Small knowledge of fingerprint lock

As an identification, "fingerprint" originated from criminology and forensic medicine at the end of 19 and the beginning of the 20th century. Due to biological reasons, there are individual differences in human fingerprints. This difference is reflected in people and the uniqueness of fingerprints, that is, everyone's fingerprints (three basic patterns, arch, ring and line) are different and have their own characteristics. This characteristic does not change with the change of time and environment, so it is widely used in the identification of criminals and the production of special documents.

Molecular biology tells us that human genes are * * *, that is, different biological groups have their specific DNA composition, and there are differences among individuals. This difference is essentially manifested in the difference of genes, that is, the difference of DNA composition sequence. At present, with the maturity of DNA analysis technology, DNA identification has been widely used to judge the blood relationship between different people, such as paternity test, corpse identification, biological species identification and so on. The identification of its essence is completely consistent with fingerprint identification, but because of the huge amount of DNA, the number of the same gene sequence is much larger than that of different gene sequences, and genes, as the basic composition of organisms, are very different because of their instability. Therefore, it is very important to distinguish the selected objects. A specific DNA fragment with great variability should be selected as the characteristic fingerprint, which is actually judged at a certain point, and the judgment of this point does not affect the integrity. DNA can be applied to the fingerprint of traditional Chinese medicine, which can be used for species identification. There are great differences between different plants, so it is easier to distinguish between true and false, but animal medicine is relatively difficult, but mineral medicine is not. Secondly, it can be applied to the identification of the same type of plants with different biological isolation, that is, the identification of the origin. However, these two kinds of identification are the identification of biological attributes. Although it is not disturbed by the outside world, the secondary metabolites of plant drugs (mostly medicinal parts) are more susceptible to environmental influence, and there are uncertain factors between them. So I think DNA as a fingerprint can be used to identify species, but there are many kinds of plants and the research is not deep enough. The research and development cost is very high, and there is still a considerable distance from practical application. But in the long run, protecting Chinese medicine resources and establishing gene bank have its special function.

In the analysis and research of traditional Chinese medicine, it is found that plant medicine is a mixture of various chemical components, and its efficacy cannot be explained by a single component, but is the result of the joint action of various active components. Therefore, the determination and evaluation of a single active ingredient can not explain the quality of traditional Chinese medicine, and many index ingredients detected at present are not unique. When the concept of western medicine detection is completely applied to Chinese medicine, there are problems of covering the whole and cutting the whole. Therefore, the concept of fingerprint is introduced into the analysis of traditional Chinese medicine, and some analysis with certain characteristics is used to characterize the characteristics of traditional Chinese medicine components. Here, the meaning of fingerprints has changed. Unlike the "absolute uniqueness" of individuals emphasized by fingerprints in criminology and the inherent genetic characteristics in DNA fingerprints (which can be "absolute uniqueness" between individuals or "uniqueness" between groups), it is through certain methods (such as HPLC, GC, TLC, HPLC-MS, GC-MS, FTIR, etc.). For specific objects (such as Chinese herbal medicines, extracts, decoction pieces, injections, etc.). ), including its process, the obtained characteristics and relatively stable chromatogram can be used as a reference for identification and quality control. Because most of the chemical components of Chinese herbal medicines are secondary metabolites, they are easily influenced by many factors such as the environment, climate, farming and so on, and there are many uncertain factors, so it is difficult to obtain representative and universal fingerprints. At the same time, for the same object, different methods can get different fingerprints, which can not be ignored, because each method has its limitations, but in practice a certain method may be more practical and representative.

In short, I think that within the scope of Chinese medicine, the connotation of fingerprints needs to be discussed, and its representative atlas (image) should be determined according to specific objects. Strict quantification is unrealistic, and how to identify it is the key.

2. What is the knowledge of fingerprints? Be quick, be quick.

The surfaces of human fingers and palms are covered with concave and convex lines with different thicknesses, among which the thicker and less concave lines are called flexor lines; Slightly thinner than the flexor line, a large number of sunken lines are called wrinkles; The convex lines with the largest number, thinnest lines and even arrangement are called mastoid lines; The concave line parallel to the mastoid line is called a small furrow. The mastoid pattern on the skin surface of the first phalanx of the finger is composed of arch pattern (including arc pattern and tent pattern), basket pattern (including positive and negative basket) and bucket pattern (including ring pattern, spiral pattern, abnormity pattern and double jump pattern) according to certain rules. ). Arch lines are all composed of arch parallel lines without trigeminal points; The grain of dustpan pattern starts from one side, bends obliquely upwards and then returns to the original side, with only one fork point; Bucket mode has two fork points. The frequency of normal fingerprints is different in race, nationality and gender. However, among normal people of the same race and gender, the frequency of fingerprints is basically similar. For example, China people have a large proportion of bucket lines; Women have slightly more arcuate lines and slightly fewer bucket lines than men.

