scholarly journals An Equilibrium Desorption Model for the Strength and Extraction Yield of Full Immersion Brewed Coffee

2020 ◽  
Author(s):  
Jiexin Liang ◽  
Ka Chun Chan ◽  
William Ristenpart
Keyword(s):  
Single Species ◽  
Extraction Yield ◽  
Strongly Correlated ◽  
Precise Control ◽  
True Value ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Sensory Qualities ◽  
Full Immersion ◽  
Desorption Model

Abstract The sensory qualities of brewed coffee are strongly correlated with the total dissolved solids (TDS) and extraction yield (E) of the brew. Here, we derive a predictive model for the TDS and E of full immersion brewed coffee using a pseudo-equilibrium desorption approach. Assuming a single, species-averaged equilibrium constant K yields theoretical predictions indicating that the TDS is approximately inversely proportional to the water/coffee mass brew ratio, while E is independent of the brew ratio. Our experimental results strongly accord with both theoretical predictions, and indicate that E is approximately 21% over a wide range of brew ratios. An analysis of the standard oven-drying method for measuring E indicates that it yields significant underestimates of the true value at equilibrium, due to retained brew within the spent moist grounds. We further demonstrate that K is insensitive to grind size, roast level, and brew temperature over the range 80-99°C. Taken together, our results indicate that full immersion brewing offers precise control over the TDS at equilibrium but little control over E, and that practitioners should pay careful attention to their brew ratio as the most important parameter for full-immersion brewing.

scholarly journals An equilibrium desorption model for the strength and extraction yield of full immersion brewed coffee

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiexin Liang ◽  
Ka Chun Chan ◽  
William D. Ristenpart
Keyword(s):  
Single Species ◽  
Extraction Yield ◽  
Strongly Correlated ◽  
Precise Control ◽  
True Value ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Sensory Qualities ◽  
Full Immersion ◽  
Desorption Model

AbstractThe sensory qualities of brewed coffee are known to be strongly correlated with the total dissolved solids (TDS) and extraction yield (E) of the brew. Here, we derive a predictive model for the TDS and E of full immersion brewed coffee using a pseudo-equilibrium desorption approach. Assuming a single, species-averaged equilibrium constant $$K$$ K yields theoretical predictions indicating that the TDS is approximately inversely proportional to the water/coffee mass brew ratio, while E is independent of the brew ratio. Our experimental results strongly accord with both theoretical predictions, and indicate that E is approximately 21% over a wide range of brew ratios. An analysis of the standard oven-drying method for measuring E indicates that it yields significant underestimates of the true value at equilibrium, due to retained brew within the spent moist grounds. We further demonstrate that $$K$$ K is insensitive to grind size, roast level, and brew temperature over the range 80–99 °C. Taken together, our results indicate that full immersion brewing offers precise control over the TDS at equilibrium but little control over E, and that practitioners should pay careful attention to their brew ratio as the most important parameter for full-immersion brewing.

QCD at Fixed Order: Processes

2018 ◽  
Author(s):  
John Campbell ◽  
Joey Huston ◽  
Frank Krauss
Keyword(s):  
Hadron Collider ◽  
Detailed Comparison ◽  
Theoretical Description ◽  
Higgs Bosons ◽  
Final States ◽  
Collider Physics ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Fixed Order ◽  
The Subject

At the core of any theoretical description of hadron collider physics is a fixed-order perturbative treatment of a hard scattering process. This chapter is devoted to a survey of fixed-order predictions for a wide range of Standard Model processes. These range from high cross-section processes such as jet production to much more elusive reactions, such as the production of Higgs bosons. Process by process, these sections illustrate how the techniques developed in Chapter 3 are applied to more complex final states and provide a summary of the fixed-order state-of-the-art. In each case, key theoretical predictions and ideas are identified that will be the subject of a detailed comparison with data in Chapters 8 and 9.

