A RAPID TACTICAL MINE-PLANTING SYSTEM: HOW FORCE LEVEL AFFECTS LEVER-THROWING TIME.

1966 ◽  
Author(s):  
GEORGE G. GENTRY ◽  
R. BRADLEY RANDALL
Keyword(s):  
Force Level ◽  
Planting System

An Experimental Investigation of the Dynamics of a Loosely Supported Tube Array

2017 ◽  
Author(s):  
Amro Elhelaly ◽  
Marwan Hassan ◽  
Atef Mohany ◽  
Soha Moussa
Keyword(s):  
Experimental Investigation ◽  
Impact Force ◽  
Cross Flow ◽  
Open Loop ◽  
Diameter Ratio ◽  
Force Level ◽  
Steam Generators ◽  
Flow Induced Vibration ◽  
System Integrity ◽  
Tube Bundles

The integrity of tube bundles is very important especially when dealing with high-risk applications such as nuclear steam generators. A major issue to system integrity is the flow-induced vibration (FIV). FIV is manifested through several mechanisms including the most severe mechanism; fluidelastic instability (FEI). Tube vibration can be constrained by using tube supports. However, clearances between the tube and their support are required to allow for thermal expansion and for other manufacturing considerations. The clearance between tubes may allow frequent impact and friction between tube and support. This in turn may cause fatigue and wear at support and potential for catastrophic tube failure. This study aims to investigate the dynamics of loosely supported tube array subjected to cross-flow. The work is performed experimentally in an open-loop wind tunnel to address this issue. A loosely-supported single flexible tube in both triangle and square arrays subjected to cross-flow with a pitch-to-diameter ratio of 1.5 and 1.733, respectively were considered. The effect of the flow approach angle, as well as the support clearance on the tube response, are investigated. In addition, the parameters that affect tube wear such as impact force level are presented.

scholarly journals Camouflaging of seeds treated with pesticides mitigates the mortality of wild birds in wheat and rice crops

2010 ◽  
Vol 67 (2) ◽  
pp. 176-182 ◽  
Author(s):  
Alexandre de Almeida ◽  
Hilton Thadeu Zarate do Couto ◽  
Álvaro Fernando de Almeida
Keyword(s):  
Rhodamine B ◽  
Apparent Movement ◽  
Sao Paulo ◽  
Wild Birds ◽  
São Paulo ◽  
Seed Treatments ◽  
Legal Requirement ◽  
Bird Mortality ◽  
Planting System

Seeds used to plant wheat, corn and rice crops in Brazil are treated with the insecticide carbofuran associated with the dye rhodamine B, attracting granivorous birds and causing mortality during sowing. The objective of this study was to evaluate if using camouflaged seeds can minimize mortality caused by the ingestion of seeds with carbofuran. Alternatives for reducing mortality, such as using carbofuran without rhodamine B or replacing carbofuran by carbosulfan, were compared. Three experiments were carried out in regions of known bird mortality in the states of Paraná and São Paulo, Brazil, using conventional sowing over plowed soil in the traditional planting system, 15,896 kg of seeds in 111.46 ha. Bird carcasses were collected and dissected to unveil which poisoned seed treatments had caused birds' deaths. The mortality mounted to 296 birds of 11 species. Eared doves were the most numerous casualties (263). There was significant correlation between mortality and number of consumed seeds. The consumption of camouflaged seeds was lower than that of commercial seeds treated with rhodamine B. The mortality caused by seeds with both rhodamine B and carbofuran was higher than mortality caused by seeds camouflaged only with carbofuran. The replacement of carbofuran with carbosulfan also seemingly reduced mortality, but carbosulfan mortality might have been underestimated as a result of the apparent movement of affected birds after exposure. Seeds treated with carbofuran and rhodamine B and without any dye, were attractive. Because legal requirement for seeds treated with pesticides to be differentiated by dying, the substitution of rhodamine B by camouflaging must be encouraged.

