Resonance attenuation in fluid transmission through channels without the use of accumulator systems

2021 ◽  
pp. 1-9
Author(s):  
Prashant Unnikrishnan Nair
Keyword(s):  
High Rate ◽  
Harsh Environments ◽  
Moderate Pressure ◽  
Test Results ◽  
Hydraulic Systems ◽  
Resonance Factor ◽  
Risk Of Rupture ◽  
Resonance Test ◽  
Pressure Spike ◽  
Better Than

Abstract Accumulators are often effective in reducing noise from hydraulic systems due to their pressure spike dampening effect. Their use is feasible in most cases where replacements are easy. However, certain conditions like harsh environments or sub-sea fishing make accumulator replacements extremely difficult. In line dampeners provide a very easy solution but have never been designed to cater for the resonance dampening as such. Commercially developed inline dampeners also have nitrogen filled bladders or act like and behave as accumulators, posing the same risk of rupture and replacements. This paper addresses a simplistic approach for such channels replacing the need for a bladder/bladder-less accumulator for moderate pressure high rate flow of a non-Newtonian fluid for reduced resonance. Test results show minimal back pressure from the usage of the device. The paper only addresses the resonance factor and not the usual pressure spike control that hydraulic lines suffer from where accumulators work best. Proprietary material and innovation used in the design of the dampener is not discussed here. Sound attenuation for various input levels are compared between the device made and a traditional accumulator and test results were later used in the complete development of an inline bladder-less nitrogen free resonance attenuation device that performs better than having an accumulator in the system.

Implementasi Voip Server Berbasis IPV6 Dengan Raspberry PI

2019 ◽  
Vol 9 (01) ◽  
pp. 47-54
Author(s):  
Rabbai San Arif ◽  
Yuli Fitrisia ◽  
Agus Urip Ari Wibowo
Keyword(s):  
Internet Protocol ◽  
Wireless Transmission ◽  
Raspberry Pi ◽  
Test Results ◽  
Average Delay ◽  
Ipv6 Network ◽  
Ip Network ◽  
Selection Of ◽  
Better Than

Voice over Internet Protocol (VoIP) is a telecommunications technology that is able to pass the communication service in Internet Protocol networks so as to allow communicating between users in an IP network. However VoIP technology still has weakness in the Quality of Service (QoS). VOPI weaknesses is affected by the selection of the physical servers used. In this research, VoIP is configured on Linux operating system with Asterisk as VoIP application server and integrated on a Raspberry Pi by using wired and wireless network as the transmission medium. Because of depletion of IPv4 capacity that can be used on the network, it needs to be applied to VoIP system using the IPv6 network protocol with supports devices. The test results by using a wired transmission medium that has obtained are the average delay is 117.851 ms, jitter is 5.796 ms, packet loss is 0.38%, throughput is 962.861 kbps, 8.33% of CPU usage and 59.33% of memory usage. The analysis shows that the wired transmission media is better than the wireless transmission media and wireless-wired.

STUDY ON THRIVE SCORE IN THE PROGNOSIS OF ISCHEMIC STROKE

2017 ◽  
pp. 22-24
Author(s):  
Thi Thao Nhi Tran ◽  
Dinh Toan Nguyen
Keyword(s):  
Ischemic Stroke ◽  
Clinical Outcome ◽  
Regression Models ◽  
Cross Sectional Study ◽  
High Rate ◽  
Vascular Events ◽  
Cross Sectional ◽  
Key Words Ischemic Stroke ◽  
Outcome Mortality ◽  
Better Than

