Experiment for bed erosion focusing on combination of horizontal distance and overlapping height between main and counter Sabo dam

2016 ◽  
pp. 471-477
Author(s):  
H. Watabe ◽  
K. Kaitsuka ◽  
M. Sugiyama ◽  
T. Itoh ◽  
H. Muramatsu ◽  
...  
Keyword(s):  
Horizontal Distance ◽  
Bed Erosion

Napfmarathon versus Stadtmarathon: Eine Annäherung an das Konzept des Leistungskilometers

2015 ◽  
Vol 63 (1) ◽  
Keyword(s):  
Accurate Estimation ◽  
Horizontal Distance ◽  
First Approximation ◽  
The City

The aim of this study was to investigate differences in course times of a mountainmarathon (Napfmarathon) versus a city Marathon. Therefore all participants of Napfmarathon were screened concerning a double participation on a city marathon (Zürich, Winterthur, Lausanne, Luzern) and the course time were compared. Of key interest was the influence of ascents and descents which were quantified according to ­guidelines of Youth & Sport (Jugend + Sport / Jeunesse et Sport), whereby in first approximation 100 meter of ascent, 150 meter of descent (more than 20%) and 1 km of horizontal distance were taken as a simallar performance correlat. For the identified double starter different average times per km resulted. For the city marathon with an average time of 4 min 52 sec and for the Napfmarathon with 4 min 28 sec. If speed per km was calculated only with ascent and horizontal distances having performance relevance an average time of 4 min 56 sec per km was identified. This effect seems to be independet from distance absolved, resulting for Halbmarathon on an average time of distance of 4 min 13 sec, for Napfmarathon of 4 min 4 sec and for the performance concept only with ascent an average time per km of 4 min 16 sec. These analysis reveal, that if only ascent is taxed average course times differ less than 5 sec for both distances. For these particular reasons we recommend for running events to calculate only based on ascent and horizontal distances making necessary adjustments based on length of course, steepness of ascent and descent, character of terain (middle-country, pre-alps, alpes) for accurate estimation of course times.

QUALITATIVE CHANGES IN RHYTHMIC GYMNASTICS HOOP THROWS FROM THE PERSPECTIVE OF BIOMECHANICAL ANALYSIS

2020 ◽  
pp. 1-8
Author(s):  
Raluca Tanasa
Keyword(s):  
Correlation Coefficient ◽  
Video Recording ◽  
Biomechanical Analysis ◽  
Fundamental Groups ◽  
Horizontal Distance ◽  
Video Recordings ◽  
Rhythmic Gymnastics ◽  
Female Gymnasts ◽  
Execution Technique ◽  
Qualitative Changes

Throws and catches in rhythmic gymnastics represent one of the fundamental groups of apparatus actuation. They represent for the hoop actions of great showmanship, but also elements of risk. The purpose of this paper is to improve the throw execution technique through biomechanical analysis in order to increase the performance of female gymnasts in competitions. The subjects of this study were 8 gymnasts aged 9-10 years old, practiced performance Rhythmic Gymnastics. The experiment consisted in video recording and the biomechanical analysis of the element “Hoop throw, step jump and catch”. After processing the video recordings using the Simi Motion software, we have calculated and obtained values concerning: launch height, horizontal distance and throwing angle between the arm and the horizontal. Pursuant to the data obtained, we have designed a series of means to improve the execution technique for the elements comprised within the research and we have implemented them in the training process. Regarding the interpretation of the results, it may be highlighted as follows: height and horizontal distance in this element have values of the correlation coefficient of 0.438 and 0.323, thus a mean significance of 0.005. The values of the arm/horizontal angle have improved for all the gymnasts, the correlation coefficient being 0.931, with a significance of 0.01. As a general conclusion, after the results obtained, it may be stated that the means introduced in the experiment have proven their efficacy, which has led to the optimisation of the execution technique, thus confirming the research hypothesis.

