Journal articles: 'Iris code'

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Shekar, B. H., S. S. Bhat, and A. Maysuradze. "RELIABILITY INDEX FOR IRIS CODE MATCHING IN IRIS RECOGNITION SYSTEMS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W12 (May 9, 2019): 197–202. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w12-197-2019.

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Abstract. Iris code matching is an important stage of iris biometric systems which compares the input iris code with stored patterns of enrolled iris codes and classifies the code into one of classes so that, the claim is accepted or rejected. Several classifier based approaches are proposed by the researchers to improve the recognition accuracy. In this paper, we discuss the factors affecting an iris classifier’s performance and we propose a reliability index for iris matching techniques to quantitatively measure the extent of system reliability, based on false acceptance rate and false rejection rates using Monte Carlo Simulation. Experiments are carried out on benchmark databases such as, IITD, MMU v-2, CASIA v-4 Distance and UBIRIS v.2.

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HR, GITE, and MAHENDER CN. "IRIS CODE GENERATION AND RECOGNITION." International Journal of Machine Intelligence 3, no. 3 (2011): 103–7. http://dx.doi.org/10.9735/0975-2927.3.3.103-107.

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Şimşek, Buğra, and Nursel Akçam. "Heterogenous Computing on Iris Matching with OpenCL." Applied Mechanics and Materials 850 (August 2016): 129–35. http://dx.doi.org/10.4028/www.scientific.net/amm.850.129.

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This study presents parallelization of Hamming Distance algorithm, which is used for iris comparison on iris recognition systems, for heterogeneous systems that can be included Central Processing Units (CPUs), Graphics Processing Units (GPUs), Digital Signal Processing (DSP) boards, Field Programmable Gate Array (FPGA) and some other mobile platforms with OpenCL. OpenCL allows to run same code on CPUs, GPUs, FPGAs and DSP boards. Heterogeneous computing refers to systems include different kind of devices (CPUs, GPUs, FPGAs and other accelerators). Heterogeneous computing gains performance or reduces power for suitable algorithms on these OpenCL supported devices. In this study, Hamming Distance algorithm has been coded with C++ as a sequential code and has been parallelized a designated method by us with OpenCL. Our OpenCL code has been executed on Nvidia GT430 GPU and Intel Xeon 5650 processor. The OpenCL code implementation demonstrates that speed up to 87 times with parallelization. Also our study differs from other studies, which accelerate iris matching, with regard to ensure heterogeneous computing by using OpenCL.

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Damer, Naser, Philipp Terhorst, Andreas Braun, and Arjan Kuijper. "Efficient, Accurate, and Rotation-Invariant Iris Code." IEEE Signal Processing Letters 24, no. 8 (2017): 1233–37. http://dx.doi.org/10.1109/lsp.2017.2719282.

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Hollingsworth, K. P., K. W. Bowyer, and P. J. Flynn. "The Best Bits in an Iris Code." IEEE Transactions on Pattern Analysis and Machine Intelligence 31, no. 6 (2009): 964–73. http://dx.doi.org/10.1109/tpami.2008.185.

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Liu, Nianfeng, Jing Liu, Zhenan Sun, and Tieniu Tan. "A Code-Level Approach to Heterogeneous Iris Recognition." IEEE Transactions on Information Forensics and Security 12, no. 10 (2017): 2373–86. http://dx.doi.org/10.1109/tifs.2017.2686013.

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Ibgui, L., I. Hubeny, T. Lanz, and C. Stehlé. "IRIS: a generic three-dimensional radiative transfer code." Astronomy & Astrophysics 549 (January 2013): A126. http://dx.doi.org/10.1051/0004-6361/201220468.

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Umer, Saiyed, Bibhas Chandra Dhara, and Bhabatosh Chanda. "Texture code matrix-based multi-instance iris recognition." Pattern Analysis and Applications 19, no. 1 (2015): 283–95. http://dx.doi.org/10.1007/s10044-015-0482-2.

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KMS, Mariya Christeena Vijini, and Kuzhaloli Shanmugan. "Gender Classification From The Iris Code Used For Recognition." International Journal of MC Square Scientific Research 9, no. 1 (2017): 218–29. http://dx.doi.org/10.20894/ijmsr.117.009.001.027.

