Earticle

In digital forensics, searching for specific patterns in binary data is a crucial task almost always performed following data acquisition. As the volume of digital data surges and the capacity of storage media expands, there is an increasing demand for search techniques that ensure accuracy, completeness, and speed. In this paper, we explore methods to enhance search efficiency through multi-threading and memory-mapped files, while also improving the completeness of searches in corrupted data by adjusting the search resumption position after a match is found. By employing multi-threading, the parallel utilization of multiple processor cores increases the computational speed. Additionally, while some threads occupy the processor, others can access the storage medium, reducing idle times for the storage medium, and thereby maximizing the utility of the storage medium's read speed. Memory-mapped files enable direct access to the operating system’s memory region associated with the storage medium, minimizing the caching and copying stages. This reduces computational overhead and memory load compared to standard file input/output operations. In 64-bit systems, memory-mapped files allow access to files larger than physical memory as a contiguous virtual memory space of up to 2⁶⁴ bytes (16,777,216 terabytes), enabling memory-based implementations of search algorithms to be applied to large files without modification. Experimental results show that the proposed approach significantly enhances both the speed and accuracy of searches in large files, outperforming a method that relies on single-threading and standard file input/output.

The development of forensic science has significantly contributed to the resolution of criminal cases and the accuracy of legal judgments through the utilization of scientific evidence. In particular, the use of DNA barcoding to identify plant and animal species in forensic science has become an essential and reliable method because it can accurately distinguish species that are difficult to distinguish by morphological characteristics alone. However, in the case of rice species identification, it was confirmed that DNA barcoding, which primarily targets regions with low intra-species variation due to the characteristics of rice breeding development in Korea, has certain limitations. In this study, focused on an embezzlement case involving rice species identification, evaluated the limitations of three conventional DNA barcodes and five rice-specific DNA barcodes in forensic analysis. To address these limitations, we evaluated the applicability of a commercially developed rice species identification kit based on single nucleotide polymorphism (SNP) identification technology. The application of the commercial kit in rice species identification demonstrated high sensitivity and specificity, even with small amounts of test samples. Additionally, it allowed for the determination of rice species in a shorter time frame compared to traditional DNA barcoding methods. As a results, the application of commercial kits in future cases related to rice species identification may help to serve as an reliable forensic biology analysis.

This study analyzes the causes of electric shock accidents that occurred in Republic of Korea and emphasizes the importance of electrical safety devices, particularly focusing on the roles of grounding and earth leakage circuit breakers(ELBs). Through a review of actual accident cases, it was found that the absence or failure of ELBs, along with inadequate electrical installations in residential and construction environments, were major contributing factors to electric shock incidents. In response, a visualization device was developed to evaluate and visually display the operating characteristics of molded case circuit breakers(MCCBs) and ELBs under simulated real-world conditions. The experimental results showed that MCCBs effectively interrupt the circuit under overload conditions, while ELBs promptly cut off the current when a leakage current is detected. The developed testing device also enabled real-time measurement and visualization of voltage and current, allowing clear verification of breaker operations. This study emphasizes the necessity of systematic design and installation of electrical safety systems to prevent electric shock accidents and suggests its potential utility in safety policy development and educational applications.

This study investigates the statistical identity of 3D toolmarks using two types of screwdrivers. Toolmarks were created on dental wax, captured using 2D and 3D microscopes, and analyzed with MATLAB to calculate cross-correlation coefficients and likelihood ratios. Results show that same-tool toolmarks exhibit cross-correlation coefficients centered around 0.9, while different-tool toolmarks center around 0.4. Both 2D and 3D analyses followed a Weibull distribution, confirmed by goodness-of-fit tests. Likelihood ratio calculations demonstrated distinct separation between same-tool and different-tool marks, with 3D analysis showing slightly overlapping ranges due to tool shape-induced depth variations. The study confirms the efficacy of 3D microscopy for toolmark identification, with potential for enhanced 3D analysis through refined techniques and broader data accumulation.

