scholarly journals Dual-Level Capacitive Micromachined Uncooled Thermal Detector

Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5434 ◽  
Author(s):  
Hani H. Tawfik ◽  
Karim Allidina ◽  
Frederic Nabki ◽  
Mourad N. El-Gamal
Keyword(s):  
Integrated Circuits ◽  
Performance Comparison ◽  
The Other ◽  
Effective Length ◽  
Capacitance Change ◽  
Thermal Detector ◽  
Trade Off ◽  
Single Level ◽  
Level Design ◽  
Structural Layer

This paper presents a novel dual-level capacitive microcantilever-based thermal detector that is implemented in the commercial surface micromachined PolyMUMPs technology. The proposed design is implemented side-by-side with four different single-level designs to enable a design-to-design performance comparison. The dual-level design exhibits a rate of capacitance change per degree Celsius that is over three times higher than that of the single-level designs and has a base capacitance that is more than twice as large. These improvements are achieved because the dual-level architecture allows a 100% electrode-to-detector area, while single-level designs are shown to suffer from an inherent trade-off between sensitivity and base capacitance. In single-level designs, either the number of the bimorph beams or the capacitance electrode can be increased for a given sensor area. The former is needed for a longer effective length of the bimorph for higher thermomechanical sensitivity (i.e., larger tilting angels per degree Celsius), while the latter is desired to relax the read-out integrated-circuits requirements. This thermomechanical response-to-initial capacitance trade-off is mitigated by the dual-level design, which dedicates one structural layer to serve as the upper electrode of the detector, while the other layer contains as many bimorph beams as desired, independently of the former’s area.

scholarly journals Black Hole Algorithm for Sustainable Design of Counterfort Retaining Walls

2020 ◽  
Vol 12 (7) ◽  
pp. 2767 ◽  
Author(s):  
Víctor Yepes ◽  
José V. Martí ◽  
José García
Keyword(s):  
Black Hole ◽  
Sustainable Design ◽  
Retaining Walls ◽  
The Other ◽  
Trade Off ◽  
Construction Company ◽  
Geometric Variables ◽  
The Stability ◽  
The Cost ◽  
Black Hole Algorithm

The optimization of the cost and CO 2 emissions in earth-retaining walls is of relevance, since these structures are often used in civil engineering. The optimization of costs is essential for the competitiveness of the construction company, and the optimization of emissions is relevant in the environmental impact of construction. To address the optimization, black hole metaheuristics were used, along with a discretization mechanism based on min–max normalization. The stability of the algorithm was evaluated with respect to the solutions obtained; the steel and concrete values obtained in both optimizations were analyzed. Additionally, the geometric variables of the structure were compared. Finally, the results obtained were compared with another algorithm that solved the problem. The results show that there is a trade-off between the use of steel and concrete. The solutions that minimize CO 2 emissions prefer the use of concrete instead of those that optimize the cost. On the other hand, when comparing the geometric variables, it is seen that most remain similar in both optimizations except for the distance between buttresses. When comparing with another algorithm, the results show a good performance in optimization using the black hole algorithm.

Identifying opportunities for value chain development in the Kenyan coffee sector

2018 ◽  
Vol 47 (2) ◽  
pp. 150-159 ◽  
Author(s):  
Emerta Aragie
Keyword(s):  
Value Chain ◽  
Export Performance ◽  
Export Subsidy ◽  
The Other ◽  
Cash Crop ◽  
Trade Off ◽  
Cash Crops ◽  
Standard Value ◽  
Coffee Sector ◽  
Productivity Gains

By developing a model that describes the Kenyan coffee value chain, this study evaluates opportunities emanating from four scenarios representing productivity gains in the various value chain stages of the coffee sector and additional three scenarios reflecting shifts in market situations. Results show that productivity-enhancing policies have stronger effects on coffee output and export performance if they target the milling stage of the value chain. Export subsidy and favourable external marketing conditions also have stronger effects, distributed comparably across the various value chain stages. We, however, found that these gains in the coffee sector come at the expense of other cash crops such as cotton, tea, sugar and tobacco. The approach followed in this study is relevant as this trade-off between coffee and the other cash crop sectors may not be visibly shown using standard value chain approaches.

Practical Aspects of Propulsion Shaft Alignment

2021 ◽  
Author(s):  
Kyriakos Avgouleas ◽  
Emmanouil Sarris ◽  
George Gougoulidis
Keyword(s):  
Cost Effectiveness ◽  
Numerical Model ◽  
High Speed ◽  
The Other ◽  
Technical Literature ◽  
Trade Off ◽  
Fea Model ◽  
Shaft Alignment ◽  
Alignment Strategy ◽  
Potential Damage

The economical and operational implications of poor alignment are indisputable for the propulsion shafting system of a commercial vessel. This holds true for naval vessels as well, although far less documented in the technical literature. This paper addresses some of the challenges associated with the proper alignment of a high-speed naval craft, which has been in service for many years. Laser bore-sighting was performed on a Guided Missile Fast Patrol Boat resting on a docking cradle. The measured bearing offsets were input to a FEA model of the shafting system to calculate bearing reactions and detect potential misalignment issues. Subsequent decisions regarding corrective measures take into account the results computed by the numerical model, experience from sister ships, the available documentation from the building yard and several other factors which are discussed in the paper. The solutions proposed are targeted towards a balanced trade-off between cost effectiveness and out-of-service time on one hand, and the risk of potential damage from misalignment on the other hand, which would seriously disrupt the ship’s operational availability. Practical aspects and lessons identified in the process are also presented, which demonstrate the distinct differences in alignment strategy of a high-speed naval craft compared to a typical commercial vessel.

