The Dynamically Embedded Plate Anchor: Results From an Experimental and Numerical Study

2013 ◽  
Author(s):  
Conleth D. O’Loughlin ◽  
Anthony P. Blake ◽  
Dong Wang ◽  
Christophe Gaudin ◽  
Mark F. Randolph
Keyword(s):  
Experimental Work ◽  
Field Experiments ◽  
Numerical Study ◽  
Field Tests ◽  
Dry Weight ◽  
Numerical Work ◽  
Geotechnical Centrifuge ◽  
Plate Anchor ◽  
Plate Anchors ◽  
The Impact

Dynamically embedded plate anchors are rocket shaped anchors that penetrate to a target depth in the seabed by the kinetic energy obtained through free-fall. After embedment the central shaft is retrieved leaving the anchor flukes vertically embedded in the seabed. The flukes constitute the load bearing element as a plate anchor. This paper provides an overview of an experimental and numerical study undertaken to provide the first performance data for this anchor concept. The experimental work includes geotechnical centrifuge modelling and field tests using three different reduced anchor scales, whereas the numerical work focused on investigating anchor capacity for a rage of geometries, embedment depths and seabed conditions. The experimental work indicates that expected tip embedments are in the range 2 to 3.3 times the anchor length and depend on the impact velocity, anchor mass and shear strength of the soil. As with other plate anchors, the anchor needs to key before maximum capacity can be mobilised. Both the centrifuge and field experiments show that this keying and pullout behaviour is typical of other vertically installed plate anchors, where the main issue is the loss in embedment during keying. Both the experimental and numerical studies showed that the capacity of the DEPLA is much higher than that of other dynamically installed anchors with capacities up to 40 times the dry weight of the plate and plate bearing capacity factors of about 15.

scholarly journals Alternative Control of Phragmidium rubi-idaei Infecting Two Rubus Species

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1452
Author(s):  
Raluca-Maria Pârlici ◽  
Aurel Maxim ◽  
Stefania Mirela Mang ◽  
Ippolito Camele ◽  
Lucia Mihalescu ◽  
...  
Keyword(s):  
Organic Farming ◽  
Plant Pathogens ◽  
Field Experiments ◽  
Control Sample ◽  
Field Tests ◽  
In Vitro Tests ◽  
Rust Disease ◽  
Conidia Germination ◽  
The Impact

Organic berry plantations have been gaining popularity among farmers during recent years. Even so, farmers experience serious challenges in disease control management, which is a concern in organic farming. Phragmidiumrubi-idaei (DC) P. Karst is the pathogen responsible for blackberry and raspberry rust disease, one of the most present and active diseases in plantations. The antifungal certified products found on the organic farming market offer the opportunity for an efficient control strategy over plant pathogens in fruit shrub plantations. In this study, 5 natural based products—namely Altosan, Mimox, Canelys, Zitron, and Zeolite—were tested for their fungistatic effect over P. rubi-idaei. The experiments were carried out under laboratory conditions, performing observations over the impact of organic products, used at different concentration levels, on rust conidia germination. Moreover, field experiments were conducted in order to evaluate the efficiency of different treatments for rust control on raspberry (‘Polka’, ‘Veten’ and ‘Heritage’) and blackberry (‘Thorn Free’, ‘Chester’ and ‘Loch Ness’) varieties. Data analysis based on ANOVA tests showed significant differences between the tested variants and the control sample at p < 0.001. Furthermore, LSD test confirmed differences between all substances tested (p < 0.005). The natural products Canelys (formulated with cinnamon) and Zytron (based on citrus extract) have proven the highest inhibitory capacity for conidia germination during in vitro tests registering values of 80.42% and 78.34%, respectively. The same high inhibitory rates against rust pathogen were kept also in the field tests using the same two natural-based products mentioned earlier. In addition, outcomes from this study demonstrated that Zeolite is not recommended for raspberry or blackberry rust control.

