Prediction And Control Of Air Overpressure From Blasting In Hong Kong

An English language translation of Professor Wang’s comments is given below:

1. GB 6722-2003, Clause 6.8.3 on “Noise Control”. This is about the noise that is audible, that it does not include noise that is of low frequencies (<20 Hz) and ultra high frequencies. In the measuring equipment, there is a filter that would filter out the low frequencies parts, and we normally denote such measurements by dB. Clause 6.8.3.1 of the Regulations states that the “Blasting noise is a kind of intermittent impulsive noise. For urban blasting, every impulsive noise should be controlled to less than 120 dB”. The unit of measurement here should be dBA.

The air overpressure here means the peak value for the full frequency band and the unit of measurement is dBL (linear scale). This can also be represented as pressure value in Pa. Clause 6.3.2 states that safe allowable standard of air overpressures: for human is 2000 Pa, and for structures the values are given in Table 6....

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Wildfire Fighting Near High-voltage Electric Transmission Lines Owned By PG&E

1. FIRE FIGHTING OPERATIONS 100 FEET BEYOND THE OUTER MOST WIRE OF AN ELECTRIC TRANSMISSION LINE REQUIRE NO UNUSUAL TACTICS

Tactics should consider transmission lines to be an exposure requiring protection when threatened by fire. When possible, establish a Control Line to prevent the spread of fire into the area within 100 feet of and parallel to the edge of the outer most phase conductor. Smoke, ash, and incidental mist from fire fighting operations can contaminate the insulators on transmission structures. This contamination may cause a short-circuit to occur at the structure, creating an electrical hazard. Maintain a minimum radial distance of 35 feet between firefighters (and vehicles) and transmission structures to protect fire fighting personnel from this electrical hazard.

2. FIRE FIGHTING TACTICS WITHIN 100 FEET OF THE OUTER MOST WIRE OR UNDER TOWER LINES REQUIRE SPECIAL TACTICS FOR FIREFIGHTER SAFETY

If the grass or brush fire has extended to the area within 100 feet of the outer most ...

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Explosives Control | A Forgotten Management Function?

1 INTRODUCTION

StrataGold Corporation (SGC), a directly held, wholly owned subsidiary of Victoria Gold Corp., has proposed to construct, operate, close and reclaim a gold mine in central Yukon. The Eagle Gold Project (Project) is located 85 km from Mayo, Yukon using existing highway and access roads. The Project will involve open pit mining and gold extraction using a three stage crushing process, heap leaching, and a carbon adsorption, desorption, and recovery system over the mine life. During operations, the open pit will be developed using standard drill and blast technology. Ore will be transported from the open pit by haul truck and delivered to the first stage crushing plant (the primary crusher), situated on the north side of the open pit rim. Waste rock will be removed from the open pit by haul truck and delivered to one of two waste rock storage areas (Platinum Gulch or Eagle Pup WRSAs). Ore will be crushed to a passing 80 percent (P80) particle size of 6.5 mm...

Additional Resource: Eagle Gold Project Explosives Management Plan (1549 downloads )

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The Daily Profiler | The False Confession of Todd Kohlhepp

There is no question that Todd Kohlepp is a serial killer, a sadistic one, and very psychopathic. He is also a pathological liar as is a common trait of psychopaths. He got caught red-handed with a girl chained in a container in his backyard. She immediately told the police that he had killed her boyfriend and another couple, all their bodies buried on his property. The police didn't need a confession to convict him; the evidence and live witness could do that job just fine and, if this case went to trial, it was clearly a slam-dunk conviction worthy of the death penalty.

Only the serial homicides didn't go to trial. Todd Kohlhepp took a plea deal that got him out of the death penalty in exchange for....supposedly saving the families from the agony of a long, public trial and saving the state money...but, wait, there is more.....confessing to the 2003 Superbike mass murder that had long dogged the police with their failure to solve the case.

