• Title/Summary/Keyword: Trails

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The Fuzzy Steering Control Using a Slope Direction Estimation Method for Small Unmanned Ground Vehicle (경사방향 추정 기법을 이용한 소형로봇의 퍼지 조향 제어)

  • Lee, Sang Hoon;Huh, Jin Wook;Kang, Sincheon;Lee, Myung Chun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.6
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    • pp.721-728
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    • 2012
  • The tracked SUGVs(Small Unmanned Ground Vehicles) are frequently operated in the narrow slope such as stairs and trails. But due to the nature of the tracked vehicle which is steered using friction between the track and the ground and the limited field of view of driving cameras mounted on the lower position, it is not easy for SUGVs to trace narrow slopes. To properly trace inclined narrows, it is very important for SUGVs to keep it's heading direction to the slope. As a matter of factor, no roll value control of a SUGV can makes it's heading being located in the direction of the slope in general terrains. But, the problem is that we cannot directly control roll motion for SUGV. Instead we can control yaw motion. In this paper, a new slope driving method that enables the vehicle trace the narrow slopes with IMU sensor usually mounted in the SUGV is suggested which including an estimation technique of the desired yaw angle corresponding to zero roll angle. In addition, a fuzzy steering controller robust to changes in driving speed and the stair geometry is designed to simulate narrow slope driving with the suggested method. It is shown that the suggested method is quite effective through the simulation.

A study on Secure Payment Method & Security Technology of Electronic Commerce (전자상거래의 보안기술과 지불방법에 관한 연구)

  • 조원길
    • The Journal of Information Technology
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    • v.2 no.1
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    • pp.35-52
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    • 1999
  • This study introduced the new technologies that are expanding the realm of electronic commerce to the Internet and small business. Each of the key components of electronic commerce(contracts, signatures, notaries, payment systems and adult trails)are supported in the new electronic commerce. Electronic commerce is more than just handling purchase transactions and funds transfers over the internet. Despite Electronic commerce's past roots in transactions between large corporations, banks, and other financial institutions, the use of the internet as a way to bring Electronic commerce to the individual consumer has led to shift in viewpoint. Over the past few years, both the press and the business community have increased their focus on Electronic commerce involving the consumer Effective payment system should be established for the internet commerce. In this study, we examined the current development and application of Electronic payment system. Two different payment systems are used and under application. One is IC-card type of payment system which has gained popularity in England, Hong-Kong, and many other countries as a substitution of cash. The other type of payment system is e-cash, which is used more conveniently for the payment through internet. The question of which method is better fitted for the internet commerce should be evaluated in the view of cost and benefit since the associated technology is still under evolution. This study conducted a study on Secure Payment Method & Security Technology of Electronic Commerce

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Effect Verification of Wearable Assisting Wear for Increasing Golf Carry Distance (골프 비거리 증가를 위한 기능성 보조 웨어의 효과 검증)

  • Park, Yang-Sun;Woo, Byung-Hoon;Lim, Young-Tae
    • Korean Journal of Applied Biomechanics
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    • v.22 no.4
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    • pp.421-428
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    • 2012
  • The purpose of this study was to verify the effects of developed assisting wear which maximize trunk(back) muscle's stretch-shortening effect during backswing and downswing for increasing golf ball carrying distance. Design and fabrication of assistive wear were performed based on the results of analyzed data of trunk EMG activity from the golf drive swings of elite professional male golfers during back swing and downswing phases. After the prototype of wear was produced, surface EMG and Flight scope tests were conducted to verify the effectiveness of the wear for increasing distance to the professional golfers. Results indicated that wearing trial showed significant longer carry distance than the non-wearing trial(p<.001). The carry distance of wearing trial showed an average 229 m compared to the non-wearing trial, the average 225 m. The swing with wearing also produced significantly faster ball speed than the trial without wearing(p<.05). Average 245 Km/h and 244 Km/h were produced for the swing with and without wearing trails, respectively. EMG results also indicated that the muscle activity of left psoas was significantly increased for wearing trial during downswing and near the impact. Thus, this may affect positively to increase club head speed. The activity of the left latissimus dorsi was dramatically increased during the final stage of swing. This generates elongation effect for longer follow-through and increased impulse between club and ball so eventually valid assistance to increase carry distance. Therefore, the developed assisting wear was proved to be effective tool for increasing golf ball carry distance with maximizing trunk(back) muscle's stretch-shortening effect during backswing and downswing.