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Okokpujie, Kennedy, John Abubakar, Samuel John, Etinosa Noma-Osaghae, Charles Ndujiuba, and Imhade Princess Okokpujie. "A secured automated bimodal biometric electronic voting system." IAES International Journal of Artificial Intelligence (IJ-AI) 10, no. 1 (2021): 1. http://dx.doi.org/10.11591/ijai.v10.i1.pp1-8.

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Insecurity, rigging and violence continue to mar electoral processes in developing nations. It has been difficult to enforce security and transparency in the voting process. This paper proposes a secure and automated bimodal voting system. The system uses three security layers, namely, a unique ID code, a token passcode that expires every five minutes and biometrics (iris and fingerprint). A scanner captures the fingerprint and iris of eligible voters. The fingerprint and iris images stored along with the corresponding particulars in a database. The software implemented is a .net managed code in C#. The result of this system shows the system is transparent, fast and fraud-free. The proposed method had a failure to enroll (FTE) and a failure to capture (FTC) of zero.

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Zahedi, Zahedi, and Eka Janitra. "Perancangan Program Aplikasi Deteksi Iris Mata untuk Absensi Karyawan Menggunakan Metode Gabor Wavelet." ComTech: Computer, Mathematics and Engineering Applications 2, no. 1 (2011): 175. http://dx.doi.org/10.21512/comtech.v2i1.2730.

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To take the employees’ absences in a company, a variety of invented tools or technologies are and already used, for example, attendance cards, fingerprints attendance tool, and attendance tool that uses facial recognition. Attendance tool with a facial recognition uses iris recognition of those employees. Iris code has many properties that hard to forge. Thus, the detection and iris recognition is one of the most secure and accurate for identification.

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A. Kumar, Shruthi, and A. Baskar. "Improving the IRIS Recognition Under Different Illumination Using RETINEX Algorithms." International Journal of Engineering & Technology 7, no. 3.6 (2018): 81. http://dx.doi.org/10.14419/ijet.v7i3.6.14943.

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Iris detection and recognition provides more accurate and secure authentication nowadays. The probability of any two people having the same iris pattern is nearly zero, even the identical twins will not have the same iris pattern. The noise and illumination changes, challenges iris recognition correctness and security in authentication process. The available recent pre-processing techniques for iris detection address different type of noise suppression and removing unwanted information in iris, but still it strives with illumination issues. In this paper, we proposed Retinex algorithm for improving iris detection rate. The proposed work comprises into three steps: First we proposed Retinex algorithm in pre-processing, it works based on reflectance value of image and skips the illumination value in image, subsequently feature extraction uses Gabor filter for iris code generation. In conclusion, distance metrics Hamming distance used for iris recognition the proposed work evaluated MMU iris database under different illumination conditions and provides better results.

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Achilli, Andrea, Cinzia Congiu, Roberta Ferri, et al. "SPES3 Facility RELAP5 Sensitivity Analyses on the Containment System for Design Review." Science and Technology of Nuclear Installations 2012 (2012): 1–19. http://dx.doi.org/10.1155/2012/173637.

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An Italian MSE R&D programme on Nuclear Fission is funding, through ENEA, the design and testing of SPES3 facility at SIET, for IRIS reactor simulation. IRIS is a modular, medium size, advanced, integral PWR, developed by an international consortium of utilities, industries, research centres and universities. SPES3 simulates the primary, secondary and containment systems of IRIS, with 1:100 volume scale, full elevation and prototypical thermal-hydraulic conditions. The RELAP5 code was extensively used in support to the design of the facility to identify criticalities and weak points in the reactor simulation. FER, at Zagreb University, performed the IRIS reactor analyses with the RELAP5 and GOTHIC coupled codes. The comparison between IRIS and SPES3 simulation results led to a simulation-design feedback process with step-by-step modifications of the facility design, up to the final configuration. For this, a series of sensitivity cases was run to investigate specific aspects affecting the trend of the main parameters of the plant, as the containment pressure and EHRS removed power, to limit fuel clad temperature excursions during accidental transients. This paper summarizes the sensitivity analyses on the containment system that allowed to review the SPES3 facility design and confirm its capability to appropriately simulate the IRIS plant.

