Evaluation of weigh-in-motion in Manitoba

1999 ◽  
Vol 26 (5) ◽  
pp. 655-666 ◽  
Author(s):  
Xun Zhi ◽  
Ahmed Shalaby ◽  
Dan Middleton ◽  
Alan Clayton

The primary objective of a weigh-in-motion (WIM) system is to provide highway designers and agencies with information on the loads and traffic volumes using a particular highway, thereby facilitating improved pavement design, management, and weight enforcement. In this paper, the historic performance of WIM systems in Manitoba is evaluated. The results indicate that large numbers of unreasonable data are produced from the WIM systems, calibration procedures are not standardized, and there is drift in calibration. The performance of the Brokenhead WIM system was evaluated through a detailed survey conducted at the Brokenhead WIM site and the Westhawk Permanent Truck Weigh Station in August 1997. The Brokenhead site is on the Trans-Canada highway east of Winnipeg. It is the only WIM system in the country that measures truck characteristics and movements between eastern and western Canada. The survey produced a large database permitting the comparison of truck dimension measurements, truck weights, and vehicle classification between those produced by the WIM system and those observed manually. The results indicate that WIM axle-spacing data sets were outside the tolerance for 95% conformity specified by the American Society for Testing and Materials (ASTM). The system classified 5 to 9 axle combination trucks more accurately than some 2- and 3-axle vehicles. The WIM system underestimated about 90% of truck weights in the survey period. The degree of underestimation exceeded 50% of the corresponding static weights. This finding highlights the importance of quality control and corrections on WIM data prior to their use in research or engineering practice.Key words: weigh-in-motion, vehicle classification, calibration, axle spacing, axle load.

Author(s):  
Nikiforos Stamatiadis ◽  
David L. Allen

The increased use of equipment having automatic vehicle classification capabilities and weigh-in-motion devices produces a large amount of new data that can provide some insights into understanding traffic patterns more efficiently. These data can be used in determining seasonal adjustment factors for correcting traffic counts, in estimating truck traffic for highway cost allocation studies, and in predicting traffic volumes for roadways. However, due to practical limitations, it is not possible to obtain continuous data collection for all roads; thus, short-term counts are usually performed. Therefore, it is important to understand the relationship of the data obtained in a short-term period to those for the entire year. A study is currently under way that determines these relationships and develops seasonal adjustment factors for the state of Kentucky. The first step of the study was a survey of current uses of vehicle classification data and methods used for data collection throughout the United States. The results indicated that most states use no seasonal adjustment factors nor are they planning to develop any factors in the near future. At the same time, analysis of 2 years of vehicle classification data was used to develop seasonal and daily factors for Kentucky. Currently, the validation of these factors is under way. The preliminary analysis indicated that seasonal adjustment factors are essential in developing accurate estimates of traffic volumes for each vehicle type, and their use can improve the estimation of daily volumes.


1995 ◽  
Vol 5 (2) ◽  
pp. 249-263
Author(s):  
John F. Wilson

Over the last decade, a noteworthy number of published studies have, in one fashion or another, been defined with reference to religious denominations. This is an arresting fact, for, coincidentally, the status of religious denominations in the society has been called into question. Some formerly powerful bodies have lost membership (at least relatively speaking) and now experience reduced influence, while newer forms of religious organization(s)—e.g., parachurch groups and loosely structured movements—have flourished. The most compelling recent analysis of religion in modern American society gives relatively little attention to them. Why, then, have publications in large numbers appeared, in scale almost seeming to be correlated inversely to this trend?No single answer to this question is adequate. Surely one general factor is that historians often “work out of phase” with contemporary social change. If denominations have been displaced as a form of religious institution in society in the late twentieth century, then their prominence in earlier eras is all the more intriguing.


