Rex A. Hoover

5263 Stewart Road

Sumerduck, Virginia, 22742

540-439-3690

rex@tritekcorp.com

United States Navy

August 1959 — May 1968

Rex A. Hoover

USN August 1959 — May 1968

Shortly after reaching 17 years of age I decided to take the advice of the juvenile court judge and my

probation officer and join a branch of the Armed Services. I lived in Akron Ohio and was a married

high school dropout with a juvenile record and a dismal outlook for any kind of reasonable future.

So soon after my older brother’s high school graduation, he and I went to the office of the Marine Corp

Recruiter to enlist. The Recruiter told me that the Marine Corp did not accept married people. They

did take my brother.

A bit discouraged, I went to the Air Force Recruiter and was told the Air Force would not accept people

with juvenile records. Further discouraged, I went to the Army recruiter and was told being married

was acceptable, and having a juvenile record was acceptable, but not both!

Totally discouraged, I went home and called the Navy recruiter on the phone and said, “ I’m a 17 year

old married high-school drop-out with a juvenile record, can I join the Navy?” He said “Sure son, come

on down”.

It turned out that being limited to the Navy was absolutely the best thing that could ever have happened

to me. By the time I finished my 9-years in the Navy I had built the foundation for a meaningful life

that I would relish for many decades to come. And to this day, I look back on those 9 years in uniform

with great pride.

In August 1959, I took the bus to the Great Lakes Naval Training Station outside of Chicago, Illinois

and was inducted into the United States Navy, 3 months after my 17th birthday. My first realization

that my world had really changed was when I sat down in the barber's chair, and was asked how I would

like my '50's era DA hairdo cut. DA is short for Duck’s Ass, a hair style that was in vogue at that time

for all rowdy teenagers where the two long sides of hair were greased and swept backward on the head

like two bird wings held at the side. In the time it took me to comprehend the question and begin to

form a response, my hair was gone! And the barber was saying "next" with a grin on his face that

went from ear to ear. I got out of the chair with a scalp capable of sensing the surrounding air

temperature, something that had not been possible for years.

At Boot Camp I was part of an 80-man crew in Company 401. After

the Navy shaved our heads, they gave us lots of inoculations, taught us

how to wash our clothes, fight fires, and get comfortable in a room

filled with tear gas. This was also my introduction to things I had

never tasted before, like real butter, steak, and those famous, or is it

infamous, Navy instant potatoes.

Scrubbing the ring out of my "White Hat" in the hand washing

facilities.

From there it was off to southern California where I became a member of the Pacific Seabees and

attended Construction Electricians "A" School at Port Hueneme. We studied basic electricity,

motor/generator design & repair, telephone system maintenance, industrial building wiring and power

line installation and maintenance.

Graduating first in my class entitled me to my choice of available duty stations. Of course, in the Navy

there was always a catch, and in this case it was that the only available duty station was with Mobile

Construction Battalion #10, which was currently deployed on Guam, an island just north of the equator,

in the middle of the Pacific Ocean.

I became a member of MCB 10, a battalion of about 600 construction workers deployed to Guam for 9

months to pave roads, build houses for military personnel, and erect large buildings for things like

rigging parachutes. When we weren't busy building things, we went into the jungle to play war games.

On Sundays, many of us toured the island that is 26 miles long and 4 to 8 miles wide, stopping often to

go free diving in the coral reefs. What I saw under the water was well beyond anything I had ever seen

or even imagined. Fantastic doesn't begin to describe those coral reefs and all the sea life there. In

fact, on my first excursion under the sea, what I saw actually made me gasp, which is definitely not a

good thing to do under water. After almost drowning, I cleared my lungs and made certain I would

not do that again!

1960 — Guam, M.I. Japanese 2-Man Submarine from WWII

Umatac Bay from Megellan's Landing Village of Umatac

Latte Stones - Pillars upon which Prison Cells built by Japanese Army

Chamorros built their homes during WW II occupation

A water buffalo we met in the jungle Flame Tree at Talofo

while out exploring.

Then it was a 5500 mile trip on the USNS Barrett back to Port Hueneme, California.

