The train driver in the courtyard

As Master Lu once said, "Trust has inertia!"

Since the weather forecast center successfully predicted the once-in-a-century cold snap, the weather forecast center's emergency response level has been raised by two levels.

Emergency management departments are paying more and more attention to and trusting weather forecasts.

Upon receiving the warning, the emergency response department quickly organized personnel and convened an emergency meeting.

Everyone present was a professional, and Li Aiguo had no intention of speaking; he simply sat there obediently.

As before, Professor Huang only reported recent weather data and did not offer any opinions.

"Based on data from 120 meteorological observation stations in Southwest China, numerical model ensemble predictions were made using the Red Star computer for the next 48 hours."

The area is affected by the northward movement of warm and humid air from the western side of the subtropical high in the western Pacific, which is combined with the cold air carried by the eastward movement of a low-pressure system to the north.

Beijing, southern Yanqing, central and eastern Changping, northern Fangshan, western Tongzhou, and neighboring northwestern Langfang and northeastern Zhuozhou will experience an extreme heavy rainfall event.

The expression of Chen, the leader of the emergency response department, became serious: "How much rainfall?"

Professor Huang adjusted his glasses and continued his report: "Based on multi-source data assimilation analysis, the cumulative rainfall during the process is expected to reach 400-500 millimeters, which is expected to reach the level of an extremely heavy rainstorm."

This rainfall event was a typical example of "train effect" rainfall, characterized by high intensity, long duration, and extreme short-duration rainfall.

Wow.

After Professor Huang sat down, the conference room immediately became noisy.

Since liberation, there have been several floods, and the emergency management department has developed a complete set of response strategies. However, this level of short-term rainfall is the first time we have encountered it.

In particular, this rainfall occurred both within and around the city.

The drainage systems in cities back then were far less advanced than in later times, so if flooding occurred, it would cause a lot of trouble.

One leader expressed concern: "The various subdistricts have already received the notice and made the corresponding preparations, so there is no need to worry. However, if such a large-scale heavy rainfall occurs, it may affect production and daily life."

“Workers’ commute will also be affected, so production should be suspended,” a leader suggested.

Some leaders also expressed concern: "This is just a forecast. We can't determine whether it will rain, when it will rain, or the scale of the rainfall. How can we stop work and production?"

The meeting room fell silent immediately.

If a work stoppage or production halt is announced under uncertain circumstances, and rainfall does not occur, who will bear the resulting losses?
However, ignoring it is also inappropriate.

Leader Chen looked up at Li Aiguo and asked, "Comrade Aiguo, you personally developed this system. What do you think its accuracy rate is?"

Li Aiguo had already read the information, but he still had no idea what to expect.

Weather is highly variable, and even with constant monitoring by meteorological satellites, it is impossible to achieve 100% accuracy.

"Boss, the accuracy of weather forecasts is difficult to quantify in numbers right now, but we can work around that."

Upon hearing this, Leader Chen perked up and asked, "Aiguo, why don't you speak?"

"The main point of contention among everyone now is whether or not to suspend work and production ahead of schedule given the uncertainty of heavy rainfall."

Leader Chen nodded: "That's exactly what we're worried about."

"What if a warning could be issued half an hour or twenty minutes before the rainfall, allowing workers who are able to evacuate immediately and those who are not to move to a safe area?"

Professor Huang commented: "Our system has a 100% success rate in forecasting within 30 minutes."

Other leaders objected.

Thirty minutes?

How can we notify millions of people in thirty minutes?

"Yes, it's impossible for everyone to sit in front of the TV. Besides, how many TVs are there in Beijing?"

"Even if we notified each factory individually, there wouldn't be enough time for so many factories, let alone other units."

Seeing the room becoming noisy, Leader Chen pressed his hands down and waited until it quieted down again before looking at Li Aiguo and asking.

"Patriotic comrade, how would you manage to notify millions of people in thirty minutes?"

"Air raid siren!" Li Aiguo pointed to the loudspeaker hanging under the eaves outside the window.

Air raid sirens existed before liberation. In 37, after spotting enemy aircraft, the mountain city used arquebuses to fire blanks.

This thing was expensive and had a limited reach, so it was later replaced by the "red lantern".

The mountain city also set up a rule: a red ball was hung up, and it was a surveillance post far away in Yichang that discovered the Japanese aircraft.

The two red balls were spotted by a watchtower in Wanxian (now Wanzhou District, Chongqing), indicating that the Japanese aircraft had been discovered.

After the enemy plane returns, it will then hang a green lantern.

Old Chen from the locomotive depot comes from a mountain city and can still sing the local nursery rhymes.

"Airplane head, two ounces of oil, Goose Ridge, hanging red ball."

Japanese planes dropped bombs, and blood flowed everywhere in the mountain city.

The alarms never stop, and the hatred is endless.

Chimneys became anti-aircraft guns, and anti-aircraft planes banged their heads.

"My son wants to join the army too, to chop off the heads of the Japanese devils with a big sword."

After liberation, air raid sirens were widely promoted to prevent enemy aircraft from intruding.

