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Theoretical bases of soil movement were developed whereby a drill furrow was formed by an anchor plowshare with an acute angle of soil penetration with spaced structural elements. When the seeding working tool penetrates the soil at the depth of 0.06-0.08 m and the radius of its tine 0.2 m, the speed of movement of soil particles by the tine increases almost linearly on average by 11%, with the coefficient of soil friction against steel being from 0.3 up to 0.6 and the speed of the sowing unit movement - from 1 to 3 m/s. At the same time the speed of soil movement by the tine point and the tine of the seeding working tool exceeds the speed of the sowing unit by 1.6-1.8 times depending on the values of the coefficient of soil friction against steel. The height of the real soil tillage by the tine of the seeding working tool given the same speed range of the sowing unit increases by almost 4 times. The dependency was revealed between the value of the soil layer shift by the seeding working tool from the sowing zone into the inter-row space and the sowing unit speed. When the speed increases from 1 to 3 m/s, the shift increases by 15-32%. The maximum soil movement is observed with the angle of inclination of the side edge of the seeding working tool by 75°. Absolute values of soil movement were within the range of 0.35-0.45 m, which is sufficient to move the required amount of soil into the inter- row space when doing furrow sowing.

Research from the 1980s reported sweep cultivation being a cost-effective component in an integrated system to manage weeds in peanut. Previous weed management research conducted on organic peanut indicated that repeated cultivation with a tine weeder was an effective component in that production system. Studies were conducted in Tifton, GA, from 2014 through 2017 to determine whether tine weeding can be integrated with herbicides in conventional peanut production to supplement herbicides. Experiments evaluated a factorial arrangement of eight herbicide combinations and two levels of cultivation using a tine weeder. Herbicides were labeled rates of ethalfluralin PRE, S-metolachlor PRE, imazapic POST, ethalfluralin PRE + S-metolachlor PRE, ethalfluralin PRE + imazapic POST, S-metolachlor PRE + imazapic POST, ethalfluralin PRE + S-metolachlor PRE + imazapic POST, and a nontreated control. The herbicides chosen were based on knowledge of the weed species composition at the research sites and their common use in peanut. Cultivation regimes were cultivation with a tine weeder (six times at weekly intervals) and a noncultivated control. Benefits of tine weeding supplementing control from herbicides varied according to herbicide and weed species. For example, annual grasses were effectively controlled (88% to 97%) by ethalfluralin or S-metolachlor and did not need cultivation to supplement control provided by the herbicides. However, imazapic alone did not effectively control (54% to 75%) annual grasses and needed supplemental control from cultivation with the tine weeder. Similarly, imazapic effectively controlled (84% to 93%) smallflower morningglory and did not require cultivation to supplement control from the herbicide. However, cultivation with the tine weeder improved smallflower morningglory control (76% to 95%) when supplementing ethalfluralin or S-metolachlor. Peanut yields did not respond to any of the herbicide combinations integrated with cultivation using the tine weeder. During the time period when peanut was cultivated, there was greater total rainfall and more days of rainfall events in 2014 and 2017 compared with the other years. Rainfall and wet soils reduced the performance and weed control benefits of the tine weeder. This highlights the risk of depending on cultivation for weed control.

Pile-soil interaction is considered to be one of the most important problems in the study of the mechanical behaviour of pile foundation. In this paper, the lateral friction resistance and pile-soil relative displacement of bridge piles in deep soft soils are monitored for an extended period by using concrete strain gauges that are embedded in the test pile. Field test results show that both the pile lateral frictional resistance and pile-soil relative displacement increase along with time, while the pile-soil interaction demonstrates a time effect. Therefore, an elastic-viscoplastic constitutive model must be established to better simulate the time-dependent mechanical behaviour of the pile-soil contact. Based on the Goodman model, we developed an elastic-viscoplastic interface constitutive model of the pile-soil interface into the FRIC subroutine through ABAQUS software, which is one of the most commonly used finite element analysis softwares in the world, to simulate a well-recorded pile test in deep soft soils. The calculated pile lateral frictional resistance and pile-soil relative displacement are close to the measured values, and the ability of the interface model to describe the changes in the shear stress-strain of the pile-soil interface along with time is validated., Međudjelovanje odlagališta (jalovine) i tla jedan je od najvažnijih problema kod izučavanja mehaničkih svojstava takvih odlagališta. Praćeno je bočno smicanje te otpor na dodiru mekoga tla i odloženoga materijala unutar njega tijekom vremena. Unutar testnoga odlagališta također su postavljeni betonski blokovi za mjerenje naprezanja. Rezultati su pokazali kako su bočna smicanja između odloženoga materijala i tla ovisna o vremenu. Ta zavisnost modelirana je elastično-viskozno-plastičnim modelom, čime je opisana ovisnost mehaničkih pojava o vremenu. Prikazani model deriviran je iz Goodmanova, te je rutinom (FRIC) opisan u programskome paketu (ABAQUS), koji je ujedno i najčešći program za analizu konačnih elemenata s ovakvom namjenom. Izračunani otpor na bočno smicanje te relativni pomaci u odlagalištu vrlo su slični onima izmjerenim na mjestu eksperimentalnoga testiranja. Također je potvrđena mogućnost predviđanja modelom promjena nastalih zbog naprezanja tijekom vremena.