On 15 March, 1961, it was off to Adak, Alaska on board the troop ship USS Mann. The Main Body was

dropped of at Kodiak Island, while the group I was in (Detachment Charlie) continued out the Aleutian

Island chain to Adak. I spent this tour working out of the electrical shop doing a variety of things like

splicing lead-covered cable, and in my free time, operating the radio so our guys could to talk to their

loved ones at home. Our call sign was KL7AZN

The greatest distinction Adak had was that the soil could not support trees. The Adak National Forest

was a small group of evergreens planted during World War II that I could look over the top of.

However, in the spring the tundra would come alive with flowering plants and looked like one very large

flower garden.

Collins Amateur radio gear — 1961

Naval Nuclear Power Unit

I was 19 years old spending many of my working days inside a leaky tent set up over a wet ditch. I was

in that ditch splicing lead-covered cable mistakenly dug up by my Equipment Operator brethren. The

reason I mention the leaky tent is that I was making splices in cables using the old technique of a solder

pot and wiping the joint. Now solder and water are mutually exclusive, that is they can not occupy the

same space. So when water drops into a solder pot, anyone nearby ends up wearing hot lead. As I did

that work, I concluded that volunteering for the Navy's Shore Based Nuclear Power Program was a great

idea.

What they neglected to tell us "volunteers" is that I would have to spend 12 winter weeks in Great Lakes

Illinois taking a Basic Electronics Course, and then 52 weeks in a grueling test of endurance attending

the Nuclear Power Plant Operators Course at Fort Belvoir — all to get ready to spend 14 months at the

bottom of the planet where a heat-wave is -10ºF and the wind can actually blow you away. You see,

the Navy, in its infinite wisdom, chose to put their Nuclear Power Plant in Antarctica instead of Hawaii.

What were they thinking?

My introduction to the Naval Nuclear Power Unit was at Great Lakes Illinois. I attended a 12-week

course of instruction on basic electronics and special circuits, graduating 2nd in class of 10.

Then it was off to Fort Belvoir Virginia to attend the Army’s Nuclear Power Plant Operators Course.

Decades after attending the course, I received a telephone call from the Senior Chief who was on the

student selection committee. He asked if I had ever wondered why I was selected for the course. I said

yes, I had always assumed it was an error. I had volunteered for the course but was told that they would

not accept high school drop-outs, especially one who dropped out in the 10th

grade.

The chief told me that I was selected as an “experiment”. The selection committee wanted to see how

far a person with a high IQ and no formal education could get. They even had a pool and not one

person actually picked me to finish the college-level academic phase. I sincerely hope that the fact that

I finished the academic phase 4th

out of a class of 24 convinced them that the quality of the education

program that they were a part of was beyond outstanding.

Nuclear Power Plant Operators Course — 52 weeks of blood, sweat and tears.

76 hours of mathematics (trigonometry, algebra, logarithms).

55 hours of classic and modern physics.

64 hours of nuclear reactor engineering.

59 hours of electrical engineering.

72 hours of mechanical engineering.

46 hours of health physics and process control.

125 hours of electronics and solid-state devices.

133 hours of nuclear instruments.

278 hours of process and nuclear research instruments.

718 hours of instruction and on-the-job training operating the SM-1 Army Nuclear Power Plant.

The SM-1 Nuclear Power Plant at Fort Belvoir, Virginia

NPPOC Class 62-1 Graduation

TRANSCRIPT OF COMMENTS MADE BY RADM N.J. DRUSTRUP, CEC, USN, DEPUTY CHIEF

OF CIVIL ENGINEERS TAKEN FROM THE 28 MARCH 1963 CIVIL ENGINEER CORPS

WEEKLY REPORT AFTER HIS ADDRESS TO THE 62/1 GRADUATING CLASS OF MARCH

1963.

It was my pleasure last Monday to address the graduating class of the Nuclear Power Plant

Operators Course at Fort Belvoir, Virginia. This course is a tri-Service program, under the cognizance

of the Army, with both the Navy Unit and the Air Force Unit providing instructors. LCDR Neal W.

Clements is the Deputy Officer in Charge, and seven more of our COC officers are on duty there.

In addition to training operators, the Navy Unit provides field technical services for the Bureau,

and administers the Navy personnel assigned to operate and maintain the Navy's shore based nuclear

power plants. Also, they keep abreast of the development of nuclear power as applicable to Navy

shore activities.

The Plant Operators Course lasts for one year, and this year's class was attended by 17 Navy men

and 5 Army men. These men deserve the highest praise for having completed this difficult course

satisfactorily. It is one that demands a maximum degree of application, concentration and persistence.

