scholarly journals A New Optimized Solution for a Flexible Coupling with Bolts Used in the Mechanical Transmissions

Symmetry ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 171
Author(s):  
Marilena Ghiţescu ◽  
Ion-Marius Ghiţescu ◽  
Paul Nicolae Borza ◽  
Sorin Vlase
Keyword(s):  
Finite Element Method ◽  
Mechanical Response ◽  
Metal Plate ◽  
Special Shape ◽  
Flexible Coupling ◽  
Metallic Element ◽  
New Type ◽  
The Right ◽  
Functional Solution ◽  
With Screws

The paper presents a new constructive and functional solution of flexible coupling with bolts and nonmetallic intermediary elements. The bolts have a special shape in the sense that they have a milled area on a certain length equal to the width of the non-metallic element, a cylindrical area that reduces the stress concentrators at the diameter passages. The novelty of this coupling consists of the existence of one intermediary disk between two semi couplings (driver and driven semi couplings). This is fixed by the semi-coupling on the right side, the intermediary disc having milled four locations in which to mount the left, as the right has a metal plate with a special shape of eight metallic plates that are mounted with screws in the four milled places processed on the intermediate disc. The nonmetallic elements have various forms and can be made from different qualities of rubber mounted on the bolts. Eight milled bolts (four on each semi-coupling) allow the transmission of the torsion moment in both directions of rotation, in one direction becoming rigid and thus behaving like a safety coupling. Finite element method is used to obtain the mechanical response of this new type of coupling.

Performance of 4G-LTE Communication and Navigation System in Blended Wing-Body UAS

2019 ◽  
Vol 8 (4) ◽  
pp. 9538-9542
Keyword(s):  
Satellite Communication ◽  
Line Of Sight ◽  
Multiple Factors ◽  
The World ◽  
New Type ◽  
Blended Wing Body ◽  
4G Lte ◽  
The Right ◽  
And Control ◽  
Technology Demonstrator

In vision of searching for the right Unmanned Aerial System (UAS) for a specific mission, there are multiple factors to be considered by the operator such as mission, endurance, type of payload and range of the telemetry and control. This research is focusing on extending control range of the UAS by using 4G-LTE network to enable beyond-line-of-sight flying for the commercial UAS. Major UAS such Global Hawk, Predator MQ-1 are able to fly thousands of kilometers by the use of satellite communication. However, the satellite communication annual license subscription can be very expensive. With this situation in mind, a new type of flight controller with 4G-LTE communication has been developed and tested. Throughout the research, blended-wing-body (BWB) Baseline B2S is used as the platform for technology demonstrator. Result from this analysis has proven that the proposed system is capable to control a UAS from as far as United Kingdom, with a latency less than 881 ms in average. The new added capability can potentially give the commercial UAS community a new horizon to be able to control their UAS from anywhere around the world with the availability of 4G-LTE connection

Numerical modelling of the crack-pore interaction and damage evolution behaviour of rocklike materials with pre-existing cracks and pores

2020 ◽  
pp. 105678952098387
Author(s):  
PLP Wasantha ◽  
D Bing ◽  
SQ Yang ◽  
T Xu
Keyword(s):  
Principal Stress ◽  
Damage Evolution ◽  
Shear Failure ◽  
Mechanical Response ◽  
Distribution Patterns ◽  
Stress Distributions ◽  
Compressive Stresses ◽  
Major Principal Stress ◽  
The Right ◽  
Macroscopic Failure

The combined effect of pre-existing cracks and pores on the damage evolution behaviour and mechanical properties of rocklike materials under uniaxial compression was numerically studied. Simulations of cracks and pores alone showed that increasing crack length and pore diameter decrease uniaxial compressive strength (UCS) and elastic modulus. Subsequent simulations considered two types of combinations of pre-existing cracks and pores – two cracks either side of a centric pore, and two pores either side of a centric crack – and the distance between cracks and pores was changed. In the case of two cracks at either side of the pore, UCS increased only slightly when the distance between the cracks and pore was increased. This was attributed to the more profound effect of the presence of the pore on UCS, and was confirmed by the progressive crack development characteristics and the major principal stress distribution patterns, which showed that the cracks initiated from the tips of the two pre-existing cracks made little or no contribution to the ultimate macroscopic failure. In contrast, models with two pores at either side of a centric crack showed a marked dependency of UCS on the distance between the pores and the crack. Cracks propagating from pre-existing pores made a greater contribution to the ultimate macroscopic failure when the pores were close to the centric crack and the effect gradually diminished with increasing space between pre-existing pores and the centric crack. Major principal stress distributions showed an asymmetric mobilisation of compressive stresses at the right and left sides of the two pores, favouring macroscopic shear failure when they were close to the centric crack which had led to a lower UCS. Overall, this study presents some critical insights into crack-pore interaction behaviour and the resulting mechanical response of rocklike materials to assist with the design of rock structures.

