scholarly journals RESEARCH ON DESIGN AND EXPERIMENT OF MULTIFUNCTIONAL VEGETABLE FIELD MACHINE

2021 ◽  
pp. 434-442
Author(s):  
Shuo Zhang ◽  
Qingyu Chen ◽  
Jinyi Liu ◽  
Y Chen ◽  
Jun Chen ◽  
...  

Vegetable industry occupies a significant position in the world agricultural production, China has been the largest vegetable producing country in the world. However, the mechanization of vegetable production is still in the initial stage. There are many problems such as complex environment, non-uniform agronomy, various kinds of agricultural machinery etc. In order to meet the varied requirements of vegetable field work, in this paper, a new type of high-efficiency vegetable field operation power equipment was developed by adopting the idea of "frame-type", and the key components are developed. They include ground gap adjusting mechanism, wheel spacing adjusting mechanism, inter-axle hitch mechanism, the rear hitch mechanism and frame. The vibration modal analysis and stiffness analysis of the frame are carried out by ANSYS, which proves that the frame design is reasonable and meets the use requirements. Finally, a prototype was made and field experiments were carried out. The results showed that the maximum running speed of the multifunctional vegetable field machine was 16 km/h, the maximum operating speed was 8 km/h, the maximum gradient was 20, and the adjustable range of ground clearance was 400~800 mm. The adjustable range of wheel spacing was 1600-2000 mm.

Author(s):  
Yu.I. Agirbov ◽  
◽  
R.R. Mukhametzyanov ◽  
E.V. Britik ◽  
◽  
...  

In 1961-2018 in the world as a whole, the gross harvest of potatoes increased from 290.6 million tons to 368.2 million tons, that is, 1.36 times. Over the same period, the production of vegetables and food melons increased from 197.7 million tons to 1,088.8 million tons (5.51 times), and fruits and berries from 199.9 million tons to 867.8 million tons (4.34 times). In a number of states in 1992-2018 the corresponding increase significantly exceeded the average values for the world as a whole, as a result of which their place in the global ranking increased, and the positions of some traditional producers of potatoes and fruits and vegetables decreased. For example, in terms of gross harvest of potatoes in 1992, Russia was in first place, and Poland was in third, while in 2018 they were in 4th and 9th positions, respectively. In terms of vegetable production, Italy and Japan were displaced from 4th and 5th places, which were taken by Turkey and Nigeria. In terms of gross harvests of fruits and berries, Turkey occupied the fifth position in total world production by 2018, although in 1992 it belonged to Italy. Quantitative and qualitative changes inevitably have a significant impact on both the volume of the world market and the parameters of international trade in potatoes, vegetables and melons, fruits and berries. Processes in foreign economic liberalization and economic integration contributed to an increase in the specialization and concentration of production of relevant plants in countries with more favorable natural and climatic conditions, as well as a gradual increase in demand for potatoes, vegetables and melons, fruits and berries from a number of states, including those that used to meet the needs of their population in large volumes at the expense of their own producers. The Russian Federation is one of the significant players in the world potato and fruit and vegetable market. Despite the increase in gross fruit and vegetable production in recent years, Russia’s positions in the global rating dropped from 7th to 10th place in vegetables and melons, from 20th to 31st place in fruits and berries. As for potatoes, there was a decrease in the volume of its production, as a result, Russia dropped from 1st place in 1992 to 4th place in 2018.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 545d-545
Author(s):  
D.I. Leskovar ◽  
J.C. Ward ◽  
R.W. Sprague ◽  
A. Meiri

Water pumping restrictions of high-quality irrigation water from underground aquifers is affecting vegetable production in Southwest Texas. There is a need to develop efficient deficit-irrigation strategies to minimize irrigation inputs and maintain crop profitability. Our objective was to determine how growth, yield, and quality of cantaloupe (Cucumis melo L. cv. `Caravelle') are affected by irrigation systems with varying input levels, including drip depth position and polyethylene mulch. Stand establishment systems used were containerized transplants and direct seeding. Field experiments were conducted on a Uvalde silty clay loam soil. Marketable yields increased in the order of pre-irrigation followed by: dry-land conditions, furrow/no-mulch, furrow/mulch, drip-surface (0 cm depth)/mulch, drip-subsurface (10-cm depth)/mulch, and drip-subsurface (30 cm depth)/mulch. Pooled across all drip depth treatments, plants on drip had higher water use efficiency than plants on furrow/no-mulch or furrow/mulch systems. Transplants with drip-surface produced 75% higher total and fruit size No. 9 yields than drip-subsurface (10- or 30-cm depth) during the first harvest, but total yields were unaffected by drip tape position. About similar trends were measured in a subsequent study except for a significant irrigation system (stand establishment interaction for yield. Total yields were highest for transplants on drip-subsurface (10-cm depth) and direct seeded plants on drip-subsurface (10 and 30 cm depth) with mulch.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Tianhao Wu ◽  
Zhenzhen Qin ◽  
Yanbo Wang ◽  
Yongzhen Wu ◽  
Wei Chen ◽  
...  