Mechanical weeding augmented with automation technology should result in highly effective weeding systems. However, the interaction between weeding mechanisms and soil is not well understood. Moreover, soil is highly variable, which makes studying this interaction challenging. The main objective of this research was to develop a method to investigate the effects of mechanical tool-soil interaction on weeding performance for different operating conditions in a controlled environment. Experiments were conducted in an indoor soil bin with loam soil, and the weeding performance was studied using small wooden cylinders as simulated weed plants. The investigations featured a single cylindrical tine and a rotating tine mechanism, vertically oriented and inserted into the soil. The total width of soil disturbance and potential weeding rate were evaluated for the single cylindrical tine at different levels of three operating parameters: tine diameter (6.35, 7.94, and 9.53 mm), working soil depth (25.4, 50.8, and 76.2 mm), and tine speed (0.23 and 0.45 m s-1). Potential weeding rate was examined for the rotating tine mechanism with two operating parameters: working soil depth (25.4 and 76.2 mm) and rotational speed (25, 50, and 100 rpm). Statistical analysis was performed using ANOVA at p < 0.05. A simulation of the rotating tine mechanism was developed that estimated the disturbed area. For the single tine, soil disturbance width was independent of tine speed; however, tine diameter and depth had significant effects, as the width increased with increased levels of these two parameters. All three parameters had significant effects on the potential weeding rate of the single tine, and the rates were observed to increase with higher levels of the parameters. For the rotating tine mechanism, both depth and rotational speed were significant. The potential weeding rate for the rotating tine mechanism was found to increase with higher levels of these parameters. The results showed that although the width of soil disturbance due to a cylindrical tine was affected by the tine diameter and working soil depth, operating parameters such as increased longitudinal and rotational speeds also affected plant disturbance. The percentage of disturbed soil area in the simulation followed similar patterns as the percentage of disturbed plants observed in the experiments. Keywords: Inter-row weeding, Intra-row weeding, Mechanical weeding, Rotating tine mechanism, Soil disturbance, Tine.

Background Today, there is no manufacturer-supplied retrieval tool for the Micra™ pacemaker (Medtronic, Minneapolis, MN, USA); therefore, off-the-shelf catheters have been employed for retrievals. The proximal retrieval feature of the Micra™ can be snared and the device is then retracted from the myocardium, pulling the device through the tricuspid valve. This study characterizes the potential risks of Micra™ nitinol tine engagement with the tricuspid sub-valvular apparatus. Methods Fresh human hearts nonviable for transplant (n = 10) were obtained from our regional organ procurement agency (LifeSource, Minneapolis, MN, USA). Micra™ fixation tines were affixed to a linear force transducer. Tines were then engaged in tricuspid chordae tendineae to conduct a constant velocity tensile test. Each test was run until tines disengaged from the chordae tendineae or until they released from the valve apparatus. Subsequently, biomechanical failure properties of the valve apparatus and isolated chordae tendineae were determined using a series of uniaxial tensile tests. Results There were no chordal ruptures observed during our Micra™ tine extraction testing. Chordal failure required 15.0 times the force of extracting a single engaged tine, and 9.0 times the force of extracting two engaged tines. The uniaxial stresses required for isolated chordal failure averaged 17.4 N/mm2 ; failure strains exceeded 150% resting chordal length. Conclusions The forces required to rupture tricuspid chordae tendineae significantly exceeded the forces potentially imposed on the chordae during Micra™ device retrievals. We conclude that the fixation tines of the Micra™ device are unlikely to damage the tricuspid apparatus during either implant or retrieval.