Background and Purpose: Stroke is the second cause of mortality and the leading cause of disability. Using the clinical scale to predict the outcome of the patient play an important role in clinical practice. The Totaled Health Risks in Vascular Events (THRIVE) score has shown broad utility, allowing prediction of clinical outcome and death. Methods: A cross-sectional study conducting on 102 patients with acute ischemic stroke using THRIVE score. The outcome of patient was assessed by mRankin in the day of 30 after stroke. Statistic analysis using SPSS 15.0. Results: There was 60.4% patient in the group with THRIVE score 0 – 2 points having a good outcome (mRS 0 - 2), patient group with THRIVE score 6 - 9 having a high rate of bad outcome and mortality. Having a positive correlation between THRIVE score on admission and mRankin score at the day 30 after stroke with r = 0.712. THRIVE score strongly predicts clinical outcome with ROC-AUC was 0.814 (95% CI 0.735 - 0.893, p<0.001), Se 69%, Sp 84% and the cut-off was 2. THRIVE score strongly predicts mortality with ROC-AUC was 0.856 (95% CI 0.756 - 0.956, p<0.01), Se 86%, Sp 77% and the cut-off was 3. Analysis of prognostic factors by multivariate regression models showed that THRIVE score was only independent prognostic factor for the outcome of post stroke patients. Conclusions: The THRIVE score is a simple-to-use tool to predict clinical outcome, mortality in patients with ischemic stroke. Despite its simplicity, the THRIVE score performs better than several other outcome prediction tools. Key words: Ischemic stroke, THRIVE, prognosis, outcome, mortality

Kemampuan Komunikasi Matematika: Studi Komparasi Pembelajaran Number Head Together (NHT) dan Media Power Point (PPT)

2020 ◽  
Vol 3 (1) ◽  
pp. 39-50
Author(s):  
Bernadeta Ritawati ◽  
Sri Wahyuni
Keyword(s):  
Communication Skills ◽  
Hypothesis Test ◽  
Test Results ◽  
Mathematical Communication ◽  
Cluster Technique ◽  
Significance Level ◽  
Quasi Experimental ◽  
Power Point ◽  
Media Power ◽  
Better Than

This research is a quasi-experimental study that aims to determine the comparison of students' mathematical communication abilities with the cooperative learning model of the NHT and PPT media in class VII SMP Negeri 02 Ngabang. The population in this study were all students of class VII SMP 02 Ngabang consisting of 3 classes. The sample in this study was taken by using the Random Sampling Cluster technique. Class VII A as class I experimental class with 24 students and class VII B as a experimental class II with 24 students. The instruments used were pretest and posttest in the form of description. Data analysis uses the t test with a significance level of 5%. The results showed the average posttest for the NHT class was 72.5 and the average posttest for the PP class was 66.666. From the posttest hypothesis test results obtained t hitung> t tabel (1.9522> 1,667). Because t_hitung> t_tabel, H_0 is rejected and H_a is accepted. This means that students' mathematical communication skills taught with the NHT are better than using Power point media.

Research on Quick Superplastic Forming for Aluminium Alloy Sheet

2012 ◽  
Vol 735 ◽  
pp. 301-306 ◽  
Author(s):  
Hai Jian Liang ◽  
Xiao Wei Wu ◽  
Yong Wang ◽  
Quan Lin Jin ◽  
Zhao Li Ma ◽  
...  
Keyword(s):  
Mass Production ◽  
Simulation Experiment ◽  
Hot Stamping ◽  
Superplastic Forming ◽  
Alloy Sheet ◽  
High Rate ◽  
Hot Forming ◽  
Forming Technology ◽  
Complex Process ◽  
Better Than

This article describes the high rate superplastic forming. The high rate superplastic forming technology is a new complex process,which integrates hot stamping and superplastic forming .It has feature of rapidity of the hot stamping and character of excellent formability of the superplastic forming.We obtained the best proportion of the hot forming and the superplastic forming through simulation experiment, and formed a car’s abonnet by applying the proportion.Compared with the high rate superplastic forming,the forming quality is better than that of hot forming. and the forming time is less than that of superplastic forming. Result shows that ,the high rate superplastic forming technology can meet the requirements for mass production.

scholarly journals Evaluation of the Feasibility of NaCaPO4-Blended Zirconia as a New CAD/CAM Material for Dental Restoration

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou
Keyword(s):  
Computer Aided Design ◽  
Optical Microscope ◽  
Dental Restoration ◽  
Numerical Control ◽  
Test Results ◽  
Cnc Machine ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design ◽  
Better Than

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.

