scholarly journals Influence of production systems on the properties of fresh and hardened shotcrete

2018 ◽  
Vol 18 (2) ◽  
pp. 71-86
Author(s):  
Gabriela Cechin ◽  
Carina Mariane Stolz ◽  
Ângela Borges Masuero
Keyword(s):  
Flexural Strength ◽  
Analysis Of Variance ◽  
Water Retention ◽  
Production Systems ◽  
Rotation Speed ◽  
Mixing Time ◽  
Mixing Process ◽  
Significant Difference ◽  
Flow Table ◽  
Table Index

Abstract In modern shotcrete operations, the mixing and pumping steps are carried out using different production systems and equipment. This adds an element of uncertainty to the process because of variables such as mixer type, rotation speed, mixing time, etc. As a result, this may result in changes to the characteristics and properties of both fresh and hardened sprayed mortar and may ultimately impair the performance of the rendering material. This study assesses the influence of production systems, particularly the mixing process, on the properties of fresh and hardened sprayed mortar. The methods used comprehend the collection and testing of mortar samples produced in wet-mix and dry-mix shotcrete systems, as well as a pre-packaged mortar batched and mixed in a laboratory mixer under controlled conditions according to the manufacturer’s instructions. Results were processed using analysis of variance (ANOVA) and multiple comparison of means using Fisher’s method. A statistically significant difference was observed in the flow table index, water retention, flexural strength and capillarity coefficient of the mortars produced using wet- and dry-mix systems.

STUDY ON PHYSICAL AND SENSORICAL CHARACTERISTICS OF FLESH RESTRUCTURED WITH SAGO CATFISH JERKY

2014 ◽  
Vol 4 (2) ◽  
pp. 55-64
Author(s):  
Amir Jayani ◽  
Zulman Efendi ◽  
Devi Silsia
Keyword(s):  
Physical Properties ◽  
Water Content ◽  
Analysis Of Variance ◽  
Test Data ◽  
Organoleptic Test ◽  
Significant Difference

This study aims to gain influence the thickness and concentration variations affect the characteristics of sago binder physical properties of catfish jerky. As well as getting influence the thickness and concentration variations affect the level of binder sago joy panelists in terms of organoleptic test. Data were analyzed by analysis of variance using the Analysis Of Variance (ANOVA). If there is a significant difference followed by a further test of DMRT 5% level (physical properties). While the hedonic test performed using Kruskal Wallis analysis. Results uniformity analysis (ANOVA) showed catfish fillet thickness and concentration of sago affect the physical properties of the water content and the level of violence. Where catfish jerky using sago binder 5% and 10% significantly different. The use of sago binder 5% and 10% led to an increase in water content. Besides the addition of the binder resulted in increasing levels of violence catfish jerky. Based on the statistics found that the influence of the thickness and concentration of the binder sago aroma, flavor and color of the sixth jerky catfish were not significantly different. But the texture was significantly different.

scholarly journals Comparison of Mechanical Properties of PMMA Disks for Digitally Designed Dentures

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1745
Author(s):  
Tamaki Hada ◽  
Manabu Kanazawa ◽  
Maiko Iwaki ◽  
Awutsadaporn Katheng ◽  
Shunsuke Minakuchi
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Water Sorption ◽  
Water Solubility ◽  
Flexural Modulus ◽  
Manufacturing Method ◽  
Heat Curing ◽  
Significant Difference ◽  
Cad Cam ◽  
Curing Method

In this study, the physical properties of a custom block manufactured using a self-polymerizing resin (Custom-block), the commercially available CAD/CAM PMMA disk (PMMA-disk), and a heat-polymerizing resin (Conventional PMMA) were evaluated via three different tests. The Custom-block was polymerized by pouring the self-polymerizing resin into a special tray, and Conventional PMMA was polymerized with a heat-curing method, according to the manufacturer’s recommended procedure. The specimens of each group were subjected to three-point bending, water sorption and solubility, and staining tests. The results showed that the materials met the requirements of the ISO standards in all tests, except for the staining tests. The highest flexural strength was exhibited by the PMMA-disk, followed by the Custom-block and the Conventional PMMA, and a significant difference was observed in the flexural strengths of all the materials (p < 0.001). The Custom-block showed a significantly higher flexural modulus and water solubility. The water sorption and discoloration of the Custom-block were significantly higher than those of the PMMA-disk, but not significantly different from those of the Conventional PMMA. In conclusion, the mechanical properties of the three materials differed depending on the manufacturing method, which considerably affected their flexural strength, flexural modulus, water sorption and solubility, and discoloration.

