scholarly journals DESIGN AND PARAMETER OPTIMIZATION OF WATER-RETAINING MOULDING DEVICE FOR STRAW AND COW DUNG MIXED MATERIALS

2021 ◽  
pp. 195-204
Author(s):  
Tiejun Wang ◽  
Ruili Wang ◽  
Jin Yu ◽  
Yuanjuan Gong ◽  
Tieliang Wang

A hydraulic horizontal water-retaining moulding device for mixed materials was designed and optimized. The effect of compression process parameters of the mixture of straw and cow dung on the effect of water retention moulding was analysed through experiment. The suitable value range and critical value of process parameters were obtained. The main power and structural parameters of the hydraulic system in the mixture compression unit were designed and calculated. Appropriate hydraulic and control components were selected. A test prototype of the hydraulic horizontal mixed material compressor machine was manufactured. Through the method of combination experiment and response surface optimization, the optimal combination of working parameters of the hydraulic horizontal water-retaining moulding device was obtained and verified. The dimensional stability of small-scale compost blocks made by the compressor could reach 84.71% under the condition of 250 mm/min for the compression speed, 55 kg for the feed amount and 200 s for the holding time.

2020 ◽  
pp. 140-148
Author(s):  
Md. Kumail Naqvi ◽  
Mrinal Anthwal ◽  
Ravindra Kumar

Biogas is the product of anaerobic vitiation of biodegradable matter. This paper focuses on the need of alternative and green sources of energy at a household level and how biogas produced from the everyday organic waste has the potential and possibility to replace LPG cylinders at houses, shops etc. and empower us to step towards an eco-friendly future. The purpose this small-scale experiment has been to find the perfect input matter that is easy to acquire and which produces the maximum amount of gas from minimum input and within small period of waste retention. Four different types of input waste material containing different quantities of cow dung and kitchen food waste were studied through individual experimental setups. Waste was mixed and kept at room temperature and the pH and total solid concentration of the samples were recorded on regular intervals. From the experiment it was found that the optimum yield of biogas at a small scale, based on the parameters such as retention period, pH and total solid con-centration can be obtained by the use of food waste form households and kitchens. The exact composition has been discussed in this paper. The energy generated by the small-scale generator has also been compared to that of an LPG cylinder and an LPG replacement model has also been presented.


2007 ◽  
Vol 158 (8) ◽  
pp. 235-242 ◽  
Author(s):  
Hans Rudolf Heinimann

The term «precision forestry» was first introduced and discussed at a conference in 2001. The aims of this paper are to explore the scientific roots of the precision concept, define «precision forestry», and sketch the challenges that the implementation of this new concept may present to practitioners, educators, and researchers. The term «precision» does not mean accuracy on a small scale, but instead refers to the concurrent coordination and control of processes at spatial scales between 1 m and 100 km. Precision strives for an automatic control of processes. Precision land use differs from precision engineering by the requirements of gathering,storing and managing spatio-temporal variability of site and vegetation parameters. Practitioners will be facing the challenge of designing holistic, standardized business processes that are valid for whole networks of firms,and that follow available standards (e.g., SCOR, WoodX). There is a need to educate and train forestry professionals in the areas of business process re-engineering, computer supported management of business transactions,methods of remote sensing, sensor technology and control theory. Researchers will face the challenge of integrating plant physiology, soil physics and production sciences and solving the supply chain coordination problem (SCCP).