Influence of Collagen Status on Microstructures of Porous Collagen/TCP Composites

2007 ◽  
Vol 330-332 ◽  
pp. 495-498
Author(s):  
Chao Zou ◽  
Wen Jian Weng ◽  
Xu Liang Deng ◽  
Kui Cheng ◽  
Pi Yi Du ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Cell Growth ◽  
Tricalcium Phosphate ◽  
Freeze Drying ◽  
Alkali Treatment ◽  
Test Results ◽  
Collagen Matrices ◽  
The Difference ◽  
Porous Composites ◽  
Better Than

Two starting collagens, sponge and floc collagen, were used to prepare collagen/tricalcium phosphate (TCP) composites. The resulting composites were porous and had 200μm pore size. However, there was a difference in the microstructure of the pore walls for the composites derived from the two collagens, the pore walls in sponge collagen/TCP composite were still porous and had 200 nm micropores size, TCP particles were trapped in collagen matrices. While floc collagen/TCP composite had smooth and dense walls in which TCP particles were embedded. The difference could be attributed to the starting collagen with different status. Sponge collagen has a soft structure, which easily becomes disassembled fibrils during alkali treatment, the disassembled fibrils are integrated again to form a dense morphology for pore walls after freeze-drying. While floc collagen has already a low disassembly degree, the alkali treatment could not be able to separate the fibrils, this remains as micropores in pore walls after freeze-drying. Both porous composites are significant in bone tissue engineering or regeneration. MTT test results showed the two composites had good cytocompatibility, and sponge collagen/TCP composite was somewhat better than floc collagen/TCP composite, which could result from that micropores derived roughness in pore walls of sponge collagen/TCP composite is suitable for cell growth.

Second Paper: Deep Drawing and Free Forming Using a Water Hammer Technique

1964 ◽  
Vol 179 (1) ◽  
pp. 222-233 ◽  
Author(s):  
A. P. Vafiadakis ◽  
W. Johnson ◽  
I. S. Donaldson
Keyword(s):  
Deep Drawing ◽  
Time History ◽  
Water Hammer ◽  
High Rate ◽  
Pressure Time ◽  
Order Of Magnitude ◽  
History Of ◽  
Overall Efficiency ◽  
Initial Movement ◽  
Better Than

Earlier work on a water-hammer technique for high-rate forming of sheet metal has been extended to include work on deep drawing using lead plugs. A study of the pressure-time history of a deforming blank during its initial movement is reported. An assessment of the overall efficiency of the process has been made and is found to be about 50 per cent; this is an order of magnitude better than that found with comparable electro-hydraulic and explosive methods.

DEVELOPMENT OF BREAD FORMULATION USING OF BARNYARD GRASS (ECHINOCHLOA FRUMENTACEA) FLOUR TO IMPROVE THE QUALITY

2019 ◽  
Author(s):  
Н.Н. ФИЛОНОВА ◽  
С.В. ЯЦЕНКО ◽  
М.К. САДЫГОВА
Keyword(s):  
Control Sample ◽  
Ash Content ◽  
High Rate ◽  
Bakery Products ◽  
Barnyard Grass ◽  
Bread Crumb ◽  
Rye Bread ◽  
Lifting Force ◽  
Echinochloa Frumentacea ◽  
Better Than

