45: Chapter 45 When You Write Down a Number

Ever since those few replies regarding experiments, reloading, and fitting, the two of them had chatted successively several more times.

After seemingly confirming something, Professor Lu Zhixing's tone increasingly treated him like a student.

This made Jiang Lin feel a bit guilty, because he was far too clear about how his meager foundation had actually come to be.

"I've thought about it for a long time and decided to ask you: If you truly want to start from the basics to make up for the underlying logic of measurement and experimentation, and can manage to calm your mind and prepare yourself to endure hardship, you can go read two books."

"The first: John Taylor's "Introduction to Error Analysis"."

"It doesn't teach high-end, sophisticated instruments; it only teaches you one thing: when you write down a number, just how much you actually believe in it. For the other book, look for textbooks or handouts in the direction of Digital Image Correlation / DIC, focusing on calibration, distortion correction, and the conversion from pixel coordinates to physical coordinates. The question you asked last time about how to turn a photograph into a repeatable coordinate system—the answer is right here."

"This book is the hidden prerequisite course for college Physics experiments. Many schools recommend it as supplementary reading to freshmen, but undergraduates often still don't understand it by their junior year because they have never personally disassembled and rebuilt a testing apparatus with their own hands."

"The second: Liang Jinwen's "Digital Speckle Correlation Methods and Experimental Mechanics"."

"This book talks about a non-contact measurement method. When you don't have high-precision displacement sensors, laser interferometers, or extensometers, and only have a few lamps, a few fixing bolts, and an ordinary camera, how can you rely on the changes within the images themselves to measure the displacement and deformation of an object."

"You might feel Chapter 1 is distant, and Chapter 2 difficult, but by Chapter 5, you will see it discussing how to correct the distortion of optical systems, how to calibrate cameras, and how to connect pixel coordinates with physical coordinates. This is precisely the core question you figured out on your own last time: how to make a single photograph provide a set of repeatable coordinate systems."

"If you only want to score high on exams, these two books cannot help you. If you only want to use ready-made equipment to run a standard experiment and then write it up in a report to submit, they cannot help you either. But if you want to know just how credible a number is, want to know why experiments are harder than theory, why measurements are never perfect, and why people who do experiments are always more silent than those who do theory, these two books will tell you."

"If you truly chew through these two books and perform the calibration processes, error verification, and repeatability tests inside them yourself, you won't just be a student who knows how to blindly apply formulas; you will directly gain the training in hands-on work that most undergraduates lack."

...

The first batch: books and materials.

He placed orders on Pinduoduo for "Introduction to Error Analysis", "Digital Speckle Correlation Methods and Experimental Mechanics", "Basics of Fitting", "Metalworking Practice Tutorial", "Mechanical Drawing", "Basics of Interchangeability and Measurement Technology", "Basics of Electronic and Electrical Technology"...

All of them were second-hand; he saved wherever he could.

He also went to the print shop next to the school to print out physical copies of several English Physics experimental handouts and machining manuals he found online.

...

Because he scored first place in the city-wide mock exams, this Spring Festival was a bumper harvest for red envelopes; whenever relatives met him, none failed to give a large red envelope.

Throughout the entire New Year period, he almost collected nearly twenty thousand yuan.

It was more than all the previous seventeen years of his life combined.

However, this time he needed to rebuild a more complex power and measurement system, so even with nearly twenty thousand yuan, he still had to split every single penny in half to spend it.

For instance, camping out on Xianyu for well-conditioned second-hand precision flat-nose pliers.

By the time all the purchases were completed, the time had reached mid-February.

The second semester of high school senior year had begun.

The Gaokao countdown in the upper right corner of the blackboard had been changed by the duty student with bright red chalk to a startling 113 days.

The entire senior building was like an old boiler operating under overload, and even the air seemed to float with irritating sparks that made people anxious.

"Students, over a hundred days sounds quite long, but calculate it yourselves—subtracting sleep, eating, going to the restroom, dazing off, and losing focus, how many hours are left?"

On the podium, head teacher Lao Liu banged the desk loudly with a blackboard eraser.

Today, he deliberately wore a brand-new red sweater, which was reportedly specially picked out and bought by his wife at the shopping mall to bring good luck to him, the head teacher of the prospective city-wide number one student.

This sweater looked a bit awkward worn on Lao Liu.