Geophysics ◽  
2002 ◽  
Vol 67 (4) ◽  
pp. 1028-1037 ◽  
Author(s):  
R. James Brown ◽  
Robert R. Stewart ◽  
Don C. Lawton

This paper proposes a multicomponent acquisition and preprocessing polarity standard that will apply generally to the three Cartesian geophone components and the hydrophone or microphone components of a 2‐D or 3‐D multicomponent survey on land, at the sea bottom, acquired as a vertical seismic profile, vertical‐cable, or marine streamer survey. We use a four‐component ocean‐bottom data set for purposes of illustration and example. A primary objective is a consistent system of polarity specifications to facilitate consistent horizon correlation among multicomponent data sets and enable determination of correct reflectivity polarity. The basis of this standard is the current SEG polarity standard, first enunciated as a field‐recording standard for vertical geophone data and hydrophone streamer data. It is founded on a right‐handed coordinate system: z positive downward; x positive in the forward line direction in a 2‐D survey, or a specified direction in a 3‐D survey, usually that of the receiver‐cable lines; and y positive in the direction 90° clockwise from x. The polarities of these axes determine the polarity of ground motion in any component direction (e.g., downward ground motion recording as positive values on the vertical‐geophone trace). According also to this SEG standard, a pressure decrease is to be recorded as positive output on the hydrophone trace. We also recommend a cyclic indexing convention, [W, X, Y, Z] or [0, 1, 2, 3], to denote hydrophone or microphone (pressure), inline (radial) geophone, crossline (transverse) geophone, and vertical geophone, respectively. We distinguish among three kinds of polarity standard: acquisition, preprocessing, and final‐display standards. The acquisition standard (summarized in the preceding paragraph) relates instrument output solely to sense of ground motion (geophones) and of pressure change (hydrophones). Polarity considerations beyond this [involving, e.g., source type, wave type (P or S), direction of arrival, anisotropy, tap‐test adjustments, etc.] fall under preprocessing polarity standards. We largely defer any consideration of a display standard.


2011 ◽  
Vol 44 (1) ◽  
pp. 32-42 ◽  
Author(s):  
Thomas Vad ◽  
Wiebke F. C. Sager

Two simple iterative desmearing procedures – the Lake algorithm and the Van Cittert method – have been investigated by introducing different convergence criteria using both synthetic and experimental small-angle neutron scattering data. Implementing appropriate convergence criteria resulted in stable and reliable solutions in correcting resolution errors originating from instrumental smearing,i.e.finite collimation and polychromaticity of the incident beam. Deviations at small momentum transfer for concentrated ensembles of spheres encountered in earlier studies are not observed. Amplification of statistical errors can be reduced by applying a noise filter after desmearing. In most cases investigated, the modified Lake algorithm yields better results with a significantly smaller number of iterations and is, therefore, suitable for automated desmearing of large numbers of data sets.


2017 ◽  
Vol 135 (3) ◽  
pp. 247-252 ◽  
Author(s):  
Luis Antônio Borges ◽  
Plínio da Cunha Leal ◽  
Ed Carlos Rey Moura ◽  
Rioko Kimiko Sakata

ABSTRACT BACKGROUND AND OBJECTIVES: Postoperative analgesia and early recovery are important for hospital discharge. The primary objective of this study was to compare the analgesic effectiveness of perianal infiltration and subarachnoid anesthesia for hemorrhoidectomy. The secondary objective was to compare time to discharge, adverse effects and complications. DESIGN AND SETTING: Randomized, prospective and comparative study at Dr. Mário Gatti Hospital. METHODS: Forty patients aged 18-60, in American Society of Anesthesiologists physical status category 1 or 2, were included. The local group (LG) received local infiltration (0.75% ropivacaine) under general anesthesia; the spinal group (SG) received subarachnoid block (2 ml of 0.5% bupivacaine). Analgesic supplementation consisted of fentanyl for LG and lidocaine for SG. Postoperative pain intensity, sphincter relaxation, lower-limb strength, time to discharge, analgesic dose over one week and adverse effects were assessed. RESULTS: Eleven LG patients (52.4%) required supplementation, but no SG patients. Pain intensity was higher for LG up to 120 min, but there were no differences at 150 or 180 min. There were no differences in the need for paracetamol or tramadol. Times to first analgesic supplementation and hospital discharge were longer for SG. The adverse effects were nausea, dizziness and urinary retention. CONCLUSIONS: Pain intensity was higher in LG than in SG over the first 2 h, but without differences after 150 and 180 min. Time to first supplementation was shorter in LG. There were no differences in doses of paracetamol and tramadol, or in adverse effects. REGISTRATION: ClinicalTrials.gov NCT02839538.


<em>Abstract</em>.—The anadromous Atlantic sturgeon <em>Acipenser oxyrinchus</em> once supported an important commercial fishery throughout its range (northern Florida, USA, to Labrador, Canada). All surviving populations are apparently depleted, presumably due to overfishing, pollution, and dam construction. A complete moratorium on the fishery has been established in U.S. waters. Unfortunately, population status is unknown for nearly all systems. Several 1994–2001 data sets from South Carolina rivers were examined for their potential in development of recruitment (year-class abundance) indices. Because Atlantic sturgeon often begin leaving their natal systems at age 2, after which they occupy other systems and then presumably return to natal areas at sexual maturity several years later, a valid river-specific abundance index must be based on either age0–1 or adult fish. Working with three former commercial Atlantic sturgeon fishermen to collect adults in two rivers during the spring and fall of 1998 resulted in collection of only 39 fish in 13 nominal age-classes. In another river, 2 years of monthly sampling with multipanel, anchored gill nets and otter trawls at eight stations throughout the estuary produced only 31 juvenile Atlantic sturgeon. Neither of these study designs provided adequate sample sizes. However, sampling in a clean-bottom section at the freshwater–brackish water interface of the Edisto River with a modified drift gill net produced large numbers of small Atlantic sturgeon. More than 3,000 juveniles have been collected and tagged since 1994. The 1,331 nominal age-1 Atlantic sturgeon that were captured displayed a distinct bimodal length frequency distribution, supporting the hypothesis that there are both spring and fall spawning events. A period of record drought impeded sampling efforts during a portion of this study. However, when flows and bottom configurations allow nets to be fished at the freshwater–brackish water interface, the gears and methods employed in the Edisto River can produce an age-1 Atlantic sturgeon catch per unit effort that is high enough to be used in estimating relative year-class strength.


2016 ◽  
Vol 39 (11) ◽  
pp. 1477-1501 ◽  
Author(s):  
Victoria Goode ◽  
Nancy Crego ◽  
Michael P. Cary ◽  
Deirdre Thornlow ◽  
Elizabeth Merwin

Researchers need to evaluate the strengths and weaknesses of data sets to choose a secondary data set to use for a health care study. This research method review informs the reader of the major issues necessary for investigators to consider while incorporating secondary data into their repertoire of potential research designs and shows the range of approaches the investigators may take to answer nursing research questions in a variety of context areas. The researcher requires expertise in locating and judging data sets and in the development of complex data management skills for managing large numbers of records. There are important considerations such as firm knowledge of the research question supported by the conceptual framework and the selection of appropriate databases, which guide the researcher in delineating the unit of analysis. Other more complex issues for researchers to consider when conducting secondary data research methods include data access, management and security, and complex variable construction.


2018 ◽  
Vol 09 (01) ◽  
pp. 073-079 ◽  
Author(s):  
Shankar Vallapu ◽  
Nidhi Bidyut Panda ◽  
Navneh Samagh ◽  
Neerja Bharti

ABSTRACT Context: Scalp infiltration and scalp block are being used to manage postcraniotomy pain. Dexmedetomidine has been successfully used as an adjuvant in regional anesthesia. The study was intended to compare whether addition of dexmedetomidine prolonged the duration of analgesia as well as to compare the two techniques. Aims: The primary objective was to assess whether addition of dexmedetomidine to bupivacaine prolonged the duration of analgesia. The secondary objective was to compare between scalp nerve block and scalp infiltration as techniques for pain relief. Settings and Design: The randomized control study was conducted in a tertiary care center from November 2013 to October 2014. Materials and Methods: A total of 150 American Society of Anesthesiologists Physical Status I–II patients, aged 18–70 years undergoing elective craniotomy were included. Patients were randomized into three groups of 50 patients, i.e., Group BI (bupivacaine infiltration), Group BDI (bupivacaine and dexmedetomidine infiltration), and Group BDNB (bupivacaine and dexmedetomidine scalp nerve block). Patient's pain score, pain-free interval, rescue analgesic requirement, and hemodynamic and respiratory parameters were noted for 48 h. Patients were followed up at 1 and 3 months to assess postcraniotomy pain. Results: Pain-free period was significantly longer in Group BDNB than Groups BDI and BI (P < 0.0001) and pain control was better in dexmedetomidine containing groups than in bupivacaine group (BI) (P < 0.0001). The rescue analgesic requirement was significantly lower in Group BDNB and Group BDI compared to Group BI. Conclusion: The addition of dexmedetomidine (1 µg/kg) to bupivacaine prolonged the pain-free period. Scalp nerve block is a superior technique than scalp infiltration.


2002 ◽  
Vol 19 (2) ◽  
pp. 106-122 ◽  
Author(s):  
Einar Ødegård ◽  
Anne Line Bretteville-Jensen ◽  
Astrid Skretting

Einar Ødegård & Anne Line Bretteville-Jensen & Astrid Skretting: The development of drug abuse in Norway in the 1990s This article aims to shed light on the development of drug abuse in Norway during the 1990s. The data come from various different sources, including questionnaire studies as well as other data sets describing the extent of drug abuse in the country. There has been a marked increase in drug abuse during the 1990s. Data from annual youth surveys in 1990 to 1995 indicate that between 8 and 10 per cent of youths aged 15–20 had ever used cannabis, whereas the figure during the latter half of the decade was substantially higher at 18–19 per cent. Surveys in the whole population also point at an increase from 1991 through to 1999: in 1991 the proportion indicating they had ever used cannabis was 8.2%, by 1999 the figure had risen to 12.5%. Furthermore, a simple cohort analysis clearly indicates that large numbers are continuing to use cannabis: the figures are also rising in older age groups. With the growing prevalence of cannabis use in younger age groups we may therefore expect to see increasing numbers of regular and frequent cannabis users in the whole population as well. Drug seizures by the police and customs have increased sharply during the latter half of the 1990s: this applies not only to amphetamine and ecstasy but also cocaine and LSD. This is supported by the results of annual questionnaire surveys among youths, who are reporting a marked increase in the use of these types of drugs. In the early 1990s around 1% of youths in the age group 15–20 said they had ever used amphetamine. This figure remained more or less unchanged through to the mid-1990s. However by the end of the decade around 4% said they had used amphetamine. The data from youth surveys furthermore indicate that there is considerable overlap in the use of amphetamine and ecstasy. In this material the sharpest increase is recorded in the proportion of those indicating they have used both amphetamine and ecstasy. There are several indicators which describe the extent of heroin abuse. All these indicators show that there has been a sharp increase in heroin abuse during the 1990s. A simple mortality analysis suggests that the number of heroin abusers has doubled over the past decade. Drug abuse has also spread markedly both in relation to age groups and geographically: today the problem is by no means limited to any specific age group, nor just to a few major cities.


2019 ◽  
Vol 12 (1) ◽  
pp. 211-236 ◽  
Author(s):  
Frederik Tack ◽  
Alexis Merlaud ◽  
Andreas C. Meier ◽  
Tim Vlemmix ◽  
Thomas Ruhtz ◽  
...  

Abstract. We present an intercomparison study of four airborne imaging DOAS instruments, dedicated to the retrieval and high-resolution mapping of tropospheric nitrogen dioxide (NO2) vertical column densities (VCDs). The AROMAPEX campaign took place in Berlin, Germany, in April 2016 with the primary objective to test and intercompare the performance of experimental airborne imagers. The imaging DOAS instruments were operated simultaneously from two manned aircraft, performing synchronised flights: APEX (VITO–BIRA-IASB) was operated from DLR's DO-228 D-CFFU aircraft at 6.2 km in altitude, while AirMAP (IUP-Bremen), SWING (BIRA-IASB), and SBI (TNO–TU Delft–KNMI) were operated from the FUB Cessna 207T D-EAFU at 3.1 km. Two synchronised flights took place on 21 April 2016. NO2 slant columns were retrieved by applying differential optical absorption spectroscopy (DOAS) in the visible wavelength region and converted to VCDs by the computation of appropriate air mass factors (AMFs). Finally, the NO2 VCDs were georeferenced and mapped at high spatial resolution. For the sake of harmonising the different data sets, efforts were made to agree on a common set of parameter settings, AMF look-up table, and gridding algorithm. The NO2 horizontal distribution, observed by the different DOAS imagers, shows very similar spatial patterns. The NO2 field is dominated by two large plumes related to industrial compounds, crossing the city from west to east. The major highways A100 and A113 are also identified as line sources of NO2. Retrieved NO2 VCDs range between 1×1015 molec cm−2 upwind of the city and 20×1015 molec cm−2 in the dominant plume, with a mean of 7.3±1.8×1015 molec cm−2 for the morning flight and between 1 and 23×1015 molec cm−2 with a mean of 6.0±1.4×1015 molec cm−2 for the afternoon flight. The mean NO2 VCD retrieval errors are in the range of 22 % to 36 % for all sensors. The four data sets are in good agreement with Pearson correlation coefficients better than 0.9, while the linear regression analyses show slopes close to unity and generally small intercepts.


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