It involves fundamentals in several disciplines of engineering — nuclear, mechanical, electrical,

electronics and chemistry. Consequently, their classroom work has been long and demanding. And, in

addition, they were given the job training in the operations of a nuclear power plant.

These men illustrate the quiet kind of patriotism that is just as necessary to our national welfare

as direct military action. This is the patriotism of unstinting application to the job at hand; a spirit of

cooperation; obedience to the rules of the organization; and the utmost use of native talents so that the

individual may contribute to the general cause to the fullest extent of his ability. This dedicated

devotion to duty is the foundation upon which a successful military organization must be built.

Incidentally, the diplomas our men received at the graduation were accompanied by certificates

to their wives, in appreciation of their patience and understanding and the sacrifices they are making

towards their husband's successes.

/s/ N. J. DRUSTRUP

Rear Admiral, CEC, USN

Deputy Chief of Civil Engineers

More Training — Leonard "Mac" McGregor

explaining why it takes so many knobs, levers, and

gauges to get electricity from a couple of neutrons and

a tiny spec of uranium

….and a little fun

The Question:

How long can a nuke stay attached to a pole?

The answer:

As long as it takes to get the job done.

Embarrassing Demo

I volunteered to teach some soldiers how to climb

poles in a combat setting. They were headed to Viet

Nam and needed to be able to get off a pole quickly

and safely.

To demonstrate the technique called “combat jumps”,

I would go up the 40 foot pole, and then race down the

pole at nearly the same speed as jumping from it,

slowing the descent just before reaching the bottom.

This entails taking giant steps and a lot of balance

control.

The day I was to demonstrate the technique, there were spectators in several windows of the nearby

building as I ran up the pole to get ready for the rapid descent.

About half way down the pole one of my hooks got stuck in a knot just long enough to destroy my

balance and I fell the rest of the way landing flat on my back in the grass. When I hit the ground I

expelled air from my lungs that I am sure had been in there for years! And the crotch of my trousers

was ripped open from knee to knee.

As nonchalant as I could I said, “Now that is the way NOT to do it” and proceeded up the pole again

looking carefully at the pole surface to see what had hung my hook. I redid the demo successfully the

second time and then went in and changed my trousers.

Then More Training — PM-1 Nuclear Power Plant and 3 Radar Domes at Sundance Wyoming

I attended PM-3A Crew training with Crew III, in preparation for a tour at the PM-1

My tour at the PM-1 was followed by a summer tour at the PM-3A with Crew IV. Then it was a

winter-over tour with Crew V.

A short flight to Christ Church, New Zealand for transport to the ice on a C-130 Hercules

A little flight over Antarctica

And then it's McMurdo Sound Antarctica and the PM-3A Nuclear Power Plant

with Crew V Nukey Poo's

Lt T.L. Boennighausen LtJG J.W. King M.E. Adams R.J. Moffat J.E. Ray R.T. Plichta

J.P. Fleming J.E. Robertson R.J Whiteman H.L. Persell G.V. O'Connor E.H. Hoffmann R.B. Hair

C.E. Reed M.E. Ramsey S. Brown E.F. Funkhouser J.W. Gannon D.L. Andrews D.J Perotti

R. J. Robinson R.A. Hoover R.F. Anderson M.H. Bell

Our Ground Transportation — the Blue Goose

The Summer Maintenance Support Crew — Now there's a group that any mother would be

proud to claim belonged to someone else.

Les Page Ed Groover Jack Ashenden Leonard McGregor

But don't let appearances fool you; these guys were really good at that stuff!!

The best looking guys lived in Hut 14; the ugly ones all went to the "Chiefs Quarters".

Plichta Robson

Purcell Andrews

Hair Hoover

Perrotti Anderson Funkhouser Adams

Hut 14 Winter-Over White Hats

Hut 14 — The Grand Tour

Bar & Lounge Game Room

Entertainment Center Hallway

Urinal – Trough to 55 gal drum Hoover's Room

And of course there was always time to work

My Nemesis — the Multi-Channel Analyzer. I added 42 cuss words to my vocabulary before I got

this damn thing working again.

Of all the things I have done in my

more than half a century of working

in the technical arena, this was

certainly one of the most

challenging.