AbstractPerovskite solar cells (PSCs) emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world. Both the efficiency and stability of PSCs have increased steadily in recent years, and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step. This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency, stability, perovskite-based tandem devices, and lead-free PSCs. Moreover, a brief discussion on the development of PSC modules and its challenges toward practical application is provided.


2021 ◽  
pp. 014459872098020
Author(s):  
Ruizhi Hu ◽  
Shanfa Tang ◽  
Musa Mpelwa ◽  
Zhaowen Jiang ◽  
Shuyun Feng

Although new energy has been widely used in our lives, oil is still one of the main energy sources in the world. After the application of traditional oil recovery methods, there are still a large number of oil layers that have not been exploited, and there is still a need to further increase oil recovery to meet the urgent need for oil in the world economic development. Chemically enhanced oil recovery (CEOR) is considered to be a kind of effective enhanced oil recovery technology, which has achieved good results in the field, but these technologies cannot simultaneously effectively improve oil sweep efficiency, oil washing efficiency, good injectability, and reservoir environment adaptability. Viscoelastic surfactants (VES) have unique micelle structure and aggregation behavior, high efficiency in reducing the interfacial tension of oil and water, and the most important and unique viscoelasticity, etc., which has attracted the attention of academics and field experts and introduced into the technical research of enhanced oil recovery. In this paper, the mechanism and research status of viscoelastic surfactant flooding are discussed in detail and focused, and the results of viscoelastic surfactant flooding experiments under different conditions are summarized. Finally, the problems to be solved by viscoelastic surfactant flooding are introduced, and the countermeasures to solve the problems are put forward. This overview presents extensive information about viscoelastic surfactant flooding used for EOR, and is intended to help researchers and professionals in this field understand the current situation.


2021 ◽  
Vol 13 (2) ◽  
pp. 642
Author(s):  
Shuangxi Zhou ◽  
Zhenzhen Guo ◽  
Yang Ding ◽  
Jingliang Dong ◽  
Jianming Le ◽  
...  

Buildings consume many resources and generate greenhouse gases during construction. One of the main sources of greenhouse gases is carbon emission associated with buildings. This research is based on the computing rule of carbon emission at the materialization stage. By taking the features of green construction into consideration, quantitative analysis on construction carbon emission was undertaken via Life Cycle Assessment (LCA). Making use of Vensim (a system dynamics software package), we analyzed the amount of carbon emission at the materialization stage and determined the major subsystems affecting the carbon emission, then took into comprehensive consideration the differences of each subsystem’s carbon emission under different construction technologies. Under the mechanism of carbon trade at the materialization stage, the total price of carbon trades remains unchanged, while the trading price of each subsystem is adjusted. Under these conditions, a coefficient for step-wise increases in carbon price was proposed. By establishing such a system of gradient prices, construction companies are encouraged to adopt high-efficiency emission reduction technologies. Meanwhile, the system also provides a reference for the formulation of price-based policies about buildings’ carbon trading, and accelerates the process of energy conservation and emission reduction in China and the world at large.


2003 ◽  
Vol 49 (5) ◽  
pp. 465-483 ◽  
Author(s):  
Katalin Debreczeni ◽  
Martin Körschens

1956 ◽  
Vol 15 (4) ◽  
pp. 24-29
Author(s):  
John Gillin

Are there any methods whereby we may understand the cultures of modern nation-societies both as to their detailed components and as to their total configurational characteristics? Anthropologists receive such queries because modern ethnological field work and other anthropological methods have been able to produce reliable descriptive analyses of so-called primitive tribes and small communities that are both comprehensive and detailed. And, on the basis of such data collected in a wide variety of cultures around the world, science has acquired not only a rich store of knowledge concerning the substantive varieties of human social behavior, but also a fairly elaborated theoretical apparatus regarding culture in general. With such knowledge and theory it is possible to explain and even to predict many human behaviors and attitudes that were formerly beyond the reach of science.


