scholarly journals Studies on the Electro-Impulse De-Icing System of Aircraft

Aerospace ◽  
2019 ◽  
Vol 6 (6) ◽  
pp. 67 ◽  
Author(s):  
Xingliang Jiang ◽  
Yangyang Wang
Keyword(s):  
Three Dimensional ◽  
Leading Edge ◽  
Central Position ◽  
Test Results ◽  
Aircraft Icing ◽  
The Finite Element Method ◽  
Starting Time ◽  
Single Coil ◽  
Selection Of ◽  
Icing Prediction

In order to solve the accidents caused by aircraft icing, electro-impulse de-icing technology was studied through numerical simulation and experimental verification. In addition, this paper analyzed in detail the influence of the number, placement arrangement, and starting time of pulse coils on the de-icing effect, which plays a guidance role in the design and installation of the subsequent electro-impulse de-icing system. In an artificial climate chamber, the new de-icing criteria were obtained by tensile test, and the platform for the electro-impulse de-icing system was built. Replacing the skin with an aluminum plate, an electro-impulse de-icing system with a single coil was used. A three-dimensional skin-ice layer model was established by using Solidworks software. The finite element method was adapted. Through comparison between the de-icing prediction results and the test results in the natural environment, it was proven that the calculation process of de-icing prediction was correct, which laid a theoretical foundation for the selection of the number, placement arrangement, and starting time of the pulse coils. Finally, in this paper, by choosing the leading edge of NACA0012 wing as the research object, the influence of the number, placement arrangement, and starting time of pulse coils on the de-icing effect was analyzed. The results show that to get a better de-icing effect, the electro-impulse de-icing system with two impulse coils should be selected. The two coils were installed in the central position of the top and bottom surfaces of the leading edge, respectively. In addition, one of the impulse coils started working 1200 μs later than the other one.

Shockwave and Noise Abatement of Transonic Fans

2004 ◽  
Author(s):  
Liping Xu
Keyword(s):  
Shock Wave ◽  
Noise Reduction ◽  
Three Dimensional ◽  
Leading Edge ◽  
Aerodynamic Performance ◽  
Test Results ◽  
Shock Strength ◽  
Noise Levels ◽  
Noise Abatement ◽  
Blade Passage

The aerodynamic sources of the forward tone noise of transonic civil fans are analysed. The leading edge shockwave near the rotor tip section is identified as the main source of tone noise. By comparing the tone noise levels of the same fan operating at two different working lines, numerical calculations show that on the lower working line, the main passage shockwave is swallowed and locked into the blade passage, and the fan blades act as a shield to prevent the strong passage shock wave from propagating upstream. The calculations show that, by running the fan at a lower working line, up to 6 db abatement in the blade passing frequency (BPF) tone can be achieved through shielding the shockwave. With three dimensional CFD it is possible to design swept rotors which have desired shockwave structures near the tip region. Fan rotors with different swept leading edges have been designed to study this effect and comparisons in aerodynamics performances as well as the tone noise levels are made. It is predicted that in a swept rotor the leading edge shock strength can be further weakened and up to 5db further reduction in tone noise is possible. With a more secure shockwave shielding, a forward swept rotor has the combination of better aerodynamic performance and better noise abatement feature. The design and test results of a three dimensional fan rotor LNR2, featuring localised forward swept rotor are presented. Rig test results show that although the noise reduction through shock shielding has been demonstrated, the aerodynamics and noise are complicated by the problems specific to such localised forward swept fan.

scholarly journals Analysis Of Deformation And Microstructural Evolution In The Hot Forgingof The Ti-6Al-4V Alloy

2015 ◽  
Vol 60 (3) ◽  
pp. 1639-1648 ◽  
Author(s):  
M. Kukuryk
Keyword(s):  
Effective Strain ◽  
Metal Flow ◽  
Three Dimensional ◽  
Test Results ◽  
The Finite Element Method ◽  
Rigid Plastic ◽  
Microstructure Parameters ◽  
Thermal Phenomena ◽  
Tool Types

Abstract The paper presents the analysis of the three-dimensional strain state for the cogging process of the Ti-6Al-4V alloy using the finite element method, assuming the rigid-plastic model of the deformed body. It reports the results of simulation studies on the metal flow pattern and thermal phenomena occurring in the hot cogging process conducted on three tool types. The computation results enable the determination of the distribution of effective strain, effective stress, mean stress and temperature within the volume of the blank. This solution has been complemented by adding the model of microstructure evolution during the cogging process. The numerical analysis was made using the DEFORM-3D consisting of a mechanical, a thermal and a microstructural parts. The comparison of the theoretical study and experimental test results indicates a potential for the developed model to be employed for predicting deformations and microstructure parameters.