The footwear impression found at the crime scene can serve as an important clue in identifying the suspect. Footwear impression found in the field appear in various forms, and in the case of planar footprints, additional treatment may be needed to increase the contrast between the background and footwear impressions to facilitate visual observation. There is a wide variety of surfaces on which footwear impressions can be left, so a suitable treatment method is needed. This study supplemented the safety and time required of the potassium ferrocyanide method, which is the main material of clothing and can be applied to footwear impressions on cotton and polyester, for more efficient application. By changing the composition and application stage of the working solution under the reported potassium ferrocyanide method, the safety of the worker was ensured, and the reaction time required was shortened by applying heat. The degree of footwear impression enhancement of the improved technique showed a similar degree to the result of the existing technique, and the characteristics according to the surface were similar. The shape and pattern of the footwear, large substance, abrasion marks and damages could be observed. When applying the improved technique, the same level of results as the existing technique can be obtained. It is expected that the safety of workers and the time required can be shortened. Therefore, the improved technique in this study is proposed as a soil dust footwear impression enhancement technique on porous surface.

Tool marks are critical forensic evidence significantly influencing crime scene interpretation, necessitating continuous research to enhance analysis accuracy. This study applies three-dimensional (3D) shape comparison techniques to analyze impression marks created by tools. Using a 3D microscope, we observed and compared tool marks produced by two types of screwdrivers on metal can lids, confirming the potential of 3D microscopy for tool mark analysis. We developed an objective and accurate method for identifying tool mark similarity by calculating cross-correlation coefficients between 3D shapes of different tool marks. The results demonstrated high similarity between tool marks from the same tool, with maximum cross-correlation coefficients averaging 0.9268575, compared to 0.757101 for marks from different tools, validating the effectiveness of 3D shape analysis for tool mark identification. However, limitations, such as a 0.2 mm measurement error and minor differences in correlation coefficients between matching and non-matching toolmarks, suggest the need for further research into improving the error detection capability and optimizing experimental conditions for enhancing impression mark differentiation.

According to the trends in crime occurrence and the characteristics of offenders, there is a reported downward trend in the overall number of crimes, while incidents of sexual violence crimes are on the rise. This increase in sexual violence crimes is presumed to be due to the rise in digital sex crimes and an the change in societal perceptions of sexual violence. Groping-type sexual assault constitutes the largest proportion of the sex crimes. Due to exaggerated media promotion recently, there are concerns that some cases may be misunderstood as applicable to the entire spectrum of incidents, leading to an increased perception that genetic analysis alone can resolve all groping-type sexual assault cases. In this study, the groping-type sexual assault cases with secured comparison samples of the suspects were selectively examined, and the detection rates of short tandem repeat (STR) and Y chromosome STR (Y-STR) DNA types in the surprise groping-type sexual assault cases were analyzed and compared to those of the groping-type sexual assault cases. The detection rates for STR DNA types in groping-type sexual assault cases and surprise groping-type sexual assault cases were similar, at 80% and 70%, respectively: however, the matching rates for the suspects' STR DNA types displayed a significant disparity, with 20% for groping-type sexual assault cases and 1% for surprise groping-type sexual assault cases. Furthermore, the detection rates of Y-STR DNA types for groping-type sexual assault cases and surprise groping-type sexual assault cases were 60% and 30%, respectively, with the matching rates for the suspects' Y-STR DNA types also showing a significant difference of 40% and 7%, respectively. It is more difficult to secure the suspect's DNA type in surprise groping-type sexual assault cases than groping-type sexual assault cases. Therefore, it should be recognized that genetic analysis alone cannot resolve all incidents.

In recent years, the field of forensic genetics has achieved significant technological advancements, with the development of various new techniques that go beyond conventional STR analysis. The analytical product from them has considerable potential for application in criminal investigations and court proceedings, potentially expanding the scope of forensic application. However, despite their scientific potential, these innovations have not been fully integrated into practical settings such as criminal investigations and court proceedings. This study presents the results of a survey conducted among forensic practitioners in South Korea, focusing on the procedural, institutional, and communicative challenges with the legal community they experience in the field. The findings highlight recurring issues, including limited legal admissibility of new methods, a lack of comprehensive and standardized guidelines across forensic processes, and frequent misunderstandings between forensic experts and legal professionals. Respondents emphasized the need to improve the clarity and consistency of forensic reporting, enhance training for practitioners and legal professionals, and establish more effective channels of communication with the legal community. The study concludes that for forensic genetic technologies to lead to meaningful legal outcomes, scientific validity must be accompanied by legal acceptance, practical applicability, and interdisciplinary collaboration.