PFC-2D Numerical Study of the Influence of Passive Vibration Assisted Rotary Drilling Tool (pVARD) on Drilling Performance Enhancement

2018 ◽  
Author(s):  
Abourawi Alwaar ◽  
Abdelsalam N. Abugharara ◽  
Stephen D. Butt
Keyword(s):  
Experimental Work ◽  
Performance Enhancement ◽  
Numerical Study ◽  
Particle Flow Code ◽  
Laboratory Work ◽  
Depth Of Cut ◽  
Rotary Drilling ◽  
Drilling Tool ◽  
Numerical Work ◽  
Drilling Performance

The objective of this work is to evaluate the influence of the implementing the downhole Passive Vibration Assisting Rotary Drilling (pVARD) Tool on enhancing drilling performance using a numerical study utilizing a Particle Flow Code (PFC-2D). The work is comprised of a numerical study of a simulation using the PFC-2D on an experimental work described in ARMA 15-492 (Rana et al, 2015). The numerical study was performed to validate the experimental work following the steps, procedure, and conditions performed in the laboratory work. The numerical study of the laboratory work involves not only the evaluation of drilling rate of penetration (ROP), but it also includes the Depth of Cut (DOC) of the bit cutters and the Mechanical Specific Energy (MSE). This numerical work also includes comparison study of drilling performance under various configurations of the pVARD tool, which represents a controlled downhole vibration against the rigid drilling configuration that represents the conventional rotary drilling. The pVARD configurations involves pVARD low spring compliance, medium spring compliance, and high spring compliance. The drilling output parameters of DOC, MSE, and ROP are then studied and analyzed in all pVARD and non-pVARD configurations. Likewise of the experimental work, the result of the numerical simulation approves the experimental work and it indicates the positive effect of utilizing the downhole pVARD on improving ROP. The drilling performance enhancement is also supported by the DOC and the MSE result.

Experiment on the Anti-Blocking Technology in No-Tillage Wheat Seeding

2012 ◽  
Vol 472-475 ◽  
pp. 55-59
Author(s):  
Xi Rui Zhang ◽  
Lu Guo ◽  
Hong Wen Li ◽  
Jin He ◽  
Lian Rui Zhang
Keyword(s):  
Fuel Consumption ◽  
Field Experiments ◽  
Dry Weight ◽  
Soil Disturbance ◽  
No Tillage ◽  
Double Cropping ◽  
Blocking Device ◽  
Passing Ability ◽  
The Impact ◽  
The Relationship

Due to the large amount of straw in the double cropping area of the northern part in China, this paper developed an anti-blocking device in rotary tillage with three different types: ribbon, grinding and breaking the stubbles. Through analyzing the mechanism of anti-blocking devices, the relationship parameters of the passing ability of equipment, quantity of soil disturbance, fuel consumption and crop growth are identified. Field experiments demonstrate that adopting different anti-blocking devices in the dynamic driving type can produce different seed beds, can influence the quantity of soil disturbance of no-tillage land as well as the roots growth of wheat . By comparing the properties of no-tillage seeding of three anti-blocking devices ,such as quantity of soil disturbance, fuel consumption per unit and the growth of wheat (emergence number, tiller number, secondary root number and dry weight per plant), the impact of grinding type of ribbon is the best, rotary tillage type of ribbon takes second place, type of breaking the stubbles of ribbon rebases.

scholarly journals Evaluation of personal protection afforded by repellent-treated sandals against mosquito bites in south-eastern Tanzania.