Study of friction stir spot welding for thermotolerant engineering thermoplastic polyimide joints

2021 ◽  
pp. 095440542199561
Author(s):  
Jicheng Gao ◽  
Jiachen Dong ◽  
Sunyi Zhang ◽  
Liang Yu ◽  
Huiming Jin ◽  
...  
Keyword(s):  
Shear Strength ◽  
Spot Welding ◽  
Dwell Time ◽  
Rotation Speed ◽  
Mixing Time ◽  
Friction Stir Spot Welding ◽  
Scanning Calorimetry ◽  
Friction Stir ◽  
Base Materials ◽  
Engineering Plastics

In this research, thermoplastic polyimide (TPI) were welding via friction stir spot welding (FSSW) in order to evaluate the feasibility of the technology. The welding tool with a tri-flute pin was used for keeping the welding effectiveness. The effect of the rotation speed and dwell time on the microstructure and shear strength was studied. The results shows that the number of gap defects between the shoulder affect zone and the pin affect zone decreased with the increase of the rotation speed. The boundary of the shoulder affect zone and the pin affect zone was no clear when increasing the dwell time from 10 s to 20 s. Long dwell time could increase the mixing time and reduce the materials viscosity, which made the structure was denser. The maximal shear strength was obtained 85.5% of the base materials. The differential scanning calorimetry (DSC) results indicated that the melting behaviour of different regions was no obvious difference. It indicated that FSSW had a feasible and potential technology to join the high temperature resistant engineering plastics.

Comparison of Prevalence, Antimicrobial Resistance, and Occurrence of Multidrug-Resistant Salmonella in Antimicrobial-Free and Conventional Pig Production

2006 ◽  
Vol 69 (4) ◽  
pp. 743-748 ◽  
Author(s):  
WONDWOSSEN A. GEBREYES ◽  
SIDDHARTHA THAKUR ◽  
W. E. MORGAN MORROW
Keyword(s):  
Antimicrobial Resistance ◽  
Production Systems ◽  
Multidrug Resistant ◽  
Resistance Pattern ◽  
Swine Production ◽  
Significant Difference ◽  
Conventional Farms ◽  
Resistance Patterns ◽  
Conventional Systems ◽  
On Farm

Conventional swine production evolved to routinely use antimicrobials, and common occurrence of antimicrobial-resistant Salmonella has been reported. There is a paucity of information on the antimicrobial resistance of Salmonella in swine production in the absence of antimicrobial selective pressure. Therefore, we compared the prevalence and antimicrobial resistance of Salmonella isolated from antimicrobial-free and conventional production systems. A total of 889 pigs and 743 carcasses were sampled in the study. Salmonella prevalence was significantly higher among the antimicrobial-free systems (15.2%) than the conventional systems (4.2%) (odds ratio [OR] = 4.23; P &lt; 0.05). Antimicrobial resistance was detected against 10 of the 12 antimicrobials tested. The highest frequency of resistance was found against tetracycline (80%), followed by streptomycin (43.4%) and sulfamethoxazole (36%). Frequency of resistance to most classes of antimicrobials (except tetracycline) was significantly higher among conventional farms than antimicrobial-free farms, with ORs ranging from 2.84 for chloramphenicol to 23.22 for kanamycin at the on-farm level. A total of 28 antimicrobial resistance patterns were detected. A resistance pattern with streptomycin, sulfamethoxazole, and tetracycline (n = 130) was the most common multidrug resistance pattern. There was no significant difference in the proportion of isolates with this pattern between the conventional (19.5%) and the antimicrobial-free systems (18%) (OR = 1.8; P &gt; 0.05). A pentaresistance pattern with ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline was strongly associated with antimicrobial-free groups (OR = 5.4; P = 0.01). While showing the higher likelihood of finding antimicrobial resistance among conventional herds, this study also implies that specific multidrug-resistant strains may occur on antimicrobial-free farms. A longitudinal study with a representative sample size is needed to reach more conclusive results of the associations detected in this study.