Modal frequencies of bridges from GNSS (GPS) monitoring data: Experimental, statistical evidence

2021 ◽  
Vol 17 (1-2) ◽  
pp. 3-14
Author(s):  
Stathis C. Stiros ◽  
F. Moschas ◽  
P. Triantafyllidis
Keyword(s):  
Signal To Noise Ratio ◽  
Vertical Axis ◽  
Bridge Monitoring ◽  
Low Snr ◽  
True Value ◽  
Gps Satellites ◽  
Wide Range ◽  
Spectral Peaks ◽  
Monitoring Survey ◽  
True Frequency

GNSS technology (known especially for GPS satellites) for measurement of deflections has proved very efficient and useful in bridge structural monitoring, even for short stiff bridges, especially after the advent of 100 Hz GNSS sensors. Mode computation from dynamic deflections has been proposed as one of the applications of this technology. Apart from formal modal analyses with GNSS input, and from spectral analysis of controlled free attenuating oscillations, it has been argued that simple spectra of deflections can define more than one modal frequencies. To test this scenario, we analyzed 21 controlled excitation events from a certain bridge monitoring survey, focusing on lateral and vertical deflections, recorded both by GNSS and an accelerometer. These events contain a transient and a following oscillation, and they are preceded and followed by intervals of quiescence and ambient vibrations. Spectra for each event, for the lateral and the vertical axis of the bridge, and for and each instrument (GNSS, accelerometer) were computed, normalized to their maximum value, and printed one over the other, in order to produce a single composite spectrum for each of the four sets. In these four sets, there was also marked the true value of modal frequency, derived from free attenuating oscillations. It was found that for high SNR (signal-to-noise ratio) deflections, spectral peaks in both acceleration and displacement spectra differ by up to 0.3 Hz from the true value. For low SNR, defections spectra do not match the true frequency, but acceleration spectra provide a low-precision estimate of the true frequency. This is because various excitation effects (traffic, wind etc.) contribute with numerous peaks in a wide range of frequencies. Reliable estimates of modal frequencies can hence be derived from deflections spectra only if excitation frequencies (mostly traffic and wind) can be filtered along with most measurement noise, on the basis of additional data.

scholarly journals Sequence data from isolated lichen-associated melanized fungi enhance delimitation of two new lineages within Chaetothyriomycetidae

2021 ◽  
Vol 20 (7) ◽  
pp. 911-927
Author(s):  
Lucia Muggia ◽  
Yu Quan ◽  
Cécile Gueidan ◽  
Abdullah M. S. Al-Hatmi ◽  
Martin Grube ◽  
...  
Keyword(s):  
Sequence Data ◽  
Single Species ◽  
Sister Group ◽  
Asexual Propagation ◽  
Dna Sequence Data ◽  
Wide Range ◽  
The Family ◽  
Rock Inhabiting Fungi ◽  
Stable Habitat

AbstractLichen thalli provide a long-lived and stable habitat for colonization by a wide range of microorganisms. Increased interest in these lichen-associated microbial communities has revealed an impressive diversity of fungi, including several novel lineages which still await formal taxonomic recognition. Among these, members of the Eurotiomycetes and Dothideomycetes usually occur asymptomatically in the lichen thalli, even if they share ancestry with fungi that may be parasitic on their host. Mycelia of the isolates are characterized by melanized cell walls and the fungi display exclusively asexual propagation. Their taxonomic placement requires, therefore, the use of DNA sequence data. Here, we consider recently published sequence data from lichen-associated fungi and characterize and formally describe two new, individually monophyletic lineages at family, genus, and species levels. The Pleostigmataceae fam. nov. and Melanina gen. nov. both comprise rock-inhabiting fungi that associate with epilithic, crust-forming lichens in subalpine habitats. The phylogenetic placement and the monophyly of Pleostigmataceae lack statistical support, but the family was resolved as sister to the order Verrucariales. This family comprises the species Pleostigma alpinum sp. nov., P. frigidum sp. nov., P. jungermannicola, and P. lichenophilum sp. nov. The placement of the genus Melanina is supported as a lineage within the Chaetothyriales. To date, this genus comprises the single species M. gunde-cimermaniae sp. nov. and forms a sister group to a large lineage including Herpotrichiellaceae, Chaetothyriaceae, Cyphellophoraceae, and Trichomeriaceae. The new phylogenetic analysis of the subclass Chaetothyiomycetidae provides new insight into genus and family level delimitation and classification of this ecologically diverse group of fungi.