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Han, Ying-Li, and Rae-Hong Park. "Iris Recognition Using the Nonsubsampled Contourlet Transform." International Journal of Pattern Recognition and Artificial Intelligence 29, no. 08 (2015): 1556014. http://dx.doi.org/10.1142/s0218001415560145.

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Biometric information is widely used in user identification system. Because of the unique and invariant properties of the iris through a lifetime, iris recognition is one of the most stable and reliable means in biometric identification. Extracting distinguishable iris features for iris recognition is very important. In this paper, for capturing effective texture features that represent the complex directional structures of an iris image, a new iris recognition method using the nonsubsampled contourlet transform (NSCT) features is proposed. With the shift-invariance, multiscale, and multidirection properties, significant NSCT coefficient features along the radial and angular directions in an iris image can be represented efficiently. Iris segmentation and normalization are considered at first as pre-processing. The modified normalized iris image is obtained from the normalized iris regions for extracting the robust iris features, and then is filtered with the NSCT to obtain the distinct coefficient features in each directional subband. Next, using the NSCT coefficients in each subband, an iris code vector is constructed for iris matching. Comparison of experimental results of the proposed and existing methods with three databases show the effectiveness of the proposed NSCT feature-based iris recognition algorithm, in terms of the three performance measures.

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Mustafa, Raniah Ali, Amal Abdulbaqi Maryoosh, Dena Nadir George, and Waleed Rasheed Humood. "Iris images encryption based on QR code and chaotic map." TELKOMNIKA (Telecommunication Computing Electronics and Control) 18, no. 1 (2020): 289. http://dx.doi.org/10.12928/telkomnika.v18i1.13293.

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Venugopalan, Shreyas, and Marios Savvides. "How to Generate Spoofed Irises From an Iris Code Template." IEEE Transactions on Information Forensics and Security 6, no. 2 (2011): 385–95. http://dx.doi.org/10.1109/tifs.2011.2108288.

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Tapia, Juan E., Claudio A. Perez, and Kevin W. Bowyer. "Gender Classification From the Same Iris Code Used for Recognition." IEEE Transactions on Information Forensics and Security 11, no. 8 (2016): 1760–70. http://dx.doi.org/10.1109/tifs.2016.2550418.

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Diatri Indradewi, I. Gusti Ayu Agung, I. Putu Agung Bayupati, and I. Ketut Gede Darma Putra. "Ekstraksi Ciri pada Citra Iris Menggunakan Gabor 2-D." Majalah Ilmiah Teknologi Elektro 15, no. 1 (2016): 16. http://dx.doi.org/10.24843/mite.2016.v15i01p03.

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Abstrak – Iris merupakan salah satu bagian tubuh manusia yang sering digunakan dalam sistem pengenalan biometrik karena tingkat perbedaannya yang tinggi. Ektraksi ciri merupakan salah satu tahapan yang dilalui dalam pengembangan sistem pengenalan biometrik iris. Tahap ini bertujuan untuk mengekstrak informasi dari citra iris yang telah disegmentasi sehingga dapat digunakan sebagai ciri unik dari iris bersangkutan. Pada paper ini tahap ekstraksi ciri dilakukan dengan menggunakan tapis Gabor 2-D. Tapis tersebut digunakan karena mampu menyediakan representasi gabungan yang optimal dari sinyal dalam domain spasial dan frekuensi. Hasil penerapan tapis Gabor 2-D didemodulasi dengan menggunakan quadrature Gabor 2-D untuk menghasilkan iris code yang dijadikan sebagai informasi pembeda (fitur ciri) iris. Hasil uji coba pada penelitian ini menghasilkan fitur iris terbaik ketika ukuran tapis yang digunakan adalah 33×33. Sudut orientasi yang digunakan untuk fitur real dan imaginary adalah -45º, 0º, 45º, dan 90º. DOI: 10.24843/MITE.1501.03

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V.SatyanarayanaTallapragada, V., and E. G. Rajan. "IRIS Recognition based on Non Linear Dimensionality Reduction of IRIS Code with KPCA and SVM based Classification." International Journal of Computer Applications 44, no. 13 (2012): 42–46. http://dx.doi.org/10.5120/6326-8681.