Subsoiling is primary practice in conservation tillage fields, as it disrupts compacted soil hardpans that restrict crop root growth and water infiltration. Subsoiler with flexible tines presents effective obstacle avoidance and draft force reduction, but the undesired depths, much less than target value, are observed during tillage operation due to the considerable variation in soil resistance. Therefore, an electric-hydraulic control system for subsoiler with flexible tines was developed and a novel method for detecting tillage depth was described. The performance of the electric-hydraulic control system was evaluated in soil bin experiment by the detecting accuracy of the tillage depth and the operation quality (qualified index, distribution uniformity of tillage depths and draft force reduction). The detecting accuracy of the electric-hydraulic control system was determined at target depths of 25 and 30 cm, by testing tillage depths and comparing with manual measurement. The values obtained by the control system differed from manual measurements by less than 3.2% (3.2% at 25 cm; 1.9% at 30 cm), indicating high accuracy. The operation quality of the electric-hydraulic control system was evaluated for the working speeds of 1.4, 2.0, 2.6 km/h at target depth of 30 cm, by testing the tillage depth, draft force obtained with and without the electric-hydraulic control system. Treatments without the electric-hydraulic control system (CP) were five types of constant hydraulic pressure, respectively 2.0 MPa (CP 2.0), 2.5 MPa (CP 2.5), 3.0 MPa (CP 3.0), 3.5 MPa (CP 3.5) and 15 MPa (CP 15). Treatments with the electric-hydraulic control system (AP) were adjustable hydraulic pressure with the range of 2.0–3.5 MPa. Results indicate that flexible tine with AP created more regular cutting cross-section and acquired relatively consistent tillage depth. The qualified indexes of tillage depth (QI) were respectively 97.5%, 98.2%, and 96.7% at the forward speeds of 1.4, 2.0, 2.6 km/h. And mean tillage depths with AP were respectively 29.54, 29.53, 28.13 cm, closely to target depths. The distribution uniformity of tillage depth with AP was better than CP. Furthermore, draft force increased at the area with high soil resistance, flexible tines with AP experienced a relatively more stable rise and obtained draft force reduction of 18.17%, 18.35%, and 25.89% at three forward speeds. The results demonstrate that the developed system can be used to improving the tillage quality for subsoiler with flexible tines.

Equipping tines with the wings increases draft and soil loosening. Wing angles affect tine performance, soil aggregation and remained residue. In this research, conventional wing with no bent plus ...

Successive years of mechanical operations and conservation tillage in Northeast China have made subsoiling necessary, and the tillage depth can be no less than 40 cm. In this paper, a bionic design method was used to reduce subsoiler energy consumption and soil disturbance. The bionic structural elements, i.e., triangular prism (BTP) and partial circular column (BPCC), were inspired by the placoid scale rib structure of shark skin, which has low drag. These elements were then applied to the subsoiler to reduce energy consumption. Six types of bionic subsoilers were designed. Discrete element modeling (DEM) was used to simulate and analyze the interactions of the bionic subsoilers and an ordinary subsoiler (O-S) with the soil. The results showed that bionic subsoilers with a shank and BTP in the horizontal direction of motion (S-T-H) and tines with the BTP parallel to the centerline (T-T) had lower draft requirements and energy consumption than the other designs. The draft requirements and energy consumption of S-T-H subsoilers with different height-to-lateral-rib-spacing (h/s) ratios were then compared. The subsoiler with a bionic element h/s of 0.57 (S-T-H-0.57) had a lower draft requirement (1292.59 N) and a lower total energy requirement (23.48 J) than the other designs. A soil disturbance analysis demonstrated that S-T-H-0.57-T-T (bionic elements arranged in both the shank and tine) provided superior benefits in terms of root growth and improved crop stress resistance. The result is consistent with the mechanical analysis of the riblet, which will be helpful for designing new subsoilers with reduced drag and soil disturbance.

The overall low detachment percentage in citrus mechanical harvesting is a concerning problem. Studies of the effects of tine-shaking frequency and penetrating depth on fruit detachment for citrus canopy-shaker harvesting have not been reported to date. The objective of this study was to examine how tine-shaking frequency and penetrating depth affect fruit detachment based on simulation and pertinent field experiments for a citrus canopy shaker that inserts a row of shaking tines into the tree canopy. According to evaluation of the branch/stem elasticity, density, and fruit detachment force, a cantilevered limb model, including a periodic shaking force, was constructed to simulate the shaking process in citrus canopy shaking. Simulation results demonstrated a positive correlation between the shaking frequency and maximum stress at the fruit end of the stem, and a 5 Hz shaking frequency found to be sufficient for fruit removal. It was also observed that the penetrating depth ensured that, when shaking spot was close to the junction of the limb and stem, the maximum stress increased at the fruit end of the stem. Field trial results agreed with the simulation results, with both simulation and experiments indicating highly significant effects ( p

Tine spacing is a key parameter for the design of a subsoiler and has a significant effect on soil disturbance, which is a critical performance indicator of subsoiling. In this study, a subsoiling model was developed using the discrete element method (DEM). A subsoiling experiment was also conducted in a field with a loamy clay soil to serve the model development and model validations. In both the simulation and experiment, two V-shaped subsoiling tines were investigated at five different tine spacings (300, 350, 400, 450, and 500 mm), a constant working speed (0.83 m s−1) and a constant working depth (300 mm). The results showed that the 400 mm tine spacing resulted in the highest particle forces in the middle and deep soil layers. The height of the unloosened soil between two adjacent subsoilers increased as tine spacing increased. When the tine spacing was varied from 300 to 500 mm, the undisturbed soil height was changed from 100 to 226 mm in the experiment, and from 79 to 170 mm in the modelling. When the tine spacing was 400 mm, the number of soil particles disturbed in the shallow soil layer accounted for 45.6% of the total soil particles disturbed, which was the least among all the tine spacings. Considering the characteristics of soil disturbance, the tine spacing of 400 mm appeared to outperform the other spacings.