Regeneration of Hypogastric Nerve Using a Polyglycolic Acid (PGA)-Collagen Nerve Conduit Filled with Collagen Sponge Proved Electrophysiologically in a Canine Model

2003 ◽  
Vol 26 (3) ◽  
pp. 245-251 ◽  
Author(s):  
T. Ito ◽  
T. Nakamura ◽  
K. Suzuki ◽  
T. Takagi ◽  
T. Toba ◽  
...  
Keyword(s):  
Canine Model ◽  
Polyglycolic Acid ◽  
Collagen Sponge ◽  
Intraluminal Pressure ◽  
Nerve Conduit ◽  
Hypogastric Nerve ◽  
Spermatic Duct ◽  
New Type ◽  
Conduit Diameter ◽  
The Right

The hypogastric nerve (HGN) is a sympathetic nerve in the peritoneal cavity and controls urinary and seminal functions. In this study, the regeneration of HGN was determined by using a new type of an artificial nerve conduit, polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge in two dogs. A PGA-collagen nerve conduit (diameter=2mm) was interposed in a 10 mm gap of the right HGN. The regeneration of the HGN was evaluated electrophysiologically 8 months after the operation. The intraluminal pressure of spermatic duct and the bladder neck were elevated 80 mmHg and 25 mmHg respectively by the stimulation across the regenerated HGN. The prostate contraction was also elicited. The responses diminished after the excision of the regenerated portion of HGN. These results proved the regeneration of HGN and this nerve conduit will be great help for patients who suffer from urinary and seminal disturbances.

Myocyte Transdifferentiation

2000 ◽  
Vol 124 (2) ◽  
pp. 287-290 ◽  
Author(s):  
Giulia d'Amati ◽  
Cira R. T. di Gioia ◽  
Carla Giordano ◽  
Pietro Gallo
Keyword(s):  
Right Ventricular ◽  
Transplant Patient ◽  
Arrhythmogenic Right Ventricular Cardiomyopathy ◽  
Ventricular Myocardium ◽  
Ventricular Cardiomyopathy ◽  
Familial Dilated Cardiomyopathy ◽  
Familial Cardiomyopathy ◽  
New Type ◽  
The Right ◽  
Gross Examination

Abstract Adipose substitution of ventricular myocardium is characteristic of arrhythmogenic right ventricular cardiomyopathy, but is also found in other heart conditions. It is thought to be a consequence of myocyte loss due to myocarditis or other noxious stimuli. We describe a unique case of cardiomyopathy with a morphologic pattern suggestive of transdifferentiation from myocytes to mature adipocytes. Gross, histologic, and ultrastructural examination were performed on the heart of a female transplant patient with a clinical diagnosis of familial dilated cardiomyopathy. Gross examination showed fibroadipose substitution of the left ventricle and adipose replacement of the right. Histology, immunohistochemistry, and ultrastructure were highly suggestive of transdifferentiation from cardiac muscle to adipose tissue. Myocyte transdifferentiation could represent an alternative pathogenetic pathway to the myocyte-loss and adipose-replacement mechanism in arrhythmogenic right ventricular cardiomyopathy, or it could be the basis of a new type of familial cardiomyopathy.