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Carelli, Mario, Lawrence Conway, Milorad Dzodzo, et al. "The SPES3 Experimental Facility Design for the IRIS Reactor Simulation." Science and Technology of Nuclear Installations 2009 (2009): 1–12. http://dx.doi.org/10.1155/2009/579430.

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IRIS is an advanced integral pressurized water reactor, developed by an international consortium led by Westinghouse. The licensing process requires the execution of integral and separate effect tests on a properly scaled reactor simulator for reactor concept, safety system verification, and code assessment. Within the framework of an Italian R&D program on Nuclear Fission, managed by ENEA and supported by the Ministry of Economic Development, the SPES3 facility is under design and will be built and operated at SIET laboratories. SPES3 simulates the primary, secondary, and containment systems of IRIS with 1 : 100 volume scale, full elevation, and prototypical thermal-hydraulic conditions. The simulation of the facility with the RELAP5 code and the execution of the tests will provide a reliable tool for data extrapolation and safety analyses of the final IRIS design. This paper summarises the main design steps of the SPES3 integral test facility, underlying choices and phases that lead to the final design.

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Chai, Tong-Yuen, Bok-Min Goi, Yong-Haur Tay, and and Zhe Jin. "A New Design for Alignment-Free Chaffed Cancelable Iris Key Binding Scheme." Symmetry 11, no. 2 (2019): 164. http://dx.doi.org/10.3390/sym11020164.

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Iris has been found to be unique and consistent over time despite its random nature. Unprotected biometric (iris) template raises concerns in security and privacy, as numerous large-scale iris recognition projects have been deployed worldwide—for instance, susceptibility to attacks, cumbersome renewability, and cross-matching. Template protection schemes from biometric cryptosystems and cancelable biometrics are expected to restore the confidence in biometrics regarding data privacy, given the great advancement in recent years. However, a majority of the biometric template protection schemes have uncertainties in guaranteeing criteria such as unlinkability, irreversibility, and revocability, while maintaining significant performance. Fuzzy commitment, a theoretically secure biometric key binding scheme, is vulnerable due to the inherent dependency of the biometric features and its reliance on error correction code (ECC). In this paper, an alignment-free and cancelable iris key binding scheme without ECC is proposed. The proposed system protects the binary biometric data, i.e., IrisCodes, from security and privacy attacks through a strong and size varying non-invertible cancelable transform. The proposed scheme provides flexibility in system storage and authentication speed via controllable hashed code length. We also proposed a fast key regeneration without either re-enrollment or constant storage of seeds. The experimental results and security analysis show the validity of the proposed scheme.

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Tamilselvi, S. "A Novel Based Approach for iris code Recognization Using Gabor Filter." IOSR Journal of Electronics and Communication Engineering 4, no. 5 (2013): 32–37. http://dx.doi.org/10.9790/2834-0453237.

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LIU, BO, SIEW-KEI LAM, THAMBIPILLAI SRIKANTHAN, and WEIQI YUAN. "IRIS RECOGNITION OF DEFOCUSED IMAGES FOR MOBILE PHONES." International Journal of Pattern Recognition and Artificial Intelligence 26, no. 08 (2012): 1260010. http://dx.doi.org/10.1142/s0218001412600105.

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In this paper, we introduce a novel iris recognition approach for mobile phones, which takes into account imaging noise arising from image capture outside the depth of field (DOF) of cameras. Unlike existing approaches that rely on special hardware to extend the DOF or computationally expensive algorithms to restore the defocused images prior to recognition, the proposed method performs recognition on the defocused images based on the stable bits in the iris code representation that are robust to imaging noise. To the best of our knowledge, our work is the first to investigate the characteristics of iris features for varying degree of image defocus when the images are captured outside the DOF of cameras. Based on our findings, we present a method to determine the stable bits of an enrolled image. When compared to iris recognition of defocused images that relies on the entire code representation, the proposed recognition method increases the inter-class variability while reducing the intra-class variability of the samples considered. This leads to smaller intersections between the intra-class and inter-class distance distributions, which results in higher recognition performance. Experimental results based on over 15,000 images show that the proposed method achieves an average recognition performance gain of about two times. It is envisioned that the proposed method can be incorporated as part of a multi-biometric system for mobile phones due to its lightweight computational requirements, which is well suited for power sensitive solutions.

