scholarly journals Kinetic aspects of a dried thin layer carrot in a heat pump dryer

DYNA ◽  
2016 ◽  
Vol 83 (195) ◽  
pp. 16-20 ◽  
Author(s):  
Juan Carlos Gómez-Daza ◽  
Claudia Isabel Ochoa-Martínez
Keyword(s):  
Thin Layer ◽  
Heat Pump ◽  
Goodness Of Fit ◽  
Statistical Tests ◽  
Effective Diffusivity ◽  
Empirical Models ◽  
Sample Thickness ◽  
Air Velocity ◽  
Relative Moisture ◽  
Chi Squared

This article presents a mathematical model for drying thin layer carrot slices (Daucus carota) using a heat pump dryer (HPD). To select the equation that best describes the drying curve, 10 semi-theoretical and/or empirical models were evaluated. The parameters were determined using the Sigma-Plot® program, and their goodness of fit was compared using the correlation coefficient, R<sup>2</sup>; Chi-squared, <span style="font-family: symbol;">C</span><sup>2</sup>; standard error of the estimate (SEE) and root mean square error (RMSE). Additionally, the effect of the relative moisture, sample thickness and air velocity on the effective diffusivity of the process was evaluated using a response surface tool. Although all the models correctly fit the experimental data, based on the statistical tests, the Wang-Singh model was selected as the best.

scholarly journals Statistical Analysis of Numerical Preclinical Radiobiological Data

2016 ◽  
Author(s):  
Helene Hill ◽  
Joel H Pitt
Keyword(s):  
Goodness Of Fit ◽  
Statistical Tests ◽  
Numerical Data ◽  
Image Manipulation ◽  
Data Sets ◽  
Scientific Fraud ◽  
Grant Applications ◽  
Chi Squared ◽  
Chance Occurrence ◽  
Vexing Problem

<p><strong>Background: </strong>Scientific fraud is an increasingly vexing problem.&nbsp; Many current programs for fraud detection focus on image manipulation, while techniques for detection based on anomalous patterns that may be discoverable in the underlying numerical data&nbsp; get much less attention, even though these techniques are often easy to apply.&nbsp;</p><p><strong>Methods: </strong>We applied statistical techniques in considering and comparing data sets from ten researchers in one laboratory and three outside investigators to determine whether anomalous patterns in data from a research teaching assistant (RTS) were likely to have occurred by chance. Rightmost digits of values in RTS data sets were not, as expected, uniform; equal pairs of terminal digits occurred at higher than expected frequency (&gt; 10%); and, an unexpectedly large number of data triples commonly produced in such research included values near their means as an element. We applied standard statistical tests (chi-squared goodness of fit, binomial probabilities) to determine the likelihood of the first two anomalous patterns, and developed a new statistical model to test the third.</p><p><strong>&nbsp;Results: </strong>Application of the three tests to various data sets reported by RTS resulted in repeated rejection of the hypotheses (often at p-levels well below 0.001) that anomalous patterns in those data may have occurred by chance.&nbsp; Similar application to data sets from other investigators were entirely consistent with chance occurrence.</p><p><strong>Conclusions: </strong>This analysis emphasizes the importance of access to raw data that form the bases of publications, reports and grant applications in order to evaluate the correctness of the conclusions, and the importance of applying statistical methods to detect anomalous, especially potentially fabricated, numerical results.&nbsp;</p>

Thin-Layer Drying Characteristics and Modeling of Paper Sludge

2012 ◽  
Vol 190-191 ◽  
pp. 575-580
Author(s):  
Han Min Xiao
Keyword(s):  
Goodness Of Fit ◽  
Effective Diffusivity ◽  
Empirical Models ◽  
Coefficient Of Determination ◽  
Paper Sludge ◽  
Mean Square ◽  
Statistical Parameters ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Drying Conditions

