Wednesday, March 16, 2011
RADIATION IN TOKYO NOT A THREAT TO HUMAN HEALTH
TOKYO: Japan's nuclear crisis appeared to be spinning out of control on Wednesday after workers withdrew briefly from a stricken power plant because of surging radiation levels and a helicopter failed to drop water on the most troubled reactor.
In a sign of desperation, the police will try to cool spent nuclear fuel at one of the facility's reactors with water cannon, which is normally used to quell riots.
Early in the day another fire broke out at the earthquake-crippled facility, which has sent low levels of radiation wafting into Tokyo in the past 24 hours, triggering fear in the capital and international alarm.
Japan's government said radiation levels outside the plant's gates were stable but, in a sign of being overwhelmed, appealed to private companies to help deliver supplies to tens of thousands of people evacuated from around the complex.
"People would not be in immediate danger if they went outside with these levels. I want people to understand this," chief cabinet secretary Yukio Edano told a televised news conference, referring to people living outside a 30 km (18 miles) exclusion zone. Some 140,000 people inside the zone have been told to stay indoors.
Workers were trying to clear debris to build a road so fire trucks could reach reactor No 4 at theDaiichi complex in Fukushima, 240 km (150 miles) north of Tokyo. Flames were no longer visible at the building housing the reactor.
High radiation levels prevented a helicopter from flying to the site to drop water into the No. 3 reactor -- whose roof was damaged by an earlier explosion and where steam was seen rising earlier in the day -- to try to cool its fuel rods.
The plant operator described No 3 as the "priority". No more information was available, but that reactor is the only one at Daiichi which uses plutonium in its fuel mix.
According to US government research, plutonium is very toxic to humans and once absorbed in the bloodstream can linger for years in bone marrow or liver and can lead to cancer
The situation at No 4 reactor, where the fire broke out, was "not so good", the plant operator added, while water was being poured into reactors No 5 and 6, indicating the entire six-reactor facility was now at risk of overheating.
Nuclear experts said the solutions being proposed to quell radiation leaks at the complex were last-ditch efforts to stem what could well be remembered as one of the world's worst industrial disasters.
"This is a slow-moving nightmare," said Dr Thomas Neff, a physicist and uranium-industry analyst at the Massachusetts Institute of Technology.
Japanese Emperor Akihito, delivering a rare video message to his people, said he was deeply worried by the country's nuclear crisis which was "unprecedented in scale".
"I hope from the bottom of my heart that the people will, hand in hand, treat each other with compassion and overcome these difficult times," the emperor said.
Panic over the economic impact of last Friday's massive earthquake and tsunami knocked $620 billion off Japan's stock market over the first two days of this week, but the Nikkei index rebounded on Wednesday to end up 5.68 percent.
Nevertheless, estimates of losses to Japanese output from damage to buildings, production and consumer activity ranged from between 10 and 16 trillion yen ($125-$200 billion), up to one-and-a-half times the economic losses from the devastating 1995 Kobe earthquake.
Damage to Japan's manufacturing base and infrastructure is also threatening significant disruption to the global supply chain, particularly in the technology and auto sectors.
Scores of flights to Japan have been halted or rerouted and air travellers are avoiding Tokyo for fear of radiation. On Wednesday, both France and Australia urged their nationals in Japan to leave the country as authorities grappled with the world's most serious nuclear accident since the Chernobyldisaster in Ukraine in 1986.
In a demonstration of the qualms about nuclear power that the crisis has triggered around the globe, China announced that it was suspending approvals for planned plants and would launch a comprehensive safety check of facilities.
China has about two dozen reactors under construction and plans to increase nuclear electricity generation about seven-fold over the next 10 years.
In Japan, the plight of hundreds of thousands left homeless by the earthquake and devastating tsunami that followed worsened overnight following a cold snap that brought snow to some of the worst-affected areas.
While the death toll stands at around 4,000, more than 7,000 are listed as missing and the figure is expected to rise.