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LARBI, Nouar, and Nasreddine TALEB. "A Robust Multi-Biometric System with Compact Code for Iris and Face." International Journal on Electrical Engineering and Informatics 10, no. 1 (2018): 1–13. http://dx.doi.org/10.15676/ijeei.2018.10.1.1.

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Umar, Muhammad Muneer, Amjad Mehmood, Houbing Song, and Kim-Kwang Raymond Choo. "I-Marks: An iris code embedding system for ownership identification of multimedia content." Computers & Electrical Engineering 63 (October 2017): 209–19. http://dx.doi.org/10.1016/j.compeleceng.2017.07.007.

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Maccari, Pietro, Fulvio Mascari, Stefano Ederli, Paride Meloni, and Sandro Manservisi. "ASTEC code DBA analysis of a passive mitigation strategy on a generic IRIS SMR." Annals of Nuclear Energy 156 (June 2021): 108194. http://dx.doi.org/10.1016/j.anucene.2021.108194.

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Al-Zubi, Raed T., Khalid A. Darabkh, and Nayel Al-Zubi. "Effect of Eyelid and Eyelash Occlusions on a Practical Iris Recognition System: Analysis and Solution." International Journal of Pattern Recognition and Artificial Intelligence 29, no. 08 (2015): 1556016. http://dx.doi.org/10.1142/s0218001415560169.

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One of the crucial and inherent issues in a practical iris recognition system is the occlusion that happens due to eyelids and eyelashes. This occlusion increases the complexity and degrades the performance of matching and feature extraction processes. Generally, two types of approaches have been proposed to solve this issue. The first approach requires generating an iris mask that indicates which part of the iris is useful and which others are occluded. However, in the second approach, a fixed region of interest (ROI) within the iris area is selected to avoid the regions of occlusion. In this paper, we experimentally study both approaches but due to the latter characteristic, which is its ability to simplify the matching and feature extraction processes, it has been adopted in our techniques used, specifically for iris segmentation, iris normalization, and feature extraction. Accordingly, for matching and feature extraction, the lower side of the pupillary region (i.e. the innermost 25% of the lower half of the iris ring) is found to be the best ROI. This small area of iris is almost free of eyelids and eyelashes and it contains abundant texture information. Interestingly, this selection of small area helps us in proposing a simple yet efficient technique for feature extraction, called mean-based feature extraction technique (MB-FET). This technique is based on analyzing the local intensity variations. The proposed technique achieves a lower processing burden than other traditional methods such as Fourier or wavelet decompositions (e.g. Gabor wavelet). In most traditional techniques, many parameters (e.g. five parameters for 2D-Gabor filter) must be optimally determined in advance to achieve an accurate feature extraction process. Unfortunately, these parameters may not match various variations in image capturing conditions (e.g. variations in illumination due to change in image capturing distance). Moreover, the basic functions of the traditional methods are fixed in advance (off-line) and do not necessarily match the texture of all irises in the database. However, for our proposed technique MB-FET, there is no need to determine in advance any parameter or basic function. MB-FET dynamically adapts its parameter (only one parameter) with intensity variations. The proposed technique generates a binary iris code, hence a simple and fast matching process is done using the Hamming distance. The experimental results using the CASIA iris database show that the proposed technique achieves promising results for a robust and reliable iris recognition.

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Karad, Avinash, and Shailja Kadam. "MUL-TIBIOMETRIC PATTERN RETRIEVAL USING INDEX CODE TO IMPROVE RESPONSE TIME." International Journal of Engineering Technologies and Management Research 3, no. 4 (2020): 1–13. http://dx.doi.org/10.29121/ijetmr.v3.i4.2016.58.

