• Title/Summary/Keyword: surrounding

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A study on the site analysis considering a fused relationship of the architectural site and surrounding context (건축대지와 주변 컨텍스트의 융합적인 연계성을 고려한 대지분석에 관한 연구)

  • Jun, In-Mok
    • Journal of the Korea Convergence Society
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    • v.8 no.5
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    • pp.275-285
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    • 2017
  • The architectural site exists in the context of the surrounding environment as the background of architectural design, and the architecture exists in the connection between the site and the surrounding environment therefore, the plan of the building starts from the analysis of the site, and its consequences too meaning can be found in the relation with the surrounding environment. Ironically, however, there are no direct papers describing site analysis with this meaning. Therefore, this paper categorizes the site analysis items around the four environments of Land, Water, Fire, and Wind that constitute the environment of the ecosystem, furthermore, in order to apply the result of the fusion information to the architectural design by synthesizing the organic correlation between the inside and the surrounding environment, i created the '9sectors system', which is a combination of 'horizontal 3 and vertical 3' to provide a more rational and efficient architectural plan. Through the progress of the project using this system, it is considered that it is a more applicable method of the site analysis data than the existing site analysis method.

Efficient Power Reduction Technique of LiDAR Sensor for Controlling Detection Accuracy Based on Vehicle Speed (차량 속도 기반 정확도 제어를 통한 차량용 LiDAR 센서의 효율적 전력 절감 기법)

  • Lee, Sanghoon;Lee, Dongkyu;Choi, Pyung;Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.15 no.5
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    • pp.215-225
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    • 2020
  • Light detection and ranging (LiDAR) sensors detect the distance of the surrounding environment and objects. Conventional LiDAR sensors require a certain amount of a power because they detect objects by transmitting lasers at a regular interval depending on a constant resolution. The constant power consumption from operating multiple LiDAR sensors is detrimental to autonomous and electric vehicles using battery power. In this paper, we propose two algorithms that improve the inefficient power consumption during the constant operation of LiDAR sensors. LiDAR sensors with algorithms efficiently reduce the power consumption in two ways: (a) controlling the resolution to vary the laser transmission period (TP) of a laser diode (LD) depending on the vehicle's speed and (b) reducing the static power consumption using a sleep mode depending on the surrounding environment. A proposed LiDAR sensor with a resolution control algorithm reduces the power consumption of the LD by 6.92% to 32.43% depending on the vehicle's speed, compared to the maximum number of laser transmissions (Nx·max). The sleep mode with a surrounding environment-sensing algorithm reduces the power consumption by 61.09%. The proposed LiDAR sensor has a risk factor for 4-cycles that does not detect objects in the sleep mode, but we consider it to be negligible because it immediately switches to an active mode when a change in surrounding conditions occurs. The proposed LiDAR sensor was tested on a commercial processor chip with the algorithm controlling the resolution according to the vehicle's speed and the surrounding environment.

MPC based Steering Control using a Probabilistic Prediction of Surrounding Vehicles for Automated Driving (전방향 주변 차량의 확률적 거동 예측을 이용한 모델 예측 제어 기법 기반 자율주행자동차 조향 제어)

  • Lee, Jun-Yung;Yi, Kyong-Su
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.3
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    • pp.199-209
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    • 2015
  • This paper presents a model predictive control (MPC) approach to control the steering angle in an autonomous vehicle. In designing a highly automated driving control algorithm, one of the research issues is to cope with probable risky situations for enhancement of safety. While human drivers maneuver the vehicle, they determine the appropriate steering angle and acceleration based on the predictable trajectories of surrounding vehicles. Likewise, it is required that the automated driving control algorithm should determine the desired steering angle and acceleration with the consideration of not only the current states of surrounding vehicles but also their predictable behaviors. Then, in order to guarantee safety to the possible change of traffic situation surrounding the subject vehicle during a finite time-horizon, we define a safe driving envelope with the consideration of probable risky behaviors among the predicted probable behaviors of surrounding vehicles over a finite prediction horizon. For the control of the vehicle while satisfying the safe driving envelope and system constraints over a finite prediction horizon, a MPC approach is used in this research. At each time step, MPC based controller computes the desired steering angle to keep the subject vehicle in the safe driving envelope over a finite prediction horizon. Simulation and experimental tests show the effectiveness of the proposed algorithm.

