bluuebunny/crossref_metadata_2025 huggingface dataset:
Comprehensive review of kalasalingam technology business incubator startup program and startup olis
Authors: Samuvel Deny John , Sekar R. , Szymański Jerzy R. , Żurek-Mortka Marta , Sathiyanarayanan Mithileysh
Published: November 2024

This research paper offers a comprehensive comparative analysis of two prominent startup incubator programs: the Kalasalingam Technology Business Incubator (KTBI) at Kalasalingam Academy of Research and Education in India, and Startup Olis in Europe. The study explores each program's structure, objectives, and unique contributions to regional and global entrepreneurial ecosystems. KTBI focuses on fostering sustainable innovation by providing financial assistance, state-of-the-art facilities, and dedicated mentorship. Its core mission is to bolster regional economic growth, particularly through initiatives centered on renewable energy and waste management, thus aligning with sustainability goals. In contrast, Startup Olis provides a global platform for emerging businesses across diverse sectors, prioritizing international networking, access to global investment channels, and guidance from industry leaders worldwide. This incubator aims to support scalable ventures with high potential, positioning startups to make a significant mark on international markets. By contrasting these two programs, this paper examines how each contributes to economic development within their respective operational frameworks. The findings highlight the strengths and opportunities inherent in each approach, revealing insights into how localized and globalized incubators shape the growth of startups and influence industry standards. Ultimately, this study underscores the importance of tailored incubation strategies in fostering entrepreneurship and innovation on both a regional and global scale.
Modern anesthesia: A multidisciplinary approach to pain relief
Authors: Godde Kuntal , Mude Gaurav , Barole Nisha , Tenpe Shreya
Published: November 2024

The Division of Vascular Anesthesiology at University of California, Los Angeles (UCLA) handles over 1,000 patients annually, providing specialized care for a range of vascular procedures in an aging society where vascular diseases are prevalent. The division's anesthesiologists are skilled in managing postoperative care for various vascular surgeries, including carotid endarterectomy, atrioventricular (AV) fistula formation, and endovascular treatments for peripheral arterial disease and aortic aneurysms. Advances in stent technology and catheterization allow many procedures to be performed with sedation instead of general anesthesia, reducing risks and hospital stays. Collaboration between vascular anesthesiologists and surgeons ensures optimal patient outcomes. This book discusses advancements in neuraxial, regional, and general anesthesia for vascular surgery, covering topics like vascular anatomy, typical therapies, and anesthesia techniques. The book also addresses preoperative monitoring, postoperative care, and complications. The anesthetic management of patients with high comorbidity and acetylsalicylic acid (ASA) classification undergoing major vascular surgery is emphasized, highlighting the frequent presence of coronary artery disease in this population. Complications related to vascular anesthesia and strategies for managing anesthetic challenges are explored, along with the importance of understanding potential complications, such as malignant hyperthermia and postoperative infections. The choice between local, regional, and general anesthesia is debated, with evidence suggesting that all methods are comparably safe, ultimately depending on patient preference and clinical judgment. The Division of Vascular Anesthesiology at UCLA manages a substantial patient volume, addressing complex vascular conditions prevalent in an aging population. Their expertise spans a range of procedures, from carotid endarterectomy to advanced endovascular interventions. The rapid evolution of stent technology and minimally invasive techniques has significantly reduced the need for general anesthesia, enabling safer, shorter hospital stays. The book details modern approaches in neuraxial, regional, and general anesthesia, emphasizing the importance of preoperative monitoring and postoperative care.
The applicability of lean accounting in enterprises: The case of pulp and paper manufacturing enterprises in Vietnam
Authors: Hung Pham Huy
Published: November 2024

This study investigates the factors affecting the applicability of lean accounting in Vietnam's pulp and paper manufacturing enterprises. The data were surveyed from 298 experts at 145 pulp and paper manufacturing enterprises in Vietnam. Using the structural equation model (PLS-SEM), the study tested 7 hypotheses. The findings suggest that employee knowledge and skills, senior management support, and the availability of lean accounting software positively impact the applicability of lean accounting, whereas the current accounting system and complexity of the manufacturing process negatively impact it. Surprisingly, competitive pressure and customer demand for cost-effective products did not have a significant effect. These results highlight the priority of internal organizational factors over external market pressures in driving lean accounting implementation in this context. The study contributes to contingency theory in management accounting and provides practical insights for Vietnamese enterprises, emphasizing the need to develop internal capacity, ensure management support, and invest in appropriate technology. This study challenges assumptions about the drivers of accounting innovation in emerging markets and emphasizes the importance of a holistic approach to lean accounting implementation. These findings provide the foundation to develop targeted strategies in similar contexts and guide future research directions in the field.
E Evaluation of Ultima InfoSys Site Usability Using Usability Test & System Usability Scale Method
Authors: Putri Clarita , Sutomo Rudi
Published: November 2024