The nuclear power plant effluent

must be analyzed every day using

this instrument.

After several years of service, the

instrument failed and there was no

backup. McMurdo was isolated

with no traffic in or out for 9

months. Not fixing it meant

shutting the power plant down for

the entire time, which was highly

undesirable.

This meant that I had to take out the schematics for what was a digital computer with hardware

programming that I had no training on, figure out how it worked, and then find and replace all the failed

parts. I had 24 hours to do it after having already worked most of a 10-hour day.

I located and replaced several failed components and had the instrument working a couple of hours

before the deadline. It was a very long and very stressful work-day!!!

and then I celebrated

For R & R, Dale Andrews & I went out with the Kiwi's (New Zealanders) and their dog team

(When they could keep the dogs from killing each other that is).

We went to the Ice Caves

And we validated that old axiom "the view never changes unless you're the Lead Dog".

I kept this picture because it reminded me so much of B and K.

We really appreciated the guys who kept the

channel free of ice so the booze and steak

could be delivered. (It took a lot of both to

get us through the long winter night). May

God bless them, every one.

During the summer, we took a little time off to play with our friends

Partying with the icebreaker crew. — Those boys had a hard time keeping their Brandy

Alexanders in their stomachs and off the snow.

But we fed them lots of steak to go with all that dessert.

The Sled Ride

This is the "bobsled" engineered by McGregor and Schloredt. The group of us (Jerry Schloredt,

Leonard McGregor, Rex Hoover, Russ Anderson, Jack Ashenden) took this thing on a ride down a

glacier one afternoon and it was a once in a lifetime experience. I say once because even we weren't

dumb enough to do it a second time. This is what happened, as I remembered it some 4 decades later.

With Jerry as our guide, we dragged the sled up a road and over what seemed like miles of packed snow

to reach the top of a small mountain. On the way we passed the McMurdo doctor and dentist, out in

their truck on a routine medical run. We stopped to chat, and then continued up the mountain while the

doctors continued down. It was a bright sunny day with the temperature cold enough to freeze the

beer, and put ice crystals in the Scotch, we were carrying. We eventually reached the top where all we

could see was a downhill slope that disappeared from view after a distance of about 1/2 mile. Jerry

explained that we needed to travel downhill with constant steering to the right or we would end up going

off a hundred foot high cliff at the bottom edge of the glacier. With appropriate fortification of our

resolve from the little bit of unfrozen booze in our pockets, we climbed on the "bobsled" and promptly

descended the mountain at what felt like the same speed we would achieve jumping out of a 40-story

building. About the time we crested the first and shallowest part of the mountain slope, we lost two of

our riders. The three remaining continued with Mac in front, Jerry behind Mac, and me on the brakes at

the rear. When we went over that crest, our speed increased significantly and Jerry yelled "put on the

brakes". I yelled back "I got them on". It seems that the two pipes Mac and Jerry designed for brakes

actually made the sled go faster when put into position. That is the second time I knew we were not

operating in a method consistent with good mental health, the first being when we got on the damn sled

in the first place!

So down the side of this glacier we went, at a speed that no human being should reach without being

surrounded by a motorized vehicle of some kind. After what seemed like at least a mile of travel, Mac

began yelling "Get off the sled". What you have to envision when you read this is that the temperature

was well below zero, it was a bright sunny day on the side of a huge white glacier, we were traveling

very fast, and only Mac had goggles! Squinting into the bright light with a cold wind in your face and

no goggles means tears, not clear vision, so Jerry and I couldn't really see what was happening. We

assumed Mac was concerned about going over the cliff at the bottom, so our well considered response

was "no, we're riding it to the bottom". After Mac repeated his plea several times we decided to honor

his request and ended up crashing into a wall of snow. It seems Mac and Jerry's sled design didn't allow

for departure while in motion.

It was then that we found out that Mac's leg had slipped under the runner and we were bouncing down

the side of the glacier riding on his ankle! Mac insisted on walking back to Hut 14 without aid, and of

course we went along since he can be just a tad stubborn. When we got back to Hut 14 and pulled his

boot off, Mac's ankle puffed up in the most gorgeous shades of red, purple and green, much like a

Hawaiian sunset.