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  

Comparison of Conventional and Pontic Fixed Partial Dentures Over Implants Using the Finite Element Method: Three-Dimensional Analysis of Cortical and Medullary Bone Stress

2020 ◽  
Vol 46 (3) ◽  
pp. 175-181
Author(s):  
Marcelo Bighetti Toniollo ◽  
Mikaelly dos Santos Sá ◽  
Fernanda Pereira Silva ◽  
Giselle Rodrigues Reis ◽  
Ana Paula Macedo ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Medullary Bone ◽  
Principal Stresses ◽  
Bone Stress ◽  
Bone Damage ◽  
Rehabilitation System ◽  
Minimum Requirements

Rehabilitation with implant prostheses in posterior areas requires the maximum number of possible implants due to the greater masticatory load of the region. However, the necessary minimum requirements are not always present in full. This project analyzed the minimum principal stresses (TMiP, representative of the compressive stress) to the friable structures, specifically the vestibular face of the cortical bone and the vestibular and internal/lingual face of the medullary bone. The experimental groups were as follows: the regular splinted group (GR), with a conventional infrastructure on 3 regular-length Morse taper implants (4 × 11 mm); and the regular pontic group (GP), with a pontic infrastructure on 2 regular-length Morse taper implants (4 × 11 mm). The results showed that the TMiP of the cortical and medullary bones were greater for the GP in regions surrounding the implants (especially in the cervical and apical areas of the same region) but they did not reach bone damage levels, at least under the loads applied in this study. It was concluded that greater stress observed in the GP demonstrates greater fragility with this modality of rehabilitation; this should draw the professional's attention to possible biomechanical implications. Whenever possible, professionals should give preference to use of a greater number of implants in the rehabilitation system, with a focus on preserving the supporting tissue with the generation of less intense stresses.

Towards Predicting Relative Belt Edge Endurance With the Finite Element Method

1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Shear Deformations ◽  
Element Analysis ◽  
Vertical Loading ◽  
Predicted Values ◽  
Element Method

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.

HUBUNGAN UMUR DAN PARITAS DENGAN PEMILIHAN ALAT KONTRASEPSI METODE OPERASI WANITA (MOW) DI POLIKLINIK KEBIDANAN RS BHAYANGKARA PALEMBANG TAHUN 2012

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
Y. Widyastuti Y. Widyastuti
Keyword(s):  
Family Planning ◽  
Medical Records ◽  
Test Results ◽  
Family Planning Services ◽  
Chi Square ◽  
Cross Sectional ◽  
Planning Methods ◽  
Chi Square Test ◽  
Family Planning Methods ◽  
Selection Of