Design optimization and online evaluation of work quality of tillage tools help to find optimal balance between effort and result in tillage operation. Currently, usage of laser scanner has become widespread to examine the soil profile after tillage. However, the results are significantly affected by external circumstances in the field such as sunlight, weeds, residual of plant, etc. Therefore, a soil bin test was carried out by using a laser scanner to evaluate the width and the area of the furrow (shape of furrow) created by using four standard chisel plow tines heavy duty, double heart, double heart with wing and duck foot with widths of cut 0.065, 0.135, 0.450, and 0.400 m, respectively at different speeds and depths. MATLAB based computer program was used to estimate soil profile parameters. Lab results were verified in a field test. The field results were evaluated based on geometric shape of the furrow obtained from the soil bin and a model based on Willatt and Willis's approach in predicting the furrow shape. Results show that the width of the furrow increases linearly with depth while the area of the furrow increases quadratically with depth for all tines. An excellent geometric shape of the furrow was obtained from the soil bin for every tine. The furrow shape is triangle for heavy duty and double heart tines, while it is triangle plus trapezoidal shape for double heart with wings and duck foot tines. Willatt and Willis's equation related to the width of the furrow shows a good agreement for heavy duty and double heart tines at shallow depth.

During an earthquake, structures are generally excited to multiple ground motion components: two orthogonal horizontal components and one vertical component. However, the interaction of the deformations along two principal orthogonal directions in the presence of various levels of axial force in columns in post elastic range can be successfully captured if nonlinear dynamic analysis can be carried out using the bidirectional hysteresis model. On the other hand, the seismic codes prescribed simple combination rules to capture this effect in an equivalent sense even without consideration of axial force in columns. Though these rules may be valid in the elastic range, they may not be applicable in the post-elastic range as mentioned in a few seismic codes. Surprisingly, these codes did not specify any user-friendly provision needed by design offices. Hence, the applicability and efficacy of these rules in the post-elastic range is needed to be compared with that obtained from detailed nonlinear tine history analysis under orthogonal pair of bidirectional ground motions obtained from a number of chosen seismic acceleration data for performance-based design. In this study, idealized low-rise buildings with small, medium, and long periods were investigated, considering the presence of axial force in columns. Most of the current design codes and standards suggest that the addition of response of 30% of ground motion in other direction if added to the response of unidirectional ground motion in the considered direction of analysis or the resultant responses obtained by square root of sum of square from the unidirectional analyses carried out separately in both principal directions (referred as SRSS response) may predict the response with reasonable accuracy. The results obtained from the current study makes an attempt to exhibit the trends of post elastic range response for the structures. Further, it shows that seismic codes options significantly underestimate the post-elastic range seismic demand though they are proved to be adequate to predict elastic range response. This paper may prove helpful in improving code provisions.

This study aimed to evaluate the ability of the response surface methodology (RSM) approach to predict the tractive performance of an agricultural tractor during semi-deep tillage operations. The studied parameters of tractor performance, including slippage (S), drawbar power (DP) and traction efficiency (TE), were affected by two different types of tillage tool (paraplow and subsoiler), three different levels of operating depth (30, 40 and 50 cm), and four different levels of forward speed (1.8, 2.3, 2.9 and 3.5 km h−1). Tractors drove a vertical load at two levels (225 kg and no weight) in four replications, forming a total of 192 datapoints. Field test results showed that all variables except vertical load, and different combinations of this and other variables, were effective for the S, DP and TE. Increments in speed and depth resulted in an increase and decrease in S and TE, respectively. Additionally, the RSM approach displayed changes in slippage, drawbar power and traction efficiency, resulting from alterations in tine type, depth, speed and vertical load at 3D views, with high accuracy due to the graph’s surfaces, with many small pixels. The RSM model predicted the slippage as 6.75%, drawbar power as 2.23 kW and traction efficiency as 82.91% at the optimal state for the paraplow tine, with an operating depth of 30 cm, forward speed of 2.07 km h−1 and a vertical load of 0.01 kg.

Wheat (Triticum aestivum) is planted widely in the Western Cape of South Africa in conservation agriculture systems. Although most producers rely on tine openers to establish wheat, the interest in...

The choice of the method of basic cultivation must be differentiated, considering zonal soil and climatic conditions and local peculiarities of the fields. Chisel tillage refers to soil conservation technologies, and chisel tools provide low-power and, if it is necessary, differential loosened soil, the accumulation, preservation and rational use of soil moisture that is relevant in the arid climate. The authors designed the combined chisel working implements RANCHO, ROPA, plow-cultivator. The traction resistances of the working tools were studied strain-gauge method. The unified equation of traction resistance chisel working was developed. The resistance of tine, chisel, additional equipment on the tine and the dynamics of the chiseling were introduced. The resistance of the chisel was determind by pressure from the soil on its surface. If the speed of machine-tractor aggregate will increase from 1 to 3 m/s then traction resistance of the working implements ROPA will rise by 26-29 percent, plow-cultivator - by 21-23 and classic mould-board plough - by 35 percent due to more significant influence of the dynamic component during moving mould-board plough in the undisturbed soil. The plowing work by the plow-cultivator in comparison with mould-board plough provides more depth of soil loosening (0.38 m when 0.15 m real tillage and 0.2 m in control variant) at comparable energy consumption.