At the Fukushima plant, authorities have spent days desperately trying to prevent water which is designed to cool the radioactive cores of the reactors from evaporating, which would lead to overheating and possibly a dangerous meltdown.
Until the heightened alarm about No.3 reactor, concern had centred on damage to a part of the No.4 reactor building where spent rods were being stored in pools of water, and also to part of the No 2 reactor that helps to cool and trap the majority of cesium, iodine and strontium in its water.
Japanese officials said they were talking to the US military about possible help at the plant.
Concern has mounted that the skeleton crews dealing with the crisis might not be big enough or were exhausted after working for days since the earthquake damaged the facility. Authorities withdrew 750 workers on Tuesday, leaving only 50.
All those remaining were pulled out for almost an hour on Wednesday because radiation levels were too high, but they were later allowed to return.
Arnie Gundersen, a 39-year veteran of the nuclear industry who worked on reactor designs similar to Daiichi plant, said 50 or so people could not babysit six nuclear plants.
"That evacuation (of 750 workers) is a sign they may be throwing in the towel," Gundersen said.
RADIATION IN TOKYO NOT A THREAT TO HUMAN HEALTH
In the first hint of international frustration at the pace of updates from Japan, Yukiya Amano, director general of the International Atomic Energy Agency, said he wanted more timely and detailed information.
"We do not have all the details of the information so what we can do is limited," Amano told a news conference in Vienna. "I am trying to further improve the communication."
Several experts said the Japanese authorities were underplaying the severity of the incident, particularly on a scale called INES used to rank nuclear incidents. The Japanese have so far rated the accident a four on a one-to-seven scale, but that rating was issued on Saturday and since then the situation has worsened dramatically.
France's nuclear safety authority ASN said on Tuesday it should be classed as a level-six incident.
Officials in Tokyo said radiation in the capital was 10 times normal at one point but not a threat to human health in the sprawling high-tech city of 13 million people.
Many Tokyo residents stayed indoors. Public transport and the streets were as deserted as they would be on a public holiday, and many shops and offices were closed.
Winds over the plant were forecast to blow from the northwest during Wednesday, which would take radiation towards the Pacific Ocean.
"WHAT THE HELL IS GOING ON?"
Japanese media have became more critical of Kan's handling of the disaster and criticised the government and plant operator Tokyo Electric Power Co for their failure to provide enough information on the incident.
"This government is useless," Masako Kitajima, a Tokyo office worker in her 50s, said as radiation levels ticked up in the city.
Kan himself lambasted the operator for taking so long to inform his office about one of the blasts on Tuesday. A Kyodo news agency reporter quoted the prime minister demanding the power company executives: "What the hell is going on?".
Nuclear radiation is an especially sensitive issue for Japanese following the country's worst human catastrophe -- the US atomic bombs dropped on Hiroshima and Nagasaki in 1945.
The full extent of the destruction was slowly becoming clear as rescuers combed through the tsunami-torn region north of Tokyo where officials say at least 10,000 people were killed.
There have been hundreds of aftershocks and more than two dozen were greater than magnitude 6, the size of the earthquake that severely damaged Christchurch, New Zealand, last month.
About 850,000 households in the north were still without electricity in near-freezing weather, Tohuku Electric Power Co. said, and the government said at least 1.5 million households lack running water. Tens of thousands of people were missing.
In a sign of desperation, the police will try to cool spent nuclear fuel at one of the facility's reactors with water cannon, which is normally used to quell riots.
Early in the day another fire broke out at the earthquake-crippled facility, which has sent low levels of radiation wafting into Tokyo in the past 24 hours, triggering fear in the capital and international alarm.
Japan's government said radiation levels outside the plant's gates were stable but, in a sign of being overwhelmed, appealed to private companies to help deliver supplies to tens of thousands of people evacuated from around the complex.
"People would not be in immediate danger if they went outside with these levels. I want people to understand this," chief cabinet secretary Yukio Edano told a televised news conference, referring to people living outside a 30 km (18 miles) exclusion zone. Some 140,000 people inside the zone have been told to stay indoors.
