못한 장소는 잉여 물자의 물물교환이 이루어지면서 장소를 점유하게 되었다. 하천이나 바다에 의해 분리된 지역 간의 교류는 배라는 교통수단이 필수적이다. (중략)

• Journal of IKEEE
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• v.9 no.2 s.17
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• pp.123-135
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• 2005

3GPP RLC protocol specification adopted a window-controlled selective-repeat ARQ scheme for provisioning reliable data transmission. Inevitably, the re-ordering issue arises in the 3GPP's ARQ since it belongs to the selective-repeat ARQ clan. A long re-ordering time results in the degradation of throughput and delay performance, and may invoke the overflow of the re-ordering buffer. Also, the re-ordering time must be regulated to meet the requirements of some services which are both loss-sensitive and delay-sensitive. In the 3GPP's ARQ, we may deflate the occupancy of the re-ordering buffer by reducing the window size and/or length of the status report period. Such a decrease, however, deteriorates the throughput and delay performance and encroaches the resource of the reverse channel. Aiming at reducing the occupancy at the re-ordering buffer while suppressing the degradation of throughput and delay performance, we propose threshold-dependent occupancy control schemes, identified as post-threshold and pre-threshold schemes, as supplements to the 3GPP's ARQ. For judging the effectiveness of the proposed schemes, we investigate peak occupancy, maximum throughput and average delay in the practical environment involving fading channels. From the simulation results, we observe that the proposed schemes invoke the performance trade-off between occupancy and throughput in general. Also, we reveal that the post-threshold scheme is able to improve the throughput and delay performance of the ordinary 3GPP's ARQ without inflating the occupancy of the re-ordering buffer.

• Korea Petroleum Association Journal
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• no.7 s.249
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• pp.66-76
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• 2005

●2004년 세계 석유 소비는 8천75만7천 b/d로 전년대비 3.4% 증가하여 1978년 이래 최고상승률을 기록했다. 소비 비중은 미국이 전체의 24.9%를 점유하여 1위를 차지했고 중국(8.2%), 일본(6.4%), 러시아연방(3.4%), 독일(3.3%), 인도(3.2%), 한국(2.8%)순으로 나타났다. ●석유소비증가량은 중국이 전년대비 무려 15.8%인 246만 3천b/d증가하였고 미국은 2.8%인 48만 4천 b/d 증가한 반면 일본은 3.0%인 16만 7천 b/d감소하는 등 전체적으로 246만 7천 b/d증가하였다. ●세계석유생산은 8천 26만 b/d로 전년대비 4.5% 증가하였고 생산량 순으로는 사우디아리비아가 전체의 13.1%를 점유하여 1위를 차지하였고, 러시아연방(11.9%), 미국(8.5%), 이란(5.2%), 멕시코(4.9%), 중국(4.5%) 순으로 나타났다. ●세계석유매장량은 1조 1,886억 배럴로 가채년수는 405년이며 국가별로는 사우디아라비아가 전체의 22.1%를 점유하여 1위를 차지하였고 이란(11.1%), 이라크(9.7%), 쿠웨이트(8.3%), UAE(8.2%), 베네수엘라(6.5%), 러시아연방(6.1%) 순으로 나타났다. ●세계정제능력은 8천 459만 2천b/d로 전년대비 0.8% 증가하였다. 국가별로는 미국이 전체의 20.1%를 점유하여 1위를 차지하였고 중국(6.9%), 러시아연방(6.4%), 일본(5.4%), 한국(3.1%) 순으로 나타났다.

• Land and Housing Review
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• v.4 no.4
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• pp.395-406
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• 2013

The purpose of this paper is to analyze of the home energy consumption and conservation awareness, usage patterns and policy directions for housing energy-saving house by three types of houses tenure. The results of analysis is : First, there is existed to the difference in average by each housing tenure types. Second, the residents of sales apartment and tenants of private and public rental apartment are practices in the energy consumption and conservation Third, the behavior between residents of sale-housing and the tenants of private and rental housing on the energy-saving behavior items is existed with behavioral differences. Finally, the consumer-oriented incentives method in the future housing energy' policy direction might be used more efficient and effective than others

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.257-260
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• 2022

국제표준 3차원 포인트 클라우드 압축 기술인 MPEG(Moving Picture Experts Group)-I(Immersive) V-PCC(Video-based Point Cloud Compression)에는 점유 맵(Occupancy Map) 손실/무손실 압축 기술이 포함되어 있다. V-PCC는 기존에 보급되어 있는 2차원 비디오 코덱(H.264/AVC, HEVC, AV1 등)을 그대로 활용할 수 있는 장점이 있는데, 대부분의 소비자 영상 기기에 포함되어 있는 2차원 비디오 복호화기 HW는 무손실을 지원하지 않는다. 따라서 V-PCC 복호화기의 폭넓은 상용화를 위해서는 부호화기에서 점유 맵의 손실 압축이 필수적이다. 본 논문은 V-PCC 부호화기의 점유 맵을 최소한의 압축 효율 저하로 손실 압축하기 위해 다양한 파라미터 실험을 통한 최적의 파라미터 값을 제시한다.