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In a biometric identification system, the identity corresponding to the input data (probe) is typically determined by comparing it against the templates of all identities in a database (gallery). Exhaustive matching against a large number of identities increases the response time of the system and may also reduce the accuracy of identification. Onaway to reduce the response time is by designing biometric templates that allow for rapid matching, as in the case of Iris Codes. An alternative approach is to limit the number of identities against which matching is performed based on criteria that are fast to evaluate. We propose a method for generating fixed-length codes for indexing biometric databases. An index code is constructed by computing match scores between a biometric image and a fixed set of reference images. Candidate identities are retrieved based on the similarity between the index code of the probe image and those of the identities in the database. The proposed technique can be easily extended to retrieve pertinent identities from multimodal databases. Experiments on a chimeric face and fingerprint bimodal database resulted in an 84% average reduction in the search space at a hit rate of 100%. These results suggest that the proposed indexing scheme has the potential to substantially reduce the response time without compromising the accuracy of identification.

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Ji, Young-Yong, Kun Ho Chung, Wanno Lee, et al. "Development of the IRIS Collimator for the Portable Radiation Detector and Its Performance Evaluation Using the MCNP Code." Journal of the Nuclear Fuel Cycle and Waste Technology(JNFCWT) 13, no. 1 (2015): 55–61. http://dx.doi.org/10.7733/jnfcwt.2015.13.1.55.

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Heinzel, Petr, Jana Kašparová, Michal Varady, Marian Karlický, and Zdeněk Moravec. "Numerical RHD simulations of flaring chromosphere with Flarix." Proceedings of the International Astronomical Union 11, S320 (2015): 233–38. http://dx.doi.org/10.1017/s1743921316000363.

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AbstractFlarix is a radiation–hydrodynamical (RHD) code for modeling of the response of the chromosphere to a beam bombardment during solar flares. It solves the set of hydrodynamic conservation equations coupled with NLTE equations of radiative transfer. The simulations are driven by high energy electron beams. We present results of the Flarix simulations of a flaring loop relevant to the problem of continuum radiation during flares. In particular we focus on properties of the hydrogen Balmer continuum which was recently detected by IRIS.

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Kagawade, Vishwanath C., and Shanmukhappa A. Angadi. "A new scheme of polar Fast Fourier Transform Code for iris recognition through symbolic modelling approach." Expert Systems with Applications 197 (July 2022): 116745. http://dx.doi.org/10.1016/j.eswa.2022.116745.

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da Silva Santos, J. M., J. de la Cruz Rodríguez, J. Leenaarts, et al. "The multi-thermal chromosphere." Astronomy & Astrophysics 634 (February 2020): A56. http://dx.doi.org/10.1051/0004-6361/201937117.

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Context. Numerical simulations of the solar chromosphere predict a diverse thermal structure with both hot and cool regions. Observations of plage regions in particular typically feature broader and brighter chromospheric lines, which suggests that they are formed in hotter and denser conditions than in the quiet Sun, but also implies a nonthermal component whose source is unclear. Aims. We revisit the problem of the stratification of temperature and microturbulence in plage and the quiet Sun, now adding millimeter (mm) continuum observations provided by the Atacama Large Millimiter Array (ALMA) to inversions of near-ultraviolet Interface Region Imaging Spectrograph (IRIS) spectra as a powerful new diagnostic to disentangle the two parameters. We fit cool chromospheric holes and track the fast evolution of compact mm brightenings in the plage region. Methods. We use the STiC nonlocal thermodynamic equilibrium (NLTE) inversion code to simultaneously fit real ultraviolet and mm spectra in order to infer the thermodynamic parameters of the plasma. Results. We confirm the anticipated constraining potential of ALMA in NLTE inversions of the solar chromosphere. We find significant differences between the inversion results of IRIS data alone compared to the results of a combination with the mm data: the IRIS+ALMA inversions have increased contrast and temperature range, and tend to favor lower values of microturbulence (∼3−6 km s−1 in plage compared to ∼4−7 km s−1 from IRIS alone) in the chromosphere. The average brightness temperature of the plage region at 1.25 mm is 8500 K, but the ALMA maps also show much cooler (∼3000 K) and hotter (∼11 000 K) evolving features partially seen in other diagnostics. To explain the former, the inversions require the existence of localized low-temperature regions in the chromosphere where molecules such as CO could form. The hot features could sustain such high temperatures due to non-equilibrium hydrogen ionization effects in a shocked chromosphere – a scenario that is supported by low-frequency shock wave patterns found in the Mg II lines probed by IRIS.

