What is Safety: Definition and 291 Discussions

I don't know if it's the same for a car but bikes uses a starter relay to set off a starter motor which cranks the engine. Bikes have a side stand for you to lean the bike against when stationary. In case the rider tries to start the bike with side stand deployed (could cause crash if forget to...

Why can we calculate factor of safety using Strain (fail)/ Strain (allow) only if the load applied is linearly related to the stress developed within the member? What happens if the two are not related? Also, my textbook says factor of safety can also be calculated by stress (fail)/ stress...

I was reading this article about table saw safety and it seemed pretty interesting. When I watched the video attached I knew it would be appreciated here. If I ever buy a table saw, it will be one of these: What interesting examples of safety engineering have you seen?

Just wondering how much of this is political posturing and how much is hard science. http://www.sciencemag.org/news/2017/06/safety-problems-los-alamos-laboratory-delay-us-nuclear-warhead-testing-and-production

Hello everyone, I'm interested specifically what Process Safety Engineer's job is like. Like, what you must handle everyday at work, what knowledge is needed, do you find it interesting or not (and why) etc. Thank you for attention

Hi everybody, I guess most of you know of the 2009 higgs mass prediction. Nevertheless there has been important changes in the top quark mass estimations. So I wanted to know: 1 if there is any update on that prediction and if it is still in good agreement with the Higgs mass? 2 if there is at...

Homework Statement [/B] The 14mm diameter steel bolt with modulus of elasticity of 210GPa and modulus of rigidity of 85 GPa shown in the diagram below holds two components together. The thickness of the bolted interface of the components is 18mm. To 2 decimal places, for the given loading...

Are asymptotic safety and causal dynamical triangulation compatible? https://arxiv.org/pdf/1411.7712.pdf As you all know AS has problems with the holographic principle. However, the dimensional reduction obtained in asymptotic safety by using causal dynamical triangulation can make AS compatible...

https://www.amazon.com/dp/B003JH8Q98/?tag=pfamazon01-20 I plan to purchase the above laser level tool that can project laser in lines.. it has included goggles for safety. There are many devices with lasers now. May I know what is the safe laser level for the eyes and what range or values...

Hi All, would someone (hopefully a professional), who has used Fault Tree Analysis read my essay and give me some pointers for improvement? I'd really appreciate if someone could help, especially since this is the only essay I've written in recent years.

AS is a local quantum field theory, so I'm assuming that it is? What do you guys think?

If we find supersymmetry at the LHC, would this prove asymptotic safety in QG wrong? Here's the article https://arxiv.org/pdf/1508.07411v2.pdf

1. Homework Statement A load p of 5kn is applied to the tensile member shown and carried at the joint by a single 20mm diameter rivet.The angle of the shear joint is 60 degrees to the axis of the load. calculate the tensile stress in the rivet calculate the shear stress in the rivet given...

this paper https://arxiv.org/abs/1701.02311 Hypercuboidal renormalization in spin foam quantum gravity Benjamin Bahr, Sebastian Steinhaus (Submitted on 9 Jan 2017) In this article we apply background-independent renormalization group methods to spin foam quantum gravity. It is aimed at...

Robert Kennedy Jr. has been offered and has accepted the http://www.msn.com/en-us/news/politics/robert-kennedy-jr-says-hes-accepted-job-offer-from-trump/ar-BBy7z6P?li=BBnb7Kz. Trump has stated his concern for the side effects of vaccinations in the past. The inclusion of scientific...

Asymptotic safety in quantum gravity is a local QFT. According to many people, local quantum field theories cannot be correct in terms of being a quantum gravity theory. Lubos Motl outlines 4 reasons why they can't be right. "Quantum gravity cannot be described as a local field theory in the...

This is a pretty self-explanatory question; I was wondering how safe carbon-11 is for human beings; is it extremely radioactive and harmful, or safe for the average Joe to handle with the right casing/equipment. Furthermore, is owning this isotope illegal/highly regulated, or can people easily...

