• Title/Summary/Keyword: 이동 거리

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From Librarians' Perspectives on Physical Accessibility of Public Libraries (사서의 시각으로 본 공공도서관의 접근성)

  • Park, Sung-Jae
    • Journal of the Korean Society for information Management
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    • v.29 no.1
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    • pp.135-156
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    • 2012
  • The purpose of this study is to ascertain librarian's perceptions on their users' library access and its patterns. Interviews with seven library staff reveal physical accessibility issues including spatial relationships between libraries and other facilities such as shopping malls and schools, travel distance, transportation mode, and temporal perspectives of library access. The results from the interviews corroborate the findings from secondary analysis using household travel data. However, interviewees do not have a clear picture of how much their users travel and spend to access their libraries. This is true, even though these factors are critical to analyze physical accessibility. Based on the findings, this study makes recommendations to improve the accessibility of public libraries. Suggestions include the concept of sponsorships with other facilities, the placing of material drop-boxes on the main route, and providing library programs during lunch time.

Design and Estimation of Cordless Transmitter & Receiver for Measurement of Crane Moving Range (크레인의 이동거리 측정을 위한 무선 송수신기 설계 및 평가)

  • Kim, Tae-Soo;Oh, Inn-Yeal;Chun, Joong-Chang
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.4
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    • pp.808-814
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    • 2007
  • In this paper, the measurement system of crane moving range is concerned with range recognition technology using phase and magnitude of radio wave. By the proposed technology, we design the radio transmitter and receiver and realize the measurement system, and save the data in disk that is earned from 900Mhz RF signal, middle frequency 450khz of analog signal. As a result of RF measurement, we got 9.3 dBm of RF output and 96 dBc@10khz of phase noise. Range information is earned the data through digital signal processing of IF signal. For the estimation of range measured, we analyze the difference between real range and measurement range, and also suggest the method to remove the measurement error using average processing and amplitude properties. A result is 0.12 and 0.00422 deviation in l0mn-30m and within 5m respectively, and then 2.4E-04 deviation in 4m by using compensation of level characteristics lately.

Performace Analysis on Nodes' Moving distances in Mobile Sensor Field (이동 센서 환경에서 노드 이동 거리에 따른 성능 변화 연구)

  • Park, Se-Young;Yun, Dai Yeol
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • pp.505-507
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    • 2021
  • In a Wireless Sensor Network (WSN), the wireless data transmission environment plays an important role in system performance. In the proposed mobility model moving distance of sensor nodes has a great influences on communication performance. Transmission/receiving distance (d), path loss (L), sensitivity, Bit Error Rate (BER), Signal-to-Noise Ratio (SNR) are considerations when designing a wireless communication system. MANET is a form of network in which only wireless terminals communicate with each other independently and move without any assistance of an existing infrastructure network. This paper is research on the optimized power usage method which is study on the effect of the moving distance of mobile nodes on the overall energy efficiency of the system in WSN. The purpose of this study is to extend the life of the entire network by proposing the mobile distance of sensor nodes within the communication available range.

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Hunminjungum Keypad (훈민정음 글자판)

  • Kim, Sungwook
    • Journal of Internet Computing and Services
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    • v.22 no.4
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    • pp.29-49
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    • 2021
  • This paper proposes the Hunminjungum Keypad that applied the creation principle of Hunminjungum to the design of keypad. The proposed keypad arranged 28 letters of Hunminjungum to have correlations with each other between consonants, between vowels, and between consonants and vowels. That is, Consonant buttons are arranged by grouping letters of the same sound by sounds of five voices. And the vowel buttons are arranged at the bottom and the right side of the consonant area according to the position where a vowel is attached to the consonant. In the meantime, Hangul keypads have mainly used 12 button keypads in 4 lines and 3 columns. These keypads have structurally disadvantageous in the touch count and moving distance. Recently, keypads with many letter buttons such as QWERTY and single-vowel are also used a lot. If the number of letter buttons provided in the keypad increases, touch count decreases. And If the letter buttons are arranged to have a correlation with each other, the moving distance becomes smaller. The experimental results show that the proposed keypad has high efficiency in all evaluation factors such as touch count, moving distance and input time.