Flax harvesting consists of serial technological processes: pulling, separation of seed bolls from stalks, stalks spreading out, turning during a rest, picking up of them and baling in large packages, loading, and transportation. One of the most important operations is seed balls separation from stalks. Determination of parameter of intensity of flex balls combing by deseeder operation is a little studied. Parameter of intensity of a separation doesn't show clearly its dependence on design features and an operating mode of the unit. The authors considered this relation by the example of the comb deseeder which has different tines on a ridge with accidentally decreasing spacing towards the end. The existing deseeders do not provide qualitative combings of flax stalks. Therefore, theoretical and pilot researches of the ridge comb deseeder were conducted. The program and a technique of researches of the comb deseeder were developed. The theoretical basics of intensity of combing by the comb deseeder are covered. The various factors influence damageability of stalks: geometrical parameters of tines, number of at the same time operating combs, sequence of combing, ratio of tines speeds and gripping conveyor. Characteristics of a combed layer, a flax maturing level, the weight-average values of efficiency of single influence belong to the factors influencing intensity of combing. In the flax harvesters LK-4A and LKV-4A with increase in frequency of the comb deseeder to 2.87 rpm and speeds of the gripping conveyor from 1.54 to 1.58 meter per second the intensity decreased up to 3.02 tine per centimeter, and combing purity increased up to 98 percent. So, intensity 3.02 tine per centimeter should be considered as minimum admissible, and combing purity should be increased no more than by 2 percent.

To determine whether the position of the medial clamp tine during syndesmotic reduction affected reduction accuracy.Prospective cohort.Urban Level 1 trauma center.Seventy-two patients with operatively treated syndesmotic injuries.Patients underwent operative fixation of their ankle syndesmotic injuries using reduction forceps. The position of the medial clamp tine was then recorded with intraoperative fluoroscopy. Malreduction rates were then assessed with bilateral ankle computerized tomography.Fibular position within the incisura was measured with respect to the uninjured side to determine whether a malreduction had occurred. Malreductions were then analyzed for associations with injury pattern, patient demographics, and the location of the medial clamp tine.A statistically significant association was found between medial clamp position and sagittal plane syndesmosis malreduction. In reference to anterior fibular translation, there was a 0% malreduction rate in the 18 patients where the clamp tine was placed in the anterior third, a 19.4% malreduction rate in the middle third, and 60% malreduction rate in the posterior third (P = 0.006). In reference to posterior fibular translation, there was a 11.1% malreduction when clamp placement was in the anterior third, a 16.1% malreduction rate in the middle third, and 60% malreduction rate in the posterior third (P = 0.062). There were no significant associations between medial clamp position and coronal plane malreductions (overcompression or undercompression) (P = 1).When using reduction forceps for syndesmotic reduction, the position of the medial clamp tine can be highly variable. The angle created with off-axis syndesmotic clamping is likely a major culprit in iatrogenic malreduction. Sagittal plane malreduction appears to be highly sensitive to clamp obliquity, which is directly related to the medial clamp tine placement. Based on these data, we recommend placing the medial clamp tine in the anterior third of the tibial line on the lateral view to minimize malreduction risk.Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: The management of complex proximal humerus fractures (Neer’s type III, IV and fracture dislocation) is complicated. There are various treatment modalities available for proximal humerus fractures. We have designed and indigenously manufactured new plate called “SINGLE TINE PROXIMAL HUMERAL T-PLATE (3.5 mm)” for fractures of proximal humerus .The aim of this study was to examine the clinical outcome of complex proximal humeral fractures treated surgically with single tine T-plate. Materials and Methods: This is retrospective observational study included 25 patients who underwent open reduction and internal fixation with single tine T plate for proximal humerus fractures in between 2010 and 2013. . All patients were evaluated using point system of Neer’s shoulder evaluation system. Results: Mean age of the patient 47.12 years (range 22-60 years). All the fractures united with a mean duration of 14 weeks (range 10 weeks to 18 weeks). As per Neer‟s score we achieved excellent or satisfactory results in 21 out of 25 i.e. 84%. The mean Neer‟s score was 85.2 (range 64-94). We had unsatisfactory to poor result in 4 out of 25 cases (16%). (Table 1) Complications were seen in 3 cases (12%). One case of superficial wound infection and two cases of screw loosening. Conclusion: Single tine T-plate is a good alternative implant for treating complex fracture and fracture dislocation of proximal humerus .It is cost effective, and easy to use. The single tine T-plate offers good support against varus mal-reduction. Primary bone grafting is a powerful tool in managing complex fractures/ fracture-dislocation of proximal humerus.