2020 ◽  
Author(s):  
Peter Onyango Sangoro ◽  
Tegemeo Gavana ◽  
Marceline Finda ◽  
Winfrida Mponzi ◽  
Emmanuel Hape ◽  
...  
Keyword(s):  
Field Experiments ◽  
Mosquito Species ◽  
Indoor Residual Spraying ◽  
Field Tests ◽  
Malaria Vectors ◽  
Insecticide Treated Nets ◽  
Large Cage ◽  
Full Field ◽  
Targeted Interventions ◽  
The Impact

Abstract Background Outdoor and early evening mosquito biting needs to be addressed if malaria elimination is to be achieved. While indoor-targeted interventions such as insecticide-treated nets and indoor residual spraying remain essential, complementary approaches that tackle persisting outdoor transmission are urgently required to maximize the impact. Major malaria vectors principally bite human hosts around the feet and ankles. Consequently, this study investigated whether sandals treated with efficacious spatial repellents can protect against outdoor biting mosquitoes. Methodology Sandals affixed with hessian bands measuring 48cm 2 treated with 6 ml, 10 ml and 12 ml of transfluthrin were tested in large cage semi-field and full field experiments. Sandals affixed with hessian bands measuring 240cm 2 and treated with 10 ml and 12ml of transfluthrin were also tested semi field experiments. Human landing catches (HLC) were used to assess reduction in biting exposure by comparing proportions of mosquitoes landing on volunteers wearing treated and untreated sandals. Sandals were tested against insectary reared Anopheles arabiensis mosquitoes in semi-field experiments and against wild mosquito species in rural Tanzania. Results In semi-field tests, sandals fitted with hessian bands measuring 48cm 2 and treated with 12 ml, 10ml and 6ml transfluthrin reduced mosquito landings by 45.9%, (95% confidence interval (C.I.) = 28–59%), 61.1% (48%–71%), and 25.9% (9% - 40%) respectively compared to untreated sandals. Sandals fitted with hessian bands measuring 240cm 2 and treated with 12 ml and 10ml transfluthrin reduced mosquito landings by 59% (43 - 71%) and 64% (48 - 74%) respectively. In field experiments, sandals fitted with hessian bands measuring 48cm 2 and treated with 12 ml transfluthrin reduced mosquito landings by 70% (60% - 76%) against Anopheles gambiae s.l and 66.0% (59% - 71%) against all mosquito species combined. Conclusion Transfluthrin-treated sandals conferred significant protection against mosquito bites in semi-field and field settings. Further evaluation is recommended for this tool as a potential complimentary intervention against malaria. This intervention could be particularly useful for protecting against outdoor exposure to mosquito bites. Additional studies are necessary to optimize treatment techniques and substrates, establish safety profiles and determine epidemiological impact in different settings.

scholarly journals Evaluation of personal protection afforded by repellent-treated sandals against mosquito bites in south-eastern Tanzania.

2020 ◽  
Author(s):  
Peter Onyango Sangoro ◽  
Tegemeo Gavana ◽  
Marceline Finda ◽  
Winfrida Mponzi ◽  
Emmanuel Hape ◽  
...  
Keyword(s):  
Field Experiments ◽  
Mosquito Species ◽  
Indoor Residual Spraying ◽  
Field Tests ◽  
Malaria Vectors ◽  
Insecticide Treated Nets ◽  
Large Cage ◽  
Full Field ◽  
Targeted Interventions ◽  
The Impact