Author(s):  
Anthony Ryan Hatch ◽  
Julia T. Gordon ◽  
Sonya R. Sternlieb

The new artificial pancreas system includes a body-attached blood glucose sensor that tracks glucose levels, a worn insulin infusion pump that communicates with the sensor, and features new software that integrates the two systems. The artificial pancreas is purportedly revolutionary because of its closed-loop design, which means that the machine can give insulin without direct patient intervention. It can read a blood sugar and administer insulin based on an algorithm. But, the hardware for the corporate artificial pancreas is expensive and its software code is closed-access. Yet, well-educated, tech-savvy diabetics have been fashioning their own fully automated do-it-yourself (DIY) artificial pancreases for years, relying on small-scale manufacturing, open-source software, and inventive repurposing of corporate hardware. In this chapter, we trace the corporate and DIY artificial pancreases as they grapple with issues of design and accessibility in a content where not everyone can become a diabetic cyborg. The corporate artificial pancreas offers the cyborg low levels of agency and no ownership and control over his or her own data; it also requires access to health insurance in order to procure and use the technology. The DIY artificial pancreas offers patients a more robust of agency but also requires high levels of intellectual capital to hack the devices and make the system work safely. We argue that efforts to increase agency, radically democratize biotechnology, and expand information ownership in the DIY movement are characterized by ideologies and social inequalities that also define corporate pathways.


2012 ◽  
Vol 59 (1) ◽  
Author(s):  
Mohd Helmi Sani ◽  
Frank Baganz

At present, there are a number of commercial small scale shaken systems available on the market with instrumented controllable microbioreactors such as Micro–24 Microreactor System (Pall Corporation, Port Washington, NY) and M2P Biolector, (M2P Labs GmbH, Aachen, Germany). The Micro–24 system is basically an orbital shaken 24–well plate that operates at working volume 3 – 7 mL with 24 independent reactors (deep wells, shaken and sparged) running simultaneously. Each reactor is designed as single use reactor that has the ability to continuously monitor and control the pH, DO and temperature. The reactor aeration is supplied by sparging air from gas feeds that can be controlled individually. Furthermore, pH can be controlled by gas sparging using either dilute ammonia or carbon dioxide directly into the culture medium through a membrane at the bottom of each reactor. Chen et al., (2009) evaluated the Micro–24 system for the mammalian cell culture process development and found the Micro–24 system is suitable as scaledown tool for cell culture application. The result showed that intra-well reproducibility, cell growth, metabolites profiles and protein titres were scalable with 2 L bioreactors.


Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 432
Author(s):  
Robin Gutting ◽  
Ralf-Uwe Syrbe ◽  
Karsten Grunewald ◽  
Ulf Mehlig ◽  
Véronique Helfer ◽  
...  

Mangrove forests provide a large variety of ecosystem services (ES) to coastal societies. Using a case study focusing on the Ajuruteua peninsula in Northern Brazil and two ES, food provisioning (ES1) and global climate regulation (ES2), this paper proposes a new framework for quantifying and valuing mangrove ES and allow for their small-scale mapping. We modelled and spatialised the two ES from different perspectives, the demand (ES1) and the supply (ES2) side respectively. This was performed by combining worldwide databases related to the global human population (ES1) or mangrove distribution and canopy height (ES2) with locally derived parameters, such as crab catches (ES1) or species-specific allometric equations based on local estimates of tree structural parameters (ES2). Based on this approach, we could estimate that the area delivers the basic nutrition of about 1400 households, which equals 2.7 million USD, and that the mangrove biomass in the area contains 2.1 million Mg C, amounting to 50.9 million USD, if it were paid as certificates. In addition to those figures, we provide high-resolution maps showing which areas are more valuable for the two respective ES, information that could help inform management strategies in the future.


2021 ◽  
Vol 37 (6) ◽  
pp. 1005-1014
Author(s):  
Guoliang Wei ◽  
Qingsong Zhang ◽  
Biao Wang ◽  
QingXi Liao