Web Ultima Infosys is one of the websites owned by Multimedia Nusantara University (UMN) which contains a collection of journals majoring in information systems. Based on the results of a survey conducted on the use of the Ultima Infosys website for information system students, many students feel that the appearance of the website is lacking or difficult to use. Especially in journal search and journal submission. Therefore, the usability evaluation of the Ultima Infosys web was carried out. The method used in this research is a usability test and system usability scale (SUS). Where the researcher will evaluate using questionnaires and interviews. The results of the questionnaire were measured using SUS. Based on the results of the evaluation score that has been measured by SUS, the result is a score of 50.25. Knowing that the score is below the average, a recommendation for improvement is made in the form of a recommendation mockup. After re-testing and measuring using SUS, the mockup of the recommendation results got a value above the average of 81,265. Thus, it can be concluded that the mockup of the recommendations proved to be easier to understand and use by users.
Digitalization of control and accounting processes of agricultural enterprises: Risk assessment and management
Authors: Potryvaieva Natalia , Dubinina Maryna , Cheban Yuliia , Syrtseva Svitlana , Luhova Olha
Published: November 2024

The digitalization of control and accounting processes is a requirement of the present day due to the wide opportunities to increase competitiveness and efficiency of activities that it provides to enterprises of any industry. The aim of the study was to analyse the effectiveness of digitalization of control and accounting processes to ensure the achievement of the main objectives of agricultural enterprises. The present study used the method of statistical analysis, descriptive and comparative methods, as well as SWOT and PEST-analysis. The study found that the market for software products for agricultural enterprises continues to grow, with a growth rate of 13.5% per year. It was noted that agricultural enterprises can gain significant advantages with the use of new software products, which will increase the speed, accuracy, transparency, and accessibility of control and accounting processes. The paper examined the capabilities of Enterprise Resource Planning systems, which have a wide range of functionality and mostly meet the needs of large agricultural enterprises. The study also covered the consideration of alternative control and accounting tools that may be more suitable for small and medium-sized enterprises due to their simplicity, targeted focus and low implementation costs. Through an assessment of Ukraine’s agricultural sector, the paper proves the importance of agriculture for the state, which explains the need for close attention to digitalization processes in the sector. BAS AGRO. ERP is considered as an effective system for implementing control and accounting at national agricultural enterprises. As a result of the study, the opportunities and threats, weaknesses and strengths of the digitalization of control and accounting processes in general were noted. It also identified political, economic, social and technological factors that influence these processes in Ukraine
Design and Implementation of an Obstacle Avoidance Aid for the Blind
Authors: Lin Qiruia , Yang Aiwei , Yang Shuangquan , Zhang Zhixia
Published: November 2024

This paper introduces the design and implementation of an obstacle avoidance aid for the blind based on Esp 32 chip. The auxiliary device combines the Internet of Things technology and ultrasonic ranging technology, which can detect and avoid obstacles in the environment in real time, providing a safe and convenient travel guarantee for the blind. This paper first expounds the background and research significance of the project, then analyzes the hardware design and software implementation of the auxiliary device in detail, and conducts experimental verification. Finally, the experimental results are discussed and the directions for improvement are presented.
Identification of Triple Seasonal Autoregressive Models: A Bayesian Approach
Authors: Amin Ayman A.
Published: November 2024

Triple seasonal autoregressive (TSAR) models’ identification is the initial and most-important stage for analyzing time series with three-layers of seasonality in real applications, which has to be efficiently tackled in literature. In this paper, we present an efficient Bayesian identification method to specify the appropriate order for the TSAR models. We first assume the model order is a random variable with a known maximum. By employing different prior distributions for the TSAR order, coefficients and precision, we derive the posterior mass function of the model order in a closed form. Using this derived posterior mass function, we suggest a Bayesian identification method for the TSAR models, which is based on investigating the posterior mass function and accordingly the order value that has the highest posterior probability is chosen as the appropriate TSAR order for time series under study. We validate the identification accuracy of the suggested Bayesian method by executing extensive simulations.
Optimization of Sensor Placement for Gas Leak Detection in Commercial Areas
Authors: Sui Zhewen , Yuan Xiaobing , Ye Fangqi , Jun Ling , Ma Dongliang , Wang Wei
Published: November 2024

This study optimizes sensor placement for gas leak detection in commercial areas through a hybrid Particle Swarm Optimization (PSO) and Computational Fluid Dynamics (CFD) approach. The method improves detection accuracy by simulating gas dispersion and strategically positioning sensors to cover critical zones, adapting to environmental and architectural variations.
Characterization of a Flat-Field Grazing-Incidence XUV Spectrometer
Authors: Schwanda W. , Eidmann K. , Richardson M. C.
Published: November 2024

We describe a XUV spectrometer for the study of dense hot microplasmas at wavelengths between ≈50 and ≈300 Å. It uses a commercially fabricated grazing incidence flat-field reflection grating with 1200 grooves per millimeter. The spectral resolution was optimized by imaging the source on a narrow slit with the help of a curved grazing incidence mirror. The instrument was tested with a laser-produced plasma as a source. The limit of the resolving power due to imaging aberrations of the flat-field grating ranges from 1500 at 50 Å to 3600 at 200 Å and has been achieved with a 5-μm slit. We also measured and calculated the grating efficiencies for the first to fifth diffraction order as a function of wavelength.
Development of iterative algorithms for image reconstruction
Authors: Jiang Ming , Wang Ge
Published: November 2024

