Experimental Research on the Mechanical Parameters of Frozen Pipes under Low Temperature

2011 ◽  
Vol 194-196 ◽  
pp. 895-898 ◽  
Author(s):  
Dong Wei Li ◽  
Hai Yan Liu ◽  
Ju Hong Fan ◽  
Ren He Wang ◽  
Bi Juan Luo
Keyword(s):  
Low Temperature ◽  
Mechanical Parameters ◽  
Test Results ◽  
Brittle Transition ◽  
Axial Tensile ◽  
Different Temperatures ◽  
Bending Capacity ◽  
And Performance ◽  
Overall Bending ◽  
Selection Of

We carried out experiments of the mechanical properties of frozen pipes under different temperatures (-5°C, -10°C, -15°C), obtained axial tensile stress - strain curves of the steel and performance of the overall bending under low temperature conditions. The results showed that: the freezing pipes bending capacity increased with the decrease of temperature, but the stiffness was decreased with the decreasing temperature; the steel yield strength and ultimate strength were both increased with the decrease of temperature, the elongation and sectional shrinkage were decreased with the decrease of temperature. The test results provided the basis for the further research of frozen pipes’ ductile-brittle transition, fracture and other acts in low temperature, and provided reference for the selection of frozen pipe and engineering design.

scholarly journals Derivation and Performance of Standardized Enhanced Liver Fibrosis (ELF) Test Thresholds for the Detection and Prognosis of Liver Fibrosis

2019 ◽  
Vol 3 (5) ◽  
pp. 815-826 ◽  
Author(s):  
James Day ◽  
Preya Patel ◽  
Julie Parkes ◽  
William Rosenberg
Keyword(s):  
Liver Fibrosis ◽  
Delphi Panel ◽  
Test Results ◽  
Hazard Ratios ◽  
Test Thresholds ◽  
And Performance ◽  
Using Data ◽  
Relationship Of ◽  
The Relationship ◽  
Selection Of

Abstract Introduction Noninvasive tests are increasingly used to assess liver fibrosis and determine prognosis but suggested test thresholds vary. We describe the selection of standardized thresholds for the Enhanced Liver Fibrosis (ELF) test for the detection of liver fibrosis and for prognostication in chronic liver disease. Methods A Delphi method was used to identify thresholds for the ELF test to predict histological liver fibrosis stages, including cirrhosis, using data derived from 921 patients in the EUROGOLF cohort. These thresholds were then used to determine the prognostic performance of ELF in a subset of 457 patients followed for a mean of 5 years. Results The Delphi panel selected sensitivity of 85% for the detection of fibrosis and >95% specificity for cirrhosis. The corresponding thresholds were 7.7, 9.8, and 11.3. Eighty-five percent of patients with mild or worse fibrosis had an ELF score ≥7.7. The sensitivity for cirrhosis of ELF ≥9.8 was 76%. ELF ≥11.3 was 97% specific for cirrhosis. ELF scores show a near-linear relationship with Ishak fibrosis stages. Relative to the <7.7 group, the hazard ratios for a liver-related outcome at 5 years were 21.00 (95% CI, 2.68–164.65) and 71.04 (95% CI, 9.4–536.7) in the 9.8 to <11.3 and ≥11.3 subgroups, respectively. Conclusion The selection of standard thresholds for detection and prognosis of liver fibrosis is described and their performance reported. These thresholds should prove useful in both interpreting and explaining test results and when considering the relationship of ELF score to Ishak stage in the context of monitoring.

scholarly journals Effects of brassinosteroids and gibberellin on water uptake and performance of soya bean seeds under different temperatures

2021 ◽  
Vol 49 (2) ◽  
pp. 141-157
Author(s):  
Kantima Thongsri ◽  
Kanokwan Teingtham ◽  
Juangjun Duangpatra ◽  
Jutamas Romkaew
Keyword(s):  
Seed Germination ◽  
Low Temperature ◽  
Seed Treatment ◽  
Soya Bean ◽  
Bean Seed ◽  
Negative Effects ◽  
Seed Imbibition ◽  
Different Temperatures ◽  
Mean Germination Time ◽  
And Performance

Low temperature has negative effects on seed performance and seedling growth in soya bean, reducing stand establishment. It was hypothesised, that seed treatment with plant hormones could improve seed imbibition and performance at low temperature. Therefore, the effects of 24-epibrassinolide (EBL) and gibberellic acid (GA3) on soya bean seed germination were studied. Seeds of 'CM60' and 'CM0701-24' were imbibed with 0.25 or 0.50 ppm EBL, 50 or 100 ppm GA3, or distilled water at 10, 15, 20 and 25°C. The seed imbibition patterns of the two soya bean varieties followed a similar trend. Low temperature delayed seed imbibition resulting in longer time to reach the end of phases 1 and 2 of seed germination as compared with high temperature. Soya bean seeds treated with 50 or 100 ppm GA3 showed increased germination index, shoot and root length and reduced mean germination time. Thus, 50-100 ppm GA3 could be used as a pre-soaking seed treatment to improve soya bean seed and seedling performance under low temperature.