Workers were trying to clear debris to build a road so fire trucks could reach reactor No 4 at theDaiichi complex in Fukushima, 240 km (150 miles) north of Tokyo. Flames were no longer visible at the building housing the reactor.
High radiation levels prevented a helicopter from flying to the site to drop water into the No. 3 reactor -- whose roof was damaged by an earlier explosion and where steam was seen rising earlier in the day -- to try to cool its fuel rods.
The plant operator described No 3 as the "priority". No more information was available, but that reactor is the only one at Daiichi which uses plutonium in its fuel mix.
According to US government research, plutonium is very toxic to humans and once absorbed in the bloodstream can linger for years in bone marrow or liver and can lead to cancer
The situation at No 4 reactor, where the fire broke out, was "not so good", the plant operator added, while water was being poured into reactors No 5 and 6, indicating the entire six-reactor facility was now at risk of overheating.
Nuclear experts said the solutions being proposed to quell radiation leaks at the complex were last-ditch efforts to stem what could well be remembered as one of the world's worst industrial disasters.
"This is a slow-moving nightmare," said Dr Thomas Neff, a physicist and uranium-industry analyst at the Massachusetts Institute of Technology.
Japanese Emperor Akihito, delivering a rare video message to his people, said he was deeply worried by the country's nuclear crisis which was "unprecedented in scale".
"I hope from the bottom of my heart that the people will, hand in hand, treat each other with compassion and overcome these difficult times," the emperor said.
Panic over the economic impact of last Friday's massive earthquake and tsunami knocked $620 billion off Japan's stock market over the first two days of this week, but the Nikkei index rebounded on Wednesday to end up 5.68 percent.
Nevertheless, estimates of losses to Japanese output from damage to buildings, production and consumer activity ranged from between 10 and 16 trillion yen ($125-$200 billion), up to one-and-a-half times the economic losses from the devastating 1995 Kobe earthquake.
Damage to Japan's manufacturing base and infrastructure is also threatening significant disruption to the global supply chain, particularly in the technology and auto sectors.
Scores of flights to Japan have been halted or rerouted and air travellers are avoiding Tokyo for fear of radiation. On Wednesday, both France and Australia urged their nationals in Japan to leave the country as authorities grappled with the world's most serious nuclear accident since the Chernobyldisaster in Ukraine in 1986.
In a demonstration of the qualms about nuclear power that the crisis has triggered around the globe, China announced that it was suspending approvals for planned plants and would launch a comprehensive safety check of facilities.
China has about two dozen reactors under construction and plans to increase nuclear electricity generation about seven-fold over the next 10 years.
In Japan, the plight of hundreds of thousands left homeless by the earthquake and devastating tsunami that followed worsened overnight following a cold snap that brought snow to some of the worst-affected areas.
While the death toll stands at around 4,000, more than 7,000 are listed as missing and the figure is expected to rise.
At the Fukushima plant, authorities have spent days desperately trying to prevent water which is designed to cool the radioactive cores of the reactors from evaporating, which would lead to overheating and possibly a dangerous meltdown.
Until the heightened alarm about No.3 reactor, concern had centred on damage to a part of the No.4 reactor building where spent rods were being stored in pools of water, and also to part of the No 2 reactor that helps to cool and trap the majority of cesium, iodine and strontium in its water.
Japanese officials said they were talking to the US military about possible help at the plant.
Concern has mounted that the skeleton crews dealing with the crisis might not be big enough or were exhausted after working for days since the earthquake damaged the facility. Authorities withdrew 750 workers on Tuesday, leaving only 50.
All those remaining were pulled out for almost an hour on Wednesday because radiation levels were too high, but they were later allowed to return.
Arnie Gundersen, a 39-year veteran of the nuclear industry who worked on reactor designs similar to Daiichi plant, said 50 or so people could not babysit six nuclear plants.
"That evacuation (of 750 workers) is a sign they may be throwing in the towel," Gundersen said.