I am developing a machine which consists of a horizontally mounted cylindrical drum, where the door is front mounted, top opening pneumatically actuated (Picture enclosed). The door is lifted up by the pneumatic cylinder. Now there is an obvious possibility of the door crashing down if the air...

http://arxiv.org/abs/1609.04813 Quantum gravity on foliated spacetime - asymptotically safe and sound Jorn Biemans, Alessia Platania, Frank Saueressig (Submitted on 15 Sep 2016) Asymptotic Safety provides a mechanism for constructing a consistent and predictive quantum theory of gravity valid on...

can Loop Quntuam gravity be merged with Asymptotic safety scenario in gravity into a single theory of QG, one that has both concepts ? i.e if you start with Loop Quntuam gravity in 4D, can you show that it is also implies Asymptotic safety scenario in gravity in 4D? are there any papers...

Hi guys! I am fairly new to the forums so thank you for having me here :) I just wanted to ask some of you guys here who have a better knowledge about high voltage capacitors than me. I am creating a lightning impulse voltage generator as my final year project and have been provided with most...

What is not one of those fields? As long as a significant fraction of the population would agree to a law that bans atoms, ... [split from this thread: https://www.physicsforums.com/threads/stunning-reversal-in-sweden-re-nuclear.875103/ ]

Hi, I need to get some acetylene so I can calibrate our GC, the university has some in another department which I could possibly ask to have. I only need to inject very small quantities into the GC. I was wondering if anyone is familiar with this gas? If I ask the other department for it, I...

I've been accepted by the PhD program at my safety school (where I am completing my undergrad), and have been declined admission at my reach schools. While my safety school's offer is solid, I would prefer to attend a better school in a different city. I am still completing research for my...

Homework Statement https://drive.google.com/file/d/0BxPEJS0qVOpeWENSREI1RlNsNDQ/view?usp=sharing A hub is connected to a shaft with a shrink fit (pressurized oil assembly, grease removed). The material of the hub is quenched and tempered steel (ReH = 450 N/mm2) and the material of the shaft...

Hi, my friend near me, has a basement and we are located in a part of our country that is NOT KNOWN if it has high soil radon concentrations. However our area is not listed in the high concentrations areas. His basement floor is about 3 meters from top ground and has reinforced concrete walls...

I'm not getting something, I'm looking for some hints.Component classified as in infinite plate. Maximum working stress is 50% of yield strength. Has crack 10.5mm long. Cyclic loading - mode 1. Is the crack acceptable? At what length the growing crack exceeds the safety factor? I just want...

Hello, I am looking for scientific articles about particle accelerators safety systems, that posted at scientific journals. The articles I'm looking for should be about safety while the operation of the accelerator, like monitoring the radiation that could be around - and the process that...

https://www.washingtonpost.com/graphics/local/metro-lenfant-incident/?hpid=hp_no-name_graphic-story-b%3Ahomepage%2Fstory I am impressed by this article in today's Washington Post. In my memory, this is the most notable case since the NASA Challenger O-ring disaster that attempted to make the...

Homework Statement the tube has ID of 450mm, t= 6mm, OD= 462mm, pressure is 1.2MPa This is based on ASTM A36 steel, which have Ultimate Tensile strength 400-550MPa Yield Tensile strength 250Mpa Modululs of Elasticity 200Gpa Shear Modulus 79.3GPa Determine the factor of...

I'm going to perform a small scale electrolysis experimenter of water. I want to find out how the rates of the gases are produced when the amount of electrolyte added to the water is changed. I'm going to use baking soda (NaHCO3) as the electrolyte but I just wanted to make sure that I won't be...

the paper Asymptotic safety of gravity and the Higgs boson mass Mikhail Shaposhnikova, , , Christof Wetterichb predicts the Higgs mass. it also forms the framework of the neutrino minimal standard model. any research papers comparing Asymptotic Safety Scenario in QG vs LQG? does anyone here...

Hi, I'm currently puzzled on a question as I don't have/know the equation required to find the answer. The question is as follows:- Several sections of the structure are to be held together using bolts, determine the suitability of the proposed material given the following: The material for the...