Quantifying Bolt Relaxation During High Temperature Operation

2017 ◽  
Author(s):  
Warren Brown ◽  
Tze-Yew Lim
Keyword(s):  
Preliminary Test ◽  
Bolted Joints ◽  
Yield Limit ◽  
Test Results ◽  
Different Temperatures ◽  
High Level ◽  
High Temperature Operation ◽  
Very High ◽  
Major Consideration ◽  
Selection Of

This paper presents a summary of recent testing into bolt relaxation, which occurs at temperatures above 230°C (450°F). Bolt relaxation is problematic for pressure boundary bolted joints as it can lead to joint leakage in the longer term. In addition, it should be a major consideration at the design phase, with selection of the appropriate bolt material limited not by the creep or yield limit of the material, but by the point where bolt relaxation becomes significant. Preliminary test results for different bolt materials at different temperatures are presented in this paper. The test results allow for some very high level observations regarding the acceptable design limits for different bolt and nut material combinations.

Experimental Study on the Flexural Property of GFRP I-Beam

2012 ◽  
Vol 594-597 ◽  
pp. 757-760
Author(s):  
Jin Yang Zheng ◽  
Guang You Zhang ◽  
Yun He Chen ◽  
Shi Zhen Li
Keyword(s):  
Failure Modes ◽  
Local Buckling ◽  
Fiber Reinforced Polymer ◽  
Flexural Property ◽  
Test Results ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Bending Capacity ◽  
Integral Structure ◽  
Overall Bending

The glass fiber reinforced polymer (GFRP) I-beams were tested under the third-point static loading. The load, mid-span deflection and failure modes were recorded during the flexural test. The flexural property was analyzed. The test results indicate that local buckling result in failure of integral structure. The local stability of flange plate is one of the main factors that affect the overall bending capacity of GFRP I-beams. Local strengthening should be adopted in the flange-web joint.

Selection of Anticorrosion Adhesive Layer for Steel Deck

2013 ◽  
Vol 361-363 ◽  
pp. 1137-1143
Author(s):  
Chun Xia Yan ◽  
Zhi Guo Li ◽  
Bo Su
Keyword(s):  
Steel Plate ◽  
Adhesive Layer ◽  
Adhesive System ◽  
Adhesive Force ◽  
Test Results ◽  
Different Temperatures ◽  
Adhesion Performance ◽  
Steel Deck ◽  
Selection Of ◽  
Better Than

In order to solve the problems of the pavement delamination or slip caused by the failures of waterproof adhesive layer or anti-corrosion coating, the epoxy zinc-rich paint, the epoxy clear water paint and epoxy asphalt adhesive material with good performance was selected for the roughness-adhesive force test, tensile test under different temperatures and corrosion resistance test. The optimal anti-corrosion layer and adhesive layer were selected to increase the service life of the steel deck pavement. The test results show that: When the steel roughness is 60μm, the anti-corrosion material has the highest adhesive strength with the steel plate. Both the epoxy zinc-rich paint and the epoxy water paint have high adhesive strengths with the steel plate at room temperature. But at low temperature, the adhesion performance of the epoxy water paint is significantly better than that of the epoxy zinc-rich paint. At 70 °C, the adhesive strengths of both the epoxy water paint and epoxy zinc-rich paint adhesive system greatly decrease. The destruction morphology shows the opening of the adhesive layer. The specialized anti-corrosion coating must be brushed on the steel deck.

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.

PENGEMBANGAN BAHAN AJAR IPA SMP PADA TEMA ENERGI DALAM TUBUH MENGGUNAKAN METODE 4STMD

EDUSAINS ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 166-175
Author(s):  
Gia Juniar Nur Wahidah ◽  
Sjaeful Anwar
Keyword(s):  
Concept Maps ◽  
The Body ◽  
Instructional Materials ◽  
Teaching Material ◽  
Test Results ◽  
Teaching Materials ◽  
Eligibility Criteria ◽  
Material Development ◽  
Selection Step ◽  
Selection Of

