Due to the increasing demand for safety, X-ray equipment is increasingly being used in safety systems. Dual energy X-ray devices are superior to traditional devices because they can achieve estimates of effective atomic numbers that traditional density based segmentation devices cannot provide. In this article, pure material samples are used to obtain system characteristics. The material with linear mass attenuation coefficient can be calculated by using two horizontal images, which provide information about the material. Afterwards, they can be classified as organic and inorganic using effective atomic number methods and clearly identified. In addition, this simple and effective method can also detect organic explosives.





X-ray baggage control devices (XBCD) are increasingly being used at the entrances of critical facilities such as military facilities, airports, and customs. X-ray equipment can display all items inside the package in detail without opening it. They can also detect explosives, drugs, and other threats in a short period of time.

XBCD can be classified based on tunnel size and imaging system. Here, the change in tunnel size is only meaningful in terms of the size suitable for the package to be scanned. Especially with the development of imaging systems, it provides a higher level of security. Single view (SV), dual view (DV), multi view (MV), and sectional view (3D) systems are commonly used today, as shown in Figure 1. SV-XBCD only has one generator and one detector array line, providing a single side view. There are two generators and two independent detector arrays in the DV system. In addition to SV, DV also creates another type of image captured from a side angle; Therefore, the DV system generates two side views simultaneously. Similarly, in a medium voltage system, there are two or more generators and two or more detector lines in order to obtain multiple images of data packets at once. The top product of this product series is a computerized tomography (CT) device that provides 3D images for tomography. As products move towards the high-end of similar products, costs also increase with the improvement of security levels. In this study, the testing, experimentation, and development processes were based on a single view system. Research based on SV can also be directly applied to DV and MV systems using independent generator and detector circuits. The development process is based on a single view system. Research based on SV can also be directly applied to DV and MV systems using independent generator and detector circuits. The development process is based on a single view system. Research based on SV can also be directly applied to DV and MV systems using independent generator and detector circuits.



X-ray detectors are crucial for obtaining optimal data. The radiation generated by the X-ray generator passes through the material and reaches the detector system. Each detector pixel provides a response based on the intensity of the beam reaching the detector. The attenuation of X-rays passing through materials depends on their density, structure, and type. By using the response of the detector, images can be generated and information about the material can be obtained. The information obtained here is numerical data that varies based on the detector pixel A/D resolution (bit depth). Usually, the detector array is perpendicular to the beam generated by the X-ray generator. The object moves continuously on the conveyor line through an electric drum. When a part of the object is aligned with the detector array, take images line by line and combine them to construct the overall image. Assuming the use of a dual energy detector card created by applying a filtering layer between two consecutive detector lines. In this case, obtain both low-energy (LE) and high-energy (HE) datasets simultaneously. The resolution of HE and LE is the same, and the density of pixel images varies according to the detector specifications. The higher the pixel density value, the more meaningful the data obtained. By using HE and LE images, material identification can be achieved through various approaches and methods. Low energy (LE) and high energy (HE) were simultaneously obtained [3], as shown in Figure 2. The resolution of HE and LE is the same, and the pixel density of the image is changed by the detector. The higher the pixel density value, the more meaningful the data obtained. By using HE and LE images, material identification can be achieved through various approaches and methods. The resolution of HE and LE is the same, and the pixel density of the image is changed by the detector. The higher the pixel density value, the more meaningful the data obtained. By using HE and LE images, material identification can be achieved through various approaches and methods.

The substances contained in luggage are generally compounds, alloys, and mixtures. It is crucial to identify and classify them in the XBCD system. The substance with an effective atomic number has been determined, and the system must distinguish explosive materials as the most important threat.

In this study, we focus on SV devices with dual energy capabilities and propose

Estimate and detect organic threats to improve the security level of XBCD. The following section will provide a detailed introduction to the proposed method of material based dual energy system classification and possible threat detection methods.

In 2001, Richard DR Macdonald designed a dual energy X-ray luggage scanning system for airport security checks. He detected organic materials that could pose a threat. Due to the use of an X-ray source, the system can provide a single view of the scanned object in the inspection channel. Using a two-level detector, he obtained material level information about the content of data packets scanned in the tunnel. So, by identifying the effective atomic number of the substance in the packaging, he divided the substance into organic, inorganic, and metal. Afterwards, he detected plastic explosives with low atomic numbers.

Anne Bonnin, Philippe Duvauchelle, Val é rie Kaftandjian, and Pascal Ponard conducted attenuation coefficient decomposition based on mass density and atomic number in a dual energy computed tomography device in 2013. The work on determining effective atomic numbers of different types reviewed the methods and proposed a new effective atomic number method. They used a new method to determine the effective atomic numbers of alcohol, water, nylon, sugar, salt, and silica. Subsequently, explosives such as TNT, C-4, PETN, and RDX were found in the luggage.

In a study conducted by Ji Sung Park and Jong Kyung Kim in 2011, the effective attenuation coefficient, effective atomic number, and density in a dual energy X-ray imaging system were calculated using the source weighting method. This study selected four types of polymer materials. These materials are TNT, acetal, polyethylene, and polyurethane. The deviation between the calculated and experimentally obtained effective atomic numbers and densities of these materials is less than 10. This method has been particularly successful in detecting the effective atomic number and density of objects composed of materials with similar effective atomic numbers.

In 2017, Willem GJ Langeveld obtained the effective atomic number and mass attenuation coefficient for X-ray imaging systems used for truck scanning. Firstly, the effective atomic number is obtained at low energies such as 20-1000 keV, and then the change in effective atomic number is checked by rising to high energies such as 10 MeV. The results of these experiments were effective atomic number formulas developed for cargo inspection systems used at different energy levels.

In 2014, the BAM Federal Institute for Materials Research and Testing conducted a material identification study on cargo containers using dual energy X-ray technology. This study used test pieces composed of low and high atomic number materials, and compared the theoretical calculated atomic number with the experimentally obtained atomic number. According to research findings, distinguishing materials with atomic numbers less than 10 and greater than 46 in high-energy X-ray systems is challenging.