In this paper, the drying experiments of paper sludge were performed at different drying conditions. The drying kinetics and phenomena of paper sludge were investigated. The effective diffusivity and the activation energy of the paper sludge during drying had been evaluated. At the same time, seven empirical models were used to model the experimental data, such as Newton, Page, Modified Page, Henderson and Pabis, Logarithmic, Two term, Two Term exponential et al. Three statistical parameters (The coefficient of determination (R2), root mean square error (RMSE) and the residual sum of square (RSS) ) were used to evaluate goodness of fit of the tested models.

scholarly journals Experimental Study and Mathematical Modeling of Convective Thin-Layer Drying of Apple Slices

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1562
Author(s):  
Mohammad Jafar Royen ◽  
Abdul Wasim Noori ◽  
Juma Haydary
Keyword(s):  
Mathematical Modeling ◽  
Experimental Study ◽  
Thin Layer ◽  
Water Activity ◽  
Empirical Models ◽  
Slice Thickness ◽  
Air Humidity ◽  
Air Velocity ◽  
Apple Slices ◽  
Product Water

This work represents an experimental study and mathematical modeling of convective apple slice drying. The influence of multiple process parameters such as temperature, air humidity, air velocity and slice thickness on process kinetics, product water activity and parameters of empirical models has been investigated. Drying characteristics of apple slices were monitored at temperatures of 40, 45 and 50 °C, air velocities of 0.6, 0.85 and 1.1 m/s., slice thicknesses of 4, 6, 8, 10 and 12 mm, and in relative air humidity ranges of 25–28, 35–38 and 40–45%. During the process, samples were dried from an initial moisture content of 86.7% to that of 20% (w.b), corresponding to product water activity of 0.45 ± 0.05. By increasing the temperature from 40 to 50 °C, the time for reaching the required product water activity decreased by about 300 min. Sample thickness is the most significant parameter; by increasing the slice thickness from 4 to 12 mm, the time required to achieve the required water activity increased by more than 500 min. For all experimental runs, parameters of five different thin-layer empirical models were estimated. A thin-layer model sensible to process conditions such as temperature, air velocity, layer thickness and air relative humidity was developed and statistically analyzed.

scholarly journals Modeling of thin layer drying characteristics of “Xiem” banana peel cultivated at U Minh district, Ca Mau province, Vietnam

Food Research ◽  
2021 ◽  
Vol 5 (5) ◽  
pp. 244-249
Author(s):  
N.V. Tai ◽  
M.N. Linh ◽  
N.M. Thuy
Keyword(s):  
Activation Energy ◽  
Thin Layer ◽  
Goodness Of Fit ◽  
Effective Diffusivity ◽  
Coefficient Of Determination ◽  
Banana Peel ◽  
Drying Rate ◽  
Drying Process ◽  
Drying Temperature ◽  
Thin Layer Drying

In Vietnam, banana peels have been discarded as waste which is a potential source of raw material for food and other bioprocessing industries. Drying the peel offers opportunities for value addition into novel products, thus reducing waste from the fruit processing operations. This study presented the mathematical models of the thin-layer drying behaviour of banana peels using three air temperatures (60oC, 70oC and 80oC). The effect of drying temperature on the reduction of moisture content and drying rate of the banana peel was evaluated. A total of eight commonly drying models were used for choosing the best fitness model for describing the oven drying process. The effective moisture diffusivity and activation energy were calculated using Fick’s diffusion equation. The obtained results showed that increasing drying temperature accelerate the drying process, as well as, increasing drying rate and effective diffusivity. The goodness of fit tests base on the criterion indicated that the Page model gave the best fit to experimental results. The effective diffusivity varied from 2.29×10-8 – 3.25×10-8 m 2 /s. Effective diffusivity was satisfactorily by an Arrhenius relationship with activation energy within the 60-80°C temperature range. The obtained activation energy was 16.98 kJ/mol with a high coefficient of determination (R2 = 0.903).