He usually always wore a dark gray coat, black trousers, and old leather shoes; the whole person was like a draft paper written with too much text.

Today, suddenly glowing bright red instead made many people in the class unable to resist stealing several glances.

Yet Lao Liu remained completely oblivious.

His mind was filled entirely with the Gaokao.

"Doing one more question now can wipe out a thousand people in the examination hall."

...

Seatmate Sun Ming was biting his pen cap while catching up on his winter vacation homework, scratching his ears and cheeks in frustration over a major electromagnetic field question on a Physics test paper.

"A charged particle undergoes uniform circular motion in a uniform magnetic field... The Lorentz force provides the centripetal force... That's not right, how come this radius calculates out to be a negative number? Is this question poisonous or what?"

Sun Ming was as anxious as an ant on a hot pan and habitually glanced sideways.

Jiang Lin was sitting there leisurely spinning his pen.

A grid notebook was spread out on his desk.

Sun Ming had originally just glanced at it casually.

A complex three-dimensional structural diagram was drawn on the grid notebook.

Several tangents and normals crisscrossed, marked with various Greek letters and dense data, alongside a few lines of derivation that looked like calculus or some kind of material mechanics formula.

"Holy crap, Brother Lin," Sun Ming lowered his voice, his tone carrying a sense of awe as if looking at an alien, "what kind of immortal problem are you calculating here? Are there such problems on our test papers? How does this look like a cross-section of an engine?"

Jiang Lin shook his head.

What was drawn in the notebook was, of course, not some science exam problem.

Instead, it was a homemade yaw bearing sketch for a miniature wind turbine.

For his fifth Wasteland seclusion, he estimated the duration would be at least no less than forty years. In terms of energy, relying solely on solar panels would definitely fall far short.

The wind season in the Wasteland World was long and violent; he had to make use of it.

But in that wilderness, he couldn't buy a finished wind turbine, and even if he could, once the precision components inside were damaged, they could not be repaired.

He wanted to try and see if he could piece together an inefficient yet maintainable yaw system using scrap car wheel hubs, ordinary bearings, steel plate flanges, and hand-processed limit structures.

As long as he could survive in the sandstorm, take it apart, repair it, and use it for ten or twenty years, that would already be enough.

"Consider it a bit of an extension of Physics." Jiang Lin turned the page of the grid notebook without changing his expression and replied in a calm tone.

Sun Ming sighed, his eyes full of despair after being hit by dimensional reduction.

"You're already first in the city, yet you're still working this hard. I can't even figure out a simple Lorentz force; why is the gap between people so huge?"

Jiang Lin didn't take up the conversation, his gaze falling back onto the paper surface.

Lao Liu gave a hoarse mobilization speech on the podium, and "Fight for a hundred days, change your destiny" was written on the blackboard.

All of these were reminding him of a timeline.

The Gaokao, the most important exit in an eighteen-year-old's life.

Yet another timeline lay horizontally across Jiang Lin's mind.

[Distance to the fifth Wasteland teleportation: 18 days]

[Estimated stay duration: 40 years or more]

The class bell rang.

Instead of delaying the class as usual, Lao Liu quickly packed up the podium. Before leaving the door, he waved in Jiang Lin's direction: "Jiang Lin, come to my office for a moment."

Several envious gazes were immediately cast from the corridor.

In No. 7 High School, being called alone to Lao Liu's office usually meant two things.

Either one had committed a heinous crime and would be scolded fiercely, or one was going to receive special tutoring as a core seedling.

For Jiang Lin, who had just won first place in the city, it was obviously the latter.

Jiang Lin closed the grid notebook, stuffed it into his pocket, and followed Lao Liu into the grade group office.

Lao Liu walked over to his desk piled high with teaching assistant materials, pulled open the drawer, first took out a thermos cup to drink a sip of wolfberry water, and then felt out a form from the very bottom, pushing it in front of Jiang Lin.

"Sit, don't just stand there."

Lao Liu pointed to the folding round stool nearby, the seriousness on his face instantly melting into the kindness of an elderly father, even the crow's feet at the corners of his eyes exuding joy.

Jiang Lin sat down accordingly, his gaze sweeping across that form.

[Tracking Form for Jiangcheng City's Senior High School Outstanding Graduates Special Training Plan].