Introduction

2021 ◽  
pp. 1-18
Author(s):  
Charles Devellennes
Keyword(s):  
News Media ◽  
State Violence ◽  
The Political ◽  
Political Leaders ◽  
The Social ◽  
Fundamental Challenge ◽  
New Type ◽  
The Right ◽  
Over Time

This chapter gives introduces the gilet jaunes. The gilets jaunes, a group of French protesters named after their iconic yellow vests donned during demonstrations, have formed a new type of social movement. The gilets jaunes have been variously interpreted since they began their occupation of French roundabouts. They were at first received with enthusiasm on the right of the French political establishment, and with caution on the left. The fourth weekend saw scenes of violence erupt on the Champs Élysées, notably around and within the Arc de Triomphe, which towers over the first roundabout built in France. The headlines of newspapers and stories of the news media became almost exclusively focused on the violence of the protests. Images of state violence became ever-present on Twitter and independent media outlets, making it clear that it was the use of disproportionate force by police units that was at the centre of the events. The chapter explains that the aim of the book is to show that the use of violence is not the only tale to be told about the role of the protesters in the contemporary French context. Their contribution to the political landscape of France is quite different. They have provided a fundamental challenge to the social contract in France, the implicit pact between the governed and their political leaders. The movement has seen the numbers of participants diminish over time, but the underlying tension between the haves and the have-nots, the winners of globalization and those at risk of déclassement [social downgrading], are enduring and persistent.

Onlay Silicone and Hydroxyapatite-Tricalciumphosphate Composite (HAP-TCP) Blocks Interfere with Nasal Bone Growth in Rabbits

1995 ◽  
Vol 32 (4) ◽  
pp. 282-289
Author(s):  
Minoru Arakaki ◽  
Shunichi Yamashita ◽  
Mehmet Mutaf ◽  
Shinji Naito ◽  
Tohru Fujii
Keyword(s):  
Bone Tissue ◽  
Bone Growth ◽  
Nasal Bone ◽  
Growth Period ◽  
Blood Biochemistry ◽  
Hydroxyapatite Ceramic ◽  
Cross Sectional ◽  
Porous Hydroxyapatite ◽  
New Type ◽  
The Right

We investigated how a new type of synthetic porous hydroxyapatite ceramic (HAP-TCP) acts when it is implanted in growing membranous bone. Seventy-six New Zealand White infant male rabbits (4-week-olds) were used. Rabbits received HAP-TCP block or silicone block implantation in their right nasal bone. The left nasal bone was used for a sham. Serial or cross-sectional examinations by morphometry, radiology, blood biochemistry, and histology were carried out. Both the HAP-TCP and silicone groups exhibited no systemic growth disturbance in terms of morphometry and blood biochemistry. Dual energy x-ray absorptiometry (DEXA) revealed, however, a decrease in the bone mineral content (BMC) of the right nasal bone in the silicone group. Histology revealed a superior affinity of HAP-TCP to bone tissue than that of silicone. When a HAP-TCP block was implanted under the periosteum it bonded directly to bone tissue. However, sinking of the implants into the bone tissue were noted both in the HAP-TCP and the silicone groups in longitudinal observation. These results suggest that although HAP-TCP has superior affinity to bone tissue, this by itself is not enough sufficient reason to believe that HAP-TCP can be effectively applied during the growth period.

scholarly journals A New Coated Nitinol Occluder for Transcatheter Closure of Ventricular Septal Defects in a Canine Model

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Yong Zhou ◽  
Feng Chen ◽  
Xinmiao Huang ◽  
Xianxian Zhao ◽  
Hong Wu ◽  
...  
Keyword(s):  
Ventricular Septal Defect ◽  
Septal Defect ◽  
Thrombus Formation ◽  
Canine Model ◽  
Control Group ◽  
New Type ◽  
Good Biocompatibility ◽  
The Right ◽  
Microscopy Examination

Aims. This study evaluated feasibility and safety of implanting the polyester-coated nitinol ventricular septal defect occluder (pcVSDO) in the canine model.Methods and Results. VSD models were successfully established by transseptal ventricular septal puncture via the right jugular vein in 15 out of 18 canines. Two types of VSDOs were implanted, either with pcVSDOs (n=8) as the new type occluder group or with the commercial ventricular septal defect occluders (VSDOs,n=7, Shanghai Sharp Memory Alloy Co. Ltd.) as the control group. Sheath size was 10 French (10 Fr) in two groups. Then the general state of the canines was observed after implantation. ECG and TTE were performed, respectively, at 7, 30, 90 days of follow-up. The canines were sacrificed at these time points for pathological and scanning electron microscopy examination. The devices were successfully implanted in all 15 canines and were retrievable and repositionable. There was no thrombus formation on the device or occurrence of complete heart block. The pcVSDO surface implanted at day 7 was already covered with neotissue by gross examination, and it completed endothelialization at day 30, while the commercial VSDO was covered with the neotissue in 30th day and the complete endothelialization in 90th day.Conclusion. The study shows that pcVSDO is feasible and safe to close canine VSD model and has good biocompatibility and shorter time of endothelialization.