Оптимизирована рецептура хлеба «Паляница украинская» путем введения 15% пайзовой муки (ПМ) и 5% льняной муки (ЛМ) взамен части пшеничной. Образец с добавкой 15% ПМ и 5% ЛМ имел достаточно высокий показатель бродильной активности и самый высокий показатель подъемной силы – 28 мин в отличие от образца с тем же количеством ПМ, но без добавки ЛМ (43,3 мин) и контрольного образца без добавок (45,5 мин). Добавка в рецептуру хлеба ПМ увеличила в нем содержание белка на 14,68%, золы – более чем в 2 раза. Добавление ЛМ нейтрализовало специфические аромат и вкус пайзы, повлияло на формоудерживающую способность полуфабриката: во время выпечки изделие не расплывалось, выпеченный хлеб имел эластичный пропеченный мякиш с равномерной пористостью, на корке отсутствовали трещины и подрывы. В результате добавки ПМ и ЛМ опытный образец приобрел насыщенный цвет корки и мякиша, приятный аромат, напоминающий аромат ржаного хлеба. Образец хлеба, содержащий 15% ПМ и 5% ЛМ, по истечении 72 ч хранения имел наименьший показатель крошковатости – 3,59% к массе мякиша хлеба и самый высокий показатель набухаемости – 154,5%, лучше других образцов сохранил потребительские качества: вкус и аромат изделия практически не изменились, мягкость мякиша снизилась незначительно. Внесение ПМ взамен части пшеничной в рецептуру хлеба способствует увеличению продолжительности срока хранения изделия, что позволяет рекомендовать использование пайзовой муки в производстве хлебобулочных изделий. The formulation of bread «Palyanitsa ukrainskaya» is optimized by introducing 15% of barnyard grass flour (GF) and 5% of flax flour (FF) instead of wheat flour. The sample with the addition of 15% of GF and 5% of FF had a sufficiently high rate of fermentation activity and the highest rate of lifting force – 28 min in contrast to the sample with the same amount of GF, but without the addition of FF (43,3 min) and the control sample without additives (45,5 min). Additive in bread formulation GF increased its protein content by 14,68%, ash content – more than 2 times. The addition of FF neutralized the specific flavor and taste of the barnyard grass, influenced the form-holding ability of the semi-finished product: during baking the product was not blurred, the baked bread had an elastic baked crumb with uniform porosity, cracks and explosions were absent on the crust. As a result of the addition of GF and FF the prototype acquired a rich color of crust and crumb, a pleasant aroma reminiscent of rye bread. A sample of bread containing 15% GF and 5% FF after 72 h of storage had the lowest crumbiness index – 3,59% by weight of bread crumb and the highest rate of swelling – 154,5%, better than other samples retained consumer qualities: taste and aroma of the product has not changed, the softness of the crumb decreased slightly. Introduction of GF instead of part wheat in the bread formulation helps to increase the duration of the shelf life of the product, which allows us to recommend the use of barnyard grass flour in production of bakery products.

Durability of BFRP and Hybrid FRP Sheets under Freeze-Thaw Cycling

2010 ◽  
Vol 163-167 ◽  
pp. 3297-3300 ◽  
Author(s):  
Jia Wei Shi ◽  
Hong Zhu ◽  
Zhi Shen Wu ◽  
Gang Wu
Keyword(s):  
Mechanical Properties ◽  
Test Data ◽  
Mechanical Characteristics ◽  
Test Results ◽  
Freeze Thaw ◽  
Frp Composites ◽  
Test Parameters ◽  
The Stability ◽  
Better Than

Coupon tests were conducted to investigate the mechanical characteristics of basalt FRP (BFRP) sheet, basalt-carbon hybrid FRP sheets and the corresponding epoxy rein under the effect of freeze-thaw cycling. FRP sheets and epoxy rein coupons were subjected to up to 200 and 250 freeze-thaw cycles respectively. Test parameters included the number of freeze-thaw cycles and the types of FRP composites. Test results show that (1) BFRP sheet perform better than CFRP or GFRP sheets under high freeze-thaw cycles; (2) exposed hybrid FRP sheets not only show very little loss in mechanical properties, but also contribute to the stability of test data; (3) mechanical properties of rein epoxy decrease significantly with increasing freeze-thaw cycles.

scholarly journals Development of Learning Tools by Application of Problem Based Learning Models to Improve Mathematical Communication Capabilities of Sequence and Series Materials

2020 ◽  
Vol 4 (1) ◽  
pp. 62
Author(s):  
Nur Atika ◽  
Yenita Roza ◽  
Atma Murni
Keyword(s):  
Communication Skills ◽  
Problem Based Learning ◽  
Development Research ◽  
Learning Tools ◽  
Test Results ◽  
Design Development ◽  
Learning Models ◽  
Mathematical Communication ◽  
Analysis Design ◽  
Better Than

This research was motivated by the lack of learning tools that can improve students' Mathematical Communication Skills (KKM). Activities that can encourage students to improve KKM have not been designed by the teacher in the learning device properly. This study aims to produce learning tools by applying Problem Based Learning models to improve KKM. This development research used the ADDIE development model with the stages of Analysis, Design, Development, Implementation, and Evaluation. The results of Syllabus, RPP, LKPD and KKM validation results showed highly valid criteria with percentages of 91.67%, 91.30%, 89.09%, and 87.15%, respectively. Practicality results indicate a very practical criterion with the percentage of small group trials at 95.57%, large group trials at 96.07%, and teacher responses at 96.25%. The effectiveness test results state that KKM of students who use learning tools with PBL models is better than KKM of students who use conventional learning.

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