The Applied Research Of Level 3 Features In Fingerprint Identification

At present,the study of fingerprinting in the world has basically reached a stage of maturity.Today’s research focuses include the search for new detecting materials and the identification of difficult fingerprints.In civil cases,the name writing may be due to peeling,finger injury or other reasons,or due to dishonest,illegal purposes,etc.,intentionally changing the normal fingerprint printing action,resulting in a small area of ? ?the seal,low clarity of the line.The fingerprints left by the suspects in crime scenes are all related to their criminal actions rather than being consciously left behind.Therefore,the fingerprints found are not as clear as the fingerprints in civil cases,and these are given to the existing primary and secondary levels.Fingerprint identification of features poses challenges.In the classic textbooks of fingerprinting,the third level characteristics of fingerprints include the edge morphology,width of ridge lines,width of small furrows,fine dotted lines,and sweat pores,and are hard to be recognized compared with the secondary characteristics,but are rarely used in the identification of fingerprints,and because they are too microscopic and easy to be effected by surroundings,making the reliability of fingerprint identification questioned.The third level characteristics are more microscopic than the fingerprint secondary features,and arespecific to the characteristics of a certain root line.The fundamental source of these features is the difference in the growth of the dermis nipple.It is generally believed that the fingerprint three-level feature is related to features of sweat pores,edge features of the ridge lines,fine lines,and scars and wrinkles.The line itself is arranged by a variety of nipples that are different from each other,and not all of the nipples on the same stripe line grow together.Some of the lines in the stripe line are a nipple protrusion,and some of the two nipples protrude together,even three or four nipples;from the point of view of nature and phenomenon,the dermis nipple is the essence,the epidermis and papillary line is the external manifestation,so the number of dermal papillae,the arrangement of the shape will be in the appearance characteristics of the papillary ridge line reflected.Under the concept of three-level features of fingerprints,the object of identification becomes a rifling,a furrow,etc.As long as there are ridges,it is possible to find high-quality three-level features.The size and incompleteness of fingerprints can be determined.It is no longer a necessary prerequisite for the identification of conditions.This is a clear reminder of the current predicament of solving the problem of low utilization rate of fingerprint identification materials and unable to draw exact identification opinions.The features of sweat pores,papillary line edges,scars,and wrinkles in fingerprint are well recognized by the academic community,in addition,the fine-dotted lines,hollow features of ridges have also been proposed by some scholars.Sweat pore is the opening of the sweat gland conduit on the papillary line and is distributed on the breast ridge line.It does not appear in the small furrow.The sweat pore of every person,every finger,and every part of the finger has a unique shape,size and distribution that can be used for personal identification.The shape of the papillary line edge refers to the fact that the edge of each papillary line is not smooth,but has morphological changes such as unevenness,width,and reflecting the differences in the growth of the papillary nipple.The morphological characteristics of the ridge line are very widely distributed,as all sites with papillary ridge lines may be observed.Differences in dermal papillae and differences in sweat pore position offsets can affect the shape of the papillary ridge line.Although the edge details are verysubtle and susceptible to factors such as the size of the force,the strength of the direction,but its stable relative position can be used as a reference in identification.The thin dotted line is also called the papillary line,or the thin line at the base.It is a continuous thin line that appears in the groove between the thin lines of the mastoid,intermittently distributed and similar to a papillary line-like structure,but essentially different from a papillary line.Scars are formed by tissue regeneration after localized skin injury in the fingers.Their size,shape,location,length,and their relationship with surrounding wrinkles and papillary ridge lines have high appraisal value.The small and superficial grooves formed by skin relaxation and accumulation activities are called wrinkles.The mechanism of formation of wrinkles on hands is completely different from that of fingerprints,and it becomes deeper and more numerous with age,not life-long change,but it also has Longer term stability.Whether it is the first-level,second-level or third-level features of fingerprints,the ultimate purpose is to apply fingerprint identification practices to help judges draw the same or different conclusions.There are still many problems to be explored for the application of fingerprint three-level features.The principle of the application of fingerprint three-level features should be determined as follows: In the case where fingerprint identification conditions are not good enough,after checking primary and secondary features,a third-level feature test can be added when a firm conclusion cannot be reached.It is difficult to locate three-level characteristics of a single fingerprint,and it must rely on other fingerprint secondary characteristics to find and compare.The following points need to be noted when using fingerprint three-level feature fingerprint identification: The sample and the fingerprint of the sample are consistent in the first-class features such as pattern,overall line direction,and triangulation features,or at least no obvious conflict;the sample fingerprints are printed repeatedly and repeatedly under the same conditions to obtain enough for comparison;the inspection and identification process needs to be more detailed and cautious;the detailed characteristics should be at least five.After adding the third-level features,the standard number of fingerprint details should be less than before.In the introduction of valuable and accurate three-levelfeatures,“6 details features + 2 features of fingerprints> 8 details” and “5 details features + 2 fingerprints 3 features + 8 details "The details of "detailed features" and"three-level features" are not fixed and unadjustable.The value of small-eyes,bridges,and small hooks in the details of the second-level feature level must be greater than the starting points,the disagreement points,and the combination points.This is also the case with the same three-level features.In the case that there are already several detailed features,if a valuable three-level feature is found,it can largely corroborate the details that have been determined so that the opinions of fingerprint identification can be completed from the "most likely the same" to the "same".However,simply using the three-level feature can not make the same conclusion,nor can it come to the same conclusion.To maximize the use of fingerprint three-level features,more attention must be paid to all aspects,especially the requirements for sample collection.This poses higher requirements for grassroots criminal investigators and court staff.At the substantive stage of the appraisal,higher requirements were placed on the appraisers,which not only required the precipitation of professional knowledge,but also required the appraisers to have a wealth of experience.In addition,they must have extraordinary patience and care.Because the fingerprint three-level feature has relative stability and certain variability,the identification practice will be subject to certain identification conditions,but this does not negate its important value in fingerprint identification,especially in difficult fingerprints identification,as long as it is correct.Knowing how to grasp the changing rules and application conditions of fingerprint three-level features will certainly play a more and more important role in fingerprint identification.