RADIATION IN TOKYO NOT A THREAT TO HUMAN HEALTH
In the first hint of international frustration at the pace of updates from Japan, Yukiya Amano, director general of the International Atomic Energy Agency, said he wanted more timely and detailed information.
"We do not have all the details of the information so what we can do is limited," Amano told a news conference in Vienna. "I am trying to further improve the communication."
Several experts said the Japanese authorities were underplaying the severity of the incident, particularly on a scale called INES used to rank nuclear incidents. The Japanese have so far rated the accident a four on a one-to-seven scale, but that rating was issued on Saturday and since then the situation has worsened dramatically.
France's nuclear safety authority ASN said on Tuesday it should be classed as a level-six incident.
Officials in Tokyo said radiation in the capital was 10 times normal at one point but not a threat to human health in the sprawling high-tech city of 13 million people.
Many Tokyo residents stayed indoors. Public transport and the streets were as deserted as they would be on a public holiday, and many shops and offices were closed.
Winds over the plant were forecast to blow from the northwest during Wednesday, which would take radiation towards the Pacific Ocean.
"WHAT THE HELL IS GOING ON?"
Japanese media have became more critical of Kan's handling of the disaster and criticised the government and plant operator Tokyo Electric Power Co for their failure to provide enough information on the incident.
"This government is useless," Masako Kitajima, a Tokyo office worker in her 50s, said as radiation levels ticked up in the city.
Kan himself lambasted the operator for taking so long to inform his office about one of the blasts on Tuesday. A Kyodo news agency reporter quoted the prime minister demanding the power company executives: "What the hell is going on?".
Nuclear radiation is an especially sensitive issue for Japanese following the country's worst human catastrophe -- the US atomic bombs dropped on Hiroshima and Nagasaki in 1945.
The full extent of the destruction was slowly becoming clear as rescuers combed through the tsunami-torn region north of Tokyo where officials say at least 10,000 people were killed.
There have been hundreds of aftershocks and more than two dozen were greater than magnitude 6, the size of the earthquake that severely damaged Christchurch, New Zealand, last month.
About 850,000 households in the north were still without electricity in near-freezing weather, Tohuku Electric Power Co. said, and the government said at least 1.5 million households lack running water. Tens of thousands of people were missing.
Fraud Flying Licence: Another get Caught
NEW DELHI: A second Air India pilot has been found to have got his flying licence by allegedly submitting forged marks certificates and was grounded, making him the fifth pilot to be caught for using fraudulent means to procure a license.
The state-owned airline has desrostered the pilot, identified as Arjun Giare, pending enquiry for allegedly submitting a forged Class 10 certificate to show that he met the minimum age limit to become a pilot. The airline earlier suspended Capt JK Verma, who is under arrest, on similar charges.
The pilot, identified as Arjun Giare, "has been taken off duty pending enquiry. He is not flying now," a senior official of the national carrier said.
After the arrest of IndiGo pilot Capt Parminder Kaur Gulati on charges of producing fake marks card last week, the DGCA, while examining documents submitted by about 1,700 pilots to get licences in the past one year, detected that Capt Swaran Singh Talwar (MDLR) and Capt Meenakshi Singhal (IndiGo), besides Air India's Verma, had submitted forged result cards.
All these four cases are now being investigated by the police which has so far arrested Gulati and Verma. Police said Talwar and Singhal are "absconding".
Sources said that in November 2000, Giare's licence was cancelled by the US Federal Aviation Administration (FAA) on similar charges. He was also reportedly caught when he appeared for his Instrument Pilot Rating at the Fort Worth Aviation testing centre in the US.
The de-rostering of Giare came after the government ordered investigation into all pilot licences issued in the past and proposed to set up an expert committee to look into the current examination system.
Civil Aviation minister vayalar Ravi on Tuesday informed Parliament that he had asked Directorate General of Civil Aviation to examine all the licences issued in the past. Till date, about 4,500 Airline Transport Pilot Licences (ATPLs) have been issued.