Piezoelectric “Kumihimo-gumi” sensor fabricated by braiding method using piezoelectric poly-L-lactic acid fiber

2020 ◽  
Vol 557 (1) ◽  
pp. 43-57 ◽  
Author(s):  
Y. Tajitsu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Lactic Acid ◽  
Polyethylene Terephthalate ◽  
Wearable Sensor ◽  
The Finite Element Method ◽  
Complex Motion ◽  
Calculation Results ◽  
New Type ◽  
Plla Fiber

We have developed a piezoelectric braided cord consisting of a conducting fiber yarn core, piezoelectric poly-l-lactic acid (PLLA) fiber yarn and a polyethylene terephthalate (PET) middle sheath, and a conducting fiber outer shield (piezoelectric PLLA braided cord). Actually, we made various types of piezoelectric PLLA braided cords using Japanese traditional braiding method called as Kumihimo-gumi in Japanese. Furthermore, by optimization based on the calculation results for each type of piezoelectric PLLA Kumihimo-gumi obtained by the finite element method (FEM), we were able to develop a new type of piezoelectric PLLA braided cord with a sensing function for complex motion (piezoelectric PLLA Kumihimo-gumi). Finally, we developed a new wearable sensor for a selfie stick which is a popular smartphone accessory, fabricated from a piezoelectric PLLA Kumihimo-gumi.

“Just-in-Time” Personal Preparedness: Downloads and Usage Patterns of the American Red Cross Hurricane Application During Hurricane Sandy

2016 ◽  
Vol 10 (5) ◽  
pp. 762-767 ◽  
Author(s):  
Thomas D. Kirsch ◽  
Ryan Circh ◽  
Richard A. Bissell ◽  
Matthew Goldfeder
Keyword(s):  
Smart Phone ◽  
Hurricane Sandy ◽  
Red Cross ◽  
Just In Time ◽  
American Red Cross ◽  
Before And After ◽  
Usage Patterns ◽  
New Type ◽  
The Right ◽  
Real Time Information

AbstractObjectivePersonal preparedness is a core activity but has been found to be frequently inadequate. Smart phone applications have many uses for the public, including preparedness. In 2012 the American Red Cross began releasing “disaster” apps for family preparedness and recovery. The Hurricane App was widely used during Hurricane Sandy in 2012.MethodsPatterns of download of the application were analyzed by using a download tracking tool by the American Red Cross and Google Analytics. Specific variables included date, time, and location of individual downloads; number of page visits and views; and average time spent on pages.ResultsAs Hurricane Sandy approached in late October, daily downloads peaked at 152,258 on the day of landfall and by mid-November reached 697,585. Total page views began increasing on October 25 with over 4,000,000 page views during landfall compared to 3.7 million the first 3 weeks of October with a 43,980% increase in views of the “Right Before” page and a 76,275% increase in views of the “During” page.ConclusionsThe Hurricane App offered a new type of “just-in-time” training that reached tens of thousands of families in areas affected by Hurricane Sandy. The app allowed these families to access real-time information before and after the storm to help them prepare and recover. (Disaster Med Public Health Preparedness. 2016;page 1 of 6)

Modelling of Joint Interface of Turn-Milling Centre Based on Rigid-Flexible Coupling System

2011 ◽  
Vol 186 ◽  
pp. 412-417
Author(s):  
Li Da Zhu ◽  
Jian Qiu ◽  
Yue Hu Wang ◽  
Jiang Li ◽  
Wan Shan Wang
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Dynamic Models ◽  
Dynamic Performance ◽  
Joint Interface ◽  
Flexible Joints ◽  
Flexible Coupling ◽  
Plane Contact ◽  
Coupling System ◽  
Turn Milling

The mathematic models describing various joints of whole machine are founded to research dynamic performance of turn-milling center based on rigid-flexible coupling system. The various joint interfaces including the conical and cylinder contact, plane contact and fixed connection are regarded as flexible joints by using the spring and damping unit and the equivalent dynamic models of joint interfaces are built by finite element method based on different connection modes. Therefore, these mathematic models are used as references and foundations for research on dynamic performance of turn-milling center next stage.

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