Evaluation of Mechanical Properties of Dental Feldsphatic Porcelains for Metal and Zirconia Core

2012 ◽  
Vol 727-728 ◽  
pp. 1104-1107
Author(s):  
Antonio Alves de Almeida-Junior ◽  
Gelson Luis Adabo ◽  
Beatriz Regalado Galvão ◽  
Diogo Longhini ◽  
Claudinei dos Santos
Keyword(s):  
Fracture Toughness ◽  
Flexural Strength ◽  
Vickers Hardness ◽  
High Hardness ◽  
Hardness Test ◽  
Dental Prostheses ◽  
Significant Incidence ◽  
Significant Difference ◽  
Fixed Dental Prostheses ◽  
Intermediate Value

Studies has been reported a significant incidence of chipping of the feldspathic porcelain veneer in zirconia-based restorations. The purpose of this study was to compare the three-point flexural strength (MPa), Weibull parameters, Vickers hardness (VHN) and Vickers indentation fracture toughness (MPa/mm1/2) in feldspatic porcelains for metal and for zirconia frameworks. Bar specimens were made with the porcelains e.MaxCeram (EM) and VitaVM9 (V9) for zirconia core, and Duceragold (DG) and VitaVMK95 (VK) for metal core (n= 15). Kruskal-Wallis and Dun test were used for statistical analysis. There was no significant difference (p=0.31) among the porcelains in the flexural strength (Median= 73.2; 74.6; 74.5; 74.4). Weibull calculation presented highest reliability for VK (10.8) followed by EM (7.1), V9 (5.7) and DG (5.6). Vickers hardness test showed that EM (536.3), V9 (579.9) and VK (522.1) had no difference and DG (489.6) had the lowest value (p.001). The highest fracture toughness was to VK (1.77), DG (1.58) had an intermediate value while V9 (1.33) and EM (1.18) had the lowest values (p.001). Despite of the suitable flexural strength, reliability and high hardness, the porcelains used to zirconia-based fixed dental prostheses showed lower fracture toughness values.

Επίδραση αναλόγου της προστακυκλίνης στην επούλωση αναστομώσεων του παχέος εντέρου επίμυων σε συνθήκες αποφρακτικού ειλεού

2012 ◽  
Author(s):  
Γεώργιος Γαλανόπουλος
Keyword(s):  
Analysis Of Variance ◽  
Anova Analysis ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Significant Difference ◽  
Fisher’S Exact Test

