scholarly journals Design and Performance Evaluation of a Stone Crusher

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
I Sulaiman
Keyword(s):  
Material Selection ◽  
Hammer Mill ◽  
Particle Size Reduction ◽  
Uniformity Coefficient ◽  
Standard Design ◽  
Design Requirements ◽  
And Performance ◽  
Major Factors ◽  
Higher Institutions ◽  
Research Centres

Crushers are essential machines in several industries for particle size reduction. They are invaluable in laboratories (higher institutions and research centres), the mining and construction industries. Available crushers are imported and very expensive. This has pushed some workers around Nigeria to crush stones with crude materials and manual labour, to meet the demand of the various sectors while neglecting the hazards involved. A hammer mill has been designed with due considerations to standard design requirements, local content and cost. The power required to crush granite with the desired through put of 400 kg/h was found to be 5.5 kW. Major factors considered for the material selection are the mechanical properties, wear of materials, fabrication requirement and cost. The machine was fabricated using locally available materials. The fabricated stone crusher was tested and the actual capacity was found to be 301 kg/h with a through-put efficiency of 75.4 %. The crushed products were well graded with 1.89 coefficient of gradation and uniformity coefficient of 10.22. The machine was produced at a cost of two hundred and forty-five thousand, two hundred naira (₦245,200.00 {US$595.15}).

Nondestructive Test on Typical Roadway Supports of a Mine via Drilling Core and Ground Penetrating Radar

2011 ◽  
Vol 368-373 ◽  
pp. 2411-2416
Author(s):  
Jian Ping Han ◽  
Hai Peng Liu
Keyword(s):  
Ground Penetrating Radar ◽  
Geological Structure ◽  
Surrounding Rock ◽  
Potential Threat ◽  
Real Performance ◽  
Design Requirements ◽  
And Performance ◽  
The Stability ◽  
Ground Penetrating ◽  
Drilling Core

Temporary or permanent supports are necessary in underground construction for maintaining the stability and limiting the damage of surrounding rock. Due to the uncertainty of geological structure, the specificity of the underground environment as well as other factors, the quality and performance of supporting structure are often difficult to satisfy the design requirements, which not only seriously affects the normal construction and operation of mines but also has the potential threat to the safety of underground production. In order to investigate the influence of the unfavorable geologic environment on supporting concrete and evaluate the real performance of roadway supports of a mine, 17 typical projects were chosen and the strength of supporting concrete was detected by nondestructive drilling core method. The result shows that the strength is widely less than the design value. Furthermore, 4 projects of them were investigated by the ground penetrating radar (GPR) in order to evaluate the feasibility of GPR in the performance investigation of the roadway supports of a mine. The results indicate that ground penetrating radar is capable of measuring the thickness of the support, the distribution of rebars and the defects of the surrounding rock.

A comparison of particle breakdown during chewing by guanacos (Lama guanicoe) and sheep

1998 ◽  
Vol 1998 ◽  
pp. 136-136
Author(s):  
M.D. Fraser ◽  
D.H. Baker
Keyword(s):  
Particle Size ◽  
Retention Time ◽  
Microbial Fermentation ◽  
Digestive Efficiency ◽  
Particle Size Reduction ◽  
Lama Guanicoe ◽  
Factors Influencing ◽  
Stomach Motility ◽  
Pass Through ◽  
Major Factors

To date, attempts to account for reported differences in digestive efficiency of camelids and ruminants have focused on factors such as stomach motility and the retention time of feed particles. The physical breakdown of forage into particles small enough to pass through the reticulo-omasal orifice is one of the major factors influencing the rate of passage of digesta from the reticulo-rumen in ruminants. Two of the main processes involved in particle size reduction are chewing (pre- and post-regurgitation) and microbial fermentation. While the characteristic vertical and horizontal jaw movement which occurs during mastication in the camelid is believed to allow for efficient use of the premolars and molars in cutting and grinding fibrous feeds, there have been no comparative studies to verify this, and to assess the contribution of chewing to differences in digestibility coefficients. The aim of this experiment was to directly compare particle breakdown during chewing by guanacos and sheep.

scholarly journals VLSI ARCHITECTURE OF PARALLEL MULTIPLIER– ACCUMULATOR BASED ON RADIX-2 MODIFIED BOOTH ALGORITHM

2012 ◽  
pp. 40-46
Author(s):  
Mr.M.V. Sathish ◽  
Mrs. Sailaja
Keyword(s):  
Signal Processing ◽  
High Speed ◽  
High Performance ◽  
Vlsi Architecture ◽  
Clock Frequency ◽  
Parallel Multiplier ◽  
Hybrid Type ◽  
Standard Design ◽  
Overall Performance ◽  
And Performance

A new architecture of multiplier-andaccumulator (MAC) for high-speed arithmetic. By combining multiplication with accumulation and devising a hybrid type of carry save adder (CSA), the performance was improved. Since the accumulator that has the largest delay in MAC was merged into CSA, the overall performance was elevated. The proposing method CSA tree uses 1’s-complement-based radix-2 modified Booth’s algorithm (MBA) and has the modified array for the sign extension in order to increase the bit density of the operands. The proposed MAC showed the superior properties to the standard design in many ways and performance twice as much as the previous research in the similar clock frequency. We expect that the proposed MAC can be adapted to various fields requiring high performance such as the signal processing areas.