The Effect of Construction on Ambient PM-10 in the Surrounding Area - Focusing on the Field Case Research - (건설공사가 주변지역 대기 중의 PM-10에 미치는 영향 - 현장사례 연구를 중심으로 -)

  • Song, Hee-Bong;Kim, Eun-Kyung;Kwon, Jong-Dae;Park, Su-Kyoung;Yoon, Hyun-Suk;Ju, Myeong-Hui;Bae, Gi-Soo
    • Journal of Environmental Health Sciences
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    • v.41 no.3
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    • pp.163-170
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    • 2015
  • Objectives: This study evaluated the effect of construction on ambient PM-10 in the surrounding area. Methods: Four study sites were selected from total AAQMN 11 points in Daegu city. All the four study sites were located near under or completed construction. Mean monthly PM-10 in 2007 to 2013 were analyzed. Results: Impact of residential construction on PM-10 was more obvious than industrial area. PM-10 was positively associated with number of construction near the study site. When there were 2 or 3 construction sites, PM-10 level was higher. Wind direction and the surrounding terrain affected PM-10. Conclusions: Construction has a strong influence on PM-10 in the surrounding Area. Reduce PM-10 there is the need for special construction site management. Proper management is required to minimize fugitive dust in construction sites.

A Study on Growth Conditions of the Protected Trees in Gyeongju-si (경주시 보호수 생육실태 연구)

  • Heo Sang-Hyun;Ha Jae-Ho
    • Journal of Environmental Science International
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    • v.13 no.10
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    • pp.883-890
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    • 2004
  • The purpose of this study is to survey and analyze the growth, management and surrounding environment of the big and old trees in Kyoungju-si or the cultural assets alive in our history, and thereby, provide for some data useful to their reasonable protection and use of their surrounding areas. As a result of surveying the growth conditions of the big and old trees, it was found that the height of new grass was 10.5cm on average, the activity scale of the wood was 7.2k$\Omega$, the soil hardness was $16.7kg/cm^2$, the soil acidity was pH 4.8, and the soil moisture was $13.3\%$. Such findings suggest that the soil has been acidified by people's frequent passages, but that the other growth conditions are more or less normal. Hence, it is desirable to secure a sufficient space around the trees or reduce people's stamping pressure with some mechanisms. On the other hand, the visible conditions of the trees were found more or less normal, but many trees remained cut or barked (with some cavities), requiring an optimal treatment or measure. Lastly, as the population has decreased in the suburban traditional villages, the surrounding environment seems to be less vulnerable to people's frequent visits. Nevertheless, in consideration of the fact that there are only a few public space for the villagers, it is deemed necessary to rearrange or maintain some parts of the surrounding environment as public space for villagers or hikers.

Investigation of divergence tunnel excavation according to horizontal offsets between tunnels

  • Hong, Soon-Kyo;Oh, Dong-Wook;Kong, Suk-Min;Lee, Yong-Joo
    • Geomechanics and Engineering
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    • v.21 no.2
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    • pp.111-122
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    • 2020
  • In most cases in urban areas, construction of divergence tunnel should take into account proximity to existing tunnel in operation. This inevitably leads to deformation of adjacent structures and surrounding ground. Preceding researches mainly dealt with reinforcing of the diverging section for the stability including the pillar. This has limitations in investigating the interactive effects between existing structures and surrounding ground due to the excavation of the divergence tunnel. In this study, the complex interactive behavior of pile, the operating tunnel, and the surrounding ground according to horizontal offsets between the two adjacent tunnels was quantitatively analyzed based on conditions diverged from operating tunnel in urban areas. The effects on ground structures confirmed by analyzing the ground surface settlements, pile settlements, and the axial forces of the pile. The axial forces of lining in operating tunnel investigated to estimate their impact on existing tunnel. In addition, in order to identify the deformation of the surrounding ground, the close range photogrammetry applied to the laboratory model test for confirming the underground displacements. Two-dimensional finite element numerical analysis was also performed and compared with the results. It identified that the impact of excavating a divergence tunnel decreased as the horizontal offset increased. In particular, when the horizontal offset was larger than 1.0D (D is the diameter of operating tunnel), the impact on existing structures further reduced and the deformation of surrounding ground was concentrated at the top of the divergence tunnel.