Abstract Background Outdoor and early evening mosquito biting needs to be addressed if malaria elimination is to be achieved. While indoor-targeted interventions such as insecticide-treated nets and indoor residual spraying remain essential, complementary approaches that tackle persisting outdoor transmission are urgently required to maximize the impact. Major malaria vectors principally bite human hosts around the feet and ankles. Consequently, this study investigated whether sandals treated with efficacious spatial repellents can protect against outdoor biting mosquitoes. Methodology Sandals affixed with hessian bands measuring 48cm 2 treated with 6 ml, 10 ml and 12 ml of transfluthrin were tested in large cage semi-field and full field experiments. Sandals affixed with hessian bands measuring 240cm 2 and treated with 10 ml and 12ml of transfluthrin were also tested semi field experiments. Human landing catches (HLC) were used to assess reduction in biting exposure by comparing proportions of mosquitoes landing on volunteers wearing treated and untreated sandals. Sandals were tested against insectary reared Anopheles arabiensis mosquitoes in semi-field experiments and against wild mosquito species in rural Tanzania. Results In semi-field tests, sandals fitted with hessian bands measuring 48cm 2 and treated with 12 ml, 10ml and 6ml transfluthrin reduced mosquito landings by 45.9%, (95% confidence interval (C.I.) = 28–59%), 61.1% (48%–71%), and 25.9% (9% - 40%) respectively compared to untreated sandals. Sandals fitted with hessian bands measuring 240cm 2 and treated with 12 ml and 10ml transfluthrin reduced mosquito landings by 59% (43 - 71%) and 64% (48 - 74%) respectively. In field experiments, sandals fitted with hessian bands measuring 48cm 2 and treated with 12 ml transfluthrin reduced mosquito landings by 70% (60% - 76%) against Anopheles gambiae s.l and 66.0% (59% - 71%) against all mosquito species combined. Conclusion Transfluthrin-treated sandals conferred significant protection against mosquito bites in semi-field and field settings. Further evaluation is recommended for this tool as a potential complimentary intervention against malaria. This intervention could be particularly useful for protecting against outdoor exposure to mosquito bites. Additional studies are necessary to optimize treatment techniques and substrates, establish safety profiles and determine epidemiological impact in different settings.

scholarly journals Seedling Blight Development and Control in Spring Wheat Damaged by Fusarium graminearum Group 2

Plant Disease ◽  
1999 ◽  
Vol 83 (11) ◽  
pp. 1013-1018 ◽  
Author(s):  
R. K. Jones
Keyword(s):  
Fusarium Graminearum ◽  
Spring Wheat ◽  
Field Experiments ◽  
Field Tests ◽  
Dry Weight ◽  
Seedling Blight ◽  
Triazole Fungicides ◽  
Surface Sterilization ◽  
Soil Temperatures ◽  
Group 2

Aspects of seedborne infection in Fusarium-damaged and undamaged seed lots of hard red spring wheat were studied. In a 22°C environment, seedling blight developed from plantings of Fusarium-damaged seed that were characterized by both reduction and delay in emergence and postemergence seedling death. After 28 days, stand counts from the Fusarium-damaged seed lot averaged 46%, compared with 98% from the undamaged seed lot. However, the mean dry weight of surviving seedlings from the Fusarium-damaged lot was not statistically different from that of seedlings from the undamaged seed lot. Surface-sterilization reduced recovery of Fusarium graminearum group 2 from the damaged lot by 7% and increased germination by 32%, suggesting that seed are both infected and contaminated with viable propagules of the fungus. In field experiments, seed treatment with maneb- or thiabendazole-containing fungicide combinations significantly reduced seedling blight and improved stands derived from the Fusarium-damaged seed lot. Triazole fungicides, including difenoconazole, fenbuconazole, and tetraconazole, were less effective. Triazole fungicides and carboxin-containing fungicide combinations controlled loose smut in these trials, while maneb seed treatments did not. In four field tests, seedling blight incidence in plantings of Fusarium-damaged seed increased as soil temperatures during emergence increased. The distribution of blighted seedlings was random and not clustered. Seedling blight did not develop in field plantings of the undamaged seed lot.

scholarly journals The Impact of Composted, Municipal Biosolid Amendments to Soil on the Growth and Nutrient Content of Rhododendron × `PJM'

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 789C-789
Author(s):  
Jae H. Han ◽  
George L. Good* ◽  
Harold M. Van Es
Keyword(s):  
Field Experiments ◽  
Block Design ◽  
Dry Weight ◽  
Nutrient Content ◽  
Harvest Date ◽  
Plant Responses ◽  
Severe Drought ◽  
Randomized Block Design ◽  
Compost Application ◽  
The Impact

Field experiments were conducted in 1998 and 1999 to determine the effect of soil-incorporated, composted municipal biosolids on the growth and nutrient content of 30.8 cm-38.5 cm Rhododendron × `PJM' grown as containerized plants. Biosolid compost produced in Endicott, N.Y., was incorporated in May 1998 and 1999 at rates of 0, 9.8 Mg/ha and 19.7 megag/ha to a depth of 23 cm. Each treatment was replicated six times in a randomized block design. Plants were planted 10 June 1998 and 8 June 1999. Plants were harvested 10 June, 19 Aug., and 22 Oct. 1998 and 8 June and 22 Sept.1999 after which they were dried, weighed, and analyzed. During 1998, there was little difference in dry weight or nutrient content in plants harvested at the August harvest date, however, dry weight and most nutrient levels increased with increasing rates of compost application in plants harvested at the October harvest date. In 1999, no statistical differences were noted at the September harvest date in plant dry weight or nutrient content. In 1999, measured soil physical properties (water retention, bulk density, water content, and soil strength) did not differ significantly between treatments. Excellent soil structure and drainage, relatively low rates of compost application and a severe drought may have contributed to the lack of any conclusive results noted in 1999 though some positive plant responses to the treatments were evident in 1998.

scholarly journals Integrated Use of Herbicide and Weed Mulch with Closer Spacing for Weed Management in Dry Direct Seeded Rice

2021 ◽  
Vol 12 (3) ◽  
pp. 222-227
Author(s):  
Sagarika Malik ◽  
◽  
B. Duary ◽  
D. K. Jaiswal ◽  
◽  
...  
Keyword(s):  
Grain Yield ◽  
Water Hyacinth ◽  
Field Experiments ◽  
Oryza Sativa L ◽  
Block Design ◽  
Dry Weight ◽  
Growth And Yield ◽  
Row Spacing ◽  
Direct Seeded ◽  
The Impact

The field experiments were conducted during the wet season of 2015 and 2016 (June to October) at Agricultural Farm, Institute of Agriculture, Visva-Bharati, Sriniketan, India to study the impact of integrated use of weed mulch and herbicide with closer spacing on weed growth and yield of direct seeded dry sown rice (Oryza sativa L.) cultivar MTU 1010. The experiment consisted of twelve treatments involving sole or integrated application of pre-emergence herbicide pendimethalin, mulching with water hyacinth and Indigofera weed and closer row spacing of 20 cm. The experiment was laid out in randomized block design with three replications. The experimental field was infested with 14 weeds out of which the predominant species were Cynodon dactylon, Echinochloa colona, Cyperus iria, Ludwigia parviflora, Hydrolea zeylanica, Spilanthes acmella, Alternanthera sessilis, Commelina benghalensis and Cyanotis axillaris. Integration of pendimethalin at 0.75 kg ha-1 and mulching with water hyacinth and closer spacing reduced weed dry weight by 75.92% over the weedy check. Integration of mulching with water hyacinth and closer spacing increased grain yield by 37.27 and 41.12% over sole application of pendimethalin and water hyacinth mulch, respectively. Weed competition resulted in 57% reduction in grain yield of rice. Hand weeding twice (25 and 45 DAS) had a significant effect on the reduction of weed density and dry weight and increasing grain yield of rice which was followed by application of pendimethalin 0.75 kg ha-1 along with mulching with water hyacinth at a closer row spacing of 20 cm.

INFLUENCE OF THE DIFFERENT SOIL PREPARATION METHODS ON THE PEA YIELD

2018 ◽  
pp. 16-20
Author(s):  
А. М. Grebennikov ◽  
А. S. Frid ◽  
V. P. Belobrov ◽  
V. А. Isaev ◽  
V. М. Garmashоv ◽  
...  
Keyword(s):  
Field Experiments ◽  
Morphological Properties ◽  
Mineral Fertilizers ◽  
First Year ◽  
Zero Tillage ◽  
Preparation Methods ◽  
Soil Preparation ◽  
Multifactor Analysis ◽  
The Impact ◽  
Central Chernozem

The article assesses the relationships between the morphological properties of agrochernozems and yield of peas on the plots, experience with different methods of basic treatment (moldboard plowing at the depth of 20 - 22, 25 - 27 and 14 - 16 cm, moldboard plowing to a depth of 14 - 16 cm, combined midwater moldboard, mid-water subsurface, surface to a depth of 6 - 8 cm and zero tillage) is inherent in V.V. Dokuchaev Research Institute of Agriculture of the Central Black Earth strip, in the fall of 2014. The research was conducted in 2015 - 2016, with the application of mineral fertilizers (N60Р60К60) and unfertilized background. The highest pea yields in the fertilized as the background, and without the use of fertilizers was observed in dumping plowing and especially in the variant with deep moldboard plowing, which creates in comparison with other ways of handling the best conditions for the growth and development of peas. The lowest yield of pea was obtained with zero processing. Apparently legalistic migrational-mizelial agrochernozems the Central Chernozem zone of minimum tillage in the cultivation of peas are not effective, what is evident already in the first year after the laying of experience with different basic treatments. As shown by the results of applying multifactor analysis of variance studied the mapping properties of the soil can have the same significant impact on the yield of agricultural crops, as options for the field experiments aimed at assessing the impact of various treatments on yield.

The yield of perennial grass stands on drained organic soils of Steppe

2016 ◽  
Vol 1 (90) ◽  
pp. 92-97
Author(s):  
I.T. Slusar ◽  
V.A. Serbenyuk ◽  
A.N. Gera ◽  
A.P. Solyanik ◽  
A.A. Tarasenko
Keyword(s):  
Zinc Sulphate ◽  
Foliar Application ◽  
Perennial Grass ◽  
Mineral Fertilizer ◽  
Dry Weight ◽  
Research Area ◽  
Organic Soils ◽  
Growth Promoters ◽  
Cobalt Sulfate ◽  
The Impact

Research on the impact of the introduction of micro fertilizers and growth promoters on a background of mineral fertilizer and without N90R45К120 spent on old peat in shallow carbonate floodplain r.Supiy, Yahotyn Kyiv region. Power peat horizon about 60-70 cm, 7,4-7,6 pH of the aqueous extract, stupas schedule 56-60%, density 0,49-0,52 assembly soil, total nitrogen content (%) - 1.9; gross forms of phosphorus - 0,4, potassium 0.2, 20% lime. In experiments studying biological rehoplant, radustym, Biolan, emistim, Jets, humisol, plantafol, radyfarm and micronutrients: copper, boric acid, manganese sulphate, zinc sulphate, potassium humates. Treatment drugs conducted in the spring by spraying mixtures. Space research area of 60 m2, three-time repetition. It is established that the use of growth stimulants and micronutrients in the background N90R45К120 provided the highest yield mixtures of years, against making BIOLan - 9.9 t / ha Radyfarmu - 9.6 t / ha Radostymu 9.3 t / ha dry weight. In areas for making other preparations were intermediate yield growth rates - 0.5 - 2.0 t / ha dry weight. Also good gains herbage yields obtained by making all kinds of micronutrients and growth stimulants in the background without making makrodobryv which was within 5.3 - 6.9 t / ha to control without fertilization - 4.5 t / ha dry weight. In deep peat copper fertilizer (25 kg / ha of copper sulphate or 5 kg / ha pirytnoho cinders) in all zones should be making every 3-4 years, and zinc, cobalt and molybdenum advisable to make time for the growing season, spring, by foliar application in such numbers: ammonium molibdenovokyslyy - 0.3 kg / ha; cobalt sulfate - 3 kg / ha zinc sulphate 0.5 kg / ha or placers these salts should be mixed with major fertilizer.

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