I assume that the rapid swelling and colorful appearance of his leg prompted Mac to change his mind

about accepting a little help from his friends, because he allowed us to half carry him to sickbay. So

here are the same guys the doctor saw several hours ago dragging a sled up the side of a mountain, now

dragging one of their group into sickbay with a nasty looking ankle. When the doctor asked what

happened, we explained that we were having a party in Hut 14 (which was a common occurrence) and

Mac twisted his ankle while "stomp dancing". The doctor, with a grin on his face and a twinkle in his

eye, filled out the medical form accordingly. The next day the base commander had a notice posted

that we had to tone down our parties since they had gotten so active that someone got seriously hurt.

There were 110 men on the base, 109 knew what happened. Can you guess which one didn't?

I had the opportunity to see that glacier from a helicopter later and it was a good thing I didn't see it

before the ride. There was not enough "idiot water" on the ice to get me to do something that crazy with

the full understanding of what I was doing. But it did reinforce my resolve to seriously question any

further requests from Jerry to join another of his adventures.

As the word spread of our little ride, the Kiwi's at Scott Base were so impressed that they gave us a party

to celebrate our adventure, and present us with Scott Base Ski Club patches.

And the best part, Mac lost his limp after only a few years.

The Saga of the Blue Goose On a day in the middle of the winter season, I was asked to take

some documents down town to the personnel office. I started up

the Blue Goose and noticed that the emergency brake had been

set--something that shouldn’t have been done in this cold temp as

the brake might freeze. I undid the brake and headed downtown.

Noticing the Goose was low on fuel, my first stop was the

refueling station. I stopped the truck and shut off the engine.

When I got out of the truck, I saw smoke coming from the

emergency brake area under the truck. I threw some snow on it

to make sure no fire started and refueled.

From there I drove to the personnel building where I stopped the

truck in front with the engine still running, and quickly ran inside

to drop off the documents. I have no idea why I did not shut

off the truck and leave it in gear, but I didn't. I rationalized it later that I could not use the emergency

brake and the ground did look flat but I have to admit, this was one of the top 5 dumbest things I have

ever done, and I don't remember the other 4.

Anyway, I popped into the office and came right back out only to see the Blue Goose bouncing down

the road headed for the ice. I could see her clearly with the two bright beams of light coming out the

front as she passed a pickup truck coming up the hill. As I was running at top speed to "catch" the

Goose I heard the pickup driver shout "Who the bleep is driving that bleeping truck". As I ran past

them I yelled, "I am". My only regret is that I could not see the face of the pickup driver as he heard

those words.

Soon thereafter the Goose left the road and got high-centered in the snow on the right shoulder of the

road, engine still running. I jumped in and tried to drive out of the snow bank but that just wasn't gonna

happen.

I had to hike my 'feeling-stupid' butt to the motor pool and ask for someone to pull me out of the snow

bank. After they got done rolling on the floor laughing, I got a volunteer.... and it only cost me a case of

beer and hearing "Hey Hoover, where'd you park the truck" for many weeks thereafter.

We could visit the scientists that thought it was OK to bore a hole in 6 foot thick ice and swim with

the seals & fishes. It seems that there is more sea life per cubic meter in the Antarctic Ocean than

any other ocean on our planet. And who says God doesn’t have a sense of humor?

We could visit the pressure ridges where the new Or we could visit with some of the

ice (6’ thick) meets the old ice (1 mile thick). indigenous population: 18” tall

Those ridges are about 20’ tall. Adelie penguins…cuddly looking little

critters with feet like a bear and a

preference for their own company.

Or we could visit with the seals. One scientific study that really needs to be done is how seal

excrement can smell so bad. Just the vapor from that stuff can peel the paint off a bulldozer.

There was always fine dining available at Scott’s Hut. Biscuits made around 1904.

We could just go sight-seeing…….

The view across the ice Downtown

The distant mountain range View of town from the sea

Town from afar PM-3A from town

And then there was always time for more work

The Winter-Over maintenance crew — on these 5 sets of broad shoulders rested the health and

well being of a $6,000,000 Nuclear Power Plant. Now how in the world could you not trust such a

distinguished group of gentlemen with that awesome responsibility?

Funkhouser — Ramsey — Hoover — Fleming — Hoffmann

And more time to relax

The maintenance crew's weekly formal dinner with invited guests from town. (Another of John

Fleming’s inspirations).