Public Art Work for Creating Hangang Artpark - Focus on A Project 'Thinking of Each Other' -

  • Maeng, Wookjae
    • Journal of recreation and landscape
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    • v.12 no.4
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    • pp.67-78
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    • 2018
  • Hangang Artpark construction is an enterprise founded in 2018 that involved installing public artworks created by 37 different people (teams) in Hangang Park located in Yeouido and Ichon Park. An iconic public space in Seoul, Hangang Park is turning into an even better public space due to the efforts to change the park into an eco-friendly, cultural-artistic space in tandem with the change in times. The objective of the Hangang Artpark construction business is to augment the environmental and scenic value of Hangang not only to provide a space for leisurely activities but also to revive it as a cultural-artistic area. This is a study of the concept and the design and installation processes of "Thinking of each other", a project by the Hangang Artpark construction business. This art piece has been installed in the wetlands and it trails along Ichon Hangang Park, which was created during the environmental recovery project. The piece consists of sculptures molded into animal shapes that are unique to the location and ecology of the area, displayed in harmony with the park's street furniture. By showing the coexistence of animals that existed in Hangang in the past along with the current inhabitants and the natural enemies of these inhabitants, the piece displays an ecofriendly scene. Moreover, by incorporating this piece into the street facilities of the park, such as gazebos, streetlights, surveillance cameras, and perches, the piece exhibits a different kind of street view compared to the installation style of other conventional environmental artworks. The various sculptures are installed along with the street facilities throughout the trail, rather than in a specific location intended for artworks, thereby achieving harmony with the park scene. In so doing, the piece elicits in the beholder an environment-friendly way of thinking, and at the same time, gives them a sense of calm and pleasure. Further, the paper researches the methods of safely installing art pieces in public spaces and of maintaining these installations.

Evaluation of Slope Stability of Taebaeksan National Park using Detailed Soil Map (정밀토양도를 이용한 태백산국립공원의 사면안정성 평가)

  • Kim, Young-Hwan;Jun, Byong-Hee;Jun, Kye-Won
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.2
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    • pp.65-72
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    • 2019
  • More than 64% of Korea's land is occupied by mountain regions, which have terrain characteristics that make it vulnerable to mountain disasters. The trails of Taebaeksan Mountain National Park-the region considered in this study-are located in the vicinity of steep slopes, and therefore, the region is vulnerable to landslides and debris flow during heavy storms. In this study, a slope stability model, which is a deterministic analysis method, was used to examine the potential occurrence of landslides. According to the soil classification of the detailed soil map, the specific weight of soil, effective cohesion, internal friction angle of soil, effective soil depth, and ground slope were used as the parameters of the model, and slope stability was evaluated based on the DEM of a 1 m grid. The results of the slope stability analysis showed that the more hazardous the area was, the closer the ratio of groundwater/effective soil depth is to 1.0. Further, many of the private houses and commercial facilities in the lower part of the national park were shown to be exposed to danger.

Rockfall Behavior with Catchment Area Condition (포집공간 조건에 따른 낙석의 거동)

  • Lee, Jundae;Kwon, Youngcheul;Bae, Wooseok
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.1
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    • pp.35-42
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    • 2019
  • Various development works inevitably increase cutting slopes due to land use, and many of trails managed by different authorities are being deteriorated by long-term weathering. Collapse of slopes causes unavoidable damage of property and loss of lives because of its uncertainty and difficulty in predicting its occurrence. In order to overcome the unavoidability, America, Japan, and several European nations analyze the kinetic energy and moving distance when rocks of upper slope move along the inclined plane, via field tests and computerized interpretation of the test results. Also, they are making efforts to develop measures with which the kinetic energy of the rocks moving along the slope is absorbed and fails to reach to specific structures. However, domestic researches just focus on fragmentary prediction of rockfall using existing programs, and there have been few approaches to identify interpretation methods appropriate for domestic cases or determination of parameters. In this context, we in this study defined rockfall types and affecting factors and analyzed effects of parameters using a general-purpose rockfall simulation program to understand principles of rockfall and to estimate effects of various parameters.