Thin Layer Modeling of Tom Yum Herbs in Vacuum Heat Pump Dryer

2010 ◽  
Vol 16 (2) ◽  
pp. 135-146 ◽  
Author(s):  
A. Artnaseaw ◽  
S. Theerakulpisut ◽  
C. Benjapiyaporn
Keyword(s):  
Thin Layer ◽  
Heat Pump ◽  
Statistical Tests ◽  
Experimental Results ◽  
Coefficient Of Determination ◽  
Chi Square ◽  
Drying Temperature ◽  
Thin Layer Drying ◽  
Drying Models ◽  
Good Agreement

Thin layer vacuum heat pump drying experiments were conducted to determine drying models for Tom Yum herbs (chili, lemon grass, kaffir lime leaf and galangal slice). The drying experiments were conducted in a vacuum heat pump dryer at a constant drying pressure of 0.2 bars and drying temperatures ranging from 50 °C to 65 °C. The experimental results were fitted to a number of well-known thin layer drying models and it was found, for the range of drying temperature tested, that the Midilli model is the best model for all Tom Yum herbs. To account for the influence of drying temperature, the constants and coefficients of model were formulated as functions of the drying temperature. Statistical tests of agreement between the model and experimental results were performed by determining the coefficient of determination (R2) , reduced chi-square (χ2) and root mean square error (RMSE). It was found that the model is in very good agreement with the experimental results.

Thin Layer Drying Characteristics of Eriste: A Dried Cereal Product of Turkey

2008 ◽  
Vol 4 (2) ◽  
Author(s):  
Ayhan Duran ◽  
Ali Adnan Hayaloglu ◽  
Ihsan Karabulut
Keyword(s):  
Thin Layer ◽  
Air Temperature ◽  
Effective Diffusivity ◽  
Sample Thickness ◽  
Suitable Model ◽  
Sample Weight ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Cereal Product ◽  
Drying Curves

Effect of air temperature (50, 60 and 70 °C) and sample thickness (1.0, 1.4 and 1.8 mm) on the thin-layer drying characteristics of eriste was studied by using a tray dryer. The data of sample weight, dry and wet-bulb temperatures were recorded continuously during each experiment and drying curves were obtained. The drying curves were then fitted to five mathematical models available in the literature to estimate a suitable model for drying of eriste. Verma et al. model gave better predictions than other models and satisfactorily described the thin layer characteristics of eriste. The effective diffusivity varied from 1.8 x exp-10 to 1.5 x exp-9 m2 s-1 over the temperature range.

Reversing the Friday peak in metastatic cord compression referrals: Not as simple as previously thought?

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e14050-e14050
Author(s):  
Olusola Michael Adeleke ◽  
Rubyyat A Hakim ◽  
Laurence Dean ◽  
Huma Zahid ◽  
Rongyu Lin ◽  
...  
Keyword(s):  
Goodness Of Fit ◽  
Single Point ◽  
District General Hospital ◽  
Cord Compression ◽  
Radiology Reporting ◽  
Goodness Of Fit Test ◽  
Tertiary Centre ◽  
Chi Squared ◽  
Early Case ◽  
The Uk

e14050 Background: Historically, metastatic spinal cord compression (MSCC) referrals trend towards a Friday peak in incidence (Koiter E, Radioth Onc 2013). However, data from a single, tertiary centre in the UK showed a reversal in the Friday peak (Adeleke S, Annals of Oncology 2020). This was attributed to early case referrals and quicker treatment decisions. In this new study, we explored whether a similar pattern was apparent in multiple district general hospital (DGH) settings and attempt to identify underlying causes. DGHs manage a larger proportion of cancer patients in the UK. Methods: 1,069 patients between 1 Jan 2015 and 31 Dec 2020 were identified across 4 hospitals in Kent, UK with a population of 1.6 million people. 220, 181, 182, 159, 134 and 193 MSCC patients were identified annually (2015-2020). Commonest cancers were prostate (24.1%), lung (19.3%) and breast (12.3%). Thoracic and lumbar regions constituted 80% of MSCC sites. Kruskal Wallis was used to compare differences in referrals across weekdays. Data was then dichotomised to Fridays only vs. other days of the week combined, as previously reported (De Bono B, Acta Neurochir 2019). Chi squared was used to compare frequency of referrals between the two groups. Chi squared goodness of fit test was conducted to detect if Friday reflected the day with highest referrals across the week. Results: Across the region, 2015 saw the highest number of Friday referrals relative to other days, p= 0.002. Friday referrals continued to drop, year on year, until 2018 with a corresponding increase in mid-week referrals. After 2018, there was a return in trend to a further Friday peak across the region, though p= 0.836. On an individual hospital basis, the persistent Friday peak in the region was driven by two hospitals. Having a 7-day acute oncology service (AOS), 7-day radiology reporting and single referral point of contact in the department, were factors identified that kept the referrals across the week uniform. On another note, a substantial shift towards a single 8Gy fraction vs. 20Gy in 5 fractions was observed across the region. This change coincided with SCORAD III data (Hoskin P, ASCO 2017) and demonstrates adherence to evidence-based practice in the region. Conclusions: This large multi-centre retrospective study shows a differential referral pattern in the region, with hospitals with 7-day AOS/Radiology reporting and single point of referral (e.g, similar to MSCC coordinator role) having a quicker treatment turnaround and uniform referrals across the week. The MSCC coordinator has been shown to streamline service, ensure timely decision-making and improved survival outcomes (Richards L, Spine J 2017). The role is recommended by NICE UK. DGHs should consider appointing an MSCC coordinator when designing/auditing their service. The shift towards single 8Gy fraction can provide a ‘one-stop’ service where patients are scanned, planned and treated on the same day.