A FINITE ELEMENT STRESS ANALYSIS OF THE STRESS DISTRIBUTION AND THE SHOCK ABSORPTION IN AN OSSEOINTEGRATED IMPLANT-NATURAL TOOTH SUPPORTED FIXED PARTIAL DENTURE (골유착성 임프란트와 자연치를 이용한 고정성 국소의치에서 응력분산 및 충격흡수에 관한 유한요소법적 응력분석)

  • Jeong Chang-Mo;Lee Ho-Yong
    • The Journal of Korean Academy of Prosthodontics
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    • v.30 no.4
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    • pp.582-610
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    • 1992
  • The long-term success of any dental implant is dependent upon the optimization of stresses which occur during oral function and parafunction. Especially, it has been suggested that there is an unique set of problems associated with joining an osseointegrated implant and a natural tooth with a fixed partial denture. For this particular case, although many literatures suggest different ways to avoid high stress concentrations on the bone surrounding the implant under static and dynamic loading conditions, but few studies on the biomechanical efficacy of each assertion have been reported. The purpose of this investigation was to evaluate the efficacies of clinically suggested methods on stress distribution under static load and shock absorption under dynamic load, using two dimensional finite element method. In FEM models of osseointegrated implant-natural tooth supported fixed partial dentures, calculations were made on the stresses in surrounding bone and on the deflections of abutments and superstructure, first, to compare the difference in stress distribution effects under static load by the flexure of fastening screw or prosthesis, or intramobile connector, and second, to compare the difference in the shock absorption effects under dynamic load by intramobile connector or occlusal veneering with composite resin. The results of this analysis suggest that : 1. Under static load condition, using an implant design with fastenign screw connecting implant abutment and prosthesis or increasing the flexibility of fastening screw, or increasing the flexibility of prosthesis led to the .increase in height of peak stresses in cortical bone surrounding the implant, and has little effect on stress change in bone around the natural tooth. 2. Under static load condition, intramobile connector caused the substantial decrease in stress concentration in cortical bone surrounding the implant and the slight increase in stress in bone around the natural tooth. 3. Under dynamic load condition, both intramobile connector and composite resin veneering showed shock absorption effect on bone surrounding the implant and composite resin veneering had a greater shock absorption effect than intramobile connector.

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A framework for modelling mechanical behavior of surrounding rocks of underground openings under seismic load

  • Zhang, Yuting;Ding, Xiuli;Huang, Shuling;Pei, Qitao;Wu, Yongjin
    • Earthquakes and Structures
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    • v.13 no.6
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    • pp.519-529
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    • 2017
  • The surrounding rocks of underground openings are natural materials and their mechanical behavior under seismic load is different from traditional man-made materials. This paper proposes a framework to comprehensively model the mechanical behavior of surrounding rocks. Firstly, the effects of seismic load on the surrounding rocks are summarized. Three mechanical effects and the mechanism, including the strengthening effect, the degradation effect, and the relaxation effect, are detailed, respectively. Then, the framework for modelling the mechanical behavior of surrounding rocks are outlined. The strain-dependent characteristics of rocks under seismic load is considered to model the strengthening effect. The damage concept under cyclic load is introduced to model the degradation effect. The quantitative relationship between the damage coefficient and the relaxation zone is established to model the relaxation effect. The major effects caused by seismic load, in this way, are all considered in the proposed framework. Afterwards, an independently developed 3D dynamic FEM analysis code is adopted to include the algorithms and models of the framework. Finally, the proposed framework is illustrated with its application to an underground opening subjected to earthquake impact. The calculation results and post-earthquake survey conclusions are seen to agree well, indicating the effectiveness of the proposed framework. Based on the numerical calculation results, post-earthquake reinforcement measures are suggested.