Performance comparison between dual cantilevered and touch based hybridized triboelectric harvesters

2021 ◽  
Vol 15 (1) ◽  
pp. 7754-7761
Author(s):  
Satish Rao Ganapathy ◽  
H. Salleh
Keyword(s):  
Low Power ◽  
Surface Area ◽  
Peak Power ◽  
Energy Harvester ◽  
Dissimilar Materials ◽  
Performance Comparison ◽  
Effective Length ◽  
Surface Charges ◽  
Generate Surface ◽  
Power Outputs

The demand for energy harvesting technologies has been increasing over the years attributed to its significance to low power applications. One of the key problems associated with the vibration-based harvester is the fact that these harvesters generate low usable power while maximum peak power can only be attained when the device frequency matches the source frequency. In this study, triboelectric mechanism was investigated in combination with the piezoelectric mechanism in order to enhance the performance of the harvester. Triboelectric mechanism functions in a way that two dissimilar materials were placed in contact and then separated in order to generate surface charges and electric potential between them. Main design factors such as materials, surface area, structure, effective length, and etc. play a significant part in the enhancement of the performance. This study proposed two distinct designs of dual cantilevered structure and touch-based triboelectric energy harvester and evaluated the efficiency of the output between both structures. In addition, the effect of extension and surface area of triboelectric materials was investigated while the influence of these factors on the performance of the harvester was evaluated. The highest value of peak power obtained for dual cantilevered hybrid harvester was 650 µW across a load of 160 kΩ and frequency of 26 Hz. On the other hand, touch-based energy harvester produced an output peak power of 1220 µW across a load of 400 kΩ at 25 Hz. Achieving these power outputs may be able to power up electronics such as smartwatches, hearing aid and etc. Future studies on reliable low power applications to further advance the green power technology will be investigated.

COMPUTING THE RUPTURE DEGREE IN COMPOSITE GRAPHS

2010 ◽  
Vol 21 (03) ◽  
pp. 311-319 ◽  
Author(s):  
AYSUN AYTAC ◽  
ZEYNEP NIHAN ODABAS
Keyword(s):  
Complete Graph ◽  
Connected Graph ◽  
The Other ◽  
Trade Off ◽  
Number Of Components ◽  
Np Complete ◽  
Work Done ◽  
Better Than

The rupture degree of an incomplete connected graph G is defined by [Formula: see text] where w(G - S) is the number of components of G - S and m(G - S) is the order of a largest component of G - S. For the complete graph Kn, rupture degree is defined as 1 - n. This parameter can be used to measure the vulnerability of a graph. Rupture degree can reflect the vulnerability of graphs better than or independent of the other parameters. To some extent, it represents a trade-off between the amount of work done to damage the network and how badly the network is damaged. Computing the rupture degree of a graph is NP-complete. In this paper, we give formulas for the rupture degree of composition of some special graphs and we consider the relationships between the rupture degree and other vulnerability parameters.

scholarly journals Partner Uncertainty and the Dynamic Boundary of the Firm

2017 ◽  
Vol 9 (4) ◽  
pp. 277-302 ◽  
Author(s):  
Thomas Hellmann ◽  
Veikko Thiele
Keyword(s):  
Asset Specificity ◽  
The Other ◽  
Trade Off ◽  
Specific Investments ◽  
Dynamic Boundary ◽  
Ex Post ◽  
Ex Ante

We develop a new theory of the dynamic boundary of the firm where asset owners may want to change partners ex post. We identify a fundamental trade-off between (i) a “displacement externality” under non-integration, where a partner leaves a relationship even though his benefit is worth less than the loss to the displaced partner, and (ii) a “retention externality” under integration, where a partner inefficiently retains the other. With more asset specificity, displacement externalities matter more and retention externalities less, so that integration becomes more attractive. Wealth can resolve ex post inefficient partner arrangements, but may weaken ex ante incentives for specific investments. (JEL D21, D23, D25, D62, D86, G31)

scholarly journals Hosting models comparison of ASP.NET Core application

2018 ◽  
Vol 8 ◽  
pp. 258-262
Author(s):  
Kamil Zdanikowski ◽  
Beata Pańczyk
Keyword(s):  
Standard Model ◽  
Performance Comparison ◽  
The Other ◽  
Models Comparison ◽  
Test Scenarios

The article presents hosting models comparison of ASP.NET Core application. Available hosting models were described and compared and then performance comparison was carried out. For each model the same test scenarios were executed and their performance was determined by number of requests per second which host was able to process. The results obtained show that standard model is the least efficient one and using one of the other configurations, for example, IIS with Kestrel (in-process), Kestrel or HTTP.sys might provide even several times better performance compared to standard model.