A Study on Distance Estimation in Virtual Space According to Change of Resolution of Static and Dynamic Image (가상현실공간에서 정적 및 동적 이미지의 해상도 변화에 따른 거리추정에 관한 연구)

  • Ryu, Jae-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.109-119
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    • 2011
  • The virtual reality (VR) technology has been used as the application of architectural presentation or simulation tool in the field of industry. The high immersion and intuitive visual information are the great merits of design evaluation or environmental simulation when we are using the virtual environments. But the distortion of distance perception in VR is still a big problem when the accuracy of distance presentation is strictly required. For example, distance estimation is especially important when the virtual environments are applied to the presentational tool for evaluation the space design or planning in the field of architecture. If there are some perception error between the built space in real and represented space in virtual, the accurate design evaluation or modification of design is hard to be carried out during the design development stage. In this paper, we have carried out some experiments about distance estimation in the immersive virtual environments to verify the factors and their influence. We made a hypothesis that the lack of the information for the user in VR causes the different distance estimation from the real world because users are usually comfortable with moving fast and long distance in VR environments compared with moving slow and short distance in real space. So, we carried out basic experiment to prove our hypothesis that the lack of information makes subjects estimate the distance of walking in VR shorter compared with the same distance in real. Also, among the factors that probably affect the distance estimation in VR, we have verified the influence of the image resolution. The influence of resolution degradation of image on the distance estimation was verified with the condition of static and dynamic images. The results showed that the resolution has deep relation with the distance estimation. For example, the subject underestimated the distance at the lower resolution condition. We also found the methods of the making the lower resolution image could affect on the visual perception of subjects.

Broadcasting and Caching Schemes for Location-dependent Queries in Urban Areas (도심환경에서 위치의존 질의를 위한 방송과 캐싱 기법)

  • Jung Il-dong;Yu Young-ho;Lee Jong-hwan;Kim Kyongsok
    • Journal of KIISE:Databases
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    • v.32 no.1
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    • pp.56-70
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    • 2005
  • The results of location-dependent queries(LDQ) generally depend on the current locations of query issuers. Many mechanisms, e.g. broadcast scheme, hoarding, or racking policy, have been developed to improve the system peformance and provide better services, which are specialized for LDQs. Considering geographical adjacency of data and characteristics oi target area, caching policy and broadcast scheme affect the overall performance in LDQ. For this reason, we propose both the caching policy and broadcast scheme, which these features are reflected in. Based on the adjacency of data in LDQ, our broadcast scheme use Hilbert curve to cluster data. Moreover, in order to develop the caching policy suitable for LDQ on urban area, we apply the moving distance of a MH(Mobile Host) to our caching policy We evaluate the performance of the caching policy measuring the workload of MHs and the correctness of LDQ results and the performance of the broadcast scheme measuring the average setup-time of MHs in our experiments. Finally, we expect that our caching policy Provides more correct answers when executing LDQ in focal cache and leads significant improvement of the performance of MHs. It also seems quite probable that our broadcast scheme leads improvement of battery life of the MH.

Assessment of Runout Distance of Debris using the Artificial Neural Network (인공신경망을 이용한 사태물질 이동거리 산정)

  • Seo Yong-Seok;Chae Byung-Gon;Kim Won-Young;Song Young-Suk
    • The Journal of Engineering Geology
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    • v.15 no.2
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    • pp.145-154
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    • 2005
  • This study conducted to develop an assessment method of runout distance of debris flow that is a major type of landslides in Korea. In order to accomplish the objectives, this study performed detailed field survey of runout distance and laboratory soil tests using 24 landslides over three pilot sites. Based on the data of the field survey and the laboratory tests, an assessment method of runout distance was suggested using the artificial neural network. The input data for the analysis of artificial neural network are change rate of slope angle, Permeability coefficient of in-situ soil, dry density, void ratio, volume of debris and the measured runout distance. The analyzed results using the artificial neural network show low error rate of inference distributing lower than $10\%$. Some cases have $5\%$ and $2\%$ of error rates of inferences. The results can be thought as excellent teaming rates. However, it is difficult to be accepted as excellent results if it is considered with the results derived using only 24 landslide data. Therefore, more landslide data should be surveyed and analyzed to increase the confidence in the assessment results.