As a key city, the capital was equipped with air raid sirens in every street, factory, and school.

Air raid sirens have evolved from red lanterns to electric siren systems.

Air raid sirens have a unified management system that can quickly disseminate information about incoming enemy aircraft, making them the most suitable method for emergency early warning.

In later generations, we also developed a complete system for using air raid sirens to warn of impending rainstorms. For example, in a Level I emergency response, air raid sirens need to be sounded.

However, with the development of technology, people have more convenient ways to receive information, and this method has gradually been used less and less.

Using air raid sirens in this era is just right.

After listening to the explanation, the experts from the emergency response department carefully considered it and realized the feasibility of this method.

"A 30-minute advance warning can alert everyone to the impending rainstorm and avoid false alarms."

"I think it will work."

Leader Chen was somewhat excited. After taking notes, he continued, "Comrade Aiguo, besides these, what other thoughts do you have?"

He felt that this young man seemed to have a special understanding of emergency response.

Since the matter was of great importance, Li Aiguo did not hold back and shared some of the experiences from later generations one by one.

The alarm should use different sound effects depending on the situation.

In this era, it was already stipulated that when enemy planes approached, the warning sound would be a series of short, sharp beeps, while the warning sound for a nuclear strike would be a long, undulating siren.

During heavy rainstorms, the alarm should sound for three seconds and then stop for three seconds, repeated 30 times.

This design draws inspiration from psychological research, which suggests that humans develop conditioned reflexes to sound waves of specific frequencies.

Upon receiving the alarm, buses and trains are strictly prohibited from entering the underground tunnel, and personnel must immediately evacuate to higher ground.

As for the reservoirs near the capital, militia members need to be on duty to release floodwaters in advance, and if the water level is found to exceed the warning line, rescue efforts need to be organized.

Prepare the supplies and distribute them as soon as the rain stops.

The medical team also needs to prepare in advance and urgently transport a batch of drugs to prevent dysentery.

“Each neighborhood needs to prepare sandbags in advance. It would be best to make flood control sandbags a regular practice. Those things can also be used to put out fires.”

Li Aiguo devised this method not only to prevent this rainstorm, but also to prepare for a major event in future generations.

A routine forecasting system can also be established in coastal areas to cope with strong typhoons.

Leader Chen also realized this, and after summarizing the suggestions, he nodded repeatedly: "Comrade Aiguo, these methods are all quite good, thank you so much."

Faced with the outstretched hand from Leader Chen, Li Aiguo quickly returned both hands and grasped them tightly: "This is what I should do."

Subsequently, experts from the emergency response department made adjustments based on the actual situation, and these methods became more suitable for the actual circumstances.

Emergency response departments sprang into action. Various subdistrict offices also received air raid sirens warning of the approaching torrential rain.

The neighborhood committee staff went door-to-door reminding residents: "If you hear a wailing sound, run to higher ground immediately."

"Waaaaah, waaaah?"

"It's woof woof woof woof."

"Waaaaah, waaaaah?"

"."

The street office official was silent for a moment, then looked up at Jia Dongxu: "Are you just causing trouble?!"

Jia Dongxu: "."

*****
in the afternoon.

Li Aiguo returned to the courtyard house and studied the flood prevention instructions with the residents, and helped fill sandbags.

Sandbags are made by filling specially made canvas bags with sand. These bags are resistant to corrosion and sun, and are also very durable.

Li Aiguo and Xu Damao picked up shovels and filled sandbags. The bicycle from Uncle San's house was requisitioned, and Zhang Gangzhu pushed the sandbags and piled them up near the gate and the passageway.

“Uncle, there are flood prevention signs written on these sandbags, so don’t get any funny ideas,” Li Aiguo reminded Uncle when he saw Uncle’s small eyes fixed on the sandbags.

"How could that be!" the third uncle quickly waved his hand.

Ever since he was beaten for reselling antiques, the Third Uncle has found a new way to make money: he goes from street to street collecting old items and reselling them at the pigeon market.

He's starting to resemble a junk collector, no longer interested in such small sums of money.

It was nearly 1:30 p.m. when the sandbags were finally piled up.

Feeling sticky and covered in sand, Li Aiguo took off his vest and washed up by the pool in the central courtyard. He then dried himself off with a towel, got on his motorcycle, and returned to the locomotive depot.

The locomotive depot also received the notification. When they entered the workshop, Zong Xianfeng and several technicians were there, making "whoosh whoosh whoosh" noises.

"Patriotism is here, everyone, let's get started."

When Zong Xianfeng saw Li Aiguo arrive, he led the technicians to continue assembling the excavator.

Excavators are classified into three types according to tonnage: large, medium, and small, each with its own unique operating environment.

Li Aiguo developed a medium-sized excavator, weighing 35 tons, with a bucket capacity of 1.1 cubic meters, and equipped with a backhoe as standard.

The four-cylinder diesel engine has a maximum power of 200KW, and thanks to the electronic hydraulic system, fuel consumption can be reduced by 15%.

The main overflow pressure is 45MPa, and the main pump flow rate is 335L/min (570L/min for mining version).