In China, handprints were added to housing contracts, land contracts, lease payments, divorce documents and wills a long time ago, and they must be stamped and signed later. These imprints are regarded as "certificates" for identification. But seals and signatures can be copied, and fingerprints can't be copied. It can be seen that the fingerprint "certificate" is the most reliable. With the help of modern science and technology, many countries have established various fingerprint databases. Some fingerprint banks require depositors to leave fingerprints as vouchers when withdrawing money. There is also a file fingerprint database, the fingerprints of the US Federal Bureau of Investigation; There are 65.438+0.7 billion handprints in the library, and there are children's fingerprint files to protect children's safety. Some important departments of the country have designed fingerprint doors. If your fingerprint signal is different from that on the door, you can't open the door. At present, the United States, Japanese, French and China have successively launched their own computer fingerprint automatic identification systems. Its remarkable characteristics are high speed, large amount of information processing and high precision. Even if criminals commit crimes with gloves on, they can use new reagents to extract the fingerprints of criminals through fluorescent staining and light source selection.

Patterns can be divided into three categories:

The first type is obvious lines, which can be seen intuitively under a certain angle and light, such as paint, blood, ink and other items touched by hand, which are usually printed on fingerprint cards to become basic information (some can be seen directly with your mouth, but it seems easy to pollute the evidence);

The second type is molded patterns, which refer to fingerprints found on soft substances, such as candles and clay.

The third category is latent fingerprints, which are fingerprints formed by the transfer of human natural secretions such as sweat, and are not easy to be found by naked eyes. They are the most common fingerprints at crime scenes (fingerprints left by hand sweat are the favorite of investigators). Fingers first touch grease, sweat or dust, and then touch clean surfaces, often leaving potential fingerprints. Although these fingerprints are invisible to the naked eye, they can be revealed by special methods and special chemical reagents.

The most common fingerprints that investigators come into contact with are latent fingerprints. If fingerprints are left on the surface of non-absorbent objects such as metal, plastic, glass and ceramic tiles, the inspection method will be easier. Usually, powder method can be used to select powder with large color contrast (pink pop-top can used by Sara when the transgender judge committed the crime for the second time ...), and the complete fingerprint can be extracted by scanning the surface of the article; Another method is magnetic powder method, which uses fine iron powder particles as brushes and brushes them back and forth to show fingerprints.

If fingerprints are left on the surface of absorbent articles such as paper, cards, leather and wood, they must be chemically treated before they can appear in the laboratory. Commonly used chemical methods are:

Iodine fumigation-that is, iodine crystals generate steam when heated, which reacts with the grease of fingerprint residues, and then yellow-brown fingerprints will appear, which must be photographed immediately or fixed by chemical methods;

Ninhydrin method-spray the reagent on the sample and react with amino acids in human secretions, which will show purple fingerprints (that is, the kind they often spray on paper evidence);

Silver nitrate method-after the silver nitrate solution reacts with the sodium amino in the latent fingerprint, a black fingerprint will be produced in the sun (in the third season of LV "Robot Wars", Warren used this method to obtain fingerprints on the small stone elephant);

Fluorescent reagent method-Fluorescent ammonia and phthalaldehyde react with protein or amino acid of fingerprint residue almost immediately, resulting in high fluorescence fingerprint. The reagent can be used on the surface of colored articles.

3. How to choose some small methods of fingerprint lock?

Is there a full defense design? As a high-tech product of door lock security, fingerprint lock can not only protect family property, but also reassure family members.

Especially in today's society, some contradictions still exist, so it is very important to have a comprehensive design of fingerprint lock. The fingerprint lock with high safety performance perfectly combines traditional mechanical technology with modern high-tech fingerprint identification technology, and has a 360-degree patented design of anti-theft, riot prevention, waterproof, fireproof, moisture-proof, corrosion-proof, temperature-proof, vibration-proof, abrasion-proof, rain-proof and sun-proof, and its structure is made of pure stainless steel to achieve the highest safety protection.