Ravi also proposed to set up an expert committee in the Ministry to examine the current examination system, the need for introducing e-technology and new procedures and processes besides evolving an effective system of cross- verification of documents filed by candidates for various licences in DGCA.
The state-owned airline has desrostered the pilot, identified as Arjun Giare, pending enquiry for allegedly submitting a forged Class 10 certificate to show that he met the minimum age limit to become a pilot. The airline earlier suspended Capt JK Verma, who is under arrest, on similar charges.
The pilot, identified as Arjun Giare, "has been taken off duty pending enquiry. He is not flying now," a senior official of the national carrier said.
After the arrest of IndiGo pilot Capt Parminder Kaur Gulati on charges of producing fake marks card last week, the DGCA, while examining documents submitted by about 1,700 pilots to get licences in the past one year, detected that Capt Swaran Singh Talwar (MDLR) and Capt Meenakshi Singhal (IndiGo), besides Air India's Verma, had submitted forged result cards.
All these four cases are now being investigated by the police which has so far arrested Gulati and Verma. Police said Talwar and Singhal are "absconding".
Sources said that in November 2000, Giare's licence was cancelled by the US Federal Aviation Administration (FAA) on similar charges. He was also reportedly caught when he appeared for his Instrument Pilot Rating at the Fort Worth Aviation testing centre in the US.
The de-rostering of Giare came after the government ordered investigation into all pilot licences issued in the past and proposed to set up an expert committee to look into the current examination system.
Civil Aviation minister vayalar Ravi on Tuesday informed Parliament that he had asked Directorate General of Civil Aviation to examine all the licences issued in the past. Till date, about 4,500 Airline Transport Pilot Licences (ATPLs) have been issued.
Ravi also proposed to set up an expert committee in the Ministry to examine the current examination system, the need for introducing e-technology and new procedures and processes besides evolving an effective system of cross- verification of documents filed by candidates for various licences in DGCA.
How OS Works- Part 4
Processor Management
The heart of managing the processor comes down to two related issues:- Ensuring that each process and application receives enough of the processor's time to function properly
- Using as many processor cycles as possible for real work
The basic unit of software that the operating system deals with in scheduling the work done by the processor is either a process or a thread, depending on the operating system.
It's tempting to think of a process as an application, but that gives an incomplete picture of how processes relate to the operating system and hardware. The application you see (word processor, spreadsheet or game) is, indeed, a process, but that application may cause several other processes to begin, for tasks like communications with other devices or other computers. There are also numerous processes that run without giving you direct evidence that they ever exist. For example, Windows XP and UNIX can have dozens of background processes running to handle the network, memory management, disk management, virus checks and so on.
A process, then, is software that performs some action and can be controlled -- by a user, by other applications or by the operating system. It is processes, rather than applications, that the operating system controls and schedules for execution by the CPU. In a single-tasking system, the schedule is straightforward. The operating system allows the application to begin running, suspending the execution only long enough to deal with interrupts and user input.
Interrupts are special signals sent by hardware or software to the CPU. It's as if some part of the computer suddenly raised its hand to ask for the CPU's attention in a lively meeting. Sometimes the operating system will schedule the priority of processes so that interrupts are masked -- that is, the operating system will ignore the interrupts from some sources so that a particular job can be finished as quickly as possible. There are some interrupts (such as those from error conditions or problems with memory) that are so important that they can't be ignored. These non-maskable interrupts (NMIs) must be dealt with immediately, regardless of the other tasks at hand.
While interrupts add some complication to the execution of processes in a single-tasking system, the job of the operating system becomes much more complicated in a multi-tasking system. Now, the operating system must arrange the execution of applications so that you believe that there are several things happening at once. This is complicated because the CPU can only do one thing at a time. Today's multi-core processors and multi-processor machines can handle more work, but each processor core is still capable of managing one task at a time. In order to give the appearance of lots of things happening at the same time, the operating system has to switch between different processes thousands of times a second. Here's how it happens:
- A process occupies a certain amount of RAM. It also makes use of registers, stacks and queues within the CPU and operating-system memory space.