It is commons practice to dump mine tailings in an area near a mine. In areas where it rains, water may accumulate behind burms and the tailings which form an earthen dam. In valleys, lakes can form behind dams leading to potential failures...

Hello everyone, I own a handheld UV lamp, it looks like this: I've been using it for my hobby interests, like finding out what luminescent materials at home etc. Recently a friend of mine told me that germ killing uv light could be dangerous to sensitive retina parts. I know that this...

Hello all, I am under the process of designing the Pressure safety valve ,the core component of PRV is spring.just i want to know about the spring design .For eg my max allowable pressure is 5 bar, then i want to set the spring to stay uncompressed at 5 bar and the spring has to compress after...

Greetings all, Just thought I'd hear you out on a decision I'm trying to make before applying to graduate school this fall, however going to keep it vague so it doesn't come around to bite me in the butt. I did an REU in physics sub-field A at a school which is #1 in the nation for sub-field...

I recently received a 200g sample of pure (99.99%) bismuth for my little element collection. This thing is so cool! It was all broken in pieces and almost powdered, so i melted it into a beautiful ingot using my kitchen stove. Is this metal safe to touch and/or handle with bare, unprotected...

Good day , could someone please point me to a device that would have say two wire terminals and could interrupt the flow of current between them when a dangerous temperature is reached? the idea is simple , I built a lamp and I need some failsafe mechanism that would turn the lamp off when it...

Does anyone know if there's a backup linkage between the ball nut and the steering pinion so that the nut doesn't lock up the rack if the power goes out? Thanks.

Homework Statement A 100 kg man is walking on a tight cable. His safety harness has a strap that is attached to an overhead cable that will allow him to fall 1 meter before stopping him from falling any further. What is the force on the strap when it stops his fall at 1 meter. Homework...

I am working on a high pressure (280 bar - 4000 psig), high temperature (250 C - 480 F) system and I need a safety device that can vent through a 6" diameter connection. I would love some feedback on viable and practical solutions for this application. I am considering a valve, but I am not...

Hello, I'm thinking about creating a temporary refrigeration device for cooling items in a hot enclosure (i.e closed car in the sun), and I was thinking about using on-demand NH3NO4 as the cooling agent. I understand how the reaction works and the implications of using the chemical, but I'm more...

So, you'll have to forgive me, but I am an engineer, not a physicist, but I take an interest in quantum gravity. My understanding is primarily conceptual, not mathematical. So if my question is dumb, I apologize. Ok, here goes: I'm aware of Zwi Bern's conjectured color-kinematics duality...

I have been thinking about racecar safety, specifically protecting the driver's waist down area. I was thinking of a transmission tunnel, firewall area, and floor board (just by pedals) Here's The Idea: What if I used a Carbon Fibre/ Kevlar weave to be flexable into the position you want then...

Hey, I've been lurking in the forums for a while and would still consider myself pretty new to the forums. I just want to know how many of you guys ride a motorcycle? What is your favorite style? How many of you know too much kinematics in order to ride a motorcycle safely? :DD Also how many...

Hi! I'm part of a team doing an engineering project to design a device to detect eye blinking while a patient in the hospital is sleeping. We have tried to use TCRT5000 sensor (http://www.vishay.com/docs/83760/tcrt5000.pdf) in the prototype and it works like charm ! However, since the...

A hole in the LHC's vacuum bubble safety argument One of the four specific risks considered in the most recent official safety review for the Large Hadron Collider (LHC) is the possibility that LHC collisions could trigger a transition to a lower-energy vacuum state. The current review by the...

I am working on identifying an issue with blown fuses in a subwoofer for a friend. The subwoofer is a Velodyne SPL-R10. The subwoofer has blown several fuses and I am attempting to locate any loose connections that may have caused a short. I am very inexperienced with complex circuits such as...

Homework Statement Rigid beam ABC is supported as shown in the figure. The pin connections at B, C, and D are each double shear connections, and the ultimate shear strength of the pin material is 640 MPa. Tie rod (1) has a yield strength of 350 MPa. A uniformly distributed load of w = 11 kN/m...