The iterative approach is important for computed tomography (CT) and attracting more and more attention with the rapid evolution of computer technology. In this paper, classic results and recent advances on iterative algorithms for image reconstruction are reviewed, with an emphasis on the ART-like and EM-like algorithms in both of their simultaneous and ordered-subset formats. The following issues are discussed: what the computational structures are, under what conditions the algorithms converge, what the final limits are, what the relaxation strategies we have, how the final limits depend on the initial guesses, and so on. In addition, heuristic arguments are given for the SART and EM algorithms for understanding the algorithms. Finally, future research directions are discussed, along with guidelines for practical applications of iterative algorithms.
Image segmentation via fuzzy object extraction and edge detection	and its medical application
Authors: Lin Yao , Tian Jie , He Huiguang
Published: November 2024

A new interactive segmentation method that combines fuzzy connected object extraction and edge detection is proposed. Fuzzy connectedness is a global fuzzy relation, which effectively captures fuzzy "hanging togetherness" of image elements. First, by selecting the seed point, fuzzy connectedness value between each image element and the seed point is computed via dynamic programming. Then, through adjusting the parameter, the different fuzzy connected object could be extracted. Finally, an edge detection method is adopted to detect the object boundary. The algorithm is demonstrated on some medical images: segmentation of knee tissues in CT image and segmentation of brain tissues in MR image. The results show that this method works well for some CT and MR images.
Renewal of Gamma Knife stereotactic radiosurgery after localizer	Frame re-installation
Authors: Tsai J.-S. , Mahajan A. , Borden J. , Rivard M.J. , Engler M.J.
Published: November 2024

A GK plan (GKP) is dosimetrically reproduced following GK Frame (GKF) system failure. A humanoid head Phantom embedded with seven targets was used for the simulation. GKF was attached to the Phantom by 4 pin screws. GKP using CT images solely assigned a single shot to each target for dose coverage. The shots treatment times were based on dose prescription and the skull geometric data (SGD). Afterwards, GKF was adjusted and CT, SGD were repeated. A new GKP was reconstructed by transforming the shots coordinates and treatment times from the original GKF/SGD systems to the new ones. TLDs were inserted into the target sites for dose verifications achieving mutual agreement within 2% clinical cases forced us to do GKF reinstallation: pin loosened in the midway of patient treatment; treatment encountered a helpless GKF collision with the helmet. Each case, a new GKP reproduced by the aforementioned transformations was adopted to keep GK SRS ongoing. In conclusion, if GK SRS was forced to stop due to either a pin attachment failure or GKF collision with helmet, then GKF readjustment and rescan images will not compromise the outcome of a GK SRS treatment.
Multirow detector CT technology: Present and future
Authors: Haller John W. , Westerman Bryan , Vannier Michael W.
Published: November 2024

Multirow CT detectors coupled with 2, 4, 8 and 16 or more simultaneous data acquisition channels are now used in clinical imaging. Furthermore, multirow CT detectors are used with conventional or flat-panel image intensifiers mounted on c-arms that allow 3D CT scanning in rotational angiography or orthopedic interventions. These multirow, multichannel CT systems provide increased speed that translates into the ability to scan larger segments of anatomy more quickly. The principal drawback of multislice/multidector/multichannel CT scanners are increased computational burden, faster data rates, more voluminous data sets, and most importantly, the requirement to use cone beam rather than slice-by-slice reconstruction algorithms. The future of multichannel CT in clinical applications demands improved radiation dose efficiency, isotropic imaging, tailored cone beam reconstruction algorithms, and post-processing visualization of volume image data.
Interstitial laser thermotherapy of a rat liver	adenocarcinoma
Authors: Tranberg K.-G. , Myllymäki L. , Möller P.H. , Ivarsson K. , Sjögren H.O. , Stenram U.
Published: November 2024

The aim of this study was to compare interstitial laser thermotherapy with excision of a liver tumour. A dimethylhydrazine-induced adenocarcinoma was implanted into the left lateral lobe of the rat liver, and treatment was performed 8 days later. Rats were treated with resection of the tumour-bearing lobe or underwent interstitial laser thermotherapy, which was performed at a steady-state temperature of 46°C for 30 min, 3 mm from the tumour margin. The incidence and extent of intraperitoneal spread was smaller after laser thermotherapy than after resection, with no difference in local control. Using inoculation of tumour cell suspensions into the lateral and the median lobes of the liver simultaneously and treating the lateral lobe tumour only, we found that laser thermotherapy reduced take and growth of the untreated tumour in the median lobe indicating that laser thermotherapy may induce immunologic effects. It is concluded that interstitial laser thermotherapy reduces spread of liver tumour as compared to resection. It is suggested that this can be at least partly explained by a laser-induced immunologic effect.
Degree of substitution of chlorin $e_{6}$ on	charged poly- L-lysine chains affects their cellular uptake, localization and	phototoxicity towards macrophages and cancer cells
Authors: Hamblin Michael R. , Miller Jaimie L. , Rizvi Imran , Ortel Bernhard
Published: November 2024

