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Shift towards mechanization in the municipal solid waste management (MSWM) is aimed at improving health wellbeing of the workers who are manually handling waste. With huge investment and operating costs, proper evaluation and monitoring of the performances of these equipment is essential. Identifying and rating the factors which impact the performance of equipment is the first step towards improving efficiency of a system. This research identifies the critical factors and issues in the operation optimization of refuse compactor vehicles. Interviews with experts and field studies helped in identification of 30 factors which were divided in five categories. The research uses analytical hierarchy process (AHP) for finding out the priority vectors of thus identified factors and categories. The study also highlights equipment selection parameters for the best suited model and make. [ABSTRACT FROM AUTHOR]

The study investigates the surface vibrations generated by a new generation, tri-band hydraulic compactor type V8 from Maschinentechnik Schrode AG (MTS), and a reversible plate compactor type DPU 6055 from Wacker Neuson in close proximity to a low-rise residential building. Compaction works were carried out in three stages, at distances: 15 m, 10 m, and 5 m from the building, and at three depths: 0.4 m, 1.2 m, and 1.8–2.0 m. The research was conducted at one measurement point, located on the outer foundation wall of the building, and at three measurement points located on the ground at distances of 1.25–7.5 m from the building. The study analyses the distribution of peak component particle accelerations at the ground, and peak component particle velocities at the foundation wall of the building as a function of the distance of compactors from the building and the depth of compaction works, as well as the mode of work of hydraulic compactor type V8 from MTS. The study contains the comparison of the permissible vibration levels that are recommended by selected European standards (DIN, BS, VSS, and PL) and an approximate assessment of the impact of vibrations on the technical condition of the residential building. [ABSTRACT FROM AUTHOR]

Ground vibrations generated during compaction activities in close proximity to residential buildings may cause disturbance to people, or even, in some cases damage the buildings. For this reason, it is very important to possess credible information about levels of vibrations generated by different compaction devices. Site compaction works are usually conducted with the use of plate compactors. This study investigates ground vibrations developed by a new generation of rig-mounted hydraulic compactor type V8 from MTS, in the immediate vicinity of a low-rise residential building, located in Ksiezyno, Poland. The research has been conducted at one measurement point, located on an exterior load-bearing wall of the building, and at three measurement points located on the ground at distances 2.5-7.5 m from the building. Compaction works were carried out in two locations at distances 10 m and 15 m from the building, and at three depths: 0.4 m, 1.2 m and 1.9-2.0 m. Measurements of vibration accelerations were carried out using 24-bit LAN-XI data acquisition hardware from Brüel&Kjær, as well as with a set of three low-frequency, seismic piezoelectric accelerometers type 8340 also manufactured by Brüel&Kjær and nine low-frequency piezoelectric accelerometers type 3187D from Dytran. In the course of measurements of the ground acceleration sensors were fixed to mounting bases, secured in the ground by a three-point anchor. In each measurement point data acquisition was carried out in three mutually perpendicular directions. The study analyses the distribution of vibration accelerations in a function of the distance of compactor from the building, the depth of compaction works, as well as the mode of work of hydraulic compactor type V8 manufactured by MTS. The analysis is carried out independently for each of the measurement directions ( x , y , z ). The results presented in the paper can be used to predict approximate safe distance applied in performing the construction activities with the use of this type of compactors. [ABSTRACT FROM AUTHOR]

Aim: To determine the current trends in technological armamentarium and endodontic treatment among Brazilian endodontists. Methods: A total of 279 endodontists answered a web-based survey questionnaire about their region of activity in Brazil and years as a specialist, average number of endodontic cases treated per month, number of visits to complete the treatment, use of rubber dam for isolation, type of irrigant, obturation technique and device used for this purpose, temporary filling materials, and greater difficulty encountered during treatment and technological armamentarium. A descriptive analysis, expressed in terms of frequency and percentage, was performed and the data were correlated using the chi-square test (p<0.05). Results: Most of the respondents had up to 10 years as specialists. More than 50% of endodontists preferred to complete the endodontic treatment in a single visit. Ninety-nine percent of endodontists used rubber dam for isolation. NaOCl was the most widely used irrigant. Most of the respondents associated different techniques for root canal filling. Lateral condensation and Continuous wave of condensation were the isolated technique most reported. Filling devices (thermocompactors) were used by 53% of endodontists. Glass ionomer was the preferred temporary filling material. The answers for the use of technological armamentarium revealing that 94% of endodontists used an apex locator; 67.38% utilized magnification (loupe: 23.66%; microscope: 35.48%; microscope and loupe: 8.24%); 58% reported to digital radiography; and 47.31% used computed tomography as a complementary tool. About mechanized instrumentation, 44.44% endodontists employed rotary and reciprocating files. The difficulties encountered during endodontic treatment were classified as preparation > access > obturation > anesthesia > isolation. Conclusions: Most endodontists have implemented new technologies, such as mechanical instrumentation, apex locators, magnification, digital radiography, computed tomography, ultrasound, and obturation tools, in their clinical practice. [ABSTRACT FROM AUTHOR]

This research contributes to the assessment of on-site fuel consumption and the resulting carbon dioxide emissions due to earthworks-related processes in residential building projects, prior to the start of the construction phase. Several studies have been carried out on this subject, and have demonstrated the considerable environmental impact of earthworks activities in terms of fuel consumption. However, no methods have been proposed to estimate on-site fuel consumption during the planning stage. This paper presents a quantitative method to predict fuel consumption before the construction phase. The calculations were based on information contained in construction project documents and the definition of equipment load factors. Load factors were characterized for the typical equipment that is used in earthworks in residential building projects (excavators, loaders and compactors), taking into considering the type of soil, the type of surface and the duration of use. We also analyzed transport fuel consumption, because of its high impact in terms of pollution. The proposed method was then applied to a case study that illustrated its practical use and benefits. The predictive method can be used as an assessment tool for residential construction projects, to measure the environmental impact in terms of on-site fuel consumption. Consequently, it provides a significant basis for future methods to compare construction projects. [ABSTRACT FROM AUTHOR]

Direct-action and indirect-action vibrators for compaction of silage in container stores were built for experimental trials. Experimental results indicated that during vibrating compaction the grass layer was compacted intensely for 5-10 min. Therefore, vibrators of this type are suggested for compacting grass layers with thicknesses of 0.5-0.6 m. The determination of comparative pressure as a function of vibration frequency showed that the most effective frequency was 43.96 Hz during the direct-action vibrator compaction of grass. This relationship was determined experimentally by measuring the pressure caused by the vibrator and the effective power while compacting the grass mass in a container. The pressure increase coefficient varied over a wide range of 1.5-6.8. It was established that a centrifugal indirect-action vibrator works well to compact chopped maize (a bulk density of up to 730 kg m-3 was achieved) and works to some extent for mixtures of Caucasian goat's rue (Galegaorientalis Lam.) and red clover (Trifoliumpratense L.). This vibrator is not suitable for compacting either pure red clover or pure Caucasian goat's rue because the compacted densities were only 260-350 and 225-280 kg/m3, respectively. Similar studies were performed using a direct-action vibrator, and similar fodder compaction results were obtained. These vibratory silage compaction methods can be recommended for small farms. Vibrating devices are useful on herbaceous plants with large stems (e.g., maize) and are somewhat useful for mixtures including such herbaceous plants when compacting in stores. [ABSTRACT FROM AUTHOR]

Diagnosis is extremely important to ramp up the yield during the integrated circuit manufacturing process. It reduces the time to market and product cost. Limited observability due to test response compaction negatively affects the diagnosis procedure. When multiple chains, mapped to a single compactor, fail, diagnosis becomes extremely difficult. The procedure is even more complicated because when a circuit fails the flush test, not all the patterns are applied. Only a few of the patterns are applied and the observed responses are used to diagnose the faulty chains. In this paper, we have proposed an efficient masking strategy that will be very useful for diagnosis of scan chains when multiple scan chains fail. The proposed strategy uses the redundancy in fault detection by the test patterns and masks scan chains in such a way that enough information can be provided with small increase in test pattern count. A new tester architecture that will select and apply only those patterns having enough information for diagnosis has also been proposed. Diagnostic resolution and first hit index achieved by our method are very close to their ideal values, which validate the applicability of our approach. [ABSTRACT FROM AUTHOR]

In the course of work a new vibrating compactor with single-direction inertial forces according to the authors' innovative license is applied. Examination of possible dependence on substantiation of the new vibrating device parameters is shown. The new single-direction vibrating device for road crushed rock compaction allows decreasing vibration to the machine frame and increasing its working capacity. The new vibrating device's efficiency to 11,7% increases the existing ones. [ABSTRACT FROM AUTHOR]

This paper presents new nonadaptive fault-diagnosis techniques for scan-based designs. They guarantee accurate and time-efficient identification of failing scan cells based on results of convolutional compaction of test responses. The essence of the method is to use a branch-and-bound algorithm to narrow the set of scan cells down to certain sites that are most likely to capture faulty signals. This search is guided by a number of heuristics and self-learned information used to accelerate the diagnosis process for the subsequent test patterns. A variety of experimental results for benchmark circuits, industrial designs, and real fail logs confirm the feasibility of the proposed approach even in the presence of unknown states. The scheme remains consistent with a single test session scenario and allows high-volume in-production diagnosis. [ABSTRACT FROM AUTHOR]

Achieving proper compaction of asphalt pavement is crucial to its longevity and acceptable performance. Laboratory compaction is an essential part of mix design. In order for the mix design process to be effective, laboratory compaction must adequately simulate field compaction. This study used mechanical properties measured with the Superpave shear tester to evaluate field compaction and laboratory compaction. The field compaction consisted of three test sections with different compaction patterns. The laboratory compaction used the Superpave gyratory compactor with adjustments to several parameters. Results of this study indicate that current gyratory protocol produces specimens with significantly different mechanical properties than field cores produced with the same material and compacted to the same air voids. Results also show that adjustments to certain parameters of the gyratory can produce specimens that better simulate the mechanical properties of pavement cores. [ABSTRACT FROM AUTHOR]

Most modified asphalt binders show pseudoplastic characteristics and their viscosity values depend on shear rate. The calculation of compaction temperatures for Superpave gyratory compactors (SGCs) depends on viscosity measurements. Therefore, for modified asphalt binders, it is not possible to calculate the compaction temperatures without including the effect of shear rate in the SGC during viscosity measurements. Prior to this study, no experimental study on the calculation of shear rate in the SGC had been performed. The calculation of the shear rate in the SGC will make it possible to include the effect of shear rate during viscosity measurements. In this study, the shear rate inside the SGC was approximately 490 1/s. Standard error (SE) values of the estimates of shear rate values were calculated by the propagation of error method. The average value for SE was approximately 53 1/s. [ABSTRACT FROM AUTHOR]

Due to increasing traffic levels and vehicle wheel loads, it has become necessary to improve the effectiveness and efficiency of the design of hot mix asphalt (HMA). The Superior Performing Asphalt Pavement (Superpave) mix design and analysis system was introduced for this purpose. The Superpave Gyratory Compactor (SGC) is a vital part of this new mixture design and analysis system. The SGC makes use of a 150-mm- (6-in.) diameter cylindrical mold to produce specimens for design and evaluation under the Superpave system. The objective of this study was to explore the potential for using a 100-mm-(4-in.) diameter mold to produce test specimens in the laboratory. Loose HMA was collected from over 40 paving projects throughout the state of Tennessee. The mixes were tested in the laboratory, and the relative density (%G[sub mm]) of the 150-mm-diameter specimens was statistically compared with that of the 100-mm-diameter specimens. The results of paired t-tests conducted on the data indicate that the difference in %G[sub mm] is statistically significant. However, further analysis of the data demonstrates that the observed difference in %G[sub mm] is smaller than the documented precision of the currently available laboratory test methods used. Thus, it is concluded that the observed difference has no “engineering” significance. Based on these findings, it has been recommended to the Tennessee Department of Transportation (TDOT) that it is feasible to use 100-mm-diameter specimens in lieu of the 150-mm-diameter specimens for quality assessment/quality control (QA/QC) acceptance and verification testing of HMA. It should be noted that this recommendation is limited to mixes with a maximum aggregate size of 25.4 mm (1 in.) or less. [ABSTRACT FROM AUTHOR]

Describes the results of two baler and compactor-related investigations conducted during 1992-2000, and summarizes surveillance data from 1992-1998, which indicated some employers and workers may have been unaware of hazards of the equipment. Risk factors of working with baling equipment; Editorial note from the United States Centers for Disease Control and Prevention.

The arrangement of horizontal stiffeners over the entire height of the "vibratory Christmas tree" is expedient. In compacting soils requiring saturation during compactor operation, the stiffeners should be welded only to the lower portion of the tubular core; this not only increases the effect of the compaction, but also makes it possible to use a less powerful vibratory embedder and the increase the reliability of the apparatus. Further research is required, however, to disseminate recommendations on reducing the number of compactor stiffeners under other soil conditions. [ABSTRACT FROM AUTHOR]