"Troubleshooting?"

They were so busy that after dark, the captain of the picture scout team came over and asked Jiang Yuan for instructions.

Their early progress was very fast. It only took half a day to find the surveillance video of the suspicious vehicle. If the night shooting capabilities of several cameras were not too weak, this case should have been a typical case solved quickly.

For the same reason, when existing surveillance videos are unavailable, what the detective team can do is conduct a large-scale investigation of the vehicles during the time of the crime.

Logically speaking, the suspicious vehicle drove past the stolen company's wall at 4:10 in the morning, and turned around 300 meters ahead at 4:50. The time of the crime is basically certain. If the time is slightly longer, we can investigate again.

The vehicle bayonet on national highways and highways, especially the vehicle bayonet on national highways, has a high probability of being able to accommodate suspicious vehicles.

However, this job is definitely not easy.

The traffic around Changyang City is busy. Even at 4 o'clock in the morning, there are still many vehicles coming and going, especially freight vehicles, some of which are specially driven at night.

Without knowing other information about the vehicle, it would take an hour or even longer to check the vehicles passing through the national highway, especially if there are so many vehicles from other provinces, the workload would be Xu Taining's level.

Jiang Yuan has done a lot of similar investigation work. Among other things, if you want to quickly obtain vehicle information, you have to send people to other provinces, or even different cities. Some people are hard to talk to, or the local work is not working properly.

If you are busy, someone must help coordinate. The forces used include but are not limited to Yu Wenshu, Jiang Yuan, provincial departments and even ministries...

Once the investigation reaches this level, according to Xu Taining's investigation theory, it is best to inspect the vehicles passing by on the highway. Although the probability is very low, but it has been done to this extent, it is not a trivial matter to increase the number several times.

…

"Although it is a method, the efficiency is too low." Jiang Yuan has been thinking about it. At this time, he did not completely reject the opinion of the captain of the reconnaissance team, but looked at Liu Jinghui and asked: "What do Liu Chu think?"

"If we want to investigate like this, the clues we currently have are not enough." Liu Jinghui analyzed calmly: "We initially determined that it was an insider. After investigating the relevant vehicles, we also have to contact the chemical plant's employee list and

For comparison with the list of former employees... For normal procedures, this investigation strategy is definitely no problem, but for a very large-scale investigation, the evidence we have obtained from the current investigation is too insufficient."

Wang Chuanxing, who was next to him, had been taking notes. At this time, he said leisurely: "It is Liu Chu's reasoning that the criminal is a mole."

Liu Jinghui glanced at Wang Chuanxing sharply: "Inference! No! No evidence!"

The captain of the investigation team also realized that the investigation he was talking about represented a huge workload, investigation costs, and responsibilities, so he couldn't help but retreat: "Now that Director Liu has started to talk about the evidence, then we really

We should look for more evidence."

Liu Jinghui felt that his waistline was about to get angry, and repeated: "Inference is a judgment made after considering the evidence from all parties... How about checking the footprints?"

Liu Jinghui is also extremely familiar with Jiang Yuan's skills.

There are two types of evidence commonly used in theft cases, one is fingerprints, and the other is footprints. For ordinary criminal police, the former is the most commonly used, but for more advanced theft cases, footprints are a big killer. Thieves

You can avoid fingerprints by wearing gloves, and never enter or leave a house floating in the air.

Although the footprints at the crime scene are messy and damaged, in the final analysis, they are the footprints of dozens of people. If Jiang Yuan can identify them one by one, and then investigate these dozens of people separately, it will be a way.

Jiang Yuan lowered his head and glanced at Liu Jinghui sideways, and said: "The workers in the factory are not very different in height, weight, and age. They are engaged in the same profession, and they wear acid and alkali-resistant work shoes issued by the factory. In addition,

Repeatedly stepping on the road, it is very difficult to match the footprints with the people."

"It's very difficult. It means it can be done, but it's laborious?" Liu Jinghui tried to translate.

"Not only that." Jiang Yuandao: "We need to compare them one by one and have samples."

Liu Jinghui translated again: "In other words, in theory, you can find the footprints of current employees for analysis and comparison. If there are footprints of non-employees on the scene, you can judge that they are suspects. However, if you want to identify the suspect

You need to have footprints for comparison, so you have to send criminal police to find all the employees who have resigned, and then take the footprints..."

Needless to say, Jiang Yuan said that Liu Jinghui was already aware of the difficulty: "The number of employees who have resigned is large, and they may not all stay in the province. Moreover, the criminals may deliberately avoid our investigation... Well, if it is a conspiracy,

The footprints left at the scene may also have been left by the criminal who was completely out of sight.”

The last point is the most fatal. It reduces the feasibility of footprint investigation by more than two levels. Of course, it is not impossible to use it. If there are no other clues at all, this solution can be tried reluctantly.

It is more difficult to get 100% answers in the direction of investigation than to get 100% empty-handed answers.

"I'll think about it again..." Liu Jinghui entered a state of self-renovation.

Jiang Yuan thought about it for a long time, and when he saw this, he said: "In this case, I think it's better to analyze the vehicle."

"How to analyze it?" the captain of the photo investigation team asked immediately. He had been watching the video for so long and still had no idea at all.

"You can't see the suspicious vehicle from the surveillance video, but look here..." Jiang Yuan took out the surveillance camera when the vehicle turned around and said: "Although you can't see the appearance of the car clearly, the headlights of the vehicle are shining on the ground.

The picture on it is still very clear.”

"This..." The captain of the detective team looked at Jiang Yuan, not knowing what to say or what to ask.

Jiang Yuan said directly: "I think we can analyze the layout characteristics of vehicle headlights. The headlight layout of different vehicles is still different. Although there are matryoshka dolls, if you can determine a brand, it can still reduce a lot of workload.

.”

"Can it be done?" Liu Jinghui suddenly became energetic and his ongoing thinking stopped.

Jiang Yuan nodded: "You can give it a try."

This book was last updated in ##!! Updated!

Jiang Yuan also has LV3 vehicle trace identification, and with the corresponding image detection technology, it is no problem to narrow the scope to a certain extent.

Wei Shijin, who had been listening with open ears, came over at this time, looked at the two blurry light beams on the screen in front of him, and asked hesitantly: "How to analyze this? Use mathematics?"

"Do you have any ideas?" Jiang Yuan asked Wei Shijun.

Wei Shijun really thought about it for a moment, then his whole body trembled violently, and he asked in a low voice: "Use linear algebra?"

Although he didn't study it seriously, he was really buried in linear algebra for two days.

Jiang Yuan looked at Master Wei and asked curiously: "How to use it?"

"Calculate based on the projected area?" Wei Shijun tried: "Maybe we can estimate the height of the vehicle or something..."

Jiang Yuan listened carefully, nodded, and said, "You can give it a try, just treat it as your homework."

"Oh... Hey, should I do it myself? What about you?" Master Wei asked hurriedly.

"We can just go to the site for an experiment." Jiang Yuan gestured twice on the screen with his finger and said: "Go to the site and directly measure the distance between these two points, and you will know the distance between the headlights. Find a car again,

Drive to the same position and look at the position of the headlights to determine the height of the car..."

Jiang Yuan gave a brief explanation, and everyone around him understood.

Wei Shijun also understood, but he didn't understand and asked: "So, what is linear algebra used for?"
Chapter completed!