2017 ◽  
Vol 24 (6) ◽  
pp. 371-380
Author(s):  
Anandam Kavoori

This autoethnographic essay is focused on methodological space of “problematization”—the wrenching intellectual and emotional process (and lived experience) that a scholar goes through before settling into a long-term writing project—in this case travel to different parts of the world, in an attempt to explore the idea and experience of “Peace” in each of those places. Weaving through elements of family memoir, Georgia history, eco-criticism, and Peace Studies (across different sub fields), the essay illuminates the personal and liminal space of methodological engagement before field work.


Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3169
Author(s):  
Roberto Gaudio

The main focus of this Special Issue of Water is the state-of-the-art and recent research on turbulence and flow–sediment interactions in open-channel flows. Our knowledge of river hydraulics is becoming deeper and deeper, thanks to both laboratory/field experiments related to the characteristics of turbulence and their link to the erosion, transport, deposition, and local scouring phenomena. Collaboration among engineers, physicists, and other experts is increasing and furnishing new inter/multidisciplinary perspectives to the research in river hydraulics and fluid mechanics. At the same time, the development of both sophisticated laboratory instrumentation and computing skills is giving rise to excellent experimental–numerical comparative studies. Thus, this Special Issue, with ten papers by researchers from many institutions around the world, aims at offering a modern panoramic view on all the above aspects to the vast audience of river researchers.


Author(s):  
D. R. M. Samudraiah ◽  
M. Saxena ◽  
S. Paul ◽  
P. Narayanababu ◽  
S. Kuriakose ◽  
...  

The world is increasingly depending on remotely sensed data. The data is regularly used for monitoring the earth resources and also for solving problems of the world like disasters, climate degradation, etc. Remotely sensed data has changed our perspective of understanding of other planets. With innovative approaches in data utilization, the demands of remote sensing data are ever increasing. More and more research and developments are taken up for data utilization. The satellite resources are scarce and each launch costs heavily. Each launch is also associated with large effort for developing the hardware prior to launch. It is also associated with large number of software elements and mathematical algorithms post-launch. The proliferation of low-earth and geostationary satellites has led to increased scarcity in the available orbital slots for the newer satellites. Indian Space Research Organization has always tried to maximize the utility of satellites. Multiple sensors are flown on each satellite. In each of the satellites, sensors are designed to cater to various spectral bands/frequencies, spatial and temporal resolutions. Bhaskara-1, the first experimental satellite started with 2 bands in electro-optical spectrum and 3 bands in microwave spectrum. The recent Resourcesat-2 incorporates very efficient image acquisition approach with multi-resolution (3 types of spatial resolution) multi-band (4 spectral bands) electro-optical sensors (LISS-4, LISS-3* and AWiFS). The system has been designed to provide data globally with various data reception stations and onboard data storage capabilities. Oceansat-2 satellite has unique sensor combination with 8 band electro-optical high sensitive ocean colour monitor (catering to ocean and land) along with Ku band scatterometer to acquire information on ocean winds. INSAT- 3D launched recently provides high resolution 6 band image data in visible, short-wave, mid-wave and long-wave infrared spectrum. It also has 19 band sounder for providing vertical profile of water vapour, temperature, etc. The same system has data relay transponders for acquiring data from weather stations. The payload configurations have gone through significant changes over the years to increase data rate per kilogram of payload. Future Indian remote sensing systems are planned with very high efficient ways of image acquisition. <br><br> This paper analyses the strides taken by ISRO (Indian Space research Organisation) in achieving high efficiency in remote sensing image data acquisition. Parameters related to efficiency of image data acquisition are defined and a methodology is worked out to compute the same. Some of the Indian payloads are analysed with respect to some of the system/ subsystem parameters that decide the configuration of payload. Based on the analysis, possible configuration approaches that can provide high efficiency are identified. A case study is carried out with improved configuration and the results of efficiency improvements are reported. This methodology may be used for assessing other electro-optical payloads or missions and can be extended to other types of payloads and missions.


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