Macromolecular photosensitizer conjugates are under investigation as improved delivery vehicles for dyes used in photodynamic therapy. We have previously described the use of conjugates between photosensitizers such as chlorin $_{e6}$ (c $_{e6}$ ) and poly-L-lysine (pL) chains which are versatile molecular species because the size of the chain can be varied, and the overall charge can be altered from cationic through neutral to anionic. We now report on a series of pL-c $_{e6}$ conjugates in their cationic (native), neutral (acetylated) and anionic (succinylated) forms, where the number of c $_{e6}$ molecules attached to each chain was varied (pL: c $_{e6}$ ratios, 1:4, 1:8, 1:12, and 1:16). The fluorescence emissions were measured in both saline and a disaggregating solvent. We studied two cell lines (an epithelial ovarian cancer, OVCAR-5 and a mouse macrophage, J774) and measured cellular uptake, subcellular localization (by confocal fluorescence microscopy) and phototoxicity. The cellular uptake of the conjugates with four substitution ratios all delivered at 2 μM c $_{e6}$ equivalent concentration showed a maximum at 12 c $_{e6}$ per chain for both cationic and anionic conjugates, but the uptake of the neutral conjugate was proportional to the substitution ratio. The macrophages took up several times more c $_{e6}$ than the ovarian cancer cells. Confocal fluorescence micrographs showed more cellular fluorescence with the lower substitution ratios, and more lysosomal localization with the cationic conjugates. The phototoxicity was much higher for the neutral conjugates. For the cationic and neutral conjugates the 12 c $_{e6}$ per chain was the most effective at killing cells, while for the anionic conjugate it was the 16 c $_{e6}$ per chain. The anionic conjugate was better at killing OVCAR-5 cells, while the cationic was better for J774 cells, and the neutral was approximately the same. These data will help to optimize the parameters to be used in preparing polymeric-photosensitizer conjugates for photodynamic therapy.
X-ray microscopy using alkali-halide crystals
Authors: Kochubey V.I. , Konyukhova Yu.G. , Kochubey D.I.
Published: November 2024

The materials on the basis of alkali-halide crystals for recording the X-ray images are developed. Their spatial resolution is 1 μm, dynamic range of recording is more than 10000. The media allow readout without erasing the image and extended storage of the image. The examples of their use in X-ray microscopy of biological objects are shown.
Selective laser-induced hyperthermia for the treatment of	spontaneous tumors in dogs
Authors: Lucroy Michael D. , Chen Wei R. , Ridgway Tisha D. , Higbee Russell G. , Bartels Kenneth E.
Published: November 2024

Indocyanine green (ICG), with spectral absorption at 800--810 nm, is a chromophore that strongly absorbs and converts near-infrared laser energy into thermal energy. By directly injecting ICG into a tumor, selective tumor hyperthermia during laser irradiation occurs. In this study, 4 dogs with spontaneous tumors were injected in situ with a 0.25% energy. Thermal data were collected from multiple thermocouples placed within the tumor and tumor response was recorded. Tissue heating to ≥ 42°C was observed in all tumors. One dog had a complete remission, one dog had stable disease for 12 weeks, and the other 2 dogs developed progressive disease shortly after treatment. Results from this study demonstrate that chromophore-enhanced laser-induced hyperthermia can effectively and selectively heat canine tumors. However, tumor size and pigmentation of overlying skin are potentially limiting factors to the success of this novel c ancer treatment.
A numerical simulator in VC++ on PC for iterative image	reconstruction
Authors: Li Xiang , Jiang Ming , Wang Ge
Published: November 2024

With the development of computing technology, there is an increasing interest in iterative CT image reconstruction. To study iterative reconstruction algorithms, we have developed a software simulator IterCT in VC++ on PC and made it publicly available on the Internet. In the latest version of the simulator, we have implemented four representative iterative image reconstruction algorithms, which are expectation maximization (EM) method and its ordered-subset version (OSEM), the simultaneous algebraic reconstruction technique (SART) and its ordered-subset version (OSSART). The filtered backprojection method is included as the benchmark.
Electronic planar laminography
Authors: Fazzio R. Shane
Published: November 2024

This paper describes an X-ray imaging architecture, called electronic planar laminography, that utilizes a time delay and integration (TDI) detector to provide laminographic cross-sectional images without recourse to a mechanically moving scintillator. Advantages in system performance and reduced complexity may be achieved in comparison with current scanned-beam laminographic systems. The architecture additionally allows for both two-dimensional radiography and digital reconstruction techniques. Any practical system design must make a number of trade-offs, such as between resolution and throughput. These trade-offs are elucidated through consideration of different design examples.
A description for computed tomography based on sinusoidal	curves
Authors: Liu Julian J. , Watt-Smith Stephen R. , Smith Stephen M.
Published: November 2024

A new description for computed tomography, parallel and equal to Radon transformation but based on sinusoidal functions rather than line integrals, is introduced. This representation contributes an effective algorithm to reduce metal artefacts in reconstruction. Using this method, the information included in the scan data corresponding to the metal implants can be separated from the original projection, an amending method rather than interpolation is therefore provided to reach higher accuracy for reconstruction. The method is with low complexity in computation, and can be combined online with filtered backprojection (FBP), which is the most widely used algorithm in practice, to improve the quality of the reconstructed image. Also, the method has the potential to deal with the artefacts caused by beam hardening and partial volume, and to be developed into a straight reconstruction algorithm based on the sinusoidal representation. Examples are presented for clearer description and demonstration.
Attenuation characteristics of fiberoptic plates for digital	mammography and other X-ray imaging applications
Authors: Vedantham Srinivasan , Karellas Andrew , Suryanarayanan Sankararaman
Published: November 2024

