• Title/Summary/Keyword: View Angle

Search Result 798, Processing Time 0.026 seconds

The effects of beam-column connections on behavior of buckling-restrained braced frames

  • Hadianfard, Mohammad Ali;Eskandari, Fateme;JavidSharifi, Behtash
    • Steel and Composite Structures
    • /
    • v.28 no.3
    • /
    • pp.309-318
    • /
    • 2018
  • Buckling Restrained Braced (BRB) frames have been widely used as an efficient seismic load resisting system in recent years mostly due to their symmetric and stable hysteretic behavior and significant energy dissipation capacity. In this study, to provide a better understanding of the behavior of BRB frames with various beam-column connections, a numerical study using non-linear finite element (FE) analysis is conducted. All models are implemented in the Abaqus software package following an explicit formulation. Initially, the results of the FE model are verified with experimental data. Then, diverse beam-column connections are modeled for the sake of comparison from the shear capacity, energy dissipation and frame hysteresis behavior points of view until appropriate performance is assessed. The considered connections are divided into three different categories: (1) simple beam-column connections including connection by web angle and connection by seat angle; (2) semi-rigid connection including connection by web and seat angles; and (3) rigid beam-column connections by upper-lower beam plates and beam connections with web and flange splices. Results of the non-linear FE analyses show that these types of beam-column connections have little effect on the maximum story drift and shear capacity of BRB frames. However, the connection type has a significant effect on the amount of energy dissipation and hysteresis behavior of BRB frames. Also, changes in length and thickness of the angles in simple and semi-rigid connections and changes in length and thickness of plates in rigid connections have slight effects (less than 4%) on the overall frame behavior.

A STUDY OF THE TEMPOROMANDIBULAR JOINT IN MALOCCLUSION USING TMJ TOMOGRAM AND CEPHALOGRAM (단층 및 두부 방사선 계측사진을 이용한 부정 교합자의 악관절에 관한 연구)

  • Hong, Soon Chang;Ryu, Young Kyu
    • The korean journal of orthodontics
    • /
    • v.22 no.1
    • /
    • pp.89-107
    • /
    • 1992
  • The purpose of this study was to investigate the difference between normal and malocclusion subjects in Temporomandibular joint. This study was based on the 44 subjects with normal occlusion, 30 subjects with Class II malocclusion, 30 subjects with Class III malocclusion before treatment. After submental vertex view analysis, each subject was given the TMJ Tomogram in centric relation and centric occlusion and the Cephalogram was taken with Quint Sectograph. The TMJ spaces were measured and analyzed statistically. Following results were obtained. 1. When centric relation was compared to centric occlusion, The condyles were positioned more posteriorly and superiorly in centric relation position of the normal occlusion group and the class II malocclusion group. In the Class III malocclusion group. There was no significant difference in the condylar position between centric occlusion and centric relation. 2. The condyles of the Class III malocclusion group were positioned more superiorly than the normal occlusion group and the Class II malocclusion group. 3. In the correlation between articular eminence posterior slope angle and lingual slope angle of the upper anterior central incisor, there was significant correlation in the normal occlusion group. But no significant correlation was found in the malocclusion group. 4. The mean value of the horizontal angulation of condylar head to the transear rod axis plane was $20.32^{\circ}{\pm}8.12^{\circ}$ in the normal occlusion group, $25.08^{\circ}{\pm}4.83^{\circ}$ in the class II malocclusion group, $14.68^{\circ}{\pm}4.08^{\circ}$ in the class III malocclusion group.

  • PDF

Analysis on the Pattern of Dragging Anchor in Actual Ship (실선 계측에 의한 주묘패턴 분석에 관한 연구)

  • Jung, Chang-Hyun;Kong, Gil-Young;Bae, Byung-Deug;Lee, Yun-Sok
    • Journal of Navigation and Port Research
    • /
    • v.33 no.8
    • /
    • pp.505-511
    • /
    • 2009
  • Vessels on anchoring are frequently dragged due to the increased area of wind pressure by enlargement of ship's size and sudden gust of winds in recent years. In the view point of the ship's navigators, the proper measurements corresponding to the dragging of anchor should be taken into account concerned about the time for the occurring of dragging by the external forces such as wind and wave, the pattern and speed of dragging and the possibility of collisions with any other vessels or obstacles. In this paper, it was examined the actual dragging anchor in T.S. HANBADA due to the wind and waves. From this case, it was found the critical external forces by which she was begun to dragged comparing the force by the wind, frictional resistance, drifting force and ship motion moment with the holding power. Also, through the analysis of the dragging pattern, it was known the alteration range of heading angle, swinging width and dragging speed etc.

The Usefulness of Arthroscopy in the Operative Treatment of Intra-Articular Calcaneal Fracture (관절 내 종골 골절의 수술적 치료에 있어 관절 내시경 사용의 유용성)

  • Chung, Kyung-Chil;Gwak, Heui-Chul;Kim, Chang-Wan;Kim, Jung-Han;Park, Dae-Hyun
    • Journal of Korean Foot and Ankle Society
    • /
    • v.13 no.1
    • /
    • pp.55-59
    • /
    • 2009
  • Purpose: We tried to evaluate the usefulness of the arthroscopy in the operative treatment of intra-articular calcaneal fracture. Materials and Methods: Between March 2005 and May 2008, 9 patients with intra-articular calcaneal fractures(Tongue type or Sanders type IIC) were treated with arthroscopically assisted percutaneous reduction and screw fixation. American orthopedic foot and ankle society (AOFAS) ankle-hindfoot score, visual analogue scale (VAS), preoperative and postoperative Bohler's angle and the rate of complication were evaluated. Results: AOFAS score at postoperative 1 year was 88.2 (range, 71-92), and mean VAS score was 2.8 (range, 1-4). Bohler angle was improved from preoperative mean $16.2^{\circ}$ to postoperative mean $29.7^{\circ}$. There were no complications such as wound problem, infection or nerve injury. Conclusion: Subtalar arthroscopy provides precise view of posterior facet during the operation. Therefore, it can be a useful tool in treating intra-articular calcaneus fractures, especially tongue type and Sanders type IIC fractures.

  • PDF

Hardware Configuration and Paradox Measurement for the Determination of Arrow Trajectory (화살의 이동궤적을 위한 하드웨어 구성 및 패러독스 측정)

  • Jeong, Yeong-Sang;Yu, Jung-Won;Lee, Han-Soo;Kim, Sung-Shin
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.21 no.3
    • /
    • pp.459-464
    • /
    • 2012
  • The point of impact, the shot group, and the flight traces depend on the combination of unique features which decide moving traces of the arrow (paradox of the archer, length of the arrow shaft, weight, angle of the feather, and spline of the arrow shaft). The more dense the impact points in the shot group and the earlier elimination of paradox of the archer, the higher assessment is given for the product. However, there is no way to objectively assess the efficiency and quality of the arrow, and there is no numeric data to be used as the basis for comparison with other products. Although capturing the images of flying arrow using a high-speed motion picture camera is possible, we are limited to observation from specific view angle only. Hence, the criteria for efficiency and quality assessment are mostly based on subjective opinions of experts or hunters, or review on consumers' remarks. In this paper, we propose a hardware composition that are based on three detection frames consisting of line lasers and photo diode arrays without the high-speed motion picture camera. Predicated on measured coordinates data, a nobel method for the archer's paradox measurement, a key parameter that determine the arrow's trajectory, and corresponding numerical analysis model is proposed.

GPS Satellite Repeat Time Determination and Orbit Prediction Based on Ultra-rapid Orbits (초신속궤도력 기반 GPS 위성 repeat time 산출 및 궤도 예측)

  • Lee, Chang-Moon;Park, Kwan-Dong;Kim, Hye-In;Park, Jae-Min
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.27 no.4
    • /
    • pp.411-420
    • /
    • 2009
  • To plan a GPS survey, they have to decide if a survey can be conducted at a specific point and time based on the predicted GPS ephemeris. In this study, to predict ephemeris, we used the repeat time of a GPS satellite. The GPS satellite repeat time was determined by analysing correlation among three-dimensional satellite coordinates provided by the 48-hour GPS ephemeris in the ultra-rapid orbits. By using the calculated repeat time and Lagrange interpolation polynomials, we predicted GPS orbits f3r seven days. As a result, the RMS of the maximum errors in the X, Y, and Z coordinates were 39.8 km 39.7 km and 19.6 km, respectively. And the maximum and average three-dimensional positional errors were 119.5 km and 48.9 km, respectively. When the maximum 3-D positioning error of 119.5 km was translated into the view angle error, the azimuth and elevation angle errors were 9.7'and 14.9', respectively.