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Explosion Simulations/Structural Analysis With FLACS and USFOS

Abstract A structural analysis performed by Scandpower combining explosion simulations and structural analysis utilising the the computer tools USFOS and FLACS is described. As of today, the most common procedure for elastic and plastic explosion response analyses is to define the explosion load as a uniform pressure vs. time function for all surfaces and elements in the model. Capabilities of the computer tools FLACS and USFOS allow for a more refined approach, recognizing that for large geometries explosion pressure will vary in both time and spatial domain. USFOS (Ultimate Strength for Offshore Structures) (Ref. /1/) is a leading computer program for nonlinear static and dynamic analysis of space frame structures. The program accurately simulates the collapse process, from the initial yielding, through to the formation of a complete collapse mechanism and the final toppling of the structure. FLACS (FLame ACcellerator Simulator) (Ref. /2, 3/) is a computational fluid dynamics (CFD) tool for modeling of ventilation, gas dispersion and explosions in complex process areas. The FLACS code allows for monitoring...

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Simulation And Modelling Of Water Spray In The 3d Explosion Simulation Program FLACS

2. Summary

In a gas processing plant and in offshore platforms a gas explosion could have serious consequences, and it is therefore essential to have mitigation systems that can prevent and/or reduce unwanted scenarios. One such mitigating technique that has proved to be effective is water spray and deluge systems. Since such systems often already are installed in most industries to use in a fire situation, this has become an attractive method in fighting gas explosions. Experimental work has been done with the use of water spray, and the main results are that activation of water spray before an ignition can reduce rapid flame acceleration that otherwise could result in high-pressure build-up. Because the consequences of a gas explosion depends on many different parameters, a numerical model was developed that could handle different scenarios and give good results. The model was named FLACS (FLame Acceleration Simulator), and is a tree-dimensional gas explosion and gas-dispersing tool. FLACS is a Computational Fluid Dynamics (CDF) code....

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Fourth Amendment–Protective Sweep Doctrine: When Does the Fourth Amendment Allow Police Officers to Search the Home Incident to a Lawful Arrest

I. INTRODUCTION

In Maryland v. Buie,' the Supreme Court held that the fourth amendment permits an officer executing an arrest warrant in a private awelling to search rooms other than the room in which the arrest is made, whenever the searching officer possesses a reason- able belief, based on specific and articulable facts, that the adjacent rooms harbor another individual posing a danger to those on the arrest scene. The majority based its approval of this "protective sweep" on the "reasonable suspicion" exception to traditional fourth amendment searches first articulated in Terry v. State of Ohio. The majority thus extended the Terry holding, which permits officers to conduct a protective, warrantless search of a person, to "protective sweeps" conducted by police officers incident to a lawful, in home arrest. Conversely, the Buie dissent argued that the Terry test does not extend to searches of the home and that the fourth amendment war- rant and probable cause requirements should be applied to protective...

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The Brutal Reality | Harmful Psychiatric Treatments

The psychiatric profession purports to be the sole arbiter on the subject of mental health and “diseases” of the mind. The facts, however, demonstrate otherwise:

1. PSYCHIATRIC “DISORDERS” ARE NOT MEDICALDISEASES.
In medicine, strict criteria exist for calling a condition a disease: a predictable group of symptoms and the cause of the symptoms or an understanding of their physiology (function) must be proven and established. Chills and feverare symptoms. Malaria and typhoid are diseases. Diseases are proven to exist by objective evidence and physical tests. Yet, no mental “diseases” have ever been proven to medically exist.

2. PSYCHIATRISTS DEAL EXCLUSIVELY WITH MENTAL “DISORDERS,” NOT PROVEN DISEASES.
While mainstream physical medicine treats diseases, psychiatry can only deal with “disorders.” In the absence of a known cause or physiology, a group of symptoms seen in many different patients is called a disorder or syndrome. Harvard Medical School’s Joseph Glenmullen, M.D., says that in psychiatry, “all of its diagnoses are merely syndromes [or disorders], clusters of symptoms ...

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