SIMULATION OF AN AXISYMMETRIC RISING BUBBLE BY A MULTIPLE RELAXATION TIME LATTICE BOLTZMANN METHOD

2009 ◽  
Vol 23 (24) ◽  
pp. 4907-4932 ◽  
Author(s):  
ABBAS FAKHARI ◽  
MOHAMMAD HASSAN RAHIMIAN
Keyword(s):  
Free Surface ◽  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Rise Velocity ◽  
Rising Bubble ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Multiple Relaxation Time ◽  
Bubble Rising ◽  
Boltzmann Method

In this paper, the lattice Boltzmann method is employed to simulate buoyancy-driven motion of a single bubble. First, an axisymmetric bubble motion under buoyancy force in an enclosed duct is investigated for some range of Eötvös number and a wide range of Archimedes and Morton numbers. Numerical results are compared with experimental data and theoretical predictions, and satisfactory agreement is shown. It is seen that increase of Eötvös or Archimedes number increases the rate of deformation of the bubble. At a high enough Archimedes value and low Morton numbers breakup of the bubble is observed. Then, a bubble rising and finally bursting at a free surface is simulated. It is seen that at higher Archimedes numbers the rise velocity of the bubble is greater and the center of the free interface rises further. On the other hand, at high Eötvös values the bubble deforms more and becomes more stretched in the radial direction, which in turn results in lower rise velocity and, hence, lower elevations for the center of the free surface.

scholarly journals On the Effectiveness of Sampling for Evolutionary Optimization in Noisy Environments

2018 ◽  
Vol 26 (2) ◽  
pp. 237-267 ◽  
Author(s):  
Chao Qian ◽  
Yang Yu ◽  
Ke Tang ◽  
Yaochu Jin ◽  
Xin Yao ◽  
...  
Keyword(s):  
Negative Impact ◽  
Fitness Function ◽  
Evolutionary Optimization ◽  
Function Evaluation ◽  
Noisy Optimization ◽  
Running Time ◽  
Analysis And Design ◽  
True Value ◽  
Wide Range ◽  
The Impact

In real-world optimization tasks, the objective (i.e., fitness) function evaluation is often disturbed by noise due to a wide range of uncertainties. Evolutionary algorithms are often employed in noisy optimization, where reducing the negative effect of noise is a crucial issue. Sampling is a popular strategy for dealing with noise: to estimate the fitness of a solution, it evaluates the fitness multiple ([Formula: see text]) times independently and then uses the sample average to approximate the true fitness. Obviously, sampling can make the fitness estimation closer to the true value, but also increases the estimation cost. Previous studies mainly focused on empirical analysis and design of efficient sampling strategies, while the impact of sampling is unclear from a theoretical viewpoint. In this article, we show that sampling can speed up noisy evolutionary optimization exponentially via rigorous running time analysis. For the (1[Formula: see text]1)-EA solving the OneMax and the LeadingOnes problems under prior (e.g., one-bit) or posterior (e.g., additive Gaussian) noise, we prove that, under a high noise level, the running time can be reduced from exponential to polynomial by sampling. The analysis also shows that a gap of one on the value of [Formula: see text] for sampling can lead to an exponential difference on the expected running time, cautioning for a careful selection of [Formula: see text]. We further prove by using two illustrative examples that sampling can be more effective for noise handling than parent populations and threshold selection, two strategies that have shown to be robust to noise. Finally, we also show that sampling can be ineffective when noise does not bring a negative impact.

A review of the Afrotropical sand tampan, Ornithodoros savignyi: a complex species.

2021 ◽  
Vol 16 (036) ◽  
Author(s):  
Roxanne Albertha Charles
Keyword(s):  
Species Complex ◽  
Single Species ◽  
Biological Molecules ◽  
Soft Tick ◽  
Complex Species ◽  
Lake Chad ◽  
Ornithodoros Savignyi ◽  
Morphological Studies ◽  
Biological Studies ◽  
Wide Range

Abstract The sand tampan, Ornithodoros savignyi (Audouin, 1827), is an economically important soft tick of the Afrotropics parasitising a wide range of livestock and humans. These ticks are known to inflict painful bites which may be fatal in susceptible hosts. Historically thought to be a single species, Ornithodoros savignyi is now considered to be a complex of four tick subspecies based on molecular and morphological studies. They include Ornithodoros (Ornithodoros) kalahariensis, O. (O.) pavimentosus, O. (O.) noorsveldensis and O. (O.) savignyi. As such there may be significant implications for previous biological studies conducted on this tick. Therefore, for the purposes of this review, sand tampan toxicosis and potentially useful biological molecules have been discussed for O. (O.) savignyi sensu lato since most reported work was based on ticks collected from the Kalahari and Lake Chad region. An overview of the host range and vector biology for the O. (O.) savignyi species complex will also be examined.