The effect of leguminous plant species onCallosobruchus maculatus(Coleoptera: Bruchidae) and its egg parasitoidUscana lariophaga(Hymenoptera: Trichogrammatidae)

1998 ◽  
Vol 88 (1) ◽  
pp. 93-99 ◽  
Author(s):  
A. van Huis ◽  
M. de Rooy
Keyword(s):  
Sex Ratio ◽  
Plant Species ◽  
Nutritional Quality ◽  
Development Time ◽  
Callosobruchus Maculatus ◽  
Egg Parasitoid ◽  
The Other ◽  
Leguminous Plant ◽  
Trade Off ◽  
Storage Pest

AbstractThe performance of the egg parasitoidUscana lariophagaSteffan was studied when reared on eggs of the bruchid storage pest,Callosobruchus maculatus(Fabricius) developing in seeds of cowpea, chickpea and pigeonpea. The beetle laid more and larger eggs on pigeonpea than on cowpea and chickpea, indicating that there was not a trade-off between number and size of the eggs. The bruchid larvae reared on pigeonpea exhibited a longer development time and a higher mortality than those reared on cowpea and chickpea. The resulting males weighed less than those reared on cowpea and chickpea. The trichogrammatidU. lariophagaparasitized more eggs whenC. maculatuswas reared on chickpea than when reared on the other hosts. Parasitoid larvae developed slowest and had the highest mortality in eggs ofC. maculatusreared on pigeonpea compared to those reared on cowpea and chickpea; the sex ratio (% of females) of the resulting adults was also higher. The high mortality and long development time ofC. maculatusreared on pigeonpea indicated that this legume was less favourable toC. maculatusthan chickpea or cowpea. This was probably also true for the parasitoid since the mortality was higher and development longer in eggs ofC. maculatusreared on pigeonpea compared to those reared on cowpea and chickpea. Therefore, when host eggs were larger and of lower nutritional quality, the proportion of female egg parasitoids was greater.

scholarly journals Plasmodium infection decreases fecundity and increases survival of mosquitoes

2012 ◽  
Vol 279 (1744) ◽  
pp. 4033-4041 ◽  
Author(s):  
J. Vézilier ◽  
A. Nicot ◽  
S. Gandon ◽  
A. Rivero
Keyword(s):  
Life History ◽  
Insecticide Resistance ◽  
Life History Traits ◽  
Experimental System ◽  
Adaptive Strategy ◽  
Genetic Variations ◽  
The Other ◽  
Plasmodium Infection ◽  
Trade Off ◽  
The One

Long-lived mosquitoes maximize the chances of Plasmodium transmission. Yet, in spite of decades of research, the effect of Plasmodium parasites on mosquito longevity remains highly controversial. On the one hand, many studies report shorter lifespans in infected mosquitoes. On the other hand, parallel (but separate) studies show that Plasmodium reduces fecundity and imply that this is an adaptive strategy of the parasite aimed at redirecting resources towards longevity. No study till date has, however, investigated fecundity and longevity in the same individuals to see whether this prediction holds. In this study, we follow for both fecundity and longevity in Plasmodium- infected and uninfected mosquitoes using a novel, albeit natural, experimental system. We also explore whether the genetic variations that arise through the evolution of insecticide resistance modulate the effect of Plasmodium on these two life-history traits. We show that (i) a reduction in fecundity in Plasmodium- infected mosquitoes is accompanied by an increase in longevity; (ii) this increase in longevity arises through a trade-off between reproduction and survival; and (iii) in insecticide-resistant mosquitoes, the slope of this trade-off is steeper when the mosquito is infected by Plasmodium (cost of insecticide resistance).

Design and Analysis of an N-Path Filter with High Out-of-Band Rejection Using Feed-Forward Technique

2019 ◽  
Vol 28 (03) ◽  
pp. 1950053 ◽  
Author(s):  
Amin Mohammadpour ◽  
Abdolreza Nabavi
Keyword(s):  
Phase Noise ◽  
Insertion Loss ◽  
The Other ◽  
Trade Off ◽  
Feed Forward ◽  
Main Path

This paper presents an N-path filter with high out-of-band rejection using feed-forward technique. The structure utilizes two four-path filters, one as the main-path and the other as auxiliary-path, and two TIAs to increase the order of the filter from two to four. As a result of this, and due to using two series resistors in the main path, the out-of-band rejection is significantly improved. Analysis and simulations show that the series resistors can be chosen such that the NF degradation is below 2[Formula: see text]dB while the out-of-band rejection is improved by about 20[Formula: see text]dB. Therefore, the trade-off between the insertion-loss and out-of-band rejection is relaxed compared to conventional N-path filter. Also, it is shown that decreasing the size of baseband capacitors improves the NF of the filter. The effect of clock phase-noise on NF of the filter in the presence of strong out-of-band blocker is modeled and simulated.

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