Influence of the digestive/reproductive tract microbiota on chicken egg production beyond host genetics

2020 ◽  
Author(s):  
Diyan Li ◽  
Shilin Tian ◽  
Wei Zhu ◽  
Yuan Su ◽  
Tao Wang ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Egg Production ◽  
Reproductive Tract ◽  
Animal Health ◽  
Design Strategies ◽  
Host Genetics ◽  
Microbiome Composition ◽  
Chicken Egg ◽  
And Performance ◽  
Major Factors

Abstract Background: The microbiota of the digestive and reproductive systems has a prominent role in animal health and performance, but the extent of its contribution is difficult to determine. In chickens, the effect of host genetics on the reproductive and digestive tract microbiota is unclear, and the means by which digestive/reproductive microbiomes help improve egg production in chicken are unknown.Results: To gain insight into this, we examined genomes from 128 chickens reared under identical conditions and described their digestive (crop, gizzard and small intestine) and reproductive tract (vagina, uterus and isthmus) microbiota. Although the diversity, composition and predicted function of the digestive and reproductive tract microbiota exhibited notable microbiota variation substantially between different parts, host genetics had limited effects on the reproductive and digestive tract microbial community. The digestive and reproductive tract microbiota had a significant effect on egg production (accounting for 52.31% - 98.86% of the variance), after correcting for host genetic effects; in particular, the uterus and isthmus microbiota accounted for an average of 93.59% and 98.86%, respectively, of variance in egg production. We further identified four reproductive tract microbial species which were related to immune system, Bacteroides fragilis, Bacteroides salanitronis, Bacteroides barnesiae and Clostridium leptum, that were significantly positively correlated with egg production. Chickens with a lower abundance of these species had produced significantly fewer eggs at 300 days of age (37.13 vs. 113.75) than those with a higher abundance of these microorganisms. These taxa indicate potential roles play in promoting reproductive performance. Especially uterus and isthmus tract microbiota were major factors in regulating the chicken egg production.Conclusions: Host genetics has limited effect on digestive/reproductive microbiome composition. The distinct site-associated chicken microbiome may be determined by the differences of their physical function. These findings may help design strategies for controlling and altering the digestive/reproductive tract microbiota in chickens to improve egg production.

H∞ loop Shaping Robust Postprandial Glucose Control for Type 1 Diabetes

2021 ◽  
Vol 39 (2A) ◽  
pp. 268-279
Author(s):  
Safa F. Fadhel ◽  
Safanah M. Raafat
Keyword(s):  
Blood Glucose Concentration ◽  
Artificial Pancreas ◽  
Postprandial Glucose ◽  
Robust Controller ◽  
Control Effort ◽  
Loop Shaping ◽  
Design Requirements ◽  
And Performance

The Bergman model is one of the most commonly used models applied to the representation of the artificial pancreas (AP). It is important to study the effects of the insulin infusion on blood glucose concentration. This work includes a case study for the design of a robust controller for an AP. Robustness is a structured control that improves a system's ability to keep its stability and performance under various conditions. The proposed H∞ loop shaping HLS method will fulfill the design requirements of robust control and performance. The results of the simulation prove the superiority of the intended approach in terms of simple structure, robust performance, and stability with the least control effort

Viterbi Decoder in Hardware

2018 ◽  
pp. 6307-6318
Author(s):  
Mário Pereira Véstias
Keyword(s):  
Maximum Likelihood ◽  
Viterbi Algorithm ◽  
Viterbi Decoder ◽  
Maximum Likelihood Decoding ◽  
High Data ◽  
Design Requirements ◽  
Trellis Decoding ◽  
And Performance ◽  
Viterbi Decoders ◽  
Very High

Trellis decoding is used to recover encoded information that was corrupted during transmission over a noisy channel. The Viterbi algorithm is the most well known trellis-based maximum likelihood decoding algorithm. The Viterbi algorithm is executed by a Viterbi decoder. Different hardware solutions may be considered to implement a Viterbi decoder with different design requirements in terms of area, performance, power consumption, among others. The most appropriate solution depends on the metric requirements of the application as well as on the target technology. Properties of the Viterbi algorithm are used to simplify and improve the architecture of the Viterbi decoder. In particular, statistical properties of the Viterbi algorithm are used to design parallel Viterbi decoders with very high data decoding rates. The article focuses on the implementation of a Viterbi decoder in hardware, including optimizations to improve the area and performance.

