Objective evaluation of similarity scores derived by Evofinder® system for marks on bullets fired from Chinese Norinco QSZ-92 pistols.

In recent years, many studies have been conducted in the field of firearm identification with the objective of providing an objective method of evaluating the comparison of cartridge cases. However, less attention has been paid to the objective evaluation of bullet comparisons. In this study, 1 000 registered Chinese Norinco QSZ-92 pistols were used, and a database of 2 996 bullets was constructed. Both the receiver operating characteristic (ROC) curve and the score-based likelihood ratio method were used to objectively evaluate the similarity scores derived by the Evofinder® system. The results indicate that this system has excellent ability to discriminate between the selected pistols. This paper proposes an objective evaluation method, which serves as a response to the ongoing debates regarding the foundation of the discipline.

Performance Evaluation of a Registered Ballistic Database Using the Evofinder® System.

Firearms for police in China are registered along with their fired bullets and cartridge cases. A Registered Ballistic Database (RBD) of 1000 Norinco QSZ-92 pistols with registered ammunition was established and was evaluated through the Evofinder® system. In this research, 1000 bullets and 1000 cartridge cases were randomly selected and correlated against an RBD of 2996 bullets and 2999 cartridge cases. Examiners found that successful identifications all ranked 1st, supported with land (100%), groove (97%) engraved areas, and primary marks (85.6%) for bullets, and firing pin impressions (99.8%), and breech face marks (99.9%) for cartridge cases. Two known matches (KM) for the same pistol rank in the top two (100%). The distribution of similarity scores varies from marks; however, the Evofinder® system could still effectively distinguish known matches from known nonmatches (KNM) for either bullets or cartridge cases. This study demonstrates the efficiency of the RBD.

[Construction of individual-based ecological model for Scomber japonicas at its early growth stages in East China Sea].

By adopting FVCOM-simulated 3-D physical field and based on the biological processes of chub mackerel (Scomber japonicas) in its early life history from the individual-based biological model, the individual-based ecological model for S. japonicas at its early growth stages in the East China Sea was constructed through coupling the physical field in March-July with the biological model by the method of Lagrange particle tracking. The model constructed could well simulate the transport process and abundance distribution of S. japonicas eggs and larvae. The Taiwan Warm Current, Kuroshio, and Tsushima Strait Warm Current directly affected the transport process and distribution of the eggs and larvae, and indirectly affected the growth and survive of the eggs and larvae through the transport to the nursery grounds with different water temperature and foods. The spawning grounds in southern East China Sea made more contributions to the recruitment to the fishing grounds in northeast East China Sea, but less to the Yangtze estuary and Zhoushan Island. The northwestern and southwestern parts of spawning grounds had strong connectivity with the nursery grounds of Cheju and Tsushima Straits, whereas the northeastern and southeastern parts of the spawning ground had strong connectivity with the nursery grounds of Kyushu and Pacific Ocean.

The direct pyrolysis and catalytic pyrolysis of Nannochloropsis sp. residue for renewable bio-oils.

Nannochloropsis sp. (a kind of green microalga) residue was pyrolyzed without catalyst or with different amount of HZSM-5 catalyst in a fixed bed reactor in nitrogen flow. The effects of pyrolysis parameters such as temperature and catalyst-to-material ratio on product yields were studied. The bio-oils obtained were analyzed by elemental, GC-MS and FTIR analysis. The results indicated that the bio-oils from catalytic pyrolysis of Nannochloropsis sp. residue (BOCP) had lower oxygen content (19.5 wt.%) and higher heating-value (32.7 MJ kg(-1)) than those obtained from direct pyrolysis (BODP) which had an oxygen content of 30.1 wt.% and heating-value of 24.6 MJ kg(-1). The BODP mainly consisted of long carbon chain compounds with various terminal groups (LCTG), while the BOCP mainly consisted of aromatic hydrocarbons. These properties of bio-oils demonstrated that the Nannochloropsis sp. residue can be used as a renewable energy resource and chemical feedstock.