The boom is welded from a single plate, the stick has a fan-shaped design, and key areas are reinforced with plates.

This type of excavator is suitable for both road repair and mining, and its tracked wheel system makes it even more suitable for harsh environments.

With all the excavator parts in place, Li Aiguo stroked his chin. Luckily, the crane had been arranged in advance; otherwise, this thing really wouldn't have been able to be installed.

After a busy day, most of the parts are almost done, and it's time to weld the boom.

This part is related to the durability of the excavator, so Li Aiguo plans to hire two level-eight welders from the machine repair shop to take charge of it.

He had talked to Liang Ladi before, and they said that the best welders in Beijing were from the machine repair shop.

Liang Ladi may have been exaggerating.

Considering that a large part of machine repair work in those days involved welding.

Even a broken shaft can be welded back together, which shows the skill of the welders at the machine repair shop.

Director Zhang of the maintenance workshop felt that Li Aiguo was being too cautious. There were good welders in the workshop, but he still turned around and contacted someone else.

The Qianmen Locomotive Depot and the Locomotive Repair Shop did not have much contact.

The leaders of the machine repair shop had heard that the locomotive depot was very generous, and that every employee who came to help would receive a share of fine flour.

The factory notified two level-eight welders, and considering that Liang Ladi had connections with the Qianmen Locomotive Depot, they asked them to bring Liang Ladi along as well.

"Wow, Brother Aiguo, this is huge!" After introducing the two experienced workers to Li Aiguo, Liang Ladi circled the excavator, marveling at it.

"This is the first time in my life I've ever seen such a big machine."

Just as Li Aiguo was about to give an introduction, Liang Ladi added, "If this thing breaks, it'll probably be very difficult to repair, right?"

Li Aiguo: "."

Zong Xianfeng and Director Zhang felt that Liang Ladi had developed a professional habit.

Liang Ladi's words, however, reminded Li Aiguo.

As construction machinery, even the best quality excavators are prone to malfunction when working every day.

Once mass production begins, a maintenance team will be needed, something that the workshop alone cannot accomplish.

The workshop has too few technicians, and they also need to manufacture large excavators specifically for mining, so they can't spare any more manpower.

Seeing Liang Ladi's excited expression, Li Aiguo felt that they could join forces with the machine repair shop to form a repair team.

We can talk about that later; let's deal with this one first.

"Thank you for your help, masters." Li Aiguo offered cigarettes to the two experienced masters and explained the welding requirements.

The two experienced workers initially thought it would be a simple task, but after hearing the explanation, they both frowned.

"To ensure that the strength of the deposited metal is higher than that of the base metal, only low-hydrogen welding wire can be used."

"High-chromium alloy welding wire can be used for wear-resistant areas."

"There's also the issue of preheating. We need to heat it first to lower the layer temperature so that after welding, the two layers won't separate."

Because the excavator's boom is too large, conventional arc welding is no longer effective.

After some discussion, the two decided to choose the latest welding process: MIG welding.

This technique was invented by Russians such as Lyubavsky and was introduced to China a couple of years ago. By using carbon dioxide as a protective gas, it significantly improved welding efficiency and quality.

Seeing the two technicians notify the machine repair shop to send over a large batch of equipment, Director Zhang shrank back.

No wonder Li Aiguo thought the maintenance workshop couldn't handle this welding; he didn't recognize any of these components.

Li Aiguo squatted down to the side and took a puff of his cigarette. Xiao Mei had already invented plasma arc welding, which was a good technology. If there was an opportunity, he could try to get it back.

The entire welding process lasted for most of the day, and it wasn't until almost evening that the welding was finally completed.

The welds are seamlessly integrated, and when painted red on the outside, they are completely invisible. Both sides of the boom are made of reinforced alloy steel, providing exceptional load-bearing capacity.

After the inspection, the two veteran welders each received ten jin of refined white flour, and they were so excited that they couldn't stop smiling.

Liang Ladi was responsible for liaison and also received five catties of refined white flour.

After the boom was welded, it was already close to evening. Li Aiguo had all the parts covered with rainproof tarpaulins, left work early, and planned to continue working tomorrow.

Back in the courtyard house.

The flood prevention preparations in the compound were almost complete. Li Aiguo was surprised to see Xu Damao returning with two old hens.

"Brother Da Mao, where did this old hen come from?"

"I bought them from the countryside, intending to keep them to lay eggs. Xiao Xu's hair is a bit yellow, and my mother said she should eat more eggs."

As Xu Damao spoke, he stuffed the old hen into the cage in front of the door.

These days, there are no regulations in the capital that prohibit raising poultry, so the residents are used to it. However, Jia Dongxu thinks that kind of thing is too disgusting.

"It has nothing to do with us that they're raising an old hen. Let's not get involved. Instead, let's think about how to deal with Jia Zhangshi and Jia Ba."

Qin Huairu saw Jia Dongxu squatting at the door staring at the chicken coop and gave him a few words of advice.

Jia Dongxu nodded and limped back into the house.

He strained his back while digging the irrigation ditch today, and it's really painful.

(There will be another chapter tonight ^_^) (End of this chapter)