Spatially coherent fiberoptic plates are important components of some charge-coupled device (CCD)-based x-ray imaging systems. These plates efficiently transmit scintillations from the phosphor, and also filter out x-rays not absorbed by the phosphor, thus protecting the CCD from direct x-ray interaction. The thickness of the fiberoptic plate and the CCD package present a significant challenge in the design of a digital x-ray cassette capable of insertion into the existing film-screen cassette holders of digital mammography systems. This study was performed with an aim to optimize fiberoptic plate thickness. Attenuation measurements were performed on nine fiberoptic plates varying in material composition that exhibit desirable optical characteristics such as good coupling efficiency. Mammographic spectra from a clinical mammographic system and an Americium-241 (Am-241) source (59.54 KeV) were used. The spectra were recorded with a high-resolution cadmium zinc telluride (CZT)-based spectrometer and corrected for dead time and pile-up. The linear attenuation coefficients varied by a factor of 3 in the set of tested fiberoptic plates at both mammographic energies and 59.54 keV. Our results suggest that a 3-mm thick high-absorption plate might provide adequate for shielding at mammographic energies. A thickness of 2-mm is feasible for mammographic applications with further optimization of the fiberoptic plate composition by incorporating non-scintillating, high-atomic number material. This would allow more space for cooling components of the cassette and for a more compact device, which is critical for clinical implementation of the technology.
Magnetic resonance digital subtraction angiography (MRDSA) of the	carotid arteries
Authors: Wang Yi , Comunale Joseph , Zimmerman Robert , Prince Martin R.
Published: November 2024

Traditionally magnetic resonance angiography (MRA) of the carotid arteries has been performed with time-of-flight (TOF) methods, which are limited by flow related artifacts. Contrast enhanced MRA using an intravenously administered gadolinium agent can overcome the limitations of TOF MRA. One contrast enhanced MRA method, projection magnetic resonance digital subtraction angiograph (MRDSA), generates time-resolved angiograms in a manner similar to conventional digital x-ray digital subtraction angiography. This 2D MRDSA method was evaluated on 15 patients suspected of carotid artery disease. The image quality and carotid lesion detection of 2D MRDSA were compared with that of the 2D and 3D TOF methods. It was found that 2D MRDSA was superior to both 2D and 3D TOF for diagnosing carotid arterial diseases.
A model-based correction method for beam hardening artefacts in	X-ray microtomography
Authors: Van de Casteele E. , Van Dyck D. , Sijbers J. , Raman E.
Published: November 2024

In micro computer tomography (μCT) and medical CT, X-ray sources are polychromatic. Because of this polychromaticity, Beer's law, which states that the ratio of the attenuated and incoming X-ray beam is exponential with the thickness of the material, is no longer valid. This leads to quantitative and visual errors in the reconstructed images, e.g. cupping and streak artefacts. This paper describes a correction scheme for these artefacts using a bimodal energy model for the source-detector energy spectrum. In essence, this correction procedure is a linearization technique based on a physical model. Results are obtained for different test objects made of combinations of plexiglas, bone, water, and aluminium. They demonstrate the effectiveness of the bimodal model correcting for the beam hardening artefact in two-, and multi-component systems.
Limitation in detecting internal blood vessels using digital X-ray	imaging technique
Authors: Ye Chang , Luo Qingming , Chen Wei R. , Liang Wenxi , Luo Weihua , Zhong Aijun
Published: November 2024

The thickness of the surrounding tissue is a crucial factor in distinguishing the internal blood vessels in digital X-ray images, because enough contrast between vessels and tissues must be generated. We investigated the X-ray attenuations of fat, liver, and muscle tissues, using a digital X-ray imaging system specially designed for small animal studies and the contrast between these tissues and blood vessels. The fat, muscle and the liver tissues were collected from the abdomen, the back and the liver of an adult crossbred swine, respectively. The blood vessels were from mesentery of a Wistar rat. The attenuation coefficients of different tissues and blood vessels of different sizes were measured under different X-ray exposures. Also quantified was the contrast between the tissues and the blood vessels when the diameter of the blood vessel and the thickness of the tissues were the same. The limiting thickness of various tissues at different X-ray exposures was obtained for detecting internal blood vessels of a given size, using the CCD detecting limit, the contrast resolution of the imaging system and the tissue-vessel configuration. The results provided herein could be used for optimization of the parameters of digital X-ray imaging in detecting internal blood vessels.
A half-scan error reduction based algorithm for cone-beam CT
Authors: Zeng Kai , Chen Zhiqiang , Zhang Li , Wang Ge
Published: November 2024