Στόχος της παρούσας διδακτορικής διατριβής ήταν η πειραματική μελέτη της επίδρασης της ιλοπρόστης (ανάλογο της προστακυκλίνης) στην επούλωση αναστομώσεων του παχέος εντέρου επίμυων σε συνθήκες αποφρακτικού ειλεού. Για τη μελέτη χρησιμοποιήθηκαν 80 άρρενες επίμυες, οι οποίοι χωρίστηκαν τυχαιοποιημένα σε 4 (1, 2, 3, 4) ομάδες, με 2 (α, β) ισοδύναμες υποομάδες έκαστη. Στην ομάδα 1 (ελέγχου) και 3 (ιλοπρόστη) διενεργήθηκε τμηματική εντερεκτομή και τελικοτελική αναστόμωση. Στην ομάδα 2 (ειλεός) και 4 (ειλεός και ιλοπρόστη) επιτεύχθηκαν αρχικά συνθήκες αποφρακτικού ειλεού και 24 ώρες μετά διενεργήθηκε τμηματική εντερεκτομή και τελικοτελική αναστόμωση. Η ιλοπρόστη χορηγήθηκε στις ομάδες 3 και 4 σε δόση 2μg/kg Β.Σ. σε 3ml διαλύματος NaCl 0,9% ενδοπεριτοναϊκά, διεγχειρητικά και κάθε ημέρα μέχρι τη θυσία, ενώ αντίστοιχα στις ομάδες 1 και 2 στα πειραματόζωα χορηγούνταν 3ml διαλύματος NaCl 0,9%. Σε κάθε ομάδα τα μισά πειραματόζωα (υποομάδα 1α, 2α, 3α, 4α) θυσιάστηκαν την 4η μετεγχειρητική ημέρα και τα υπόλοιπα (υποομάδα 1β, 2β, 3β, 4β) την 8η. Κατά τη νεκροτομή γινόταν μακροσκοπικός έλεγχος για ρήξη της αναστόμωσης, ύπαρξη περιτονίτιδος ή περιαναστομωτικού αποστήματος καθώς και ποσοτική αξιολόγηση των συμφύσεων σύμφωνα με την κλίμακα Van der Hamm. Ακολουθούσε μέτρηση της πίεσης διάσπασης και στη συνέχεια τμήμα της αναστόμωσης αποστέλλονταν για ιστολογική εξέταση κατά την οποία αξιολογούνταν η φλεγμονώδης αντίδραση (διήθηση από ουδετερόφιλα), η νεοαγγειογένεση, ο αριθμός των ινοβλαστών και η εναπόθεση νεοκολλαγόνου. Η ταξινόμηση των μικροσκοπικών ευρημάτων έγινε σύμφωνα με την κλίμακα Ehrlich και Hunt με τις τροποποιήσεις κατά Phillips. Επιπλέον, προσδιορίστηκε βιοχημικά η συγκέντρωση υδροξυπρολίνης και κολλαγενάσης I επί της αναστόμωσης. Για την συνοπτική παρουσίαση των αποτελεσμάτων υπολογίστηκαν απόλυτες και σχετικές συχνότητες (ποσοστά %), δείκτες κεντρικής τάσης (μέσοι όροι, διάμεσες τιμές) και δείκτες διασποράς (ελάχιστες τιμές, μέγιστες τιμές, τυπικές αποκλίσεις). Για τη σύγκριση των μέσων όρων χρησιμοποιήθηκε το κριτήριο της Ελάχιστης Σημαντικής Διαφοράς (Least Significant Difference-LSD), μετά από την εφαρμογή της μεθόδου ANOVA (Analysis of Variance). Για τις συγκρίσεις των ποσοστών, εφαρμόστηκε ο ακριβής έλεγχος του Fisher (Fisher’s Exact Test). Από την ανάλυση των πειραματικών δεδομένων προέκυψε ότι η ενδοπεριτοναϊκή χορήγηση ιλοπρόστης σε συνθήκες αποφρακτικού ειλεού, έχει ως αποτέλεσμα τον περιορισμό της αρνητικής δράσης του ειλεού στην επούλωση των αναστομώσεων του παχέος εντέρου. Συγκεκριμένα, την 4η και 8η μετεγχειρητική ημέρα ελαττώνει σημαντικά την απώλεια σωματικού βάρους. Επίσης, προάγει τη νεοαγγειογένεση, ενώ συγχρόνως αυξάνει τον πολλαπλασιασμό των ινοβλαστών και τη συγκέντρωση υδροξυπρολίνης. Επιπλέον, την 4η μετεγχειρητική ημέρα ελαττώνει τη φλεγμονώδη αντίδραση και μειώνει τη συγκέντρωση κολλαγενάσης Ι. Σταδιακά, την 8η μετεγχειρητική ημέρα αυξάνει τη σύνθεση νεοκολλαγόνου στην περιοχή της αναστόμωσης. Οι παραπάνω δράσεις έχουν ως αποτέλεσμα την αύξηση της μηχανικής ισχύος των αναστομώσεων, κατά την 4η και 8η μετεγχειρητική ημέρα, όπως αυτή προκύπτει από τη μέτρηση των πιέσεων διάσπασης. Συμπερασματικά, η άμεση μετεγχειρητική ενδοπεριτοναϊκή χορήγηση ιλοπρόστης ενισχύει τους μηχανισμούς επούλωσης και αντισταθμίζει την αρνητική δράση του ειλεού στην επούλωση των αναστομώσεων του παχέος εντέρου.