An Integrated Product-Process Design Approach Considering Material Selection and Product Assembly

2020 ◽  
Vol 19 (04) ◽  
pp. 675-699
Author(s):  
Abadi Chaimae ◽  
Abadi Asmae ◽  
Manssouri Imad
Keyword(s):  
Process Design ◽  
Material Selection ◽  
Minimum Cost ◽  
Integrated Approach ◽  
Design Approach ◽  
Manufacturing Processes ◽  
Design Requirements ◽  
Product Assembly ◽  
Manufacturing Parameters

Nowadays, industries face very strong challenges because of the high competitiveness between them. In fact, they are required to offer products with high quality and minimum cost in the minimum time. Since most of the characteristics and costs of the product and its manufacturing process are fixed in the design phase, this paper is focused on this strategic phase. Indeed, a new integrated product design approach is presented. It considers at the same time design requirements, materials characteristics, manufacturing parameters and the assembly process specifications. The developed approach is quantitative. Actually, the decision making is based on all its steps on objective and subjective indicators. To validate the integrated approach, a case study on the Schrader Robot is developed. This application allows to choose the most appropriate materials, manufacturing processes and assembly solution of its different components.

Improvement of the process of removing phosphorus from high-phosphorus distillery effluent by ferric chloride using response surface methodology and three-step method

2019 ◽  
Vol 79 (11) ◽  
pp. 2046-2055
Author(s):  
Shengjian Li ◽  
Ting Lei ◽  
Fang Jiang ◽  
Changlin Miao ◽  
Xiangjun Yang ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Ferric Chloride ◽  
Quadratic Model ◽  
Phosphorus Concentration ◽  
Process Conditions ◽  
Distillery Effluent ◽  
Step Method ◽  
Standard Design ◽  
Major Factors

Abstract The purpose of this study was to optimize the coagulation–flocculation effect of a wastewater treatment system using the response surface methodology (RSM) and three-step method to minimize phosphorus concentration in the distillate wastewater. In order to minimize the concentration of total phosphorus (TP), experiments were carried out using -factorial designs with three levels and three factors. A Box–Behnken design, which is the standard design of RSM, was used to evaluate the effects and interactions of three major factors (Fe:P (w/w) ratio, coagulation pH and fast mixing speed (FMS)) on the treatment efficiency. A multivariable quadratic model developed for studying the response indicated that the values for optimum conditions for Fe:P (w/w) ratio, coagulation pH and FMS were 2.40, 6.48 and 100 rev min−1, respectively. Under optimal process conditions, the TP concentration in the distillery effluent was reduced from 10 mg L−1 to 0.215 mg L−1, representing a removal efficiency of 97.85%. Based upon the statistical evaluation of results, it is inferred that RSM can be used as an appropriate approach to optimize the coag-flocculation process. Meanwhile, the study has shown that, for the equivalent dose of ferric chloride, the average three-step effect is better than that of the one-time addition.

scholarly journals Porous asphalt concrete: A review of design, construction, performance and maintenance

2020 ◽  
Vol 13 (6) ◽  
pp. 601-612 ◽  
Author(s):  
Jian-Shiuh Chen ◽  
Chin Hung Yang
Keyword(s):  
Asphalt Concrete ◽  
Material Selection ◽  
Winter Maintenance ◽  
Porous Asphalt ◽  
Pavement Surface ◽  
Long Run ◽  
The World ◽  
And Performance ◽  
Porous Asphalt Concrete ◽  
Design Construction

AbstractPorous asphalt concrete (PAC) is an open-graded friction course that is specifically designed to have high air void contents for removing water from the pavement surface. PAC surfaces, which include open-graded friction courses, permeable friction courses, and drainage asphalt pavements, have increasingly gained acceptance among agencies and industry in the world. PAC might be susceptible to freeze-thaw damage in cold climates and require winter maintenance practices. The life span of PAC pavements shows a large variation depending on climates, traffic volumes and loadings, design and construction practices. The objective of this paper was to review design, construction, and performance that could maximize the advantages and minimize the disadvantages associated with the use of PAC mixtures. A consolidated review of the worldwide literature on PAC applications was conducted, with attention to the use of PAC in agency practices, and specifications for PAC from the world were evaluated. Based on an analysis of the results of this review, two key features were emphasized: (1) a recommended practice for material selection and design of PAC, and (2) a recommended practice for PAC construction and maintenance. Key points include a careful assessment of the PAC drainage and an adequate asphalt content to improve the performance of the pavement surface. A proper binder content stabilized by additives such as fibers and polymers is essential to ensure sufficient film thickness that is critical to the durability of the PAC mix in the long run.

scholarly journals Solar-driven evaporators for water treatment: challenges and opportunities

2021 ◽  
Vol 7 (1) ◽  
pp. 24-39
Author(s):  
Shao-Lin Wu ◽  
Honglei Chen ◽  
Hua-Li Wang ◽  
Xiaolan Chen ◽  
Hao-Cheng Yang ◽  
...  
Keyword(s):  
Water Treatment ◽  
Material Selection ◽  
Saline Water ◽  
Heat Management ◽  
Factors Affecting ◽  
Current Review ◽  
Challenges And Opportunities ◽  
Major Factors

Solar-driven evaporation is an emerging process to acquire freshwater from saline water or wastewater. The current review summarizes the major factors affecting the evaporation performance, including material selection, heat management, and scaling control.

Sign in / Sign up

Export Citation Format

Share Document