Occurrence and Significance of Toxic Cyanobacteria in Southern Africa

1991 ◽  
Vol 23 (1-3) ◽  
pp. 175-180 ◽  
Author(s):  
W. E. Scott
Keyword(s):  
South Africa ◽  
Southern Africa ◽  
Single Species ◽  
Practical Significance ◽  
Toxic Species ◽  
Toxic Cyanobacteria ◽  
Cyanobacterial Species ◽  
Wide Range ◽  
Toxic Blooms ◽  
Different Parts

A comprehensive list is provided of more than forty cyanobacterial species and genera reported to have toxic properties. In South Africa the majority of animal poisonings since 1927 have been caused by a single species Microcystis aeruginosa. Although other toxic species also occur in southern Africa, to date they have been of little practical significance. The widespread distribution of M. aeruginosa throughout southern Africa indicates a tremendous potential for toxic blooms to develop with increasing eutrophication. Using HPLC techniques up to six different toxin variants have been quantified in natural blooms of M. aeruginosa collected in different parts of South Africa. The amounts and proportions of the different toxins in the different samples varied over a wide range. Several additional unidentified toxins were detected.

Identifying Terrorists using Banking Data

2012 ◽  
Vol 12 (3) ◽  
Author(s):  
Steven D. Levitt
Keyword(s):  
Retail Banking ◽  
Demographic Characteristics ◽  
Strongly Correlated ◽  
The Real ◽  
Administrative Records ◽  
Wide Range ◽  
Intelligence Agencies ◽  
Out Of Sample ◽  
And Behaviors

Abstract The fight against terrorism requires identifying potential terrorists before they have the opportunity to act. In this paper, we investigate the extent to which retail banking data – which as far as we know are not currently used by anti-terror intelligence agencies in any systematic manner – are a useful tool in identifying terrorists. Using detailed administrative records of a large British bank, we demonstrate that a number of variables in the data are strongly correlated with terrorism-related activities. Having both an Islamic given name and surname, not surprisingly, are among the strongest of these predictors, but a wide range of other demographic characteristics and behaviors observed in the data are also correlated strongly with terrorist involvement. The real key to our method, however, rests on the identification of one particular pattern of banking behavior (what we call “Variable Z”) which dramatically improves our ability to identify terrorists. Our model is demonstrated to have substantial power to identify terrorists both within sample and out of sample.

Observer-based nonlinear precise control of pneumatic servo systems

2018 ◽  
Vol 233 (2) ◽  
pp. 165-176 ◽  
Author(s):  
Sepehr Ramezani ◽  
Keivan Baghestan
Keyword(s):  
Sliding Mode ◽  
Nonlinear Modeling ◽  
High Gain ◽  
Good Choice ◽  
Servo Systems ◽  
Precise Position ◽  
Precise Control ◽  
Automation Systems ◽  
Wide Range ◽  
The Cost

Pneumatic systems are used in a wide range of industrial robotic and automation systems due to their interesting properties. However, air compressibility, friction, and the other nonlinear characteristics of a servo pneumatic system are difficulties, which contribute to use modern controllers. Conventional linear controllers face steady-state error and uncertainty. Nonlinear modeling with model-based control is a good choice to deal with this problem. In this paper, behavior equation of flow and pressure, friction, and other nonlinear factors are studied. Afterward to reach precise position tracking and low steady error, sliding mode control is proposed. In this way, measurement of pressures and other states of system is required. To reduce the cost of using pressure sensor, observation of pressure with nonlinear high gain observer is suggested. It was seen that the new proposed approach solved the observability problem of servo pneumatic systems. Pressure signal of each sides of cylinder are observed simultaneously by measurement of piston position. Finally, stability of designed controller is studied in the presence of observed states. Experimental results validate the advantage of using designed controller-observer instead of conventional proportional–integral–derivative controller with different input signals in the presence of high friction actuator.

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