Retention of Bilateral Performance as a Function of Practice Order

1978 ◽  
Vol 46 (1) ◽  
pp. 43-46 ◽  
Author(s):  
Paul Dunham
Keyword(s):  
Analysis Of Variance ◽  
Repeated Measures ◽  
Rotation Speed ◽  
Sequential Order ◽  
Rotary Pursuit

The purpose of this study was to investigate the effect of practice order and initial performance hand on the bilateral retention of a simple tracking skill for 44 undergraduate volunteers. The apparatus was a Lafayette Model 30014 photoelectric rotary pursuit. The circle template was employed with rotation speed set at 20 rpm. Subjects were given 20-sec. trials and required to reach a criterion of 70% time on target twice in succession with both hands. For original practice, subjects were randomly assigned to one of four practice groups: preferred serial, non-preferred serial, preferred sequence and non-preferred sequence. Subjects' performance was recorded as the number of trials required to achieve criterion for both hands. One month later subjects were retested and scored in the same manner. A 2 × 2 × 2 analysis of variance with repeated measures on the last factor was used to determine the effects of initial hand, order of practice, testing periods, and the appropriate interactions. The results indicated that subjects' performance for the two testing periods differed significantly; retest was superior. Order of practice was significant and the sequential order more efficient during both learning and retest.

scholarly journals RESPON DOSIS PUPUK KANDANG KAMBING TERHADAP PERTUMBUHAN DAN HASIL TANAMAN MENTIMUN (Cucumis sativus L.) VARIETAS HIBRIDA

2018 ◽  
Vol 10 (2) ◽  
pp. 11-29
Author(s):  
Wahyu Wardiana Dewi
Keyword(s):  
Plant Height ◽  
Cucumis Sativus ◽  
Analysis Of Variance ◽  
Fruit Weight ◽  
Growth And Yield ◽  
Leaf Number ◽  
Cucumis Sativus L ◽  
Fruit Length ◽  
Significant Difference ◽  
Goat Manure

This research is aimet to known the responsed of cucumber plant (Cucumis sativus L.), the good means for the growth and yield of cucumber (Cucumis sativus L) of the hybrid varieties doses of good means. This study uses a randomized block design (RAK) with one factor and 5 replications. The main factors, namely: goat manure. First repeat that: without fertilizer (P0), manure goat 10 ton / ha (P1), manure goat 20 ton / ha (P2), manure goat 30 ton / ha (P3), and the latter is manure goat 40 ton / ha (P4). The parameters observed were plant height, leaf number, fruit weight, fruit length and diameter of the fruit. Data analysis by using analysis of variance (ANOVA), if the effect followed by Least Significant Difference Test (BNT). The results based on the analysis of variance showed that: 1) Treatment of manure goat (P) significantly affected the growth and yield of cucumber plants include all the parameters of observation starting plant height, leaf number, fruit weight, fruit length and fruit diameter. Dose goat manure 40 t / ha is the best concentration to produce the highest average values for all parameters. The lowest value of all parameters are shown on the dose P0 (without manure goat / control).

scholarly journals Fuel and lubricant consumption in felling the young oak-hornbeam stands

2002 ◽  
pp. 59-66
Author(s):  
Vojislav Bajic ◽  
Milorad Danilovic
Keyword(s):  
Statistical Analysis ◽  
Analysis Of Variance ◽  
Unit Area ◽  
Function Form ◽  
Tree Diameter ◽  
Significant Difference ◽  
The Difference ◽  
Level Of Significance ◽  
Average Consumption