HighlightsThe seeder combined the plowing and rotating tillage to overcome the heavy soil and a large amount of straws.The plow could lift and turn the soil and straw before rotary tillage.The optimal working parameters of the seeder were obtained by orthogonal field experiments.Abstract. Rapeseed, one of the most important oil crops in China, is mainly planted in the mid-lower reaches of the Yangtze River. However, limited by the special long-term rice-rapeseed rotation, rotary tillage is applied in most of the planted areas apply instead of plow tillage, leading to a shallow arable layer. On the other hand, maintaining a high-quality seedbed for rapeseed becomes a challenge because a large amount of straw remains buried in the soil. As a solution, a rapeseed direct seeder that combines plow tillage and rotary tillage was designed. The structure of the plowing unit, whose key components were a lifting-turning plow and symmetrical plow, was analyzed based on the forming principle of the plow. Furthermore, a mechanical soil throwing model of the rotary tillage blade was built to determine the structural parameters. Then, the interaction between the rotary tillage unit and the lift-turning plow was analyzed. Finally, the performance and optimal parameters were evaluated by orthogonal field experiments. The seedbed after the operations indicated that the seeder could achieve the function of turning the soil and straw first and then rotating the soil with good passability, mixing the straw and the soil, flattening the surface of the seed bed, and stabilizing the tillage depth. Orthogonal experiments showed that the optimal working parameters of the seeder were as follows: the tillage depth was 180 mm, the equipment forward speed was 2.1 km/h, and the speed of the rotary tillage blade was 250 r/min. Under the optimal parameter combination, the power consumption of the seeder, the thickness of the tillage layer, the crop residue burial efficiency, the soil breakage efficiency, and the flatness of the seed bed surface were 30.48 kW, 231 mm, 90.88%, 93.26%, and 21.15 mm, respectively. The working performance of the seeder could meet the tillage requirements of rapeseed planting. Keywords: Direct seeder, Evaluation, Plow, Plowing-rotating combined tillage, Rapeseed.


Author(s):  
Xiangyu You ◽  
Ping Guo

A novel and simple near-field electrospinning (NFES) method has been developed to fabricate wavy or helical nanofibrous arrays. By alternating the electrostatic signals applied on auxiliary-electrodes (AE), the structural parameters of deposited patterns can be actively controlled. Compared with the traditional electrospinning methods based on the bending and buckling effects or collector movement, the proposed method shows advantages in the controllability, accuracy, and minimal feature size. Forces operating on the electrospinning jet and the time-varying electric field distribution were analyzed to explain the kinematics of the jet. Nanoscale wavy and helical patterns with various structural parameters were fabricated. The effects of experimental process parameters on structural parameters of deposited patterns were analyzed to demonstrate the controllability of our method in fabricating wavy or helical nanofibrous structures. It is envisioned that this method will benefit the applications in the field of photovoltaic devices, sensors, transducers, resonators, and stretchable electronics.


2002 ◽  
Vol 7 (1) ◽  
pp. 27-40 ◽  
Author(s):  
Victor Kardashov ◽  
Shmuel Einav

This paper has considered a novel approach to structural recognition and control of nonlinear reaction-diffusion systems (systems with density dependent diffusion). The main consistence of the approach is interactive variation of the nonlinear diffusion and sources structural parameters that allows to implement a qualitative control and recognition of transitional system conditions (transients). The method of inverse solutions construction allows formulating the new analytic conditions of compactness and periodicity of the transients that is also available for nonintegrated systems. On the other hand, using of energy conservations laws, allows transfer to nonlinear dynamics models that gives the possiblity to apply the modern deterministic chaos theory (particularly the Feigenboum's universal constants and scenario of chaotic transitions).


2009 ◽  
Vol 59 (2) ◽  
pp. 241-247 ◽  
Author(s):  
K. Sekyiamah ◽  
H. Kim

A wastewater treatment plant consists of unit processes designed to achieve specific waste reduction goals. Offensive odors associated with these treatment processes are a constant source of public complaints. The purpose of this study was to statistically determine the process parameters that influence the formation of volatile sulfur compounds (VSCs) in the secondary treatment system. A statistical model was developed to relate the process parameters to the formation of VSCs in this system. The model established that F/M ratio, sludge blanket depth and SSV60 were the dominant process parameters that influenced the formation of VSCs in the secondary sedimentation basin. This model provides a useful tool for plant engineers to predict and control the VSC formation in a secondary activated sludge treatment system.


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