The Effect of Elevated Guideway Construction Tolerances on Vehicle Ride Quality

1975 ◽  
Vol 97 (4) ◽  
pp. 408-416 ◽  
Author(s):  
J. K. Hedrick ◽  
R. J. Ravera ◽  
J. R. Anderes
Keyword(s):  
Cross Section ◽  
Quality Criteria ◽  
Design Parameters ◽  
Ride Quality ◽  
Live Load ◽  
General Technique ◽  
Trade Off ◽  
Frequency Decomposition ◽  
Space Boundary

In this paper the ride quality of a vehicle traversing an elevated guideway is related directly to guideway construction tolerances and design parameters. Moreover, the construction tolerances are modeled in terms familiar to a guideway contractor. The tolerances modeled for an elevated, two-span semicontinuous, concrete guideway are: surface finish, camber deviations, pier survey errors, and pier settlement. The major design parameters relating to live-load deflection, stiffness (material and cross-section), and pier spacing are included. A general technique is presented for relating these tolerances to vehicle ride quality by means of a digital computer simulation. Various ride quality criteria are considered, including rms acceleration, acceleration spectral density, acceleration frequency decomposition, and a deterministic state space boundary. Numerical results are presented for a particular vehicle-guideway configuration and as such are valid only for the system considered. It is shown that for this system, equivalent ride quality can be maintained while adjusting the various construction tolerances. This trade-off capability allows the contractor to choose the least costly combination of tolerance parameters.

scholarly journals Justification of the Gravitational Seed Cleaning System Parameters

2020 ◽  
Vol 14 (4) ◽  
pp. 26-32
Author(s):  
V. G. Khamuev
Keyword(s):  
Cross Section ◽  
Complete Separation ◽  
Basic Material ◽  
Design Parameters ◽  
High Productivity ◽  
Cleaning System ◽  
Effi Ciency ◽  
Material Separation ◽  
Gravitational Method

The author researched the gravitational method of separating a grain heap, in which cleaning from large and small impurities was carried out without energy consumption, with the gravity material fl ow in vertical cleaning columns along fi xed zigzag separating combs.(Research purpose) To study the gravity column operation for cleaning selection seeds and substantiate its design parameters.(Materials and methods) A prototype gravity column was developed. The author experimentally determined: the combs teeth diameter; column throughput; the possibility of a more complete separation of the seed fraction from the basic material; completeness of large impurities separation. He compared the work of the gravity column and the fl at rocking sieve. He assessed the combs jamming by the cleaned culture seeds.(Results and discussion) The author noted that on wheat cleaning at a productivity of 45.6 kilogram per hour, the yield of the "waste" fraction was 0.5 percent, a loss of 0.07 percent, and at a productivity of 227.8 kilogram per hour – 0.98 and 0.35 percent, which corresponded to the initial requirements for the main technological operations for post-harvest processing of selection seeds.(Conclusions) It was found that a gravity column for separating selection wheat seeds small impurities separated particles with high effi ciency if they diff ered from each other in thickness of at least 0.3 millimeter with a gap between the comb bars of 2.0 millimeter and a bar cross-section diameter of 0.9 millimeter. It was determined that high productivity – up to 150 kilogram per hour – was possible with a column cross-section with sides of 60 and 70 millimeter. The author revealed practically the same quality of material separation when separating small impurities using both a sieve and a gravity column.

Computerized Tomography and C-Scan for Measuring Drilling-Induced Delamination in Composite Material Using Twist Drill and Core Drill

2007 ◽  
Vol 339 ◽  
pp. 16-20 ◽  
Author(s):  
H. Hocheng ◽  
Chung Chen Tsao
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Computerized Tomography ◽  
Cross Section ◽  
Thrust Force ◽  
Design Parameters ◽  
Tool Geometry ◽  
Ultrasonic Technique ◽  
Twist Drill

Delamination is one of the most concern defects in drilling of composite material. Delamination depends on the factors such as feed rate, tool geometry and wear. The mechanics of drilling composite materials has been examined along with the quality of the hole and the effect of tool design parameters. The capacity of computerized tomography (CT) showing sample cross-section in a nondestructive way made it successful in measuring the drilling-induced delamination. In the experiment, the correlation between thrust force and the measured delamination extent in use of twist drill and core drill is illustrated and compared with the known ultrasonic C-scan. It is compared with the ultrasonic technique and is demonstrated a feasible and an effective tool for the evaluation of drilling-induced delamination.

An experience of performing spirometry by trained general practitioners

2020 ◽  
pp. 34-36
Author(s):  
M. A. Pokhaznikova ◽  
E. A. Andreeva ◽  
O. Yu. Kuznetsova
Keyword(s):  
General Practitioners ◽  
Quality Criteria ◽  
Poor Quality ◽  
Male Gender ◽  
Study Research ◽  
The Poor ◽  
Quality Of Research ◽  
Forced Expiratory Maneuver ◽  
Maximal Effort

The article discusses the experience of teaching and conducting spirometry of general practitioners as part of the RESPECT study (RESearch on the PrEvalence and the diagnosis of COPD and its Tobacco-related aetiology). A total of 33 trained in spirometry general practitioners performed a study of 3119 patients. Quality criteria met 84.1% of spirometric studies. The analysis of the most common mistakes made by doctors during the forced expiratory maneuver is included. The most frequent errors were expiration exhalation of less than 6s (54%), non-maximal effort throughout the test and lack of reproducibility (11.3%). Independent predictors of poor spirogram quality were male gender, obstruction (FEV1 /FVC<0.7), and the center where the study was performed. The number of good-quality spirograms ranged from 96.1% (95% CI 83.2–110.4) to 59.8% (95% CI 49.6–71.4) depending on the center. Subsequently, an analysis of the reasons behind the poor quality of research in individual centers was conducted and the identified shortcomings were eliminated. The poor quality of the spirograms was associated either with the errors of the doctors who undertook the study or with the technical malfunctions of the spirometer.

Classification of methods for generating pseudo-CT from MRI images for MRI-alone RT

2017 ◽  
Vol 1 (3) ◽  
pp. 54
Author(s):  
BOUKELLOUZ Wafa ◽  
MOUSSAOUI Abdelouahab
Keyword(s):  
Performance Metrics ◽  
Radiation Treatment ◽  
Hybrid Methods ◽  
Dose Calculation ◽  
Absolute Error ◽  
Ct Images ◽  
General Technique ◽  
Therapy Field ◽  
The Brain

Background: Since the last decades, research have been oriented towards an MRI-alone radiation treatment planning (RTP), where MRI is used as the primary modality for imaging, delineation and dose calculation by assigning to it the needed electron density (ED) information. The idea is to create a computed tomography (CT) image or so-called pseudo-CT from MRI data. In this paper, we review and classify methods for creating pseudo-CT images from MRI data. Each class of methods is explained and a group of works in the literature is presented in detail with statistical performance. We discuss the advantages, drawbacks and limitations of each class of methods. Methods: We classified most recent works in deriving a pseudo-CT from MR images into four classes: segmentation-based, intensity-based, atlas-based and hybrid methods. We based the classification on the general technique applied in the approach. Results: Most of research focused on the brain and the pelvis regions. The mean absolute error (MAE) ranged from 80 HU to 137 HU and from 36.4 HU to 74 HU for the brain and pelvis, respectively. In addition, an interest in the Dixon MR sequence is increasing since it has the advantage of producing multiple contrast images with a single acquisition. Conclusion: Radiation therapy field is emerging towards the generalization of MRI-only RT thanks to the advances in techniques for generation of pseudo-CT images. However, a benchmark is needed to set in common performance metrics to assess the quality of the generated pseudo-CT and judge on the efficiency of a certain method.

THE QUALITY OF PUBLIC HOSPITALS IN CAN THO CITY, 2016

2018 ◽  
Vol 8 (6) ◽  
pp. 76-81
Author(s):  
Chu Cao Minh ◽  
Thang Vo Van ◽  
Dat Nguyen Tan ◽  
Hung Vo Thanh
Keyword(s):  
Hospital Medicine ◽  
Secondary Data ◽  
Quality Criterion ◽  
Quality Criteria ◽  
Public Hospitals ◽  
Ministry Of Health ◽  
Cross Sectional ◽  
Significant Difference ◽  
Can Tho City

Background: The criteria set of assessing hospital quality in Vietnam in 2016 was revied from the criteria set in 2013 by the Ministry of Health in order to help hospitals to self-assess towards improvinge quality of hospitals in the international integration context. The study aimed to assess the quality of public hospitals in Can Tho City according to the revised criteria set of the Ministry of Health in 2016 and compare the quality among three hospital ranks (including grade I, grade II, and grade III) via to 5 groups of quality criteria. Methods: A cross-sectional study, using secondary data analysis was applied to assess the service quality of 7 general public hospitals in Can Tho City. Results: The average total score of 7 hospitals is 245 and the average for the criteria of 7 hospitals is 2.99, which is just satisfactory. In the criterion of quality, criterion D and E had the lowest scores compared to the other three groups. There was no statistically significant difference (p = 0.076) among the mean scores for the three hospital categories. Conclusion: The quality of public hospitals in Can Tho city in 2016 only reached moderately good level (2.99). Interventions should be developed to improve the quality of hospitals, with particular emphasis on improving the quality of criteria groups D and E. Key words: Quality, hospital, medicine, health, public, Can Tho

DIAGNOSING QUALITY OF FRICTION SYSTEMS OF MECHANISMS OF DEVICES

2019 ◽  
Vol 1 (7) ◽  
pp. 10-13
Author(s):  
D. Yu. Ershov ◽  
I. N. Lukyanenko ◽  
E. E. Aman
Keyword(s):  
Surface Defects ◽  
Diagnostic Methods ◽  
Design Parameters ◽  
Diagnostic Model ◽  
Mechanical Assemblies ◽  
Local Defects ◽  
Relationship Of ◽  
The Relationship ◽  
Production And Operation

The article shows the need to develop diagnostic methods for monitoring the quality of lubrication systems, which makes it possible to study the dynamic processes of contacting elements of the friction systems of instrument mechanisms, taking into account roughness parameters, the presence of local surface defects of elements and the bearing capacity of a lubricant. In the present article, a modern diagnostic model has been developed to control the quality of the processes of production and operation of friction systems of instrument assemblies. With the help of the developed model, it becomes possible to establish the relationship of diagnostic and design parameters of the mechanical system, as well as the appearance of possible local defects and lubricant state, which characterize the quality of friction systems used in many mechanical assemblies of the mechanisms of devices. The research results are shown in the form of nomograms to assess the defects of the elements of friction mechanisms of the mechanisms of the devices.

Social Investment and Childcare Expansion

2017 ◽  
Author(s):  
Margarita León
Keyword(s):  
Early Childhood ◽  
Early Childhood Education ◽  
Perfect Match ◽  
Preschool Education ◽  
Conceptual Level ◽  
Social Investment ◽  
Trade Off ◽  
Childhood Education ◽  
Education And Care

The chapter first examines at a conceptual level the links between theories of social investment and childcare expansion. Although ‘the perfect match’ between the two is often taken for granted in the specialized literature as well as in policy papers, it is here argued that a more nuance approach that ‘unpacks’ this relationship is needed. The chapter will then look for elements of variation in early childhood education and care (ECEC) expansion. Despite an increase in spending over the last two decades in many European and Organisation for Economic Co-operation and Development (OECD) countries, wide variation still exists in the way in which ECEC develops. A trade-off is often observed between coverage and quality of provision. A crucial dividing line that determines, to a large extent, the quality of provision in ECEC is the increasing differentiation between preschool education for children aged 3 and above and childcare for younger children.

scholarly journals The use of mathematical modelling to analyse the process of mixing waters from different sources in water supply system

2018 ◽  
Vol 59 ◽  
pp. 00025
Author(s):  
Agnieszka Szuster – Janiaczyk ◽  
Rafał Brodziak ◽  
Jędrzej Bylka
Keyword(s):  
Mathematical Modeling ◽  
Water Quality ◽  
Quality Criteria ◽  
Supply System ◽  
Network Control ◽  
Quality Of Water ◽  
Water Mains ◽  
Different Sources ◽  
Mixing Water

One of the processes that significantly determines the quality of water to consumers is the process of mixing water from different sources in the water mains. Put to the network two or more chemically and biologically stable waters may result in the formation of water that will be deprived of these features. This article presents the german guidelines for analysing water quality for mixing waters from different sources, in various proportions. Then performed an analysis of utility the mathematical models,including quality criteria, for use in network control. An IT tool has been developed to manage selected water quality processes using mathematical modeling. The basis for implementing the tool was a network model created in Epanet integrated with the Matlab.

UBAR

2021 ◽  
Vol 20 (3) ◽  
pp. 1-25
Author(s):  
Elham Shamsa ◽  
Alma Pröbstl ◽  
Nima TaheriNejad ◽  
Anil Kanduri ◽  
Samarjit Chakraborty ◽  
...  
Keyword(s):  
Resource Management ◽  
Quality Of Experience ◽  
State Of The Art ◽  
State Of Charge ◽  
User Preference ◽  
Management Approach ◽  
High Quality ◽  
Trade Off ◽  
Run Time

Smartphone users require high Battery Cycle Life (BCL) and high Quality of Experience (QoE) during their usage. These two objectives can be conflicting based on the user preference at run-time. Finding the best trade-off between QoE and BCL requires an intelligent resource management approach that considers and learns user preference at run-time. Current approaches focus on one of these two objectives and neglect the other, limiting their efficiency in meeting users’ needs. In this article, we present UBAR, User- and Battery-aware Resource management, which considers dynamic workload, user preference, and user plug-in/out pattern at run-time to provide a suitable trade-off between BCL and QoE. UBAR personalizes this trade-off by learning the user’s habits and using that to satisfy QoE, while considering battery temperature and State of Charge (SOC) pattern to maximize BCL. The evaluation results show that UBAR achieves 10% to 40% improvement compared to the existing state-of-the-art approaches.

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