Inferior vena cava filters are important tools used to help prevent life-threatening pulmonary embolisms in hospitalized patients with contraindications to pharmacological prophylactic anticoagulation. This is a case report of a patient who had an inferior vena cava filter placed after a traumatic subdural hematoma. He made a complete recovery but was lost to follow-up until he presented 1825 days after filter deployment with abdominal pain discovered to be from penetration of the filter tines outside the lumen and into adjacent structures. We describe a case complicated by fibrotic tine entrapment with penetration to surrounding structures and discuss the technical approach used to free and eventually remove the long-standing filter.

In this study, artificial neural networks (ANNs) were used to predict the draft force of a rigid tine chisel cultivator. The factorial experiment based on the randomized complete block design (RCBD) was used to obtain the required data and to determine the factors affecting the draft force. The draft force of the chisel cultivator was measured using a three-point hitch dynamometer and data were collected using a DT800 datalogger. A recurrent back-propagation multilayer network was selected to predict the draft force of the cultivator. The gradient descent algorithm with momentum, Levenberg–Marquardt algorithm, and scaled conjugate gradient descent algorithm were used for network training. The tangent sigmoid transfer function was the activation functions in the layers. The draft force was predicted based on the tillage depth, soil moisture content, soil cone index, and forward speed. The results showed that the developed ANNs with two hidden layers (24 and 26 neurons in the first and second layers, respectively) with the use of the scaled conjugate gradient descent algorithm outperformed the networks developed with other algorithms. The average simulation accuracy and the correlation coefficient for the prediction of draft force of a chisel cultivator were 99.83% and 0.9445, respectively. The linear regression model had a much lower accuracy and correlation coefficient for predicting the draft force compared to the ANNs.

Due to the increasingly severe soil compaction and plough pan thickening prevalent in agricultural practice, an increase in operating energy consumption and a decrease in crop growth has been observed. This paper aims to solve the problem of heavy tillage resistance by using riblet structures extracted from shark scales in the design a biomimetic shark-inspired (BioS) subsoiler. To produce better quality work, the design parameters of the BioS subsoiler, including the ratio of the riblet height to the riblet spacing h/s, the riblet height h, and the internal friction angle α, were considered, and a mechanical analysis of the relationship between the BioS subsoiler and the soil was performed to evaluate tillage resistance, total energy consumption and soil disturbance. The minimum tillage resistance and energy consumption of the shank and tine were achieved with an h of 5 mm and h/s of 0.57 obtained from the simulation results. Then, the parametrically optimized BioS subsoilers were fabricated and used to perform field experiments at different tillage speeds. The effects of subsoiling with BioS subsoilers and with an ordinary subsoiler (O–S) on the soil moisture, root morphology and crop yield were also discussed. The results showed that the BioS subsoiler would be helpful to increase the root absorption capacity of water and nutrients, which promote crop growth and increase the crop yield.

Inter tines coupling spring constant $(k_{c})$ influences the eigenfrequencies, effective spring constant $(k_{eff)}$ and sensitivity of the quartz tuning fork (QTF). We have investigated the effect of coupling spring constant $(k_{c})$ on eigenfrequencies, effective spring constant $(k_{eff)}$ and sensitivity using analytical and simulation methods. The aim of study is to obtain an optimal design for the QTF having cantilever beam as the basic element with flexible base and enhanced sensitivity. The simulation and analytical results suggest that by reducing the coupling spring constant (kc), the effective spring constant $(k_{eff)}$ can be reduce and the sensitivity of tuning fork can be enhanced.

Endoscopic radiofrequency ablation has gained interest for treating abdominal tumors. The radiofrequency ablation electrode geometry largely determines the size and shape of the ablation zone. Mismatch between the ablation zone and tumor shapes leads to reoccurrence of the cancer. Recently, work has been published regarding a novel deployable multi-tine electrode for endoscopic radiofrequency ablation. The prior work developed a thermal ablation model to predict the ablation zone surrounding an electrode and a systematic optimization of the electrode shape to treat a specific tumor shape. The purpose of this work is to validate the thermal ablation model through experiments in a tissue phantom that changes color at ablation temperatures. The experiments highlight the importance of thermal tissue damage in finite element modeling. Thermal induced changes in tissue properties, if not accounted for in finite element modeling, can lead to significant overprediction of the expected ablation zone surrounding an electrode.