"This is a directory put together by the municipal education bureau side, and you are the only one from our school to get in. First place in the city-wide mock exam, the gold content is just too high. The principal has spoken: from now until the Gaokao, you are No. 7 High School's Class A protected animal."

There was a barely suppressed pride in Old Liu's tone.

"Jiang Lin, Teacher knows you're a child with your own ideas. In these last hundred days, whatever requests you have, feel free to make them. If you think the classroom is too noisy, Teacher can separately apply for an empty classroom in the Academic Affairs Office for you to study by yourself. If you feel there's no need to write homework for certain subjects and want to arrange your own pace, you can also say so directly..."

Hearing these words, Jiang Lin's heart suddenly stirred.

He was just worrying about how to solve the upcoming heavy material transfer problem.

He had ordered a twenty-two-kilogram cast iron vise, as well as dozens of kilograms of various steel plates and round steel materials.

If he, a high school student, huffed and puffed to carry these iron lumps home every day, it would probably trigger some bad associations from his family members.

Moreover, he also needed time to pick up goods at the intra-city logistics outlet, and even more so, a legitimate reason to go home later every night, or even occasionally skip evening self-study.

Right now, isn't this the best pass?

Jiang Lin raised his head, looking into Old Liu's expectant eyes, his expression very naturally revealing a trace of just-right fatigue.

"Teacher Liu, a separate classroom won't be necessary. Detaching myself from the class collective would instead easily cause pressure. However, I have indeed encountered a bit of a bottleneck right now."

"What bottleneck, tell me in detail?" Old Liu immediately became nervous, even putting down his thermos cup.

"In the Physics part, I found that many Physics models I still keep on paper. To ensure nothing goes wrong, I need to do some practical hands-on deductions. Not doing problems, but truly building some mechanical structures, and feeling the actual resistance of torque, friction, and electromagnetic conversion."

Jiang Lin spoke casually, taking Sun Ming's distress and packaging it slightly.

Old Liu was stunned.

If any ordinary student were to tell him that they didn't want to do test papers anymore and wanted to go play with mud and building blocks, he would have long since slammed his palm on the table and scolded them mercilessly.

But sitting in front of him was the city's number one student.

As for the world of top students, although he, Old Liu, didn't understand it, he was deeply shocked and believed in it implicitly.

"You mean, you need time to do experiments?" Old Liu tentatively asked.

"Yes, I need to buy some materials myself and do some physical verification hands-on. Therefore, I was thinking that for every week's evening self-study from now on, as long as it's not a unified test, can I arrange it freely?"

Meeting Old Liu's gaze, Jiang Lin spoke in a sincere tone.

Old Liu frowned and pondered for a full minute.

Letting a student skip evening self-study to run around blindly one hundred days before the Gaokao was definitely a rule-violating operation.

But thinking of Jiang Lin's heaven-defying scores, as well as the very persuasive, calm attitude he had just spoken with, Old Liu's bottom line couldn't help but waver.

"Alright, if you don't want to attend evening self-study, I can make flexible arrangements for your evening self-study."

Old Liu made up his mind and heavily placed his thermos cup onto the desk.

"But let's make the ugly words clear beforehand, in next month's second mock exam, if your total score drops by more than five points, this special approval will be canceled immediately, and you will have to honestly go back to the classroom to grind test papers."

"Thank you, Teacher, rest assured, my score won't drop." Jiang Lin stood up and bowed slightly.

The time permissions for the Real World were secured.

Next, a place was still missing.

After school in the afternoon, Jiang Lin did not go straight home.

Behind his residential community was a cluster of old teachers' residential buildings built in the early 1990s.

This cluster of teachers' buildings was built in the early 1990s. In the early years, it was the family quarters for a nearby elementary school and a factory-run middle school. The red brick exterior walls were already mottled, and the spacing between the buildings was very narrow.

Having gone through nearly thirty years of wind and rain, property rights were scattered and residents were mixed. Many residents on the first floor had privately added small garages with rolling shutter doors at the base of the outer walls, and no one cared much about it.

These garages were originally used to park bicycles or early motorcycles, and their area was not large.

This was precisely the place Jiang Lin needed.

It didn't need a yard, didn't need living facilities, and didn't even need windows.

As long as there was a rolling shutter door to block the outside view, and as long as the logistics box truck could drive to the front of the door to unload goods, that was enough.