Edinburgh Handedness Inventory Scores: Caucasian and American Indian College Students

1994 ◽  
Vol 78 (2) ◽  
pp. 675-680 ◽  
Author(s):  
Sherry M. Dingman ◽  
Mary A. Mroczka
Keyword(s):  
College Students ◽  
American Indian ◽  
American Indians ◽  
Goodness Of Fit ◽  
Single Gene ◽  
Empirical Support ◽  
Racial Groups ◽  
Frequency Distributions ◽  
Chi Squared ◽  
American Indian College Students

Laterality Quotients for 80 American Indian college students were less right-biased than those for 80 Caucasian college students on the Edinburgh Handedness Inventory. Oldfield's 1971 empirically derived deciles for the Edinburgh Handedness Inventory were used to assign decile levels to the data. Deciles were then used to assign data to one of three proposed handedness phenotype classifications. Pheno-type classifications were based on Annett's 1985 proposed distribution for a single gene theorized to underlie human handedness. Chi-squared goodness-of-fit analysis showed that the data for Caucasian college students did not differ significantly from what would be anticipated by Annett's model, but American Indians differed significantly. Results provide empirical support for the hypothesis that frequency distributions for Annett's hypothesized right-shift gene may differ across racial groups.

scholarly journals MENENTUKAN DISTRIBUSI REPRESENTATIF FREQUENSI CURAHAN HUJAN HARIAN MAKSIMUM DENGAN METODEHISTOGRAM DAN METODE PARAMETIK DI PROVINSI SUMATERA BARAT

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Selpa Dewi
Keyword(s):  
Goodness Of Fit ◽  
Type Iii ◽  
Pearson Type ◽  
Chi Squared ◽  
Anderson Darling

Penelitian ini bertujuan untuk menentukan distribusi yang representatif frequensi curahan hujan harian maksimum di Provinsi Sumatera Barat. Data yang digunakan untuk penelitian ini diambil dari data hujan maksimum harian selama 20 sampai 40 tahunan, dengan 24 stasiun penakar hujan untuk provinsi Sumatera Barat. Data masing-masing stasiun kemudian disusun dalam dua jenis deret data, yaitu deret data annual maxima dan deret data annual exceedances. Dari hasil uji deret data ini diharapkan mengikuti satu atau beberapa dari distribusi yang umum dipakai dalam hidrologi rekayasa, yaitu distribusi normal, normal-log, Gumbel, Gama-II, Gama-III dan distribusi Log-Pearson Type III (LP-III). Dengan mengunakan uji kecocokan (goodness of fit), uji parametrik, Chi-Squared test, Kolmogorov-Smirnovtest dan Anderson-Darling test ditambah dengan metode histrogram (visual).Kata kunci:Intensitas hujan distribusi representative annual maxima, annual exceendances, goodness of fitprovinsi Sumatera Barat.

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