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FORSBACH, RALF. "Health Policy in Twentieth-Century Europe." Contemporary European History 15, no. 3 (2006): 417–21. http://dx.doi.org/10.1017/s0960777306003390.

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Iris Borowy and Wolf D. Gruner eds., Facing Illness in Troubled Times: Health in Europe in the Interwar Years 1918–1939 (Frankfurt am Main: Peter Lang, 2005), 424 pp., €64.00 (hb), ISBN 363119486.Horst H. Freyhofer The Nuremberg Medical Trial: The Holocaust and the Origin of the Nuremberg Medical Code, Studies in Modern European History 53 (New York: Peter Lang, 2005), 209 pp., €30.00 (pb), ISBN 0820467979.Ulrike Lindner Gesundheitspolitik in der Nachkriegszeit. Großbritannien und die Bundesrepublik Deutschland im Vergleich, Veröffentlichungen des Deutschen Historischen Instituts London 57 (Munich: R. Oldenbourg Verlag, 2004), 581 pp., €64.00 (hb), ISBN 3486200143.

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Cheng, Yaosong, Yuanning Liu, Xiaodong Zhu, and Shuo Li. "A Multiclassification Method for Iris Data Based on the Hadamard Error Correction Output Code and a Convolutional Network." IEEE Access 7 (2019): 145235–45. http://dx.doi.org/10.1109/access.2019.2946198.

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Yuan, Chunhui, and Haitao Yang. "Research on K-Value Selection Method of K-Means Clustering Algorithm." J 2, no. 2 (2019): 226–35. http://dx.doi.org/10.3390/j2020016.

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Among many clustering algorithms, the K-means clustering algorithm is widely used because of its simple algorithm and fast convergence. However, the K-value of clustering needs to be given in advance and the choice of K-value directly affect the convergence result. To solve this problem, we mainly analyze four K-value selection algorithms, namely Elbow Method, Gap Statistic, Silhouette Coefficient, and Canopy; give the pseudo code of the algorithm; and use the standard data set Iris for experimental verification. Finally, the verification results are evaluated, the advantages and disadvantages of the above four algorithms in a K-value selection are given, and the clustering range of the data set is pointed out.

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Sulavko, Alexey Е., and Alexander А. Khramov. "Biometric authentication method based on cepstral characteristics of external ear echograms and biometrics-to-code neural converter." Journal Of Applied Informatics 17, no. 1 (97) (2022): 69–82. http://dx.doi.org/10.37791/2687-0649-2022-17-1-69-82.

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Open biometric images (fingerprint, iris, face) are "in sight" and therefore compromised in the natural environment. In this work, it is proposed to use data on the internal structure of the outer ear obtained using echography as biometric images. The individual characteristics of the ear canal of subjects are hidden from direct observation and cannot be copied by photographing. The proposed authentication method is based on cepstral analysis of echograms of the ear canal using neural network biometrics to code converters, trained in accordance with GOST R 52633.5. The neural network biometrics-code converter allows you to associate a user's cryptographic key or password with his biometric image. This is a shallow neural network of one or two layers of neurons, which is configured to generate a key specified during training when an image of a known user arrives, and when an unknown image arrives at its inputs, generate a random code with high entropy. At the entrance to this network, cepstral signs of echograms were received. To apply the method in practice, you need a special device that combines a headphone with a sound-proof housing and a microphone. The results obtained can be called optimistic EER = 0.031 (FAR = 0.001 at FRR = 0.23). The use of neural network converters biometrics-code showed a relatively higher percentage of errors in comparison with multilayer neural networks and the naive Bayes classification scheme, however, neural network biometrics to code converters allows you to implement authentication in a protected mode. This means that the subject's biometric data will be protected from compromise at the stages of storage, execution and transmission via communication channels.

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Bose, Souvik, Vasco M. J. Henriques, Luc Rouppe van der Voort, and Tiago M. D. Pereira. "Semi-empirical model atmospheres for the chromosphere of the sunspot penumbra and umbral flashes." Astronomy & Astrophysics 627 (July 2019): A46. http://dx.doi.org/10.1051/0004-6361/201935289.