A Study on Transportation Characteristics of Debris dependent on Geologic Conditions (지질조건에 따른 사태물질 이동특성 고찰)

  • Chae Byung-Gon;Kim Won-Young;Lee Choon-Oh;Kim Kyeong-Su;Cho Yong-Chan;Song Young-Suk
    • The Journal of Engineering Geology
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    • v.15 no.2
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    • pp.185-199
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    • 2005
  • Properties of sliding materials are dependent on the lithology because debris is the product of rock weathering processes. In order to characterize transportation behavior of debris dependent of debris types, this study selected 26 debris flows over three areas composed with different rock weathering types and topographic conditions. Analyses of lithology, weathering, and topographic characteristics were performed by detailed field survey. Based on the field survey data, transportation behavior of debris was studied at the aspect of the relationship of grain size and volume of debris as well as topographic conditions. According to the study results, change of slope angle is very influential factor on runout distance of debris among the topographic factors. Because the sliding velocity and the energy of debris are frequently changed and more irregular on an undulating slope, the unout distance of debris is larger than that of an uniformly dipping slope. Runout distance of debris is also influenced by volume and grain size of debris. Volume of debris in the gabbro is four or five times larger than that of the granite area because it is controlled by the lithology. Considered with grain size distribution, runout distance of debris is longer in the gabbro area which is composed with irregular grain size bearing large corestones than that in the medium grained granite area.

Estimation of Displacements and Velocities of Objects from Soccer Image Sequences (축구 영상 시퀀스로부터 물체 이동거리와 속도 측정)

  • Nam, Si-Wook;Yi, Jong-Hyon;Lee, Jae-Cheol;Park, Yeung-Gyu;Kim, Jai-Hie
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.2
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    • pp.1-8
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    • 2001
  • In this paper, we propose an algorithm which estimates the displacements and velocities of objects in the soccer field from the soccer image sequences. Assuming the time interval of an object movement is given, we transform the object positions into those in the soccer field model and compute the distance and the velocity. When four corresponding pairs of the feature points, such as the crossing points of the lines in the soccer field, exist and three of them are not on a line, we transform the object positions in the soccer image into those in the soccer field by using the perspective displacement field model. In addition, when the soccer image has less than four feature points, we first transform the object positions into those in the image which has more than four feature points, and then transform the positions into those in the soccer field again. To find the coordinate transformation between two images, we estimate the panning and zooming for consecutive images in the sequence. In the experimental results, we quantitatively evaluated the estimation accuracy by applying our algorithm to the synthetic. soccer image sequences generated by graphic tools, and applied it to the real soccer image sequences for broadcasting to show its usefulness.

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A Study on Shoulder Joint Motions in the Caudal Gliding of Kaltenborn-Evjenth Concept (칼텐본-에비엔즈컨셉의 어깨관절 아래쪽미끄러뜨림 적용시 관절의 이동성 연구)

  • Choi, Wan-Suk;Park, Ju-Hyun;Jung, Bong-Jae;Moon, Ok-Kon;Min, Kyung-Ok;An, Ho-Jung
    • Journal of the Korean Society of Radiology
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    • v.6 no.5
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    • pp.427-433
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    • 2012
  • This study aimed at identifying changes in the acromiohumeral distance (AHD) and arm when the caudal gliding gradeII and III of Kaltenborn-Evjenth Concept$^{(R)}$ are applied to the right glenohumeral joint. The humeral head moved down about 5mm from the initial position when the gliding gradeII was applied, and about 8mm from the initial position when the gliding gradeIII was applied. Although men showed a higher acromiohumeral distance per grade than women in comparisons by gender for the acromiohumeral distance, there was no significant difference in statistics. The Abduction angle improved about $10^{\circ}$ from the initial angle when the gliding gradeII was applied, and about $12^{\circ}$ from the initial angle when the gliding gradeIII was applied. Although women showed the abduction angle greater than men for every grade in comparisons by gender for the abduction angle, there was no significant difference in statistics. Based on the aforesaid findings, the extent of kinematic changes in the humeral head could be identified when the gliding grades were applied. Accordingly, it is considered that more scientific evidence based treatments could be expected if influences on the surrounding structures by these changes could be learned through more studies in the future.