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A field experiment was carried out to evaluate the effect of leveling and tillage equipment on the soil bulk density and the growth and production of maize. Three landscaping types of equipment, namely laser, pelvic, and grader equipment, and three tillage equipment, namely moldboard plow, chisel plow, and no-till farming system. Soil bulk density, practical productivity, plant height, weight of 100 seeds, number of seeds per ear, and the yield of maize were measured. The results can be summarized as follows: The interaction between the pelvic leveling equipment and the no-till farming system was superior in obtaining the lowest soil bulk density, while the interaction between the laser leveling equipment and chisel plow was superior in obtaining the highest plant height, the highest weight of 100 seeds stood 36.70 g, the highest number Seeds per ear stood 371.30 seeds per ear and the highest yield of the plant stood 6.36 tons ha-1 compared to the other interventions. [ABSTRACT FROM AUTHOR]

This paper is concerned with the possibility of applying modern non-contact methods for assessing the wear as a result of tribological interaction between working bodies and the soil. An original method for wear testing using the test space discretization based on the 3D scanning technology was employed. A localized volumetric wear coefficient was proposed, allowing for wear analysis and improving the accuracy of the Holm-Archard model. The coefficient of local volumetric wear shows the influence of the nominal shape and the slip trajectory of the abrasive particle along the elementary surface on the intensity of wear. At local volumetric wear coefficient > 0.3, this factor determines the intensity of surface wear. Volumetric wear characteristics are the basis for prediction of wear consequences for different materials and techniques of reinforcement of working surfaces, subject to intensive wear in abrasive soil mass. The reliability of the study is confirmed by the comparison with the mass method for wear assessment and the results of the application of the proposed method for different conditions of abrasive wear of operating parts. [ABSTRACT FROM AUTHOR]

The article examines the development of woodworking industries in Kharkiv region, the situation of artisans, their income and everyday life. The impact of the new economic policy on production volumes is determined. Cooperage, carpentry, carpentry, and art products were studied. The transformation and development of handicrafts is identified and studied. The tax system that influenced woodworking handicraft production is considered. We made our own expedition to the workshop of a famous master who used the experience of his ancestors in the manufacture of products. The technology of production of wooden products characteristic of Kharkiv region is studied, and the industry concentration is determined. The connection of cooperage with other branches of agriculture is indicated. The authors studied the work of carpenters and described traditional housing of the hata-sena type and the gradual transformation in the Ukrainian village into a hata-sena-hata dwelling. We paid attention to the manufacture of tools (pitchforks, rakes), household items (troughs, mortars, ladles, buckets, etc.). The life of a rural family was directly connected with woodworking crafts, wood products were in demand, so the masters of this business increased significantly during the NEP period. The authors described the range of chiseled products, consisting of bowls, glasses, salt shakers, rolling pins. Birch, maple, hornbeam, and ash were used to make crafts. In the Slobozhansky Museum of local lore, at the exhibition "hall of ethnography", the authors studied wooden products and production technology of the period of the new economic policy in Kharkiv region. [ABSTRACT FROM AUTHOR]

Drilling two different materials in a layer, or stack-up, is being practiced widely in the aerospace industry to minimize critical dimension mismatch and error in the subsequent assembly process, but the compatibility of the drill to compensate the widely differing properties of composite is still a major challenge to the industry. In this paper, the effect of customized twist drill geometry and drilling parameters are being investigated based on the thrust force signature generated during the drilling of CFRP/Al7075-T6. Based on ANOVA, it is found that the maximum thrust force for both CFRP and Al7075-T6 are highly dependent on the feed rate. Through the analysis of maximum thrust force, supported by hole diameter error, hole surface roughness, and chip formation, it is found that the optimum tool parameters selection includes a helix angle of 30◦, primary clearance angle of 6 ◦, point angle of 130◦, chisel edge angle of 30◦, speed of 2600 rev/min and feed rate of 0.05 mm/rev. The optimum parameters obtained in this study are benchmarked against existing industry practice of the capability to produce higher hole quality and efficiency, which is set at 2600 rev/min for speed and 0.1 mm/rev for feed rate. [ABSTRACT FROM AUTHOR]

Fresh investigation carried out in the southern part of Bonaigarh subdivision of Sundargarh district, Odisha, brought to light some very significant dimensions of lithic celt production sites located in the village Sulabhdih and its surrounding region. Not only valley floors and foothills, but slope and top of hills were also utilized for mass production of semi-finished celts, particularly chisels and adzes. Our study suggests that mass production of these craft specialized semi-finished items were probably intended for not only local use at settlement areas where these were further modified into finished products, but these were presumably transported to different regions of highland Odisha and also beyond through trade and/or exchange network. Although no datable material could be recovered during our limited section scrapping, keeping in view available dates from within Odisha, Jharkhand and Karnataka, these sites are tentatively dated to the beginning of second millennium BCE. The present paper intends to bring out some new aspects of celt production in the southern part of Bonaigarh subdivision, hitherto unknown in Odisha and other parts of the sub-continent. [ABSTRACT FROM AUTHOR]

This paper takes Qingdao Jiaozhou Bay subsea tunnel project as the research object to study the relationship among rock mechanical parameters and chiseling specific energy and abrasion performance. SPSS22 was used to analyze the correlation between the parameters. The results show that except for the low correlation with Poisson ratio, all the other parameters in the single factor correlation analysis have high R. By taking the chiseling specific energy and abrasion performance as dependent variables, taking each mechanical parameter as an independent variable, multifactor regression analysis and stepwise multifactor fitting were carried out; it was concluded that the abrasion performance was highly correlated with uniaxial compressive strength and integrity coefficient, and the chiseling specific energy is highly correlated with uniaxial compressive strength and softening coefficient. In the process of verifying the fitting models, it is found that, under the influence of quartz vein and microfissure in the specimens, the chiseling specific energy formula has a higher fitting value, while the fitting formula of abrasion performance has a higher reference value for the specimens in the study area. [ABSTRACT FROM AUTHOR]

The northern Canadian Cordillera (NCC) of northwestern Canada is segmented by several margin-parallel, right-lateral, strike-slip faults that accumulated several hundred kilometers of displacement between the Late Cretaceous and the Eocene. The depth extent of these faults, notably the Tintina fault (TF), has important implications for the tectonic assemblage and evolution of NCC lithospheric mantle, but geophysical models and geochemical data remain inconclusive. Using a recent three-dimensional P-wave seismic velocity model, we resolved a series of sharp (-10 km) P-wave velocity contrasts (-4%) at uppermost mantle depths beneath the surface trace of the TF. Seismic anisotropy data that represent upper-mantle fabrics revealed similar changes in the orientation and magnitude of anisotropy in the vicinity of the TF. These data suggest that the TF is a lithospheric-scale shear zone. After restoration of 430 km of right-lateral displacement along the TF, fast P-wave anomalies align with the outline of the North American craton margin. We propose the fast anomaly structure currently located in eastern Alaska represents a fragment of the Mackenzie craton that was chiseled and displaced to the northwest by the TF between the Late Cretaceous and the Eocene. A second cratonic fragment currently located in the southern NCC may be associated with the Cassiar terrane at upper-mantle depth. These observations provide the first evidence that large lithospheric-scale shear zones cut through refractory mantle and produce major lateral displacement of cratonic mantle material within cordilleras worldwide. [ABSTRACT FROM AUTHOR]

No-tillage system production in Argentina requires high traffic intensities, for example, 50 to 65 Mg km-1 ha-1. Due to these traffic intensities, continuously and successively applied, the soils are compacted. One of the frequently utilized techniques for management of topsoil and subsoil compaction is chiseling. The objectives of this work were: a) to evaluate the effect of vertical tillage on the physical properties of a Typic Argiudol soil from northeastern Rolling Pampa Region at Argentina and b) to quantify the power required by a chisel plow working in one and two depth levels on a soil under no-tillage. Three treatments were applied: T1) control plot (unloosened soil), T2) loosened with one chisel plow pass at a 0.25m deep range, and T3) loosened with two chisel passes, the first at 0.15m and the second at 0.25m. The following variables were measured: cone Index (CI), soil water content, (SWC), tractor slip (TS) and power and draft force (PD). The main results and conclusions showed: a) The CI values on the two deep tillage treatments were statistically different (P < 0.01) from that of the control plot, up to 300 mm and b) the chisel plow working in two depth ranges (T3) could significantly increase the specific resistance and drawbar power. This means that vertical tillage carried out in two chisel passes (T3) was, from an energy point of view, less efficient than one single pass (T2). [ABSTRACT FROM AUTHOR]

Aramid fiber–reinforced plastic (AFRP) composites have been widely used in automotive, aerospace, and defense industries. The common AFRP drilling process tends to cause damage to the composite structures which subsequently affects their fatigue lives and in-service performance. Understanding the mechanism of cutting force generation is crucial in controlling the cutting process for achieving desired hole quality and machining accuracy. This study proposes a novel mechanistic model considering both the cutting action and the extrusion action of the chisel edge. For the first time, the extrusion force generated by the chisel edge has been considered as a rigid wedge penetrating into an elastic half space based on the Hertz contact theory. The total thrust force in AFRP drilling is divided into three components: (i) thrust force generated by the cutting lips, (ii) thrust force generated by the chisel edge cutting action, and (iii) extrusion force generated by the chisel edge extrusion action. The proposed model was then validated by experiments and data was compared with the case where extrusion was not considered. The results show that our novel mechanistic model can provide a more accurate thrust force prediction. The average error of our model was 2.54% against the experimental data, whereas the error seen in conventional model without accounting extrusion was 8.22%. This suggests that the chisel edge extrusion plays a significant part in the drilling of AFRP and hence confirms the necessity of considering extrusion in establishing the associated mechanistic model. [ABSTRACT FROM AUTHOR]

The chisel-edge axial rake angle has an important effect on the processing performance of helical point micro-drills. In this research, the mathematical modeling for the spiral groove, helical flank, and cross-shaped chisel edge are conducted, and then three types of helical point micro-drills, each having a thinned chisel edge with an unequal axial rake angle, are designed and fabricated. Then, the finite element simulations and processing experiments of micro-drilling are performed separately, and the thrust force, torque, chip morphology, tool wear, and micro-hole machining quality are measured and evaluated. With the rise of the axial rake angle of the chisel edge, the curling degree of the chips and the thrust force were found to decrease owing to the increase of the rake angle along the inner cutting edge. The angle between the tool axis and chip axis was found to gradually decrease due to the reduction of the rake angle gradient along the cutting edge. Additionally, the thickness and width of the uncut chip of the inner cutting edge were found to increase, bringing about the rise in the torque. The wear degree of the micro-drills with a 0° axial rake angle (Type II) was the smallest due to their medium thrust force and torque, and a better micro-hole entrance morphology and minimum roundness were obtained. When drilling to the 30th hole, compared with the micro-drills with a − 10° axial rake angle (Type I) and 10° axial rake angle (Type III), the chisel edge maximum wear width of Type II (δ = 0°) was respectively reduced by 82.43% and 19.69%, and the micro-hole roundness respectively decreased by 26.7% and 11.33%. The thrust force of Type I (δ = − 10°) was the largest, so it caused greater tool wear and poorer micro-hole quality. The larger torque and lower rigidity of the inner cutting edge of Type III (δ = 10°) led to poorer drilling performance. Thus, helical point micro-drills having the 0° chisel edge axial rake angle are suitable for drilling 304 austenitic stainless steel. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article analyses ground stone discoveries from the late neolithic site of Pericei located in north-west of Romania, in Șimleu Depression. Combined characteristics of chisels and adzes in working process are discussed along with their context, especially those connected to stone working: the layer, dwellings and pebble agglomerations. We conclude that Pericei was a production center for stone chisels, appeared to supply the demand that until then was satisfied by Suplac/Porț site that continued to produce ground stone tools for a longer period.

A new design of the bottom unload non-bucket rotor (BUNBR) for an open-pit excavator with additional end chisels is described. It makes it possible not only to increase the output due to additional end chisels on the shell, but also to reduce the slope stress due to soil cutting from top to bottom on the working face and creation of a wider berm in comparison with the existing constructions of rotary working bodies. The method of calculation of soil cutting with the end chisel in the form of a two-sided skewed wedge is presented. Based on the spatial scheme of the cutting force components acting in the soil cutting, the expressions in coordinate axes for soil resistance to cutting with the end chisel were determined. These results were used to derive expressions for the tangential and end (lateral) cutting force exerted by a two-sided skewed wedge mounted at the BUNBR end side and to determine the total soil cutting force simultaneously exerted by the corner and end chisels. [ABSTRACT FROM AUTHOR]

Chisel edge thinning can effectively improve the drilling performance of austenitic stainless steel. Four kinds of helical point micro-drills, each with a thinned chisel edge of a distinct length, are fabricated based on the mathematics models of the micro-drill by using a six-axis computer numerical control tool grinder. Micro-drilling experiments on 304 stainless steel are conducted. Drilling performance is evaluated according to the measured and observed micro-hole machining quality, chip morphology, thrust force, and tool wear of the micro-drill tip. With a decrease in the chisel edge length, the micro-holes drilled using thinned micro-drills have small entrance burrs, roundness errors, and regular shapes, which are attributed to an increase in self-centering capability. Owing to increased equivalent chip thickness and different directions of chip flow, micro-drills with thinned chisel edge can generate more small-size chips and improve chip breaking. In addition, the inner cutting edge with a positive rake angle replaces the chisel edge with a negative rake angle to cut the workpiece, significantly reducing the chip curl, thrust force, and tool wear of micro-drills. However, helical point micro-drills with critical chisel edge lengths by thinning exhibit less thrust force and tool wear than do helical point micro-drills with no chisel edge because of the increase in the uncut chip width of the micro-drill. Thus, with the selected parameter range, the optimal helical point micro-drill is the micro-drill with a specific chisel edge length by thinning to improve drilling performance. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a twist drill was used to drill carbon fiber reinforced polymer composite (CFRP) materials to study the influence of the chisel edge drilling behavior on delamination at different parameters. The test results show that a high spindle speed is beneficial to the chisel edge to remove the material when the chisel edge is about to drill the bottom of the plate, and the chisel edge drilling behavior has important effect on delamination. In order to reduce the impact of chisel edge on delamination, three kinds of step drills (different ratio of primary drill bit diameter to secondary drill bit diameter (k)) were designed to drill CFRP at different cutting parameters. The method of combining theory with practice is used to analyze delamination of step drill, and to optimize the step drill structure. Experimental results demonstrates that the hole entry quality of the step drills are better than that of the twist drill. k has great impacts on hole exit delamination. The step drill, k is about 0.5, can achieve the best hole exit quality under the large processing parameters, therefore it's suitable for drilling of CFRP. [ABSTRACT FROM AUTHOR]

Cross-shaped chisel edge thinning is an effective method to improve the drilling performance of non-coaxial helical flank micro-drill. In order to study the effect of the cross-shaped chisel edge on drilling performance, the mathematical model of cross-shaped chisel edge is proposed. The rake angle, lip inclination angle, uncut chip thickness, and uncut chip width are calculated by MATLAB software. Finite element models of four kinds of micro-drills with a different thinned chisel edge are established using DEFORM-3D software, and micro-drilling simulations on 304 austenitic stainless steel are carried out. The simulation results show that with a decrease in chisel edge length, the drilling force, tool temperature, tool wear, and curl degree of the chip are clearly reduced. However, for micro-drill without chisel edge, the torque and tool temperature are larger than other micro-drills, and string chips are generated during the drilling process. Furthermore, the non-coaxial helical flank micro-drill with an optimal cross-shaped chisel edge is manufactured by a six-axis CNC grinding machine, and the measurement results indicate that the geometrical parameters meet the designed values. At last, the micro-drill with an optimal cross-shaped chisel edge has a satisfactory drilling performance by the micro-drilling experiment. [ABSTRACT FROM AUTHOR]

After the harvest of winter wheat, the tensile force, cross section of loosened soil and specific resistance of soil were measured on a loamy soil plot. During the comparative measurements, 3 blades were used with chisel width of 20 mm, 40 mm and 75 mm. In case of all blades, the measurements were carried out at the depth of 100, 200 and 300 mm. In the course of measurements, the standards of blades were attached in a measuring frame on six-component hinge with connected tensometric sensor. The selected blades were developed for a new type of tiller destined for primary cultivation of soil. Moreover, in case of a blade equipped by chisel there were used side wings of a width of 110, 150 and 200 mm for tillage into a depth of 100 mm. It was found that the width of blade chisels did not have a statistically significant effect on the values of specific resistance of soil during the soil tillage. At all widths of blade chisels, a trend of an increase in specific resistance of soil was recorded at growing recess into the soil. [ABSTRACT FROM AUTHOR]

This paper presents a cutter partition-based tool orientation optimization algorithm that can identify and eliminate both local and rear gouging in five-axis machining. This algorithm is developed to generate smooth gouge-free tool paths for arbitrary free-form surfaces machined by general Automatically Programmed Tools (APT) cutters. The algorithm involves an iterative process of cutter projection to compute the gouge-free cutter positions. During each iteration, the cutter partition method is used to classify the cutting portion of the cutter, which in turn determines the gouging condition. Based on the classification, the algorithm applies an optimal gouge-avoidance strategy to minimize the size of tool orientation and position changes. The proposed algorithm can handle the combination of local and rear gouging (either separately or simultaneously), guarantee front edge cutting (avoiding damage to the cutter and surface), ensure a safety clearance between the rear edge of the cutter and the machined surface, and achieve minimal interruption to tool orientation and position from gouge avoidance. Simulation and cutting experiments confirm the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Documenta Praehistorica is the property of Documenta Praehistorica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A tool's axial rotation influences the geometric properties of a tool mark. The larger the axial rotation angle, the larger the compression of structural details like striations. This complicates comparing tool marks at different axial rotations. Using chisels, tool marks were made from 0° to 75° axial rotation and compared using an automated approach Baiker et al. [10]. In addition, a 3D topographic surface of a chisel was obtained to generate virtual tool marks and to test whether the axial rotation angle of a mark could be predicted. After examination of the tool mark and chisel data-sets it was observed that marks lose information with increasing rotation due to the change in relative distance between geometrical details on the tool and the disappearance of smaller details. The similarity and repeatability were high for comparisons between marks with no difference in axial rotation, but decreasing with increased rotation angle from 0° to 75°. With an increasing difference in the rotation angles, the tool marks had to be corrected to account for the different compression factors between them. For compression up to 7.5%, this was obtained automatically by the tool mark alignment method. For larger compression, manually re-sizing the marks to the uncompressed widths at 0° rotation before the alignment was found suitable for successfully comparing even large differences in axial rotation. The similarity and repeatability were decreasing however, with increasing degree of re-sizing. The quality was assessed by determining the similarity at different detail levels within a tool mark. With an axial rotation up to 75°, tool marks were found to reliably represent structural details down to 100μm. The similarity of structural details below 100μm was dependent on the angle, with the highest similarity at small rotation angles and the lowest similarity at large rotation angles. Filtering to remove the details below 100μm lead to consistently higher similarity between tool marks at all angles and allowed for a comparison of marks up to 75° axial rotation. Finally, generated virtual tool mark profiles with an axial rotation were compared to experimental tool marks. The similarity between virtual and experimental tool marks remained high up to 60° rotation after which it decreased due to the loss in quality in both marks. Predicting the rotation angle is possible under certain conditions up to 45° rotation with an accuracy of 2.667±0.577° rotation. [ABSTRACT FROM AUTHOR]

It is important to evaluate the effect of tillage practices on carbon flow and economic parameters in order to better understand soil carbon sequestration and mitigation of carbon release into the atmosphere, and to increase income for farmers. A 2-year field experiment was conducted in a winter wheat-summer corn rotation system on dryland farmland on the Loess Plateau in Northwest China with four treatments; zero tillage with straw mulching (zero tillage), rotary tillage with straw incorporation (rotary tillage), chisel plow tillage with straw incorporation (chisel plow), and conventional mouldboard plow tillage without crop straw (conventional tillage). Results showed that zero tillage reduced carbon emissions, mainly through reduction of emissions from tillage practices, and served as a net carbon sink, as did rotary tillage and chisel plow, while conventional tillage served as a net carbon source. Specifically, zero tillage reduced carbon emissions from farm inputs by 168.8 and 75.0 kg C ha −1 yr −1 compared with conventional tillage and rotary tillage (or chisel plow), respectively. The difference in annual rate of carbon sequestration between 2013 and 2015 was 1.21-fold higher with zero tillage than with conventional tillage, suggesting zero tillage released less CO 2 and was therefore better able to mitigate against global warming. Chisel plow significantly ( P < 0.05) improved net return values by 10.7%–63.2% in the 2013-14 cropping year and by 12.8%–93.7% in the 2014–15 cropping year, respectively when compared to other tillage treatments. Zero tillage was the most effective method for reducing carbon inputs and increasing carbon sequestration, and chisel plow was the best option for provision of economic parameters on dryland farmland in this region. Therefore, the application of conservation (zero, rotary and chisel plow) tillage could be a C-smart and effective economic agricultural practice for winter wheat-summer corn ecosystems under rain fed condition. [ABSTRACT FROM AUTHOR]

One of modern way of the heat treatment process of agricultural tools such as chisels or tines is FEM modelling. FEM models needs the accurate boundary conditions for successful solution. Specific heat capacity and thermal conductivity are important parameters for the design of the physical properties of heat treatment. These parameters are used for the formation of the temperature field during the cooling process at the heat treatment. More accurate parameters allow you to better estimate the final microstructure in the entire cross-section of the material. Specific heat capacity and thermal conductivity are known from material sheets, but they are stated as constant values. This is the reason why this work is focused on the determination of specific heat capacity and thermal conductivity of steel during the quenching. For the experiment in this work was chosen material 25CrMo4. The values of specific heat capacity and thermal conductivity were determined by comparing the experimentally measured cooling curves and cooling curves generated by the mathematical model. The dependences of specific heat capacity and thermal conductivity were compared in temperature, so that the relationships of cooling curves were statistically significant under alfa level 0.05. [ABSTRACT FROM AUTHOR]

A field experiments were conducted using a chisel plow in silty loam soil at Agricultural Research Station of Garmat Ali in 2017. Three different levels of forward speed (0.65, 0.87 and 1.65 m sec-1) and plowing depth (10, 20 and 30 cm) were used to study their effect on energy utilization efficiency, specific energy, plowed soil volume rate and soil pulverization ratio. The results showed that increasing the forward speed from 0.55 to 1.35 m sec-1, the specific energy, plowed soil volume rate and soil pulverization ratio were increased by 139.43%, 85.10% and 51.72%, respectively, while decreased the energy utilization efficiency by 30.04%. Increasing plowing depth from 10 to 30 cm led to increasing the energy utilization efficiency and the plowed soil volume rate by 34.30% and 87.38%, respectively. In contrast, the soil pulverization ratio and the specific energy decreased by 45.83% and 19.86%, respectively. The interaction between the forward speed and the plowing depth had a significant effect on all parameters in this study. [ABSTRACT FROM AUTHOR]

In the past, several experimental and analytical studies have been conducted aimed towards predicting the critical thrust force responsible for delamination at the hole exit during drilling. Among these analytical models, few take into account the coupling between bending and stretching often observed in multi-directional (MD) laminates with an un-symmetrical stacking sequence considering the presence of an elliptical crack. In addition, in these analytical models, the tool/composite contact region is modeled without taking into account the chisel edge effect. In the present study, a unique analytical model for critical thrust force prediction has been proposed that explicitly accounts for the effect of the chisel and cutting edges. The interaction zone (composite/chisel edge and composite/principal cutting edge) has been modeled using classical lamination plate theory (CLPT) and linear elastic fracture mechanics (LEFM) principles. In addition, a comparison between the proposed analytical model predictions and experimental results from quasi-static punch tests accompanied with different X-ray tomography observations led to choosing the accurate loading profile developed during drilling. [ABSTRACT FROM AUTHOR]

The ability to vary primary tillage timing between fall and spring for sugarbeet production could benefit producers by providing flexibility for when field work occurs and may allow earlier planting in the spring. This study was conducted to evaluate the effects of strip (ST) and conventional (CT) tillage conducted in the spring and fall under various N supply levels on sugarbeet production in the northwest U.S. Experimental treatments included tillage time (fall and spring), tillage system (moldboard plow [MP], chisel plow [CP] and strip tillage [ST]), and N supply (5 levels including a control). The study was conducted in Kimberly, ID in 2008 and 2009 on a Portneuf silt loam. Within each year and tillage type, estimated recoverable sucrose (ERS) and root yields were not different between fall and spring tillage timings. These data suggest that sugarbeet growers in the northwest U.S. have flexibility in timing their tillage practices across various tillage systems. [ABSTRACT FROM AUTHOR]

The continuous use of tillage equipment without variation of the work depth can lead to soil compression problems. This study aimed to evaluate the spatial variability of soil resistance to penetration (RP) in a yellow ultisol profile in different tillage systems and tractor-equipment speeds. The experiment was carried out at the Agricultural Sciences Campus - UNIVASF, Petrolina- PE, Brazil, in randomized blocks with split plot with four repetitions. The treatments consisted of five tillage systems applied to the plots: without the first soil preparation, tandem grid and moldboard plow, 0.56 m offset grid discs, 0.61 m off-set grid disc plus tandem grid and chisel plow. For the subplots, the speeds of the tractor-equipment used were: 2.45 km h-1 (L1), 3.88 km h-1 (L2), 5.72 km h-1 (L3) and 6.50 km h-1 (H1). For the soil data collection and the RP determination, an electronic penetrometer was used, determining the sample profile moisture. Data analysis was carried out based on geostatistics and isoline maps. It can be verified the operationarea of the active organs of the equipment, the zoning of compacted areas (RP) and the RP levels of the studied profile. The lower RP was obtained when the tandem grid plus the chisel plow was used. [ABSTRACT FROM AUTHOR]

Soil is an extremely abrasive environment that causes a change in the part dimension of agricultural tools like as chisels or ploughshares. Dry rubber wheel test according to ASTM G65 is one of standard to wear testing. For this test is used Ottawa sand (SiO2 particles) which have a spherical shape. The actual soil contains sand, but also particles of other minerals with higher or lower abrasion than sand. This article is focuses on identifying the abrasive particles in the soil by electron microscopy with EDS analysis. The results should be used for mixing the abrasive particles to the rubber wheel test, but also to identify the mineral composition of the soil profile. The aim of the research is closer to the real test of wear on the field and laboratory tests on the device with a rubber disc. Results shown that the soil contents alumina oxide particles with high hardness or silumina complex chemical composition with sharp shape. The ratio of amount these abrasive particles in the soil is influenced by geological position in earth and this ratio of particle amount influence wear rate in actual soil. [ABSTRACT FROM AUTHOR]

Proper selection and correct use of machinery in agriculture must be understood as a component of a process which aims to optimize crop yield and to make a more efficient use of resources. The objective of this study was the assessment of different chisel plow body arrangements using different settings of the most important operating parameters for tillage work in order to optimize energy consumption for vertical tillage. The influence of different operating parameters of tillage tools on the performance in cultivation practice must be considered before applying deep plowing for a more efficient use of energy. The parameters considered in this study were: 1) working depth based in the critical depth theory 2) position and spacing of chisels 3) number of bodies and 4) usage of wings or sweeps. The field work was divided into five different groups of chisel arrangements and a control group. The field experiment was performed using an articulated chisel plow prototype allowing the setting of those operation parameters, an integral force transducer with three extended octagonal rings to measure the draft forces (kN) and a perfilometer to determine the cross-sectional area of soil disturbed (m2) in terms of specific resistance of the soil (kN/m2) were used. The total energy consumption for disturbed soil area (MJ ha-1) was determined assessing the area under the curve generated by draft force using Matlab R2012b V software. The results shown that the best arrangement for vertical deep tillage was the one integrated by four shallow chisels working at 0.20 m and two deep winged chisel at 0.30 m when compared with the integral arrangements of seven chisels working at the same depth of 0.30 m. A significant savings up to 23.9% in the total energy consumed, 40% in power demand and 38.7% in the specific soil resistance was obtained with an increase of 7.35% in disturbed soil area. [ABSTRACT FROM AUTHOR]

A microcontroller based instrumentation package was designed, developed and mounted on an 81 kW Massey Ferguson 399 (MF-399) tractor. This package continuously measures and monitors various performance parameters of the tractor and implement. These parameters were: actual and theoretical forward speed, slip, fuel consumption and draft force. The package comprised of four components: power supply, transducers, data acquisition, and display unit. Power was taken from the tractor battery. The minimum resolution of the rear wheel and fifth wheel are 0.010213 and 0.002199 m per pulse respectively. The average calibration constant for fuel consumption was 0.00004545 liter per pulse. The data acquisition system was capable of scanning the data at 0.1 s intervals. The system performed well during the field operations and the results obtained showed that the accuracies of the transducers were acceptable. [ABSTRACT FROM AUTHOR]

Soil compaction can be detrimental to plant growth and production, and can threaten the long-term sustainability of no-tillage systems. Chisel plowing is one of the alternatives for ameliorating soil compaction. The objective of this research was to evaluate chiseling for compaction amelioration of a Typic Hapludox under long-term no-tillage system. To achieve this objective, a soil resistance to penetration 2D transect was measured in two adjacent plots in a kaolinitic-oxidic oxisol. Half of the area was a long-term no-tillage system, while the other half was the same no-tillage system with the addition of one chisel plowing operation. The evaluations were performed after chiseling in 2009 and a year after the operation, in 2010.The chisel plow was effective in reducing soil compaction to the depth of 0.40 m (1.312 ft).The frequency of soil resistance to penetration values between 2,000 and 4,000 kPa (290.075 and 580.150 psi) was greater for the no-tillage system when compared to the chisel plow. The no-tillage plot had 70% of the soil resistance values between 2,000 and 4,000 kPa (290.075 and 580.150 psi), while the chisel plow plot had 57.3% of the soil resistance values below 2,000 kPa (290.075 psi). Logistic regression was effective in generating a probability map of susceptibility to compaction for the soil layer under evaluation. [ABSTRACT FROM AUTHOR]

This study presents a dynamic-induced direct-shear model to investigate the dynamic triggering of frictional slip on simulated granular gouges. An incident P-wave is generated as a shear load and a normal stress is constantly applied on the gouge layer. The shear stress accumulates in the incident stage and the frictional slip occurs in the slip stage without the effect of the reflected wave. The experimental results show a non-uniform shear stress distribution along the gouge layer, which may be induced by a shear load induced torque and by normal stress vibration along the layer. The shear stress at the trailing edge strongly affects the frictional slip along the P-wave loading direction, while the rebound stress at the leading edge propagates along the opposite direction. The frictional slip is triggered when the maximum shear stress at the trailing edge reaches a critical value. The normal stress influences the maximum shear stress at the trailing edge, the maximum slip displacement and the slip velocity. The advantages and the limitations of this model are discussed at the end. [ABSTRACT FROM AUTHOR]

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This case report discusses osteotome sinus floor elevation (OSFE) and immediate placement in 2 stages in severely resorbed alveolar bone height in which multiple implant placement is not otherwise feasible due to a lack of initial stability. The first implant placed using OSFE without bone grafting prepares the adjacent resorbed sites for further implant placement in the sinus areas, which allows for better initial stability and early functional loading. This process avoids the conventional extensive lateral approach for sinus lifting and bone grafting procedures even in extremely resorbed alveolar bone. [ABSTRACT FROM AUTHOR]

Abstract: The origin of more than 90% in service pipeline failures is attributed to the presence of stress concentration areas such as defects in forms of gouges, dents, or when these defects are present together. These defects are provoked by external factors interferences, for instance by excavation machines. The influence of the dent depth on the burst pressure of the pipeline was evaluated. An approach based on a simple local strain criterion has been proposed to predict the damage and the failure of evaluated dented pipe. To validate a purely empirical rule, which specifies that a critical depth dent is equal to 10% of outside diameter of the pipeline, a series of mechanical tests (denting tests and burst tests) were conducted. Finite element analysis used in order to compare the numerical and experimental results. Experimental results showed that a single dent did not affect the burst pressure of the investigated specimens; therefore the rule of a critical depth of dent equal to 10% was found very conservative. [Copyright &y& Elsevier]

Farm machinery wheeling is considered a major source of soil compaction. The use of chisel plow can minimize such effects, but the chisel can cause subsurface compaction. The aim of this study was to evaluate the effect of traffic and is present below the compaction layer thought compressive parameters of soil. The treatments investigated were: no-tillage, no-tillage with additional traffic (traffic intensity of 24.67Mg km ha-1), no-tillage chiseling recent implanted, no-tillage with additional traffic and chiseling recent implanted. For the density, void ratio, preconsolidation pressure and coefficient of compressibility determination in the layers 0.0-0.10m, 0.10-0.20m, 0.20-0.30m and 0.30 to 0.40m samples were collected. The treatment no-tillage showed the lowest load support capacity and greater susceptibility to compaction. The traffic intensity of 24.67Mg km ha-1 increased bulk density and decreased void ratio until 0.30m depth. The chisel plow did not affect the preconsolidation pressure and coefficient of compressibility of soil layer below the line of action of the chisel tip. [ABSTRACT FROM AUTHOR]

The alternative soil tillage (CP) and mouldboard ploughing (MP) was applied for five years on a heavy soil under Slovenian agro-ecological conditions. The measurements of horizontal resistance with horizontal penetrometer were performed at 15, 25 and 35 cm layer depth on 375 m long experimental parcel. In the 15 cm layer significant lower resistance was detected in MP15 (40.98 Ncm-2) than in CP15 (45.10 Ncm-2), while in 25 cm layer higher resistance was measured in CP25 (122.47 Ncm-2) than in MP25 (91.66 Ncm-2). The measurement of CO2 emissions from the soil were carried out by the LC pro+ device during the whole year in hourly interval. Significant lower emissions (31.934 Mg/ha day in January and 52.464 Mg/ha day in June) were measured in the CP in comparison with the MP (112.527 Mg/ha day in January and 144.460 Mg/ha day in June). [ABSTRACT FROM AUTHOR]

The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP) in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface using a pneumatic chisel and using through bolts and nuts were the most effective techniques. Also, Sprayed GFRP applied on 3 sides (U-shaped) was found to be more effective than 2-sided Sprayed GFRP in shear strengthening. Sprayed GFRP increased the shear load-carrying capacity and energy absorption capacities of RC beams. It was found that the load-carrying capacity of strengthened RC beams was related to an effective strain of applied Sprayed GFRP. This strain was related to Sprayed GFRP configuration and the technique used to enhance the concrete-FRP bond. Finally, an equation was proposed to calculate the contribution of Sprayed GFRP in the shear strength of an RC beam. [ABSTRACT FROM AUTHOR]

Metallographical studies of a steel chisel excavated from the early Iron Age megalithic site at Mahurjhari, Vidarbha, Maharashtra were carried out. The analysis shows clear evidence of technological advance in the form of hardening and quenching followed by tempering treatment in addition to the knowledge of steeling as early as 900 BC. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work is to assess a gouge defect in a pipe submitted to internal pressure. To do that a method based on failure assessment diagram and more precisely on a Modified Notch Failure Assessment Diagram (NMFAD) which has been proposed as a mesofracture approach. The safety factor has been determine under conservative conditions i.e. for a X52 pipe steel having a relatively low fracture toughness and a severe gouge defect with high aspect ratio and high constraint. In addition a mesofracture approach of the fracture toughness transferability problem has been proposed. The crack (K–T) methodology has been modifying to create the (Kρ –Tef ) two parameters fracture resistance criterion. [Copyright &y& Elsevier]

Abstract: Different natural stone quarries are visited for collection of stone samples, determination of geological conditions, specifications and operational conditions of the chain saw machines and recording machine cutting performance with a data acquisition system. The samples are tested with a linear cutting test rig using chisel-type cutting tools with 0°, 15°, 30° and 45° sideways angles at different depths of cut and tool spacings, to determine stone cuttability, cutting characteristics of chain saw machines and effect of unsymmetric and symmetric sideways angles and different cutting patterns on cutting performance (tool forces, specific energy, optimum cutting geometry). A deterministic model is suggested for predicting performance of chain saw machines using the results of linear stone cutting experiments, and the laws of kinematics. The results of experimental studies and in-situ investigations indicate that the cutting action of chain saw machines can be successfully simulated by linear cutting experiments and the suggested model is proven, though requiring some additional study, to be a useful and reliable tool for selection, design, and performance prediction and optimization of chain saw machines. [Copyright &y& Elsevier]

Motivation Accounting for biological and practical requirements in DNA sequence design often results in challenging optimization problems. Current software solutions are problem-specific and hard to combine. Results DNA Chisel is an easy-to-use, easy-to-extend sequence optimization framework allowing to freely define and combine optimization specifications via Python scripts or Genbank annotations. Availability and implementation The framework is available as a web application (https://cuba.genomefoundry.org/sculpt%5fa%5fsequence) or open-source Python library (see at https://github.com/Edinburgh-Genome-Foundry/DNAChisel for code and documentation). Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

Abstract: This study analyzes the temperature profile along the cutting edges of a drill and describes how the temperature on the chisel edge can exceed the temperature on the primary cutting edges. A finite element model predicts the temperature distribution in the drill, where the heat flux loads applied to the finite element model are determined from analytical equations. The model for the heat flux loads considers both the heat generated on the shear plane and the heat generated on the rake face of the tool to determine the amount of heat flowing into the tool on each segment of the cutting edges. Contrary to the conventional belief that the maximum temperature occurs near the outer corner of the drill, the model predicts that the maximum temperature occurs on the chisel edge, which is consistent with experimental measurements of the temperature profile. [Copyright &y& Elsevier]

Drilling-induced delamination often occurs both at the entrance and the exit of the workpiece during drilling of composite material. Investigators have studied analytically and experimentally that delamination in drilling can be correlated to the thrust force of the drill. With a pre-drilled pilot hole, the delamination can be reduced significantly. Early reference reported models of drilling-induced delamination, however, the effect of chisel edge length and pilot hole diameter on delamination is rarely discussed. The optimal range of chisel edge length with respect to drill diameter is derived in this paper. [Copyright &y& Elsevier]