The most crucial thing was that this kind of place was less than five hundred meters walking distance from the building where his home was located, perfectly fitting his ant-moving strategy.

Jiang Lin walked a circle along the enclosing wall of the teachers' buildings, his gaze searching among those rolling shutter doors.

Soon, he saw a dusty silver-gray rolling shutter door with a faded red piece of paper pasted on it: "Garage for rent, can park tricycles, pile up sundries, phone XXXX..."

He took out his mobile phone and made a call.

Less than five minutes later, a lean and thin old man walked out from the neighboring unit door.

The old man's surname was Qin, and everyone in this area called him Old Qin.

Two joints of his left index finger and middle finger were missing.

Hearing people downstairs say so, it was because he suffered losses once beside a milling machine when he was young.

Now that he had retired, his daily joy was sitting under the big tree downstairs playing Chinese chess.

Old Qin looked Jiang Lin up and down, who was wearing a high school uniform, his brows furrowed into the shape of the Chinese character "chuan": "You're the one renting? What is a little brat renting a garage for? My place here definitely won't be lent to you half-grown kids to use as some secret base for smoking and playing cards."

"Grandpa Qin, I'm just renting it to store some review materials, and some scrap metal for my own Physics experiments." Without changing his expression or skipping a beat, Jiang Lin pointed to the bulging schoolbag on his back, "The space at home is small, my mom thinks it's messy and won't let me do it in the living room. I definitely won't cause you any trouble."

Old Qin looked at him with skepticism twice, but looking at Jiang Lin's honest and dependable face, he didn't ask any more questions.

He untied a bunch of keys from his trouser waistband, picked out one, and poked it into the keyhole of the rolling shutter door.

Clatter——

The rolling shutter door was pushed up, and a rush of air mixed with the smell of engine oil, dust, and a slight mildew smell hit his face.

The space was not large, the cement floor was uneven, spiderwebs hung in the corners of the wall, and only an incandescent light bulb hung from the ceiling.

"You see it, these are the conditions. Usually, other people just rent it to park an electric tricycle or put some sundries and things." Old Qin stood at the doorway and introduced casually, "One hundred and fifty a month, two hundred deposit, cash payment, no contract. If you think it's shabby, go find somewhere else."

"No problem." Jiang Lin didn't bargain at all.

This kind of hidden corner, this kind of indifferent landlord, exchanging one hundred and fifty yuan for a rolling shutter door and a corner that his mother wouldn't casually clean up was also acceptable.

Jiang Lin counted out the money from his wallet and handed it over.

Old Qin took the money, held it up to the light to check, and finally grinned: "Alright, the keys are yours. Remember, don't get into any illegal activities."

Finished speaking, Old Qin waddled away, hurrying to take a spot for chess under the big tree.

Jiang Lin walked into the small garage and reached out to pull down the rolling shutter door.

The moment the door completely hit the ground, the hustle and bustle of the outside market was abruptly cut off.

He looked around once, took out a tape measure from his schoolbag, squatted down, and began to measure the dimensions of the ground.

Two point eight meters long, two point one meters wide, less than six square meters.

He roughly gestured the layout on the ground.

Heavy tools were placed on one side against the wall, the vise and bench drill occupied one corner, standard parts and materials were stacked against the other wall, leaving a narrow aisle in the middle.

It was enough.

He pulled up the rolling shutter door again and rode his bike to a nearby building materials grocery store.

He dragged back a cut moisture-proof mat, a roll of thick plastic film, two of the cheapest angle-iron storage racks, a broom, and a plastic dustpan from the grocery store.

Returning to the garage, he gave it a thorough cleaning, covered the entire floor with the moisture-proof mat, and pasted the plastic film half a meter high along the base of the wall.

Jiangcheng's spring was damp, and this garage had no dehumidification equipment, so it could only rely on doing a little Physics isolation.

The angle-iron storage racks were placed against the wall according to the previously measured dimensions, and a damp rag was used to wipe clean every layer of the partition boards of the storage racks.

This was his first storage and processing room.

Less than six square meters, no windows, no water, no toilet, but a door that could be locked.

Old Liu's special approval took effect starting today.

From now on, every night that didn't require a unified test, he could come here to receive goods, inspect goods, number them, stock them into inventory, practice filing and drilling, build that crude yet usable yaw bearing prototype, and then bring all failures and successes together into the Wasteland.