The most popular Feldkamp algorithm for cone-beam image reconstruction assumes a scanning circle, and performs well only with a small cone angle. In this report, we propose a Feldkamp-type algorithm to increase the cone angle by several folds at a radiation dose comparable to that required by the classic Feldkamp algorithm. In our scheme, two half-scans of different radii are used. Then, approximate reconstructions from two half-scans are combined to produce a superior image volume by utilizing a relationship between the half-scan reconstruction error and the scanning locus radius. The merit of this half-scan error reduction based (HERB) algorithm is demonstrated in numerical simulation with the 3D Shepp-Logan phantom.
Algorithm to enhance low contrast features in digital	mammograms
Authors: Gutierrez L. , Alvarez S. , Senor P. , Caselli E. , Pecelis M. , Santiago M.
Published: November 2024

In this paper an algorithm is reported for enhancing low contrast features in mammograms. Some features barely visible or not visible to the naked eye in original images can be observed clearly in the corresponding filtered images along with those features that are readily seen. The main characteristic of the filter is that it allows the simultaneous visualisation of low contrast anatomical features in both the dense mammary gland and the breast periphery. The contribution of the filter to a better interpretation of mammograms is illustrated with examples.
Optimization of a dual-energy imaging Kinestatic Charge Detector	for chest radiography
Authors: Schmithorst Vincent J. , Endorf Robert J. , Kulatunga Sunil , Spelic David C. , DiBianca Frank A. , Rodriguez Carlos , Zeman Herbert D. , Zhu Zeping , Giakos George C.
Published: November 2024

The Kinestatic Charge Detector (KCD) technique of projection radiography shows promise when used for dual-energy imaging, which may be performed either by taking two separate exposures at different kVp settings (the dual-kVp method) or by taking a single exposure with the KCD segmented into a front and back region (the split-detector method), as the higher energy photons will be preferentially absorbed in the back region.

Using computer simulations, we have optimized the dual-energy performance of a segmented KCD using the split-detector method for chest radiography. Theoretical optimization of imaging parameters and determination of contrast resolution were performed by minimizing pixel variances of the basis materials. The expected contrast resolution of the aluminum and plexiglas basis material images was found to be acceptable for purposes of clinical diagnosis. A detector medium of krypton produced better results than xenon at the same density, and the optimal kVp setting was in the range of 120–150 kVp. Preliminary dual-energy images were taken with a small field-of-view split-detector imaging KCD system. The experimentally obtained aluminum and plexiglas basis material pixel variances agree with the theoretical results.
Ordered-subset simultaneous algebraic reconstruction techniques	(OS-SART)
Authors: Wang Ge , Jiang Ming
Published: November 2024

In this paper, we first demonstrate that two ordered-subset simultaneous algebraic reconstruction techniques (OS-SART) can be heuristically derived from the perspective of data rectification. Then, we study the convergence in the framework of our recent work on the OS version of the Landweber scheme. The first OS-SART is the same as the BSSART formula, which is a special case of the OS version of the Landweber scheme. Hence, it converges in the weighted least square sense even in the case of inconsistent data. Both the OS-SART formulas are tested for reconstruction of CT images from practical data.
X-ray study of forensic samples at the SPring-8
Authors: Ninomiya Toshio
Published: November 2024

The capability of synchrotron radiation (SR) is demonstrated by its new applications in the field of criminal investigation. X-ray fluorescence spectrometry with SR provides very high signal-to-noise ratios and showed concentration profiles of trace elements in forensic samples such as illegal drugs and automobile coating chips. The profiles are so unique as to be called "chemical fingerprints" and have become valuable information to investigative authorities. Also, x-ray refraction contrast imaging technique reveals specific structures of materials that can be never observed by optical examination. Such new techniques with SR are making an innovation in police investigations.
Region of interest micro-CT of the middle ear: A practical	approach
Authors: Gea S.L.R. , Decraemer W.F. , Dirckx J.J.J.
Published: November 2024

Computed microtomography (μCT) is an imaging technique that produces virtual slices of an object, based on a set of x-ray images taken while the object is stepwise rotated. The stack of slices is calculated with a backprojection algorithm, it demands that the entire object remains within the x-ray beam for all observed angles. During region-of-interest (ROI) tomography however, one zooms in on a small part of the object. As a consequence the above condition is no longer fulfilled; the input data become incomplete and reconstructed slices are corrupted. In this study we show that, if we are not interested in grayscale values but only in geometrical information, conventional backprojection algorithms still perform well for ROI tomography. We demonstrate this with ROI scans performed on several phantom objects and we show ROI images of the gerbil hearing organ. We found that the resolution could considerably be improved and small details, not visible in a conventional full object scan, can be revealed by a ROI scan. One can use the benefits of ROI-μCT in situations where physical constrains are such that large parts of the object exceed the field of view (FOV), or where a very high magnification is required.
Ultrasonic flaw classification of seafloor petroleum transporting	pipeline based on chaotic genetic algorithm and SVM
Authors: Fei Chunguo , Han Zhengzhi , Liu Qingkun
Published: November 2024