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Context. The solar chromosphere and the lower transition region are believed to play a crucial role in the heating of the solar corona. Models that describe the chromosphere (and the lower transition region), accounting for its highly dynamic and structured character are, so far, found to be lacking. This is partly due to the breakdown of complete frequency redistribution (CRD) in the chromospheric layers and also because of the difficulty in obtaining complete sets of observations that adequately constrain the solar atmosphere at all relevant heights. Aims. We aim to obtain semi-empirical model atmospheres that reproduce the features of the Mg II h&k line profiles that sample the middle chromosphere with focus on a sunspot. Methods. We used spectropolarimetric observations of the Ca II 8542 Å spectra obtained with the Swedish 1 m Solar Telescope and used NICOLE inversions to obtain semi-empirical model atmospheres for different features in and around a sunspot. These were used to synthesize Mg II h&k spectra using the RH1.5D code, which we compared with observations taken with the Interface Region Imaging Spectrograph (IRIS). Results. Comparison of the synthetic profiles with IRIS observations reveals that there are several areas, especially in the penumbra of the sunspot, where most of the observed Mg II h&k profiles are very well reproduced. In addition, we find that supersonic hot down-flows, present in our collection of models in the umbra, lead to synthetic profiles that agree well with the IRIS Mg II h&k profiles, with the exception of the line core. Conclusions. We put forward and make available four semi-empirical model atmospheres. Two for the penumbra, reflecting the range of temperatures obtained for the chromosphere, one for umbral flashes, and a model representative of the quiet surroundings of a sunspot.

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ROMDHANE, L. B., B. AYEB, and S. WANG. "ON COMPUTING THE FUZZIFIER IN ↓FLVQ: A DATA DRIVEN APPROACH." International Journal of Neural Systems 12, no. 02 (2002): 149–57. http://dx.doi.org/10.1142/s0129065702001060.

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Clustering is an important research area that has practical applications in many fields. Fuzzy clustering has shown advantages over crisp and probabilistic clustering, especially when there are significant overlaps between clusters. Most analytic fuzzy clustering approaches are derived from Bezdek's fuzzy c-means algorithm. One major factor that influences the determination of appropriate clusters in these approaches is an exponent parameter, called the fuzzifier. To our knowledge, no theoretical reason leading to an optimal setting of this parameter is available. This paper presents the development of an heuristic scheme for determining the fuzzifier. This scheme creates close interactions between the fuzzifier and the data set to be clustered. Experimental results in clustering IRIS data and in code book design required for image compression reveal a good performance of our proposal.

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Duma, Iuliana, Alin Constantin Murariu, Aurel Valentin Bîrdeanu, and Radu Nicolae Popescu. "Comparative Study on Remaining Life Assessment of a Pressure Vessel, Working in Severe Conditions, Based on Results of Metallographic Replicas and Creep Tests." Advanced Materials Research 1164 (June 23, 2021): 67–75. http://dx.doi.org/10.4028/www.scientific.net/amr.1164.67.

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The paper presents and compares the results on the reliability and remaining life assessment of a reactor (coxing box) from a petrochemical plant. The reactor shell is made of 16Mo5 (W1.5423) steel, with a thickness of 25 mm, plated with 3 mm thick X6CrAl13 (W1.4002) stainless steel. The assessment was made in two steps. For preliminary remnant life assessment, specifications of section VII of the ASME code was used followed by iRiS‑Thermo expert system. Further, experimental creep and metallographic replica analysis were performed. Results comparison of the two methods applied revealed a reduction of the preliminary estimated remaining live obtained using metallographic replica analysis. Based on the results obtained, the possibility to extend the service duration of the coxing box in the safety condition, using current process parameters, with of 20.000 hours was highlighted.

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Joshi, Reetika, Brigitte Schmieder, Guillaume Aulanier, Véronique Bommier, and Ramesh Chandra. "The role of small-scale surface motions in the transfer of twist to a solar jet from a remote stable flux rope." Astronomy & Astrophysics 642 (October 2020): A169. http://dx.doi.org/10.1051/0004-6361/202038562.

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Context. Jets often have a helical structure containing ejected plasma that is both hot and also cooler and denser than the corona. Various mechanisms have been proposed to explain how jets are triggered, primarily attributed to a magnetic reconnection between the emergence of magