• Science of Emotion and Sensibility
• /
• v.21 no.2
• /
• pp.73-88
• /
• 2018

The present study examined how processing features of visual information near the hand would affect task switching. Recent studies reported enhanced cognitive control of visual information presented the near hands. To investigate the enhancement of cognitive control based on the relationship between hand proximity and attention, we implemented 2 experiments. In the task switching performance experiment, the hand proximity effect depended on modality of cue and target. The first experiment showed that stimuli near the hand received greater cognitive control than stimuli far from the hand, resulting in smaller switch cost. The result could rule out the feature-binding problem, which identifies reduced switch cost as the cause instead of hand proximity. Our results show that hand proximity actually reduced switch cost. In the second experiment, we examined the effects of hand nearness, modality, and their interaction on switch cost. In task switching, the target was always visual, and the cue was presented either visually or auditorily. In addition, we manipulated the cue-target interval to observe the preparation effect of cue. The results showed that a visual cue near the hand reduced switch cost by shortening task preparation time. Also, modality switching between an auditory cue and visual target was remarkable in a hand-near condition. The results for the visual cue could be interpreted as a benefit of rapid visual attention orienting. On the other hand, the results for the auditory cue could be interpreted as the cost of interference of modality switching by slower attentional disengagement of stimuli near the hands. Finally, modulation of switch cost by attention induced by hand nearness was discussed.

• The Korean Journal of Applied Statistics
• /
• v.32 no.3
• /
• pp.451-462
• /
• 2019

Document-term frequency matrix is a type of data used in text mining. This matrix is often based on various documents provided by the objects to be analyzed. When analyzing objects using this matrix, researchers generally select only terms that are common in documents belonging to one object as keywords. Keywords are used to analyze the object. However, this method misses the unique information of the individual document as well as causes a problem of removing potential keywords that occur frequently in a specific document. In this study, we define data that can overcome this problem as proximity data. We introduce twelve methods that generate proximity data and cluster the objects through two clustering methods of multidimensional scaling and k-means cluster analysis. Finally, we choose the best method to be optimized for clustering the object.

• International conference on construction engineering and project management
• /
• 2022.06a
• /
• pp.328-335
• /
• 2022

With the advance of robot capabilities and functionalities, construction robots assisting construction workers have been increasingly deployed on construction sites to improve safety, efficiency and productivity. For close-proximity human-robot collaboration in construction sites, robots need to be aware of the context, especially construction worker's behavior, in real-time to avoid collision with workers. To recognize human behavior, most previous studies obtained 3D human poses using a single camera or an RGB-depth (RGB-D) camera. However, single-camera detection has limitations such as occlusions, detection failure, and sensor malfunction, and an RGB-D camera may suffer from interference from lighting conditions and surface material. To address these issues, this study proposes a novel method of 3D human pose estimation by extracting 2D location of each joint from multiple images captured at the same time from different viewpoints, fusing each joint's 2D locations, and estimating the 3D joint location. For higher accuracy, the probabilistic representation is used to extract the 2D location of the joints, considering each joint location extracted from images as a noisy partial observation. Then, this study estimates the 3D human pose by fusing the probabilistic 2D joint locations to maximize the likelihood. The proposed method was evaluated in both simulation and laboratory settings, and the results demonstrated the accuracy of estimation and the feasibility in practice. This study contributes to ensuring human safety in close-proximity human-robot collaboration by providing a novel method of 3D human pose estimation.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.7 no.2
• /
• pp.71-78
• /
• 2012

Based on the Zigbee-based wireless sensor network, I suggest the way to reduce errors between the short distance, improving the accuracy of the presumed distance by revising the deviation of RSSI(Received Signal Strength Indication) values is to estimate the distance using only the RF signal power without the additional hardware. In general, the graph measured by RSSI values shows the proximity values which are ideally reduced in proportion to the distance under the free outdoor space in which LOS(Line-Of-Sight) is guaranteed. However, if the result of the received RSSI values are each substituted to the formula, it can produce a larger margin of error and less accurate measurement since it is based upon the premise that this free space is not affected by reflected waves or obstacles caused by the ground and electronic jamming engendered by the environment. Therefore, the purpose of this study is to reduce the margin of errors between the distances and to measure the proximity values with the ideal type of graph by suggesting the way to revise the received RSSI values in the light of these reflected waves or obstacles and the electronic jamming. In conclusion, this study proves that errors are reduced by comparing the proposed deviation correction method to the revised RSSI value.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2009.11a
• /
• pp.17-22
• /
• 2009

This research was conducted to investigate methods to strengthen the apartment community from the territoriality point of view. In order to achieve this goal, first of all the concept and the structure of territoriality are studied through articles and literature reviews to ensure a full understanding of the community strengthening-related plan elements suggested in the previous research. The study is then divided into the categories of semi-private territory and semi-public territory to pursue analysis based on the issues related to strengthening community such as possession, proximity, defense, boundary-regulation, and personalization in case by case studies. The results of case studies are as follows: in the case of possession with psychological concept of possession, the extension of private space and exclusive space are suggested. And for the concept of proximity, that is, the physical and psychological distance for sense of the same nature, increased opportunity of meeting the residents in the same building or same area are suggested And for the psychological proximity, familiar design and facilities for meeting and exchange-related methods are shown. For the case of indirect defense in defense concept, the methods related to monitoring and supervising facilities for protection are found. For the boundary-regulations, it is based on the concepts of physical and psychological borderlines; walls either vertical or horizontal, or such obstacle-related methods are suggested for the physical borderline, and space structure and symbols-related methods are found for psychological borderline. Finally, for the case of personalization which is related to the expression of identity, design-related methods are suggested.