The flaw classification has become one of important tasks in evaluating the seafloor petroleum transporting pipeline integrity. With the aim to classify different kinds of artificial flaws from ultrasonic signals, we develop a novel flaw classification system. In this system we employ wavelet packet decomposition (WPD) to extract the features of ultrasonic signals, employ a new optimization algorithm (chaotic genetic algorithm-CGA) to get rid of redundant and irrelevant features, and employ support vector machine (SVM) classifier to classify the flaws. We use a 5 MHz focal wideband transducer to test four kinds of artificial flaws and collect ultrasonic signals at a 40 MHz sampling rate by a high speed A/D card. Noise cancellation is implemented by adaptive filtering. For comparison purpose, we use different methods as feature selector. Then we compare their results. Through experiment, we can conclude that our system can improve the performance of the SVM classifier for flaws in seafloor pipeline significantly.
Blind noise cancellation in ultrasonic NDE using RPS and ICA:	Computer simulation
Authors: Liu Qingkun , Que Peiwen , Guo Huawei , Song Shoupeng
Published: November 2024

This paper proposes a new denoising method for ultrasonic nondestructive evaluation (NDE) signals using reconstructed phase space (RPS) and independent component analysis (ICA). The proposed method consists of four steps. Firstly a RPS is constructed from the ultrasonic NDE signal. The information about the underlying sources (e.g. ultrasonic signal, noise etc.) acting on the ultrasonic NDE system is contained in this RPS. Second ICA is performed on the RPS to recover all the sources underlying the RPS. Next the desired ultrasonic signal component is selected by decision criterion related to the denoising application and finally is reconstructed to obtain the denoised ultrasonic signal. To validate the proposed method it has been applied to the mixture of simulated ultrasonic NDE signals and Guassian White Noise (WGN). The simulation results show that the signal noise ratio (SNR) of the noise ultrasonic NDE signals can be enhanced greatly using the proposed method.
Laser-photothermal effect on skin tissue – Damage and	recovery
Authors: Chen Wei R. , Bartels Kenneth E. , Liu Hong , Nordquist Robert E.
Published: November 2024

The impact of laser photothermal interactions on tissue damage and recovery was studied. A Ho:YAG laser (2.12 μm) was used to irradiate rabbit skin with different operating parameters. The thermal effect on the skin tissue was examined by measurement of laser-induced lesions and by tissue histology. The lesion size on the surface, the photocoagulation depth and the thermal damage depth were recorded as functions of irradiation parameters. The lesion width and the photocoagulation depth increased with the beam energy while the area of thermal damage remained relatively unchanged. At the fluence levels of 453 J/cm $^{2}$ and 680 J/cm $^{2}$ , laser energy damaged the dermis all the way to the panniculus carnosa, resulting in total dermal collagen photocoagulation, but with little damage to the muscle. Post-treatment histological observation showed a rapid tissue healing and skin regeneration process. The thermal damage on rabbit skin began recovery within a short period and new epithelial growth was clearly seen at day 3. By 7 days, most of the photocoagulated zone was separated from the main body and was replaced by a new layer of epithelium.
Arc based cone-beam reconstruction algorithm using an equal	weighting scheme
Authors: Nett Brian E. , Zhuang Ting-Liang , Leng Shuai , Chen Guang-Hong
Published: November 2024

Conventionally, the FDK algorithm is used to reconstruct images in many imaging systems where cone-beam projections are acquired from a single circular scanning path in a 2π angular range (full scan mode) and has been heuristically extended to a π+fan angle angular range (short-scan mode). In this paper, a new cone-beam reconstruction algorithm is derived for a single arc source trajectory with an equal weighting scheme. This algorithm is derived in the Katsevich framework. Since the single arc does not satisfy Tuy's data sufficiency condition, the resulting algorithm is an approximate reconstruction algorithm. The feature of one-dimensional (1D) shift-invariant filtering in the conventional FDK algorithm is nicely preserved. The new algorithm includes a voxel dependent backprojection step of weighted combinations of 1D Hilbert filtered data, after an initial differentiation operation. In comparing the new algorithm with the standard FDK: the new algorithm intrinsically handles full scan, short scan and super-short scan modes. Numerical simulations have been performed to validate the algorithm, and demonstrate more quantitatively correct density values when reconstructing points away from the central slice. Noise performance was assessed for both the new algorithm and the FDK algorithm using simulated Poisson noise.
Numerical studies on Palamodov and Generalized Feldkamp algorithm	for general cone-beam scanning
Authors: Zeng Kai , Yu Hengyong , Bai Erwei , Wang Ge
Published: November 2024

Recently, the Palamodov algorithm, which was formulated for exact cone-beam reconstruction from data collected along a continuous locus, has been proven to be an excellent approximate algorithm for general cone beam reconstruction. The filtration-backprojection framework of the Palamodov algorithm is efficient for sequential and parallel implementation because its filtration step only involves a 1-D shift-invariant filtering along the tangent direction of the scanning trajectory. On the other hand, the generalized Feldkamp algorithm proposed by Wang et al.~also allows approximate general cone beam reconstruction. In this paper, we report a numerical study comparing these two approximate methods for the cases of helical and saddle curves. In this study, the image quality is evaluated in terms of mean square error (MSE), modulation transform function (MTF), etc. The results demonstrate that the Palamodov algorithm consistently performs similar or better than the generalized Feldkamp algorithm.
The universal concentrations and cancer signs of trace elements in	hair observed by X-ray fluorescence analysis
Authors: Chikawa Jun-ichi , Yamada Kousaku , Akimoto Toshio , Sakurai Hiromu , Yasui Hiroyuki , Yamamoto Hitoshi , Okabe Shinichirou , Ebara Masaaki
Published: November 2024