Weeding is critical to eliminate non-native plants that compete with main crops and adversely affect their production quality and quantity. Numerous prototypes exist for inter-row weeding but very limited for intra-row weed eradication. This study developed a tractor drawn integrated inter- and intra-row weeding (IIIRW) system for field crops. Active rotary tines were used for intra-row weeding and passive tines for inter-row weeding. Optimum operational configurations were obtained with rigorous repeated soil bin experiments, and developed system was evaluated for three growing seasons (2017–19) in field grown maize (Zea mays L.) and pigeon pea (Cajanus cajan (L.) Millsp.) crops. Optimum ratios of intra-row tine rotary speed to forward speed (u/v) were in the ranges of 0.8–1.3 that lead to weed mortality of 88.4 % (Buried: 8.5 %, Uprooted: 79.9 %), negligible intact weeds, and plant damage (Pd) within 6 %. Sole inter-row weeding operation resulted up to 78.1 % of weed mortality (Buried: 18.1 %, Uprooted: 60.0 %) and negligible Pd. Overall weed mortality with the IIIRW system was 92.8 % (Buried: 9.5 %, Uprooted: 83.3 %) in maize and 84.1 % (Buried: 7.6 %, Uprooted: 76.5 %) in pigeon pea crops. Results suggest suitability of the IIIRW system for a range of similar crops for field capacity in ranges of 0.22–0.26 ha/h at recommended operating speeds within 0.50–0.56 m/s. The IIIRW system requires a single prime mover and could be potentially economical and efficient technology for field weeding operations.

The goal of this article is to experimentally study how the vibrational acceleration spreads along the branch shaken by PVC tine, steel tine, and nylon tine for citrus canopy shaking harvesting and to compare the difference. PVC tine and steel tine have potential to be used as shaking rod for citrus canopy shaking harvesting. Nylon tine is a commonly used shaking rod. A tractor-mounted canopy shaker was developed to do the trial. The shaking frequency was set at 2.5 and 5 Hz. Experimental results showed that the vibrational acceleration at the shaking spot is not the highest. Spreading from shaking spot to the stem, it increases evidently. When spreading from stems of the outside subbranch to stems of the nearest inside subbranch, its average decrease percentage is 42%. The overall vibrational acceleration of shaking at 5 Hz is 1.85 times as high as shaking at 2.5 Hz. The overall vibrational acceleration exerted by straight PVC tine and steel tine is 1.77 and 1.97 times as high as that exerted by straight nylon tine, respectively. It is indicated that replacing nylon tine with steel tine or PVC tine helps remove the fruits inside the canopy. Replacing with steel tine is more effective than with PVC tine.

The objective of this work was to assess the influence of the row cleaner attack angle, the gap between discs, the working depth of a narrow tine and the strip tillage machine's working speed on tractor fuel consumption and on greenhouse effect-related CO2 gas emissions into the environment. This research was carried out by changing the row cleaner disc attack angle from 10.0° to 22.5°, the gap between discs from 105 to 135 mm, the working depth from 0 to 200 mm, and the working speed from 1.4 to 3.1 m s−1 in 44 different scenarios. The working speed of the strip tillage machine and the working depth of the narrow tine had the greatest influence on the hourly fuel consumption. The results indicate that increasing the working depth from 0 to 200 mm increases the hourly tractor fuel consumption from 10.3 to 24.3% depending on the working speed. An analysis of the experimental scenarios indicates that the lowest fuel consumption and CO2 emissions per hectare were achieved at a working speed of 2.5 m s−1. The greenhouse effect-related CO2 gas emissions were highest in scenarios with a working speed of 1.4 m s−1. CO2 emissions from tractors increased approximately 20% on average with a working depth increase from 0 to 200 mm. The attack angle of row cleaner discs 10.0°, gap between row cleaner discs 105 mm, working speed 2.5 m s−1, strip width 135 mm were the most optimal parameters for lowest fuel consumption and CO2 emissions from tractor not depending on the working depth of narrow tine.

The objective of the present work was to develop and evaluate aeration machine for turfgrass to make under Egyptian condition. The aeration machine was evaluated versus two holes density (24 and 48 hole/m2), two hollow tine diameters (2.5 and 3 cm), three average depths of aeration (4, 6 and 8 cm) and four forward speeds (2, 2.7, 3.6 and 4 km/h). After 7 days from aeration operation the results showed that the lower bulk density and penetration resistance values was 0.960 g/cm3 and 154 kPa, respectivaly opposite it the higher porosity and void ratio values were 65.09% and 1.865, respectively at 48 hole/m2 holes density, 3 cm tine diameter, 8 cm depth of hole and forward speed 2 km/h comparing with control 1.271 g/cm3, 337 kPa, 53.79% and 1.164 for density, penetration resistance, porosity and void ratio, respectively. The higher actual field capacity was (0.941 fed/h) at 24 hole/m2 holes density, 2.5 cm tine diameter, 4 cm depth of hole and forward speed 4 km/h. The lower energy required was 16.223 kw.h/fed, at 24 hole/m2 holes density, 2.5 cm tine diameter, 4 cm depth of hole and forward speed 4 km/h.