Effect of Cutting Roots Vertically at a Place with Different Horizontal Distance from Plant on Yield and Grain Storage Capacity of Summer Maize

2016 ◽  
Vol 42 (12) ◽  
pp. 1805 ◽  
Author(s):  
Zhen-He XU ◽  
Ming-Lei LIANG ◽  
Du-Xu LU ◽  
Mei LIU ◽  
Peng LIU ◽  
...  
Keyword(s):  
Storage Capacity ◽  
Grain Storage ◽  
Horizontal Distance ◽  
Summer Maize

Field Observation and Simulation of Sediment Resuspension in a Shallow Lake

1988 ◽  
Vol 20 (6-7) ◽  
pp. 263-270 ◽  
Author(s):  
K. Otsubo ◽  
K. Muraoka
Keyword(s):  
Numerical Simulation ◽  
Shallow Lake ◽  
Water Wave ◽  
Field Data ◽  
Sediment Resuspension ◽  
Field Research ◽  
Lake Kasumigaura ◽  
Bed Erosion ◽  
Current Water ◽  
Good Agreement

The dispersion and resuspension of sediments in Takahamairi Bay basin of Lake Kasumigaura were studied by means of field research and numerical simulation. The field data on wind direction and velocity, lake current, water wave, and turbidity were shown. Based on these results, we discuss how precipitated sediments were resuspended in this shallow lake. To predict the turbidity and the depth of bed erosion, a simulation model was established for this lake. The calculated turbidity showed good agreement with the field data. According to the simulated results, the turbidity reaches 200 ppm, and the bed is eroded several millimeters deep when the wind velocity exceeds 12 m/s in the lake.

scholarly journals Assessment of the Retromolar Canal in Taiwan Subpopulation: A Cross-Sectional Cone-Beam Computed Tomography Study in a Medical Center

Tomography ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 219-227
Author(s):  
Yen-Wen Shen ◽  
Wan-Chun Chang ◽  
Heng-Li Huang ◽  
Ming-Tzu Tsai ◽  
Lih-Jyh Fuh ◽  
...  
Keyword(s):  
Medical Center ◽  
Third Molar ◽  
Mandibular Canal ◽  
Cone Beam ◽  
Horizontal Distance ◽  
Taiwanese Population ◽  
Mandibular Bone ◽  
Second Molar ◽  
The Third ◽  
Retromolar Canal

The retromolar canal is an anatomical variation that occurs in the mandibular bone. The retromolar canal typically originates in the mandibular canal on the distal side of the third molar and extends forward and upward to the retromolar foramen (RMF), which contains the neurovascular bundle. Accidentally damaging the neurovascular bundle in the retromolar canal during the extraction of the third molar, dental implant surgery, or maxillofacial orthognathic surgery may lead to subsequent complications such as incomplete local anesthesia, paresthesia, and bleeding during operation. The objective of this study was to investigate the prevalence of the RMF in the Taiwanese population in a medical center by using dental cone-beam computed tomography (CBCT) and to identify the position of the RMF in the mandibular bone. The dental CBCT images for the mandibular bone of 68 hemi-mandible were uploaded to the medical imaging software Mimics 15.1 to determine the prevalence of the RMF in the Taiwanese population and the three positional parameters of the RMF in the mandibular bone: (1) The diameter of the RMF, (2) the horizontal distance from the midpoint of the RMF to the distal cementoenamel junction of the second molar, and (3) the vertical distance from the midpoint of the RMF to the upper border of the mandibular canal. Seven RMFs were observed in the 68 hemi-mandibles. Thus, the RMF prevalence was 10.3%. In addition, the diameter of the RMF was 1.41 ± 0.30 mm (mean ± standard deviation), the horizontal distance from the midpoint of the RMF to the distal cementoenamel junction of the the second molar was 12.93 ± 2.87 mm, and the vertical distance from the midpoint of the RMF to the upper border of the mandibular canal below second molar was 13.62 ± 1.3487 mm. This study determined the prevalence of the RMF in the Taiwanese population in a medical center and its relative position in the mandibular bone. This information can provide clinicians with a reference for posterior mandible anesthesia and surgery to ensure medical safety.

Threshold velocity of non-Newtonian fluids to initiate solids bed erosion in horizontal conduits

2021 ◽  
pp. 108256
Author(s):  
Tran A. Tong ◽  
Yaxin Liu ◽  
Evren Ozbayoglu ◽  
Mengjiao Yu ◽  
Reza Ettehadi ◽  
...  
Keyword(s):  
Newtonian Fluids ◽  
Threshold Velocity ◽  
Bed Erosion

scholarly journals A Systematic Approach to Predict the Behavior of Cough Droplets Using Feedforward Neural Networks Method

Fluids ◽  
2021 ◽  
Vol 6 (2) ◽  
pp. 76
Author(s):  
Irfan Bahiuddin ◽  
Setyawan Bekti Wibowo ◽  
M. Syairaji ◽  
Jimmy Trio Putra ◽  
Cahyo Adi Pandito ◽  
...  
Keyword(s):  
Machine Learning ◽  
Disease Transmission ◽  
Systematic Approach ◽  
Feedforward Neural Networks ◽  
Feedforward Neural Network ◽  
Horizontal Distance ◽  
Droplet Generator ◽  
Droplet Model ◽  
Droplet Behavior ◽  
Diameter Reduction

Coronavirus disease 2019 (Covid-19) has been identified as being transmitted among humans with droplets from breath, cough, and sneezes. Understanding the droplets’ behavior can be critical information to avoid disease transmission, especially while designing a device deals with human air respiratory. Although various studies have provided enormous computational fluid simulations, most cases are too specific and quite challenging to combine with other similar studies directly. Therefore, this paper proposes a systematic approach to predict the droplet behavior for coughing cases using machine learning. The approach consists of three models, which are droplet generator, mask model, and free droplet model modeled using feedforward neural network (FFNN). The evaluation has shown that the three FFNNs models’ accuracies are relatively high, with R-values of more than 0.990. The model has successfully predicted the evaporation effect on the diameter reduction and the completely evaporated state, which can be considered unlearned cases for machine learning models. The predicted horizontal distance pattern also agrees with the data in the literature. In summary, the proposed approach has demonstrated the capability to predict the diameter pattern according to the experimental or previous work data at various mask face types.

scholarly journals Acute Effects of Handheld Loading on Standing Broad Jump in Youth Athletes

2021 ◽  
Vol 18 (9) ◽  
pp. 5046
Author(s):  
Wei-Hsun Tai ◽  
Ray-Hsien Tang ◽  
Chen-Fu Huang ◽  
Shin-Liang Lo ◽  
Yu-Chi Sung ◽  
...  
Keyword(s):  
High Speed ◽  
Center Of Mass ◽  
Reaction Force ◽  
Sampling Rate ◽  
Random Order ◽  
Horizontal Distance ◽  
Acute Effects ◽  
Vertical Ground Reaction Force ◽  
Strength And Conditioning ◽  
Peak Knee

The study aimed to investigate the acute effects of handheld loading on standing broad jump (SBJ) performance and biomechanics. Fifteen youth male athletes (mean age: 14.7 ± 0.9 years; body mass: 59.3 ± 8.0 kg; height: 1.73 ± 0.07 m) volunteered to participate in the study. Participants were assigned to perform SBJ with and without 4 kg dumbbells in a random order. Kinematic and kinetic data were collected using 10 infrared high-speed motion-capture cameras at a 250 Hz sampling rate and two force platforms at a 1000 Hz sampling rate. A paired t-test was applied to all variables to determine the significance between loading and unloading SBJs. Horizontal distance (p < 0.001), take-off distance (p = 0.001), landing distance (p < 0.001), horizontal velocity of center of mass (CoM; p < 0.001), push time (p < 0.001), vertical impulse (p = 0.003), and peak horizontal and vertical ground reaction force (GRF; p < 0.001, p = 0.017) were significantly greater in loading SBJ than in unloading SBJ. The take-off vertical velocity of CoM (p = 0.001), take-off angle (p < 0.001), peak knee and hip velocity (p < 0.001, p = 0.007), peak ankle and hip moment (p = 0.006, p = 0.011), and peak hip power (p = 0.014) were significantly greater in unloading SBJ than in loading SBJ. Conclusions: Acute enhancement in SBJ performance was observed with handheld loading. The present findings contribute to the understanding of biomechanical differences in SBJ performance with handheld loading and are highly applicable to strength and conditioning training for athletes.