Homeostasis in concentration of essential elements and its abnormality due to cancer have been observed for single hair samples by X-ray fluorescence analysis using synchrotron radiation. Ca, Br and K are associated with the cellular signal transduction and were found to have two levels of upper and lower concentrations in hair due to gating their ion channels of hair matrix cells where the channels opened by deficiency of the element. The analysis of patient hair from its root to tip revealed that breast cancer accompanied the characteristic long-period decrease from the upper to the lower level of hair [Ca] that had started 8 to 36 months before finding the cancer; the decreasing profiles were unique to cancer as a competitive process between parathyroid hormone PTH and cancer-induced PTH-related protein by comparison with those for non-cancer subjects. It is concluded that breast cancer originates in disturbance of the signal transduction by the high [Ca] in cells. The observed [Br] in hair gave signs for serious diseases such as renal failure. K deficiency was observed for a half of healthy subjects, similarly to the population of hypertension in Japan. Hair from hypertension patients showed K deficiency, unless taking depressor. Most of elements such as Fe, Cu and Zn in hair were indicators for the liver functions of their storage and excretion.
Feldkamp-type reconstruction algorithms for spiral cone-beam CT	with variable pitch
Authors: Zhao Jun , Lu Yang , Jin Yannan , Bai Erwei , Wang Ge
Published: November 2024

Bolus-chasing CT angiography is an important new imaging mode for imaging cardiovascular structures and peripheral vessels. The adaptive bolus-chasing method implies a variable pitch spiral cone-beam CT scan. In this paper, we extend 2D-weighted, 3D-weighted and tilted plane FDK algorithms for variable pitch spiral cone-beam CT. Numerical simulation tests with high pitches and large cone angles are performed. Our results demonstrate that the tilted plane Feldkamp-type reconstruction algorithm shows the highest tolerance to the data incompleteness, the 3D-weighted half-scan FDK algorithm is the best choice for the practical variable pitch cone-beam CT, and the exact reconstruction algorithms perform less satisfactorily when a dataset is incomplete. However, the exact algorithms can be used for high accuracy reconstruction offline if a dataset is complete. Our work may facilitate development of practical variable pitch helical cone-beam CT.
Scheme of computed tomography
Authors: Wei Yuchuan , Yu Hengyong , Hsieh Jiang , Cong Wenxiang , Wang Ge
Published: November 2024

Since Katsevich's work on cone-beam CT in 2002, a series of new reconstruction formulae for cone-beam and fan-beam reconstruction have been published. To understand these new results in a unified way, two schemes were proposed in the literature: one is based on the Radon formula, while the other on the Tuy formula. In the paper, we present a general two-step scheme for parallel-, fan- and cone-beam CT based on the inverse Fourier transform. We first derive parallel-beam formulae and then translate them to the divergent-beam case via a standardized method. This complete framework not only provides a single mechanism for the deduction of most existing CT formulae but also generates new algorithms. Meanwhile, along the development of this new framework some minor flaws are identified and fixed in publications. Additionally, the traditional assumption that an object be compactly supported inside a scanning trajectory is no longer needed.
Metal sheets thickness determined by energy-dispersive X-ray	fluorescence analysis
Authors: Cesareo Roberto , Brunetti Antonio
Published: November 2024

A portable EDXRF equipment was employed to analyze pre-Columbian metals (gold, silver and copper objects) and to determine the thickness of gold in the case of gildings. To this aim, the EDXRF equipment was optimized to detect Cu, Au and Ag, and various methods were developed to determine from X-ray spectra (K-lines ratio) the thickness of the gildings. These methods were first tested to measure gilding compositions and thicknesses of pens and decorative objects. Then pre-Columbian metals were analyzed, such as gold, silver, copper, gilded copper and gilded silver objects from the Royal Tomb of Sipán and from the Museum of Sicán, in the north of Peru.
Investigation of image noise in cone-beam CT imaging due to photon	counting statistics with the Feldkamp algorithm by computer simulations
Authors: Zhang Yan , Ning Ruola
Published: November 2024

Cone beam CT (CBCT) imaging technique has found many applications in medical imaging in recent years since it provides three-dimensional image reconstruction with low contrast detectability and high resolution. In CBCT systems, image noise caused by photon counting statistics plays an important role in image quality by affecting low contrast detection and patient dose. In this paper, we studied image noise caused by photon counting statistics with the Feldkamp's cone beam reconstruction algorithm. A noise model based on photon counting detector was developed to provide the noise distribution in 3D image space and the quantitative relationships between image noise level and various CT parameters, including the exposure level, the number of projections, the reconstruction filter and the detector pixel size. Computer simulations of a spherical water phantom were conducted to test the theoretical model. This work provides the noise spatial distribution in cone-beam CT and its relationship with CBCT parameters. It can also provide local noise information for adaptive de-noising in the future.