Abstract This research aims to produce science teaching materials in junior level with Energy in The Body as the theme using Four Steps Teaching Material Development  (4STMD). The material is presented in an integrated way so that students can  think holistically and contextually. The method used in this study is Research and Development. In this R&D methods is used 4STMD. There are four steps done on the development of teaching materials, the selection step, structuring step, characterization, and didactic reduction. Selection step includes the selection of indicators in accordance with the demands of the curriculum which is then developed with the selection of concepts and values that are integrated with the concept of science. Structuring step includes make macro structures, concept maps, and multiple representations. Characterization's step includes preparation instruments, then  trial to students to identify difficult concepts. The last, didactic reduction was done by neglect and the annotations in the form of sketches.The test results readability aspect instructional materials lead to the conclusion that by determining the main idea, the legibility of teaching materials reached 67%, with moderate readability criteria. Test results of feasibility aspects based on the results of questionnaires to the 11 teachers lead to the conclusion that the overall, level of eligibility teaching materials reached 91% with the eligibility criteria well. Keywords: teaching materials; energy; 4STMD Abstrak Penelitian ini bertujuan untuk menghasilkan bahan ajar IPA SMP pada tema Energi dalam Tubuh menggunakan metode Four Steps Teaching Material Development (4STMD). Materi disajikan secara terpadu sehingga memacu siswa untuk berpikir secara holistik dan kontekstual. Metode penelitian yang digunakan pada penelitian ini adalah metode penelitian dan pengembangan. Dalam penelitian dan pengembangan yang ini, digunakan metode Four Steps Teaching Material Development (4STMD). Terdapat empat tahap yang dilakukan pada pengembangan bahan ajar, yakni tahap seleksi, strukturisasi, karakterisasi, dan reduksi didaktik. Tahap seleksi meliputi pemilihan indikator yang sesuai dengan tuntutan kurikulum yang kemudian dikembangkan dengan pemilihan konsep dan nilai yang diintegrasikan dengan konsep IPA. Tahap strukturisasi meliputi pembuatan struktur makro, peta konsep, dan multipel representasi dari materi. Tahap karakterisasi meliputi penyusunan instrumen karakterisasi, kemudian uji coba kepada siswa untuk mengidentifikasi konsep sulit. Tahap terakhir, yaitu reduksi didaktik konsep terhadap konsep sulit. Reduksi didaktik yang dilakukan berupa pengabaian dan penggunaan penjelasan berupa sketsa. Hasil uji aspek keterbacaan bahan ajar menghasilkan kesimpulan bahwa berdasarkan penentuan ide pokok, keterbacaan bahan ajar mencapai 67%, dengan kriteria keterbacaan tinggi. Hasil uji aspek kelayakan berdasarkan hasil angket terhadap 11 orang guru menghasilkan kesimpulan bahwa secara keseluruhan tingkat kelayakan bahan ajar mencapai 91% dengan kriteria kelayakan baik sekali. Kata Kunci: bahan ajar; energi; 4STMD  Permalink/DOI: http://dx.doi.org/10.15408/es.v8i2.2039  

Development of High Permeability Core Materials for Embeddable Inductors in Flexible Organic Substrates

2003 ◽  
Vol 769 ◽  
Author(s):  
C. K. Liu ◽  
P. L. Cheng ◽  
S. Y. Y. Leung ◽  
T. W. Law ◽  
D. C. C. Lam
Keyword(s):  
Low Temperature ◽  
Sol Gel ◽  
Circuit Board ◽  
Organic Substrates ◽  
Circuit Boards ◽  
High Permeability ◽  
Electrical Measurements ◽  
Different Temperatures ◽  
Spiral Inductors ◽  
Ceramic Tape

AbstractCapacitors, resistors and inductors are surface mounted components on circuit boards, which occupy up to 70% of the circuit board area. For selected applications, these passives are packaged inside green ceramic tape substrates and sintered at temperatures over 700°C in a co-fired process. These high temperature processes are incompatible with organic substrates, and low temperature processes are needed if passives are to be embedded into organic substrates. A new high permeability dual-phase Nickel Zinc Ferrite (DP NZF) core fabricated using a low temperature sol-gel route was developed for use in embedded inductors in organic substrates. Crystalline NZF powder was added to the sol-gel precursor of NZF. The solution was deposited onto the substrates as thin films and heat-treated at different temperatures. The changes in the microstructures were characterized using XRD and SEM. Results showed that addition of NZF powder induced low temperature transformation of the sol-gel NZF phase to high permeability phase at 250°C, which is approximately 350°C lower than transformation temperature for pure NZF sol gel films. Electrical measurements of DP NZF cored two-layered spiral inductors indicated that the inductance increased by three times compared to inductors without the DP NZF cores. From microstructural observations, the increase is correlated with the changes in microstructural connectivity of the powder phase.

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