Nostril Base Augmentation Effect of Alveolar Bone Graft

  • Lee, Woojin;Park, Hyung Joon;Choi, Hyun Gon;Shin, Dong Hyeok;Uhm, Ki Il
    • Archives of Plastic Surgery
    • /
    • v.40 no.5
    • /
    • pp.542-545
    • /
    • 2013
  • Background The aims of alveolar bone grafting are closure of the fistula, stabilization of the maxillary arch, support for the roots of the teeth adjacent to the cleft on each side. We observed nostril base augmentation in patients with alveolar clefts after alveolar bone grafting. The purpose of this study was to evaluate the nostril base augmentation effect of secondary alveolar bone grafting in patients with unilateral alveolar cleft. Methods Records of 15 children with alveolar clefts who underwent secondary alveolar bone grafting with autogenous iliac cancellous bone between March of 2011 and May of 2012 were reviewed. Preoperative and postoperative worm's-eye view photographs and reconstructed three-dimensional computed tomography (CT) scans were used for photogrammetry. The depression of the nostril base and thickness of the philtrum on the cleft side were measured in comparison to the normal side. The depression of the cleft side pyriform aperture was measured in comparison to the normal side on reconstructed three-dimensional CT. Results Significant changes were seen in the nostril base (P=0.005), the philtrum length (P=0.013), and the angle (P=0.006). The CT measurements showed significant changes in the pyriform aperture (P<0.001) and the angle (P<0.001). Conclusions An alveolar bone graft not only fills the gap in the alveolar process but also augments the nostril base after surgery. In this study, only an alveolar bone graft was performed to prevent bias from other procedures. Nostril base augmentation can be achieved by performing alveolar bone grafts in children, in whom invasive methods are not advised.

Fuel Economy Improvement Cruise Control Algorithm using Distance and Altitude Data of GPS in Expressway (고속도로에서 GPS 거리와 고도데이터를 이용한 연비 향상 정속 순항 제어 알고리즘)

  • Choi, Seong-Cheol;Lee, Jong-Hwa
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.19 no.6
    • /
    • pp.68-75
    • /
    • 2011
  • A vehicle fuel economy is very important issue in view of fuel cost and environmental regulation. It has been improved according to the performance improvement of the vehicle engine, power train and many components. It was evaluated at given mode (LA-4, FTP-75, etc) on an engine dynamometer or computer simulation program. In this paper, the fuel economy improvement cruise control algorithms as controling a vehicle velocity by road load calculated and predicted in a real expressway with gradient was studied. Firstly, the altitude and distance data which was measured with GPS sensor was already installed in the ECU of a vehicle. Then the vehicle equipped with GPS receiver is driven the same expressway. The ECU calculates the gradient angle and the in-/decreasing velocity using the gradient angle by comparing the current received distance and altitude data from GPS with the saved data ahead of the vehicle. Therefore the ECU can calculate and predict the vehicle velocity considering tolerance velocity of next position with running. Then the ECU controls the vehicle velocity to meet this predicted velocity in all section. Three cruise control algorithms with the different velocity profiles for the improvement of fuel economy are proposed and compared with the computer simulation results that the vehicle runs on Youngdong expressway. The proposed CVELCONT2 and CVELCONT3 algorithms were improved 3.7% and 4.8% of fuel economy compared with CONSTVEL which is steady cruising algorithm. These two algorithms are recommended as the Eco-cruise drive methodologies in this paper.

Fuel Economy improvement Method and Performance Evaluation Using Altitude Data (고도 데이터를 이용한 연비 향상 방안과 성능 평가)

  • Choi, Seong-Cheol;Kwon, Mann-Jun;Lee, Sang-Jun;Kim, Young-Il;Oh, Tae-Il;Ko, Kwang-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.13 no.5
    • /
    • pp.1947-1953
    • /
    • 2012
  • The vehicle fuel economy is very important issue in the view of global warming. This paper proposes the three fuel economy improvement algorithms which predict the velocity using altitude data of the positions in front of vehicle and estimates their performances. The proposed 3 algorithms are WMGA(Weighted Mean Gradient Angle), RAADE I, II(Reacceleration After Deacceleration I, II). This research extracts the distance and altitude data from received GPS data and calculates gradient angle and road load for each section. The velocity profile according to proposed algorithms is made for Youngdong highway of 213km. And the test vehicle runs along this highway and fuel economy is measured. RAADE II of proposed algorithms showed better performance by 3.571% in comparison to the conventional CVELCONT3.

The Landslide Probability Analysis using Logistic Regression Analysis and Artificial Neural Network Methods in Jeju (로지스틱회귀분석기법과 인공신경망기법을 이용한 제주지역 산사태가능성분석)

  • Quan, He Chun;Lee, Byung-Gul;Lee, Chang-Sun;Ko, Jung-Woo
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.19 no.3
    • /
    • pp.33-40
    • /
    • 2011
  • This paper presents the prediction and evaluation of landslide using LRA(logistic regression analysis) and ANN (Artificial Neural Network) methods. In order to assess the landslide, we selected Sarabong, Byeoldobong area and Mt. Song-ak in Jeju Island. Five factors which affect the landslide were selected as: slope angle, elevation, porosity, dry density, permeability. So as to predict and evaluate the landslide, firstly the weight value of each factor was analyzed by LRA(logistic regression analysis) and ANN(Artificial Neural Network) methods. Then we got two prediction maps using AcrView software through GIS(Geographic Information System) method. The comparative analysis reveals that the slope angle and porosity play important roles in landslide. Prediction map generated by LRA method is more accurate than ANN method in Jeju. From the prediction map, we found that the most dangerous area is distributed around the road and path.