To reduce soil-tool adhesion followed by an improvement in draft force, many attempts have been made on the surface modification of moldboard ploughs by applying plastic coatings to them. Like moldboards, furrowers may also show adherence to soil according to its physical condition. This research aimed at draft force improvement of furrowers using surface coatings. Due to the self-scouring ability and low frictional characteristics of ultra high molecular weight polyethylene (UHMW-PE), a narrow metal furrower has been coated with the plastic. For comparison, a steel tine equal in shape and dimension to the plastic-coated tine has been built. The tines were designed like the furrowers and were tested for draft force in a linear soil bin filled with heavy clay soil. Each experiment was repeated three times over a depth of 20 cm with two different compactions and gravimetric moisture content of 4% and 18% dry based. The average draft force value of the polythene coated tine was significantly lower at both moisture levels. In high compacted soil with 18% MC (gravimetric moisture content), the draft force of the UHMW-PE coated tine measured 29% less than that of the steel tine. In conclusion it has been found that the modification to the furrower tines by UHMW-PE coating can reduce draft force significantly.

Mechanization of fruit and nut harvesting is becoming increasingly important because of a significant rise in the cost of manual harvesting. This work proposes a progressive analytical approach for the design and optimization of a citrus canopy shaker harvesting machine. The approach was formulated using finite element (FE) methods to find the optimum design parameters of the machine. The design parameters were defined in terms of a configuration (or stiffness) of shaking rods and two operating parameters: shaking frequency and shaking amplitude. The formulated methodology consists of determining the properties of wood, statistical modeling of the tree limbs, developing mechanistic models, and performing optimization using FE simulations. The proposed methodology employs the response surface methodology or surrogate models to quantify the objective functions, and Pareto-optimal search techniques to find the optimum designs. Three sets of machine parameters were proposed in this study to minimize tree damage and maximize fruit removal. These optimal parameters were proposed based on the configuration and distribution of limbs and fruits in a medium-size citrus tree. The optimized tine configuration of the middle and bottom section of the canopy shaker consists of a solid rod made of polyamide reinforced with 50% long glass fibers and a hollow tube made of hardened steel in a 3:1 ratio by length. These tines, when vibrating at a high frequency of 7.8 Hz and low amplitude of 3.81 to 5.08 cm (1.5 to 2 in.) and a low frequency of 3 to 3.5Â Hz and high amplitude of 13.9 to 15.2 cm (5.5 to 6 in.), provide a 25% to 30% reduction in damage to the tree limbs in the bottom and middle zones of the tree. Similarly, changes to the top sections of the canopy shaker with another set of optimized tine configurations resulted in a 40% to 45% reduction in the damage to the limbs of the top section of the tree canopy. The optimized tine configuration, thus proposed for the top section of the canopy shaker, is made of a solid rod of polyamide reinforced with 60% long glass fibers and vibrates at a frequency of 6.5 to 7.5 Hz with an amplitude of 7.6 to 8.9 cm (3 to 3.5 in.).

Tillage is one of the most important and expensive operations in agriculture. A crucial measure in soil protection and tillage quality is assessment of soil roughness. The objective of the current study is to utilize spectral analysis while investigating the effects of tillage with a heavy duty tine at work depths of 5, 10, 15, 20 cm and speeds of 4, 7, 10, 13 km h −1 on the soil cross-section. In order to pick a practically appropriate longitudinal step size, a high-resolution measurement was performed. The conditions of this measurement included 4 km h −1 speed with 10 cm working depth. Spectral analysis of selected soil cross-section parameters was performed to assess a cutting frequency below which the significant spectral contents were located. Such an analysis led to the conclusion on a practical longitudinal resolution of 5 cm. This measure is more reliable than picking several cross-section measurements at random. Influence of different tillage depths and speeds on selected soil cross-section parameters was investigated. It was observed that the volumes of disturbed and loosened soil were mainly influenced by the tillage depth while the furrow was more affected by the work speed.

The paper presents research results on the effect of cutting depth and speed on the resultant force tilt angle and location of its application point on a flexible tine ended with a cultivator point. The studies were carried out in field conditions in sandy clay with the gravimetric moisture of 11.2% and volumetric density of 1470 kg·m−3. Tines whose flexibility coefficient was 0.0061; 0.0711; 0.0953 and 0.1406 m·kN−1 were used. It was found out that that the resultant force tilt angle raises at the increase of the cutting speed and drops at the increase of depth but this angle and its gradient at the increase of the cutting depth grow along with the decrease of the flexibility coefficient of tines. The increase of the cutting speed and depth causes the decrease of both the distance of the resultant force application point on the tool from the bottom of a furrow and a proportion of this parameter to the cutting depth. The courses of the distance of the resultant force application point on the tool from the bottom of a furrow and courses of proportion of this parameter to the cutting depth as the function of cutting do not differ significantly for tines with higher flexibility coefficients while for the most rigid tine values of these parameters and their gradients are higher. All obtained courses of the analysed values as a function of depth and cutting speed were described with regression equations.