  ABSTRACT [In advanced countries the number of permanent contraception option ( kontap ) approximately 10 % of all national family planning methods , while in Indonesia reached approximately 5.7 % . Based on data obtained from medical records Bhayangkara Hospital Palembang in 2010 the number of achievement when seen from the percentage of contraceptive use is only 9.10 % The purpose of this study is known age and parity relationship with the selection of contraceptive methods Surgery Women ( MOW ) in Palembang RS.Bhayangkara obstetrics clinic in 2012 . This study uses the analytic survey with cross sectional approach . The population in this study were women who become new acceptors were recorded in medical records at the hospital . Palembang Bhayangkara Hospitals January 1, 2012 to December 31 in 2012 . The sample in this study is part of a whole number of new acceptors ( either using contraception methods MOW and other family planning methods ) were registered in the hospital . Palembang Police Hospitals of January 1, 2012 to December 31 years of data 2012.Analisa univariate and bivariate statistical Chi - Square test with significance level α = 0.05 . The results showed there were 80 respondents ( 46.3 % ) who became MOW contraceptive acceptors , acceptors who have old age by 45 respondents ( 56.3 % ) and who has a young age by 35 respondents ( 43.8 % ) . acceptors which have high parity were 44 respondents ( 55 % ) who had low parity and a total of 36 respondents ( 45 % ) . From the results of Chi-square test value obtained ρ = 0.00 is smaller than α = 0.05 . There is a significant correlation between age and the selection of MOW Chi square test results obtained ρ value = 0.00 and there was a significant association between parity with the election MOW Chi square test results obtained ρ value = 0 , . From these results , it is expected to power health, especially family planning services at the hospital . Palembang Police Hospitals in order to improve the quality of family planning services in an effective, efficient , and safe are considered particularly suitable for users of contraception OperatingMethodWomen(MOW).                                      ABSTRAK Di negara sudah maju jumlah pilihan kontrasepsi mantap (kontap) sekitar 10% dari semua metode KB nasional, sedangkan di Indonesia baru mencapai sekitar 5,7 %. Berdasarkan data yang diperoleh dari Rekam medik  Rumah Sakit Bhayangkara Palembang tahun 2010 Jumlah pencapain tersebut jika dilihat dari persentasi penggunaan kontrasepsi MOW hanya  9,10% Tujuan penelitian ini adalah diketahuinya hubungan umur dan paritas dengan pemilihan alat kontrasepsi Metode Operasi Wanita (MOW) di poliklinik kebidanan RS.Bhayangkara Palembang Tahun 2012. Penelitian ini menggunakan metode survey analitik dengan pendekatan cross sectional. Populasi dalam penelitian ini adalah wanita yang menjadi akseptor KB Baru yang tercatat di rekam medik  di RS. Bhayangkara Palembang tanggal 1 januari 2012 sampai dengan 31 Desember  tahun 2012. Sampel dalam penelitian ini adalah sebagian dari seluruh jumlah akseptor KB Baru (baik yang menggunakan alat kontrasepsi Metode MOW maupun Metode KB lain) yang teregister di RS. Bhayangkara Palembang dari tanggal 1 januari 2012 sampai dengan 31 Desember  tahun 2012.Analisa data dilakukan secara univariat dan bivariat dengan uji statistik Chi-Square dengan tingkat kemaknaan α = 0,05. Hasil penelitian menunjukkan dari 80 responden terdapat (46,3%) yang menjadi akseptor kontrasepsi MOW, akseptor yang memiliki umur tua sebanyak 45 responden (56,3%) dan yang memiliki  umur muda sebanyak 35 responden (43,8%). akseptor yang memiliki paritas tinggi sebanyak 44 responden  (55%) dan yang memiliki  paritas rendah sebanyak 36 responden (45%). Dari hasil uji Chi square didapatkan ρ value = 0,00 lebih kecil dari α = 0,05. Ada hubungan yang bermakna antara umur dengan pemilihan MOW dari hasil uji Chi square didapatkan ρ value = 0,00 dan ada hubungan yang bermakna antara paritas dengan pemilihan MOW hasil uji Chi square didapatkan ρ value = 0,.Dari hasil penelitian ini, diharapkan kepada tenaga kesehatan khususnya pelayanan KB  di RS. Bhayangkara Palembang  agar dapat meningkatkan kualitas pelayanan KB secara efektif, efisien, dan aman yang dianggap cocok bagi penggunanya khususnya mengenai kontrasepsi Metode Operasi Wanita (MOW).    

scholarly journals Car braking effectiveness after adaptation for drivers with motor dysfunctions

2021 ◽  
Vol 11 (1) ◽  
pp. 617-623
Author(s):  
Adam Sowiński ◽  
Tomasz Szczepański ◽  
Grzegorz Koralewski
Keyword(s):  
Efficiency Index ◽  
Mathematical Function ◽  
Test Results ◽  
Braking Performance ◽  
Braking System ◽  
System Adaptation ◽  
Parametric Description ◽  
Limited Power ◽  
Braking Force ◽  
Selection Of