Based on the elements of statistical analysis on the dependence of fuel and lubricant consumption on tree diameter, it was assessed that with the increase of tree diameter, the fuel and lubricant consumption in the young oak and hornbeam stands decreases significantly, both in clear felling and in thinning and that the function form Y=exp(a+b x X?1) is the best description of the correlation The consumption of fuel compared to lubricant consumption is almost double, which agrees with the results of the previous studies. Average consumption of fuel and lubricant is 17.43 mL x tree?1, on the plots 20.27 mL x tree?1, average consumption of lubricant per tree on skid roads is 9.4 mL x tree?1, on the plots 11 mL x tree?1. The higher consumption of fuel and lubricant on the plots with selective thinning is the consequence of the longer time needed for the conversion per tree, compared to that in clear felling The consumption of fuel per unit area on the skid roads (clear felling) is 22.9 L x ha?1, on the plots (selective thinning) 7.6 L x ha?1. The consumption of lubricant on the skid roads is 13.3 L x ha?1, on the plots 4.29 L x ha?1. The higher consumption of fuel and lubricant per unit area on the skid roads is due to the difference in the number of trees per unit area Based on the results of the analysis of variance, it was found out that between fuel and lubricant consumption in selective thinning and in felling the trees along tractor skid roads there is no statistically significant difference at the level of significance of 95%. So, for practical purposes, the unique norms of consumption can be established for the stands similar to those in which the study was performed.

scholarly journals PENGARUH KONSENTRASI STARTER BAKTERI Lactobacillus plantarum TERHADAP BEBERAPA KOMPONEN MUTU TEPUNG PORANG (Amorphophallus oncophyllus)

Pro Food ◽  
2021 ◽  
Vol 6 (2) ◽  
pp. 673
Author(s):  
Ade Irma Juliana ◽  
Moegiratul Amaro ◽  
Nazaruddin Nazaruddin
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Protein Content ◽  
Lactobacillus Plantarum ◽  
Analysis Of Variance ◽  
Ph Value ◽  
Significance Level ◽  
Randomized Design ◽  
Significant Difference ◽  
Polynomial Orthogonal

ABSTRACT               This study aims to determine the effect of Lactobacillus plantarum bacterial starter concentration on some quality of the porang flour. This study used experimental design one-factor Completely Randomized Design (CRD) consisted of BAL concentration (KB) of Lactobacillus plantarum with 6 treatments which is 0%, 5%, 10%, 15%, 20% and 25%. Each of treatment were repeated three times to obtain 18 unit samples. Data from observations were analyzed using analysis of variance (Analysis of Variance) at 5% significance level using Co-stat software. If there are significant differences, a further Polynomial Orthogonal and Honestly Significant Difference (BNJ) test is performed at a level of 5%. The parameters observed included pH value, protein content, water content, yield, total lactic acid bacteria, organoleptic parameters of color and aroma (hedonic and scoring). The results showed that the concentration of Lactobacillus plantarum bacterial 20% was the best treatment in producing porang flour, pH value 5.72, protein content 6.49%, yield 9.33%, total lactic acid bacteria 6.66 log CFU / g and color rather brown and slightly acidic aroma and somewhat preferred by panelists. Keywords: Porang flour, starter concentration, Lactobacillus plantarum   ABSTRAK             Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi starter bakteri Lactobacillus plantarum terhadap beberapa komponen mutu tepung porang. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan satu faktor yakni konsentrasi BAL (KB) jenis Lactobacillus plantarum dengan 6 perlakuan yaitu 0%, 5%, 10%, 15%, 20% dan 25%. Masing-masing perlakuan diulang sebanyak 3 kali sehingga diperoleh 18 unit percobaan. Data hasil pengamatan dianalisis menggunakan analisis keragaman (Analysis of Variance) pada taraf nyata 5% menggunakan software Co-stat. Apabila terdaapat beda nyata, dilakukan uji lanjut Polynomial Orthogonal dan Beda Nyata Jujur (BNJ) pada taraf 5%. Adapun parameter yang diamati meliputi nilai pH, kadar protein, kadar air, rendemen, total bakteri asam laktat, parameter organoleptik warna dan aroma (hedonik dan scoring). Hasil penelitian menunjukkan bahwa konsentrasi strater bakteri Lactobacillus plantarum 20% merupakan perlakuan terbaik dalam menghasilkan tepung porang nilai pH 5,72, kadar protein 6,49%, rendemen 9,33%, total bakteri asam laktat 6,66 log CFU/g serta warna agak coklat dan aroma agak asam serta agak disukai panelis.    Kata Kunci: Tepung porang, konsentrasi starter, Lactobacillus plantarum

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