• The KIPS Transactions:PartA
• /
• v.13A no.1 s.98
• /
• pp.11-18
• /
• 2006

In the Internet of various networks, it is difficult to reduce real routing time by just minimizing their hop count. We propose an adaptive proximity route selection method in DHT-based peer-to-peer systems, in which nodes select the nぉe with smallest lookup latency among their routing table entries as a next routing node. Using Q-Routing algorithm and exponential recency-weighted average, each node estimates the total latency and establishes a lookup table. Moreover, without additional overhead, nodes exchange their lookup tables to update their routing tables. Several simulations measuring the lookup latencies and hop-to-hop latency show that our method outperforms the original Chord method as well as CFS' server selection method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.10
• /
• pp.908-917
• /
• 2013

In this paper, we propose a discovery protocol for finding nearby mobile applications and services in a device-to-device communications system. The device-to-device communication technology enables proximity-based services such as mobile social networks and mobile marketing. For realizing these proximity-based services, it is essential to design a discovery protocol which pinpoints the devices with mobile applications of interest among hundreds and thousands of devices in proximity. In the infrastructure-less networks such as ad hoc networks, we can design the discovery protocol that periodically broadcasts a short discovery code containing the compressed information of the mobile applications. In this paper, we design the discovery protocol with the discovery code generated by using a hash function and a Bloom filter. We also mathematically analyze the performance of the proposed protocol.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
• /
• v.55 no.6
• /
• pp.604-613
• /
• 2018

In this study, we analyzed the variations in the received signal strength index (RSSI) measured from Bluetooth beacons based on the strength and propagation direction of Bluetooth low energy (BLE) signal. Using a smartphone, we performed field experiments to investigate RSSI variations in the BLE signal transmitted by non-directional and directional beacons in an amethyst mine. In case of non-directional beacons, as the distance between the Bluetooth beacon and smartphone decreased, the RSSI increases, whereas as the BLE signal strength increased, the RSSI average gradually increased. The mean value of RSSI measured from the directional beacons was changed without relation to the facing angle between the Bluetooth beacon and smartphone. The results of this study can be used as basic data for developing a Bluetooth beacon-based proximity warning system for underground mines.

• Fashion & Textile Research Journal
• /
• v.24 no.5
• /
• pp.647-654
• /
• 2022

Wearable devices come in a variety of shapes and sizes in numerous fields in numerous fields and are available in various forms. They can be integrated into clothing, gloves, hats, glasses, and bags and used in healthcare, the medical field, and machine interfaces. These devices keep track individuals' biological and behavioral data to help with health communication and are often used for injury prevention. Those with hearing loss or impaired vision find it more difficult to recognize an approaching person or object; these sensing devices are particularly useful for such individuals, as they assist them with injury prevention by alerting them to the presence of people or objects in their immediate vicinity. Despite these obvious preventive benefits to developing Internet of Things based devices for the disabled, the development of these devices has been sluggish thus far. In particular, when compared with people without disabilities, people with hearing impairment have a much higher probability of averting danger when they are able to notice it in advance. However, research and development remain severely underfunded. In this study, we incorporated a wearable detection system, which uses an infrared proximity sensor, into a backpack. This system helps its users recognize when someone is approaching from behind through visual and tactile notification, even if they have difficulty hearing or seeing the objects in their surroundings. Furthermore, this backpack could help prevent accidents for all users, particularly those with visual or hearing impairments.

• Electronics and Telecommunications Trends
• /
• v.28 no.2
• /
• pp.38-49
• /
• 2013

본고에서는 무선랜 기반 근접인식(proximity awareness) 모바일 서비스 제공에 필요한 관련 기술 동향 및 표준현황을 정리한다. 특히 수많은 기기들이 산재하는 모바일 D2D(Device to Device) 통신환경에서 인접 장치 및 서비스 발견 과정에 사용자 개입을 최소화할 수 있도록 접속 대상을 보고 선택하는 방식의 시선통신(look-and-link)과 네트워크 계층의 접속 이전에 주변 디바이스에서 제공되는 서비스를 미리 파악하거나 간단한 정보를 송수신할 수 있는 무결합 메시징(preassociation messaging) 연구동향을 소개한다. 이러한 기술은 셀룰러 중심의 기존 모바일 서비스들과 차별성을 가지며 무선랜 기술을 활용하는 D2D 환경에서 근접인식 모바일 서비스를 활성화할 수 있는 핵심 요소기술로 이용될 것이다.