Is there a locking function when closing the door? In our daily life, we often forget to lock the door when we close the door, especially the vulnerable groups (such as the elderly or children) forget to lock the door when they open and close the door, which will leave a hidden danger of burglary. When choosing a fingerprint lock, be sure to know whether the fingerprint lock has the function of locking after closing the door, so as to put an end to this safe future trouble and make it safer to use.

Whether there is perfect after-sales service: According to the observation of professionals in the industry, the network of sales service points of fingerprint lock manufacturers is generally small, or even there is no after-sales service point, and the after-sales service commitment is ineffective.

4. What are the precautions for using smart locks?

1, smart locks should be waterproof. This is common sense. There are many electronic devices in the smart lock. If water enters, it will interfere with electronic circuits.

2. Generally, smart locks can only be opened with fingerprints, and the door opening button can only be pressed by hand, not with hard objects;

3. If the fingerprint collection window is used for a long time, there will be dirt on the surface, which may affect the normal use. At this time, you can wipe off the dirt with a soft cloth;

4. When using the smart lock, you should not manually turn off and turn on the sensor and password keyboard.

5. Confirm whether the current fingerprint is the fingerprint of an administrative user. If not, you can't change the fingerprint with a password. To manage fingerprints or change passwords, please follow the correct steps.

5. What are the safety knowledge of Luke's smart lock?

In-and-out real-time inspection, the highest proportion of theft is caused by negligent forgetting to lock the door or leaving the door open. According to police data, burglary from the main entrance accounts for 57%.

Therefore, it is necessary to check whether the doors and windows are closed in real time, and check in real time when entering and leaving the gate to prevent criminals from entering. Get into the good habit of locking. After entering the door, be sure to lock the door and cultivate the good habit of locking it at any time.

Don't open the door to strangers easily. If you meet a stranger visiting, don't open the door easily before confirming the identity of the other person, especially when the child is at home by himself. At the end of the year, there are also many lawless elements disguised as property and maintenance workers. Remember to verify their identities accurately.

Renting users change locks in time. For renting partners, it is best to change the lock before moving into a new home. Don't be afraid of trouble. It can not only better protect their own safety, but also ensure privacy.

It is important not to let others in and out at will. Try to choose a class C lock core. According to the safety standard grade of lock core, the highest safety grade is C, followed by B and finally A. ..

At present, most mechanical lock cores on the market are still in Grade A, and the anti-lock technology and the ability to prevent violent opening are relatively weak, and criminals can easily open them in just over ten seconds. Therefore, users can choose the C-class with the highest security when choosing the lock cylinder.

With the popularity of smart security products, smart devices such as smart door locks, smart cat eyes and smart cameras have gradually entered thousands of households, greatly improving the safety factor. For example, some smart door lock products, because of the alarm and remote viewing functions, users can know whether the door is locked in time, and they will also receive an alarm prompt when the door lock is pried open; Smart cat's eye allows users to view the status of the door remotely, and strangers will give a warning if they stay too long; Smart cameras can record images around houses in time. In short, with the help of intelligent security products, the safety factor of houses can be greatly improved.

Check the status of the door in real time. Get into the habit of checking whether the door is closed when you go in or out. When you are not at home, you can remotely check the door lock status through the APP. Or you can monitor the dynamics of your door in real time through the smart cat's eye. If suspicious behavior is detected, be sure to pay more attention and call the police if necessary. Passwords are not easy to leak. For smart door lock users, whether it is a one-time password, a periodic password or a permanent password, don't easily disclose it to strangers.

Once you notice strangers peeping around, you can use a virtual password as a cover. If someone is following you, don't panic. You can enter a specific fingerprint in advance, unlock the lock with a specific fingerprint, and the system will send the danger to the emergency contact in time.

In addition, develop the habit of changing passwords regularly to prevent the possibility of being stolen. Users who unlock the smart door lock when entering the house must unlock it in time after entering the house. In addition to unlocking the lock, remember to unlock the child lock switch to prevent the cat eye from pressing the handle to open the door.

Choosing a small black box to pry the lock with electromagnetic protection smart lock, also known as Tesla ring to pry the lock, has become another major safety hazard of smart door locks. In view of the unlocking behavior of Tesla circle, users are advised to look for the identification qualification of public security departments or related industries when purchasing locks, and change the initial password as soon as possible when using them. At the same time, we should pay attention to whether the product has electromagnetic protection and can resist the unlocking of Tesla coil.

6. What is the principle of fingerprint lock?

The fingerprint lock is novel in design and adopts very advanced fingerprint identification technology.

It completely changed the traditional design method of lock and security, and greatly standardized the security method. Fingerprint identification technology can be divided into two types: one is optical technology, and the other is capacitance technology (semiconductor technology).

The former is similar to a camera and relatively easy to copy. The latter is more secure. It collects a deeper image of the finger. According to the subtle differences of the dermis, blood flow, ridges and valleys of the finger, different capacitances are generated between the surface skin of the finger and the chip, and a complete fingerprint image is obtained through the capacitance field, so it is difficult to be copied.

The fingerprint lock stores the fingerprints of people who are allowed to enter the door. Everyone who wants to enter the door must have a prior fingerprint before entering. Once the fingerprint lock finds mismatched fingerprints, its computer system will immediately call the police.

Because everyone's fingerprint is unique, there will be no case that the key is stolen or copied. Sometimes, for the sake of safety, the homeowner has to answer questions such as blood type or birthday through the keyboard after fingerprint inspection, and then compare them with the data stored in the computer.

If the two match exactly, the door will open automatically; If not, it will close the door politely. .

7. What are the characteristics of fingerprint lock?

Characteristics of fingerprint lock Accuracy of fingerprint identification At present, the accuracy of fingerprint identification in the industry mainly refers to two aspects, namely, the true recognition rate and the false recognition rate.

The true rate refers to the probability that the fingerprint lock refuses to record the true fingerprint, while the false recognition rate is just the opposite of the true rate, that is, the probability that the fingerprint lock accepts the unrecorded fingerprint. At present, there is no minimum or maximum standard for these two probabilities in the industry, and the probabilities among enterprises vary greatly.

Generally speaking, it is acceptable that the correct rate and the false recognition rate are lower than 5% and 5 parts per million respectively. The stability fingerprint lock of electronic components is the perfect crystallization of computer information technology, electronic technology, mechanical technology and modern hardware technology.

Electronic technology plays a decisive role in fingerprint lock, and its stability directly affects the security of fingerprint lock. If the electronic part is unstable, the fingerprint lock may not respond or perform other operations when you operate, ignoring your instructions.

The stability of the ferrule is the stress point of the whole lock and the most important part of the lock. The stability of the ferrule is the most important thing in the whole lock. If the ferrule is unstable, just a few kicks will be enough, even if the technology of fingerprint lock has reached an unparalleled height.

8. What are the tips for choosing a smart lock?

Tips for choosing smart locks The choice of lock styles varies from person to person, and this part is inconclusive.

Generally speaking, it depends on the material, shape and color. At present, the lock materials on the market are mainly stainless steel and zinc alloy, as well as aluminum alloy and plastic.

If it is an entrance door, it must be made of stainless steel or zinc alloy. If it's an interior door like a bedroom, it doesn't matter The way of surface treatment is also very important. Some products look luxurious and glamorous (especially the pictures on the internet are all design renderings or processed photos), but users will find signs of fading on the handles or other places they often touch after buying them home for a period of time.

In fact, the surface treatment of such products is painting rather than electroplating, which is a manifestation of fooling users. Therefore, consumers must understand these details before buying, and agree with the manufacturer in advance how to solve such problems, otherwise the fingerprint lock bought for thousands of dollars will begin to fade in less than one year, which is really a chicken rib.

9. Five tips tell you how to maintain the fingerprint lock.

With the popularity of fingerprint locks, there are more and more users of fingerprint locks, but how to maintain and maintain those users who have installed fingerprint locks? Today I will introduce how to maintain the fingerprint lock.

Tip 1: When the battery of fingerprint lock is low, it will give an alarm at least two weeks in advance. Please replace the battery in time after hearing the alarm to avoid affecting the normal use. If it can't be opened because there is no electricity, you can use the emergency charging treasure or use the equipped emergency key to open the L lock.

Tip 2: It is forbidden to hang heavy objects. Please don't hang heavy things on the handle. It is best not to hang anything, so as to avoid long-term pressure on the handle and destroy the balance of the handle. Tip 3: Dirt cleaning Although the lock body is waterproof, please try to avoid the lock body from touching or soaking in water or other liquids.

If the shell comes into contact with liquid or salt spray, please dry it with a soft absorbent cloth. You can also wipe the dust on the fingerprint collection window with mirror cloth, because there will be dirt on the surface after a long time of use, which may affect the normal use.