- When two processes are multi-tasking, the operating system allots a certain number of CPU execution cycles to one program.
- After that number of cycles, the operating system makes copies of all the registers, stacks and queues used by the processes, and notes the point at which the process paused in its execution.
- It then loads all the registers, stacks and queues used by the second process and allows it a certain number of CPU cycles.
- When those are complete, it makes copies of all the registers, stacks and queues used by the second program, and loads the first program.
How OS Works- Part 3
Operating System Functions
At the simplest level, an operating system does two things:- It manages the hardware and software resources of the system. In a desktop computer, these resources include such things as the processor, memory, disk space and more (On a cell phone, they include the keypad, the screen, the address book, the phone dialer, the battery and the network connection).
- It provides a stable, consistent way for applications to deal with the hardware without having to know all the details of the hardware.
The operating system controls every task your computer
carries out and manages
system resources.
Even if a particular computer is unique, an operating system can ensure that applications continue to run when hardware upgrades and updates occur. This is because the operating system -- not the application -- is charged with managing the hardware and the distribution of its resources. One of the challenges facing developers is keeping their operating systems flexible enough to run hardware from the thousands of vendors manufacturing computer equipment. Today's systems can accommodate thousands of different printers, disk drives and special peripherals in any possible combination.
How OS Works- Part 2
Not all computers have operating systems. The computer that controls the microwave oven in your kitchen, for example, doesn't need an operating system. It has one set of tasks to perform, very straightforward input to expect (a numbered keypad and a few pre-set buttons) and simple, never-changing hardware to control. For a computer like this, an operating system would be unnecessary baggage, driving up the development and manufacturing costs significantly and adding complexity where none is required. Instead, the computer in a microwave oven simply runs a single hard-wired program all the time.
For other devices, an operating system creates the ability to: - serve a variety of purposes
- interact with users in more complicated ways
- keep up with needs that change over time
In any device that has an operating system, there's usually a way to make changes to how the device works. This is far from a happy accident; one of the reasons operating systems are made out of portable code rather than permanent physical circuits is so that they can be changed or modified without having to scrap the whole device.
For a desktop computer user, this means you can add a new security update, system patch, new application or even an entirely new operating system rather than junk your computer and start again with a new one when you need to make a change. As long as you understand how an operating system works and how to get at it, in many cases you can change some of the ways it behaves. The same thing goes for your phone, too.
Regardless of what device an operating system runs, what exactly can it do?
How Operating System Works-Part 1
When you turn on your computer, it's nice to think that you're in control. There's the trusty computer mouse, which you can move anywhere on the screen, summoning up your music library or Internet browser at the slightest whim. Although it's easy to feel like a director in front of your desktop or laptop, there's a lot going on inside, and the real man behind the curtain handling the necessary tasks is the operating system.
Most desktop or laptop PCs come pre-loaded with Microsoft Windows. Macintosh computers come pre-loaded with Mac OS X. Many corporate servers use the Linux or UNIX operating systems. The operating system (OS) is the first thing loaded onto the computer -- without the operating system, a computer is useless.More recently, operating systems have started to pop up in smaller computers as well. If you like to tinker with electronic devices, you're probably pleased that operating systems can now be found on many of the devices we use every day, from cell phones to wireless access points. The computers used in these little devices have gotten so powerful that they can now actually run an operating system and applications. The computer in a typical modern cell phone is now more powerful than a desktop computer from 20 years ago, so this progression makes sense and is a natural development.
The purpose of an operating system is to organize and control hardware and software so that the device it lives in behaves in a flexible but predictable way. In this article, we'll tell you what a piece of software must do to be called an operating system, show you how the operating system in your desktop computer worksPotasium Iodide is the Anti dote to prevent the effects caused by the Nuclear radiations.
But unwanted or Unnecessary use of Pottasium Iodide would expose themselves to other medical problems by needlessly taking it in the hope of protection from cancer
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