Investigation of Standard Error Range of Non-Contact Thermometer by Environment (외부 환경 변화에 의한 비 접촉 체온계의 오차 범위 측정)

  • Kim, Jeongeun;Park, Sangwoong;Choi, Heakyung
    • Journal of The Korean Society of Integrative Medicine
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    • v.8 no.4
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    • pp.307-321
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    • 2020
  • Purpose : A person infected by SARS-CoV2 may present various symptoms such as fever, pain in lower respiratory tract, and pneumonia. Measuring body temperature is a simple method to screen patients. However, changes in the surrounding environment may cause errors in infrared measurement. Hence, a non-contact thermometer controls this error by setting a correction value, but it is difficult to correct it for all environments. Therefore, we investigate device error values according to changes in the surrounding environment (temperature and humidity) and propose guidelines for reliable patient detection. Methods : For this study, the temperature was measured using three types of non-contact thermometers. For accurate temperature measurement, we used a water bath kept at a constant temperature. During temperature measurement, we ensured that the temperature and humidity were maintained using a thermo-hygrometer. The conditions of the surrounding environment were changed by an air conditioner, humidifier, warmer, and dehumidifier. Results : The temperature of the water bath was measured using a non-contact thermometer kept at various distances ranging from 3~10 cm. The value measured by the non-contact thermometer was then verified using a mercury thermometer, and the difference between the measured temperatures was compared. It was observed that at normal surrounding temperature (24 ℃), there was no difference between the values when the non-contact thermometer was kept at 3 cm. However, as the distance of the non-contact thermometer was increased from the water bath, the recorded temperature was significantly different compared with that of mercury thermometer. Moreover, temperature measurements were conducted at different surrounding temperatures and the results obtained significantly varied from when the thermometer was kept at 3 cm. Additionally, it was observed that the effect on temperature decreases with an increase in humidity Conclusion : In conclusion, non-contact thermometers are lower in lower temperature and dry weather in winter.

Deformation characteristics of surrounding rock in the intersection area between main tunnel and construction adit of the Xianglushan tunnel

  • Yunjuan Chen;Mengyue Liu;Fuqiang Yin;Lewen Zhang;Jing Wu;Jinrui Li
    • Geomechanics and Engineering
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    • v.38 no.1
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    • pp.1-13
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    • 2024
  • The construction adit plays a pivotal role in enhancing the working face during the excavation of long-distance and deep hydraulic tunnels. However, the intersection zone between the main tunnel and the construction adit exhibits more intricate deformation patterns in surrounding rock, posing a significant threat to stability during excavation. Taking the Xianglushan tunnel in Yunnan Province, China, as a case study, the FLAC3D software is employed to simulate the excavation process at the intersection. The simulation results are verified combined with the field deformation monitoring results, and the spatial distribution of tunnel rock deformation in the intersection area are analyzed. Five excavation conditions with different intersection angles are simulated, and the surrounding rock deformation of the tunnel intersection area with different intersection angles is analyzed, and its influence range is discussed. The results show that: (1) The surrounding rock deformation in the intersection area increases rapidly during the tunnel excavation. With the increase of construction distance, the deformation of intersection area is gradually stable. (2) The deformation distribution of the tunnel rock is uneven, and the deformation of main tunnel near the intersection area is larger than that far away from the intersection area. (3) With the increase of the intersection angle, the surrounding rock deformation of the tunnel intersection and its influence range decreases gradually. The research results have certain guiding significance for the construction safety of the tunnel intersection area.