Synthetic cannabinoids (SCs) are the most abused new psychoactive substances. Although fatal cases related to SCs have been reported in multiple countries, reports on blood concentrations associated with intoxication are limited. Over the past three years, ADB-BUTINACA was detected in two individual fatal cases in Korea. This study presents the blood concentrations of ADB-BUTINACA in these cases. Blood samples were treated with methanol to precipitate proteins. The screening and quantitative analysis were performed by liquid chromatography-tandem mass spectrometry with electrospray ionization in the positive ion mode. Both the limits of detection and the limits of quantification for ADB-BUTINACA were 0.5 ng/mL. Validation results showed good linearity in the range of 0.5-50 ng/mL. ADB-BUTINACA was detected and quantified in cardiac blood and peripheral blood of two individual fatal cases. The determined concentration of ADB-BUTINACA were 33.40 ng/mL and 11.56 ng/mL in cardiac blood, 14.73 ng/mL and 13.75 ng/mL in peripheral blood, respectively. Along with parent form of ADB-BUTINACA, its metabolites were analyzed. In one case ADB-BUTINACA 3,3-dimethylbutanoic acid metabolite was detected and the concentration of the metabolite were 1.44 ng/mL in cardiac blood, 1.96 ng/mL in peripheral blood. Due to lack of previous published reports on blood concentrations of ADB-BUTINACA in fatal cases, toxicological assessment remains challenging. The findings from these authentic cases are expected to serve as an important reference for future forensic investigations.

Animal-related crimes have emerged as a social issue with an increase in the number of pets, and the importance of accurate animal species identification using DNA from crime scene evidence is augmenting. This study investigated the species-specific limitations of universal primers, commonly employed in forensic casework, through a discordant result from a casework sample. Analysis of an evidence sample containing a mixture of human and feline DNA revealed that while 12S sequencing yielded a mixed profile, the Cyt b primer exclusively amplified the human DNA. Subsequent analysis to resolve this discordance demonstrated that the Cyt b primer exhibited a greater number of nucleotide mismatches within its binding region on cat DNA, particularly at the 3' terminus and internal regions, compared to human DNA. This structural incompatibility critically compromised amplification efficiency for the feline DNA template. This finding highlighted a significant forensic limitation, as the use of the Cyt b universal primer alone could lead to the failure of feline DNA detection. To address this issue, the applicability of a feline-specific primer (SFI14-Cat) was validated. This study proves that the Cyt b universal primer can exhibit low amplification efficiency for certain species such as cat. Therefore, it suggests that using a species-specific primer in conjunction with a universal primer is essential for enhancing the accuracy and reliability of forensic analysis for species identification in future animal-related crime cases.

This study aims to experimentally investigate the dynamic operational characteristics and effectiveness of the Electronic Parking Brake(EPB) emergency braking function across various powertrain architectures(Internal Combustion Engine-Gasoline, Diesel; Hybrid Electric Vehicle; Battery Electric Vehicle). The research utilized four popular vehicles: Genesis GV80(Gasoline), Carnival(Diesel), K5 Hybrid(HEV), and IONIQ5(BEV). Two simulated Sudden Unintended Acceleration(SUA) scenarios were performed while maintaining the accelerator pedal at Wide Open Throttle(WOT): 1) continuous EPB activation until the vehicle stops, and 2) repetitive EPB activation and deactivation. The experiments were conducted at the Korea Automobile Testing and Research Institute(KATRI) Proving Ground using a precise data acquisition system integrated with DGPS, IMU, and a CAN logger. Specifically, data representing the response characteristics of the EPB system such as the EPB activation signal, vehicle speed, deceleration, and brake pressure sensor readings were acquired and analyzed in real time. The study results quantitatively characterize the EPB system's emergency braking performance and evaluate its effectiveness as a safety mechanism to mitigate the potential risks of SUA accidents caused by driver pedal misapplication. The findings are expected to provide important foundational data for future vehicle safety system design improvements and related regulatory discussions.