Determinants of Users' Satisfaction and Behavioral Intention in Jirisan Trail of Korea (지리산숲길 이용객의 만족도와 행동의도 영향 요인 연구)

  • Lee, Hye Rin;Kim, Jae Jun;Cho, Eun Kyung;Kang, Min Ji;Han, Sang Yeol
    • Journal of Korean Society of Forest Science
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    • v.100 no.2
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    • pp.273-282
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    • 2011
  • This study was aimed to identify determinants of users' satisfaction and behavioral intention in Jirisan trail of Korea and provide effective trail building and management strategy. The result of survey by 645 trail users showed that four dimensions were derived from 14 satisfaction items, which were experiential resources, cost resources, information, amenities. Of these dimensions, experiential resources along trails including natural environment, the level of trail development, trail condition, cultural & tourist resources, kindness of residents had the greatest effect on overall satisfaction and behavioral intention, which included revisit intention, recommendation intention and continuance intention. According to analysis by detailed variables, natural environment, road signs, kindness of residents and related information significantly affected overall satisfaction and behavioral intention.

Meta-analysis of the Effect of Proprioceptive Neuromuscular Facilitation Training on Gait Ability in Patients with Storke

  • Jeun, Young-Ju
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.8
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    • pp.165-172
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    • 2021
  • The purpose of this meta-analysis was to determine the efficacy of proprioceptive neuromuscular facilitation training on Gait. We included all randomized controlled trials assessing the efficacy of proprioceptive neuromuscular facilitation training on gait ability control in patients after stroke. This study was conducted according to the PRISMA guideline. CINAHL, PubMed and RISS were searched for studies published up to December 2020, and all randomized controlled trails assessing PNF intervention were included. This analysis included only randomized controlled trials. A total of 12 studies were selected from 1475 records obtained from the databases. The meta-analysis was performed using the R software. The overall intervention effect was moderate (standardized mean difference (SMD): 0.67, 95% confidence interval (CI): 0.50-0.84). Additionally, Gait rite (SMD: 0.69), 10m walking test (SMD: 0.59) had medium effect sizes. These findings indicate that PNF is an effective intervention for improving gait ability in patients stroke.

Analysis of Rockfall Behavior about Slope Ditch (비탈면 Ditch에 대한 낙석의 거동 해석)

  • Lee, Jundae;Bae, Wooseok
    • Journal of the Korean GEO-environmental Society
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    • v.23 no.2
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    • pp.37-47
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    • 2022
  • Recently, with the establishment of active stabilization measures, large-scale collapse of slopes is decreasing. However, the frequency of rockfalls due to the destabilization of floating stones or boulder within or above the slope has not been decreased significantly. As a measure for stabilizing rockfall and disaster prevention, protection methods such as rockfall barriers and rockfall protection nets are typically applied. However, the approach to catching the rockfall in a catchment area by reducing the energy of the rockfall and changing the rolling condition of the rockfall is relatively insignificant. Therefore, in this study, using a general-purpose rockfall simulation program, the change in the rolling characteristics of rockfall according to the specifications of the ditch installed under the slope was investigated. It is expected that the research results can be used as basic data to determine the specifications of the ditch that can be applied to general roads or trails.

GPU-based Parallel Ant Colony System for Traveling Salesman Problem

  • Rhee, Yunseok
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.2
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    • pp.1-8
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    • 2022
  • In this paper, we design and implement a GPU-based parallel algorithm to effectively solve the traveling salesman problem through an ant color system. The repetition process of generating hundreds or thousands of tours simultaneously in TSP utilizes GPU's task-level parallelism, and the update process of pheromone trails data actively exploits data parallelism by 32x32 thread blocks. In particular, through simultaneous memory access of multiple threads, the coalesced accesses on continuous memory addresses and concurrent accesses on shared memory are supported. This experiment used 127 to 1002 city data provided by TSPLIB, and compared the performance of sequential and parallel algorithms by using Intel Core i9-9900K CPU and Nvidia Titan RTX system. Performance improvement by GPU parallelization shows speedup of about 10.13 to 11.37 times.