Abstract This article presents the results of measurements of the braking efficiency of vehicles adapted to be operated by drivers with motor dysfunctions. In such cars, the braking system is extended with an adaptive device that allows braking with the upper limb. This device applies pressure to the original brake in the car. The braking force and thus its efficiency depend on the mechanical ratio in the adapting device. In addition, braking performance depends on the sensitivity of the car’s original braking system and the maximum force that a disabled person can exert on the handbrake lever. Such a person may have limited power in the upper limbs. The force exerted by the driver can also be influenced by the position of the driver’s seat in relation to the handbrake lever. This article describes the research aimed at understanding the influence of the above-mentioned factors on the car braking performance. As a part of the analysis of the test results, a mathematical function was proposed that allows a parametric description of the braking efficiency index on the basis of data on the braking system, adaptation device, driver’s motor limitations, and the position of the driver’s seat. The information presented in this article can be used for the preliminary selection of adaptive devices to the needs of a given driver with a disability and to the vehicle construction.

What Every Neuropathologist Needs to Know: Practical Aspects and Pitfalls in Molecular Diagnosis of Brain Tumors

2021 ◽  
Author(s):  
J Stephen Nix ◽  
Cristiane M Ida
Keyword(s):  
Brain Tumors ◽  
Molecular Diagnosis ◽  
Genetic Alterations ◽  
Genetic Alteration ◽  
Molecular Testing ◽  
Test Results ◽  
Molecular Test ◽  
Molecular Tests ◽  
Clinically Significant ◽  
Selection Of

Abstract Molecular testing has become part of the routine diagnostic workup of brain tumors after the implementation of integrated histomolecular diagnoses in the 2016 WHO classification update. It is important for every neuropathologist to be aware of practical preanalytical, analytical, and postanalytical factors that impact the performance and interpretation of molecular tests. Prior to testing, optimizing tumor purity and tumor amount increases the ability of the molecular test to detect the genetic alteration of interest. Recognizing basic molecular testing platform analytical characteristics allows selection of the optimal platform for each clinicopathological scenario. Finally, postanalytical considerations to properly interpret molecular test results include understanding the clinical significance of the detected genetic alteration, recognizing that detected clinically significant genetic alterations are occasionally germline constitutional rather than somatic tumor-specific, and being cognizant that recommended and commonly used genetic nomenclature may differ. Potential pitfalls in brain tumor molecular diagnosis are also discussed.

scholarly journals Transcriptome Analyses of Myometrium from Fibroid Patients Reveals Phenotypic Differences Compared to Non-Diseased Myometrium

2021 ◽  
Vol 22 (7) ◽  
pp. 3618
Author(s):  
Emmanuel N. Paul ◽  
Gregory W. Burns ◽  
Tyler J. Carpenter ◽  
Joshua A. Grey ◽  
Asgerally T. Fazleabas ◽  
...  
Keyword(s):  
Uterine Fibroid ◽  
Three Dimensional ◽  
Uterine Fibroids ◽  
Principal Component ◽  
Leading Edge ◽  
Gene Set Enrichment ◽  
Phenotypic Differences ◽  
False Discovery ◽  
Gene Sets ◽  
High Concordance

Uterine fibroid tissues are often compared to their matched myometrium in an effort to understand their pathophysiology, but it is not clear whether the myometria of uterine fibroid patients represent truly non-disease control tissues. We analyzed the transcriptomes of myometrial samples from non-fibroid patients (M) and compared them with fibroid (F) and matched myometrial (MF) samples to determine whether there is a phenotypic difference between fibroid and non-fibroid myometria. Multidimensional scaling plots revealed that M samples clustered separately from both MF and F samples. A total of 1169 differentially expressed genes (DEGs) (false discovery rate < 0.05) were observed in the MF comparison with M. Overrepresented Gene Ontology terms showed a high concordance of upregulated gene sets in MF compared to M, particularly extracellular matrix and structure organization. Gene set enrichment analyses showed that the leading-edge genes from the TGFβ signaling and inflammatory response gene sets were significantly enriched in MF. Overall comparison of the three tissues by three-dimensional principal component analyses showed that M, MF, and F samples clustered separately from each other and that a total of 732 DEGs from F vs. M were not found in the F vs. MF, which are likely understudied in the pathogenesis of uterine fibroids and could be key genes for future investigation. These results suggest that the transcriptome of fibroid-associated myometrium is different from that of non-diseased myometrium and that fibroid studies should consider using both matched myometrium and non-diseased myometrium as controls.

Sign in / Sign up

Export Citation Format

Share Document