The Crew V Operations Team worked too, and they did good (with a little help from the Summer

& Winter-Over Maintenance crews of course).

MR NR187/12

RR RUHPMA

DE RUECG 478 2841340

ZNR UUUUU

R 111340Z OCT 66

FM NAVFACENGCOM

TO RUHPMA/NAVNUPWRU DET MCMURDO

INFO RUECW/CNO OP-07, OP-075

RUECYG/COMNAVSUPFOR ANT

RUEGPM/COMANTARCTICSUPACTY

RUEOFUA/NAVNUPWRU FT BELVOIR

RUCKHC/CINCLANTFLT

RUEGPM/COMCBLANT

BT

UNCLAS

PM-3A DETECHMENT CREW V COMMENDATION

1. FOR LT THOMAS L. BOENNINGHAUSEN; I TAKE PLEASURE AND PRIDE

IN COMMENDING YOU AND THE MEMBERS OF CREW V ON THE ESTABLISHMENT

OF A NEW RECORD FOR CONTINUOUS POWER OPERATION FOR MILITARY REACTORS.

THE NEW RECORD OF 3390.4 HOURS WHICH SURPASSES THE PREVIOUS RECORD

OF 3355.5 HOURS IS A TRIBUTE TO YOUR PERFORMANCE AND EFFECTIVENESS

THROUGHOUT THE LONG ANTARCTIC WINTER NIGHT. AS YOU PREPARE TO TURN

THE PLANT OVER TO CREW VI IT GIVES ME GREAT SATISFACTION TO

CONGRATULATE YOU AND YOUR CREW ON YOUR PERFORMANCE WHICH IS IN

ACCORDANCE WITH THE HIGHEST TRADITION OF THE NAVAL SERVICE.

RADM W. M. ENGER, ACTING CHIEF OF CIVIL ENGINEERS, SENDS.

BT

TOR: 0106Z 12 OCT 66 ///DG

COPY

The 200 Club

Crew V members founded the 200 Club — All you

had to do to join was subject your body to a 200

degree temperature differential.

You set the steam bath to 140 degrees and went

outside, wearing everything you were born with,

when the temperature was -60 degrees, and

remained outside for 60 seconds.

In 1966 there were three members, John Fleming,

Rex Hoover, and Bob Robson.

John Fleming coming out of his invention-the

world’s first Nuclear Powered Sauna.

John Fleming Rex Hoover

The towels are for the appearance of modesty — at 60 degrees below zero, the part of the male body

that modesty demands be hidden, was already hidden by the cold.

We did not have to dream of a White Christmas — our "white" averaged 1 mile deep.

It was a very long way to go for a meal, but it was good!!! (not that good though)

Some more scenery from our back yard from when the hours of daylight were getting very short

The Town from the rear of the Maintenance Building Erebus — The Gateway to the Underworld

The Cross Overlooking PM-3A Our Lady of the Snows

When you're living at the bottom of the planet, where the night is 4 months long, the temperature is cold

enough to freeze beer, and the wind cuts you like a frozen knife, it's good to have friends in high places.

...and for spending all that time at the bottom of the planet, they gave us a medal.

McMurdo at Night under a Full Moon

After my tour at McMurdo, I returned to Fort Belvoir as an instructor for follow-on crews heading to the

PM-3A. I completed my Navy career in May of 1968, on my 26th birthday after 9 years of service.

I built a rewarding career based on the education and experience I received while in the U.S. Navy.

After receiving my Honorable Discharge, I had a very successful 25 year career with IBM. I started as

an electronics technician and rose through the ranks to be a senior engineer and laboratory manager. I

published papers at international symposia on Scanning Electron Microscopy, Very Large Scale

Integrated Circuit Design, and Laboratory Management.

In 1993 I left IBM to join my wife and son in the founding of a company (TriTek Corp.) to design,

manufacture, and market personal-computer based video microscopes.

By the time I semi-retired in April 2014, we had eight patents on our designs, and had developed and

delivered 20 unique product models, with some models selling as many as 30 each. We had distributors

in England, Japan, Australia, India and the United States. TriTek’s products are installed in 17

countries around the world.

MORPHΣUS SnapDragon High-resolution optical microscope Optical zoom microscope

AutoComet CrystalPro DNA damage measurement Protein crystal analysis

Icarus PC-MAT Radioactive element inspection Material micro-alignment