scholarly journals Fluctuation of magnitude of wave loads for a long array of bottom-mounted cylinders

2019 ◽  
Vol 868 ◽  
pp. 244-285 ◽  
Author(s):  
Xiaohui Zeng ◽  
Fajun Yu ◽  
Min Shi ◽  
Qi Wang
Keyword(s):  
Incidence Angle ◽  
Local Maximum ◽  
Destructive Interference ◽  
Horizontal Distance ◽  
Wave Loads ◽  
Wave Load ◽  
Intrinsic Mechanism ◽  
Fluctuation Phenomenon ◽  
Analytical Formulae ◽  
Incident Waves

For wave loads on cylinders constituting a long but finite array in the presence of incident waves, variations in the magnitude of the load with the non-dimensional wavenumber exhibit interesting features. Towering spikes and nearby secondary peaks (troughs) associated with trapped modes have been studied extensively. Larger non-trapped regions other than these two are termed Region III in this study. Studies of Region III are rare. We find that fluctuations in Region III are regular; the horizontal distance between two adjacent local maximum/minimum points, termed fluctuation spacing, is constant and does not change with non-dimensional wavenumbers. Fluctuation spacing is related only to the total number of cylinders in the array, identification serial number of the cylinder concerned and wave incidence angle. Based on the interaction theory and constructive/destructive interference, we demonstrate that the fluctuation characteristics can be predicted using simple analytical formulae. The formulae for predicting fluctuation spacing and the abscissae of every peak and trough in Region III are proposed. We reveal the intrinsic mechanism of the fluctuation phenomenon. When the diffraction waves emitted from the cylinders at the ends of the array and the cylinder concerned interfere constructively/destructively, peaks/troughs are formed. The fluctuation phenomenon in Region III is related to solutions of inhomogeneous equations. By contrast, spikes and secondary peaks are associated with solutions of the eigenvalue problem. This study of Region III complements existing understanding of the characteristics of the magnitude of wave load. The engineering significances of the results are discussed as well.

scholarly journals Difficulties and modifications in the use of available methods for hydraulic conductivity measurements in highly clogged horizontal subsurface flow constructed wetlands

2017 ◽  
Vol 76 (7) ◽  
pp. 1666-1675 ◽  
Author(s):  
Mateus Pimentel Matos ◽  
André Baxter Barreto ◽  
Gabriel Rodrigues Vasconcellos ◽  
Antonio Teixeira Matos ◽  
Gustavo Ferreira Simões ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Constructed Wetlands ◽  
Subsurface Flow ◽  
The Other ◽  
Good Representation ◽  
Horizontal Distance ◽  
Conductivity Measurements ◽  
Construction Time ◽  
Horizontal Subsurface Flow ◽  
Subsurface Flow Constructed Wetlands

Despite the fact that several authors consider the available measurement methods of hydraulic conductivity (ks) suitable for a good representation of the bed condition and clogging potential in horizontal subsurface flow constructed wetlands, others have questioned their adequacy. In this work, hydraulic conductivity measurements with conventional and modified methods were undertaken in two small full-scale units, one planted with cattail (Typha latifolia) and the other unplanted. Both units had already been operating for seven years and showed a high degree of clogging. It was observed that the use of the falling head method, with the introduction of the tubes during the test, provided results without a clear spatial trend. On the other hand, tests done on monitoring wells inserted during construction time showed, as expected, ks increasing with the horizontal distance from the inlet, but without reflecting actual field conditions. It was observed that, as the bed became more clogged, the use of the reported methods became more complex, suggesting the need of other methodologies. The use of planted fixed reactors (removable baskets installed in the bed) with evaluation of ks at constant head in the laboratory showed potential for the characterization of the hydrodynamic properties of the porous medium.

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