IDROPO, A Hydroponic Planting System to Teach Gardening Through Play

2018 ◽  
Author(s):  
Federica Carrozzo ◽  
Ruben Faccini ◽  
Angelo Falci ◽  
Beatrice Redaelli ◽  
Mirko Gelsomini ◽  
...  
Keyword(s):  
Planting System

Neuronal mechanisms underlying physiological tremor

1978 ◽  
Vol 41 (3) ◽  
pp. 557-571 ◽  
Author(s):  
J. H. Allum ◽  
V. Dietz ◽  
H. J. Freund
Keyword(s):  
Power Spectrum ◽  
Pathological Condition ◽  
Power Spectra ◽  
Motor Units ◽  
Physiological Tremor ◽  
Force Level ◽  
Force Output ◽  
Experimental Conditions ◽  
Single Motor Unit ◽  
Total Fusion

1. Tremor force was recorded during stationary isometric contractions of intrinsic hand muscles of normal subjects. Subjects maintained a steady force level between their thumb and forefinger for 30 s. The force level varied from weak (0.2 kg) to strong contractions (7 kg). These experimental conditions were the same as those in two preceding studies, where single motor-unit activity (14) and the correlation between the discharges of two simultaneously recorded motor units and physiological tremor (11) have been investigated. 2. Two alterations of the power spectra were observed at successively stronger contractions: increase of tremor amplitude and changes in the shape of the power spectrum. At all force levels, the power spectra of tremor force show the well-known decay of tremor amplitude from the lower to the higher frequencies with a local peak at 6--10 Hz. This peak does not show a significant change with respect to frequency when the force level is varied. It is shifted toward lower frequencies in a pathological condition (Parkinsonism) where the recruitment firing rates of the motor units are significantly lower than in the normal. 3. Higher frequencies (greater than 20 Hz) are barely present in the power spectrum during the very weak contractions. They become significant as the contractions become stronger. 4. The steep decay of the power spectrum toward higher frequencies has a similar slope (--43 dB/decade) as the reduction in amplitude of the unfused part of the muscle contractions with increasing stimulus rates (--38 dB/decade). The cutoff of the power spectrum above 25 Hz parallels the achievement of total fusion of muscle twitches above this rate. 5. The results are consistent with the hypothesis that the power spectrum over the range of 6--25 Hz is mainly caused by the unfused parts of the twitch contractions of motor units firing between recruitment (6--8/s) and total fusion of the twitches (25--30/s). The decline of the power spectrum toward higher frequencies can be explained by mechanical damping, which results from increasing fusion of the twitch contractions. The low-frequency part of the power spectrum is assumed to be the result of the slow force deviations produced by changes in the net output of the motoneuron pool. 6. These assumptions were supported by additional animal experiments where the number and rate of force-producing elements could be controlled. Bundles of ventral root filaments innervating cat soleus and gastrocnemius muscles were stimulated synchronously and asynchronously at a number of different rates. The force output of the strain gauge was recorded, filtered, and analyzed in the same way as the human force records. 7. Stimualtion of one nerve bundle at one fixed frequency led to a sharp peak in the power spectrum at that frequency plus peaks of decreasing height representing the harmonics of the stimulation frequency. The height of the peaks decreased at --37 dB/decade. 8...

scholarly journals ONION GENOTYPE SKILLS IN DIFFERENT PLANTING SYSTEMS

2019 ◽  
Vol 17 (2) ◽  
pp. 35
Author(s):  
Gabriel Mascarenhas Maciel ◽  
Guilherme Repeza Marquez ◽  
Ariel Santivañez Aguilar ◽  
Igor Forigo Beloti ◽  
Igor Matheus Alves ◽  
...  
Keyword(s):  
Rio Grande ◽  
The State ◽  
No Tillage ◽  
Seedling Production ◽  
Rio Grande Do Sul ◽  
No Till ◽  
Northwestern Region ◽  
Agronomic Potential ◽  
Planting System

Currently, planting onion through seedling production is predominant in the state of Rio Grande do Sul. Thus, the present work aimed to evaluate the agronomic potential of new onion genotypes as a function of the planting system for this region. Eleven genotypes were evaluated, as follows: “commercial genotypes” Bola Precoce, Mulata, Sprint, Suprema and “pre-commercial genotypes” TE 201, TE 209, TE 216, TE 230, TE 242, TE 316 and TE 329, submitted to four planting systems: seedling production, seedling production with leaf pruning before transplanting, no-tillage manually planted at the definitive site and seedling production in trays. Treatments were arranged in an 11 x 4 factorial scheme (eleven genotypes and four planting systems). Although little practiced, the no-till system for onion cultivation for the northwestern region of Rio Grande do Sul can potentially be explored. Genotypes that best adapted to this system were: Bola Precoce, Suprema, Sprint, Mulata and TE 201. Comparatively, “commercial” genotypes showed an increase of 10.81 t ha-1 in relation to “pre-commercial” genotypes in the no-till system, proving the efficiency of this system.

scholarly journals PENGARUH JARAK TANAM PADA SISTEM TANAM JAJAR LEGOWO TERHADAP PERTUMBUHAN, PRODUKTIVITAS DAN PENDAPATAN PETANI PADI SAWAH DI KABUPATEN SRAGEN JAWA TENGAH

2018 ◽  
Vol 13 (2) ◽  
pp. 188
Author(s):  
Tota Suhendrata
Keyword(s):  
Data Analysis ◽  
Paddy Rice ◽  
Plant Spacing ◽  
Rice Seedlings ◽  
Financial Feasibility ◽  
Input And Output ◽  
Planting Distance ◽  
Paired T Test ◽  
Planting System ◽  
Padi Rice

<p>Abstract : One of the efforts to increase the productivity of paddy rice by setting the<br />right spacing. At this time,  developing technology engine planting of rice seedlings<br />(rice transplanter) which introducing plant spacing ranging from narrow spacing to<br />large plant spacing both on legowo row planting system and tile planting system. With<br />regard to the introduction of these technologies, further research is needed in the<br />effect of plant spacing on growth, productivity (grain yield) and income of paddy rice<br />farmers. The assessment was carried out on the wetland of farmer group of Rukun<br />Tani Sulur  Blimbing Village of Sragen Regency on July – October 2014. The<br />assessment consisted of 3 planting distance treatment of legowo row 2: 1 planting<br />system, ie 20 x 10 x 40 cm, 20 x 13 x 15 cm and 20 x 15 x 40 cm, each treatment<br />repeated 7 times. The area of each treatment is about 0.33 ha. The assessment<br />involves 7 farmers, each farmer carrying out 3 treatment. The seedlings using legowo<br />2:1planting system of rice transplanter. This rice transplanter has 3 combination of<br />plant distance, that is 20 x 10 x 40 cm, 20 x 13 x 15 cm and 20 x 15 x 40 cm. The data<br />collected includes the number of productive tillers, productivity, input and output of<br />farming. Data analysis to compare between 3 treatment by using paired t test. While<br />the analysis of financial feasibility of paddy farming technology using partial budget<br />analysis. The results of this assessment showed that a legowo row 2:1 planting system<br />with plant distance 20 x 15 x 40 cm resulted in highest productive tillers, productivity<br />and income compared to the legowo 2:1 with a narrower plant distance 20 x 10 x 40<br />cm and 20 x 13 x 40 cm.</p><p> </p><p>Abstrak: Salah satu upaya untuk meningkatkan produktivitas padi sawah melalui<br />pengaturan jarak tanam yang tepat. Pada saat ini, berkembang teknologi mesin tanam<br />bibit padi (rice transplanter) yang mengintroduksikan jarak tanam mulai dari jarak<br />tanam sempit sampai dengan jarak tanam lebar baik pada sistem tanam jajar legowo<br />maupun sistem tanam tegel. Berkenaan dengan introduksi teknologi tersebut perlu<br />dilakukan penelitian lebih dalam pengaruh jarak tanam terhadap pertumbuhan,<br />produktivitas (hasil gabah) dan pendapatan petani padi sawah. Pengkajian<br />dilaksanakan pada lahan sawah kelompok tani Rukun Tani Sulur  Desa Blimbing Kec.<br />Sambirejo Kab. Sragen Jawa Tengah pada MT-3 2014. Pengkajian terdiri dari 3<br />perlakuan jarak tanam pada sistem tanam jajar legowo 2:1, yaitu  20 x 10 x 40 cm, 20<br />x 13 x 15 cm dan 20 x 15 x 40 cm dengan 7 kali ulangan. Luas masing-masing<br />perlakuan sekitar 0,33 ha.  Pengkajian melibatkan 7 orang petani, setiap petani<br />melaksanakan 3 perlakuan. Tanam bibit padi menggunakan mesin tanam bibit padi  4<br />baris sistem tanam jajar legowo 2:1. Mesin tanam ini mempunyai 3 kombinasi  jarak<br />tanam, yaitu  20 x 10 x 40 cm, 20 x 13 x 15 cm dan 20 x 15 x 40 cm.  Data yang<br />dikumpulkan meliputi jumlah anakan produktif, produktivitas, input dan output<br />usahatani.  Analisis data untuk membandingkan antara 3 perlakuan jarak tanam dilakukan uji t berpasangan dengan menggunakan software SPSS Statistics 17.0. <br />Sedangkan analisis kelayakan finansial teknologi usahatani padi sawah menggunakan<br />analisis anggaran parsial.  Hasil pengkajian menunjukkan bahwa sistem tanam jajar<br />legowo 2:1 dengan jarak tanam lebar (20 x 15 x 40 cm) menghasilkan jumlah anakan<br />produktif,  produktivitas dan pendapatan yang lebih tinggi dibandingkan sistem tanam<br />jajar legowo 2:1 dengan jarak tanam yang lebih sempit (20 x 10 x 40 cm dan 20 x 13 x<br />40 cm).</p>

scholarly journals EFISIENSI EKONOMI SISTEM TANAM LEGOWO PADI SAWAH STUDI KASUS DI KECAMATAN TOMOHON BARAT KOTA TOMOHON

2019 ◽  
Vol 15 (3) ◽  
pp. 553
Author(s):  
Djuru Masrib Pandensolang ◽  
Vicky Ventje Johan Panelewen ◽  
Wenny ., Tilaar
Keyword(s):  
Economic Efficiency ◽  
Rice Production ◽  
Rice Fields ◽  
Survey Method ◽  
Land Area ◽  
Factors Affecting ◽  
North Sulawesi ◽  
Production Factors ◽  
Planting System ◽  
System Analyzing

This study aims to analyze how much profit is gained by applying the Legowo row planting system, analyzing the factors of production that affect rice production by applying the Legowo row planting system, analyzing whetherthe use of production factors allocated by farmers to the Legowo planting system economically already efficient. The study was conducted from January to April 2019 in Tomohon Barat Subdistrict, Tomohon City, North Sulawesi Province. The research location was chosen purposively with the consideration that West Tomohon Subdistrict was the center of rice production in Tomohon City with a total area of 447.40 ha of rice fields ( 52% of the total area of rice fields in Tomohon City). The method used in this study is a survey method in the Kelurahan that has paddy fields in the West Tomohon District with interview techniques to respondent farmers. Determination of the sample is done by quota sampling method as many as 50 people taken from 7 (seven) villages in the District of West Tomohon by considering the area of land and the purpose of farming (commercial farm). The variables to be examined in this study are age, education, business experience, group membership, land area, seeds, fertilizer (Urea, SP36 and NPK), labor (HKSP), production, and price. The results showed that the benefits of lowland rice farming with the application of the legowo planting system, farmers in Tomohon Barat Subdistrict, Tomohon City were not yet maximum and had not yet reached economic efficiency, production factors affecting rice production were land area, seeds, fertilizer (Urea, SP 36 and NPK Phonska) and labor, the use of production factors of land area, fertilizers(Urea, SP 36 and NPK Phonska) have not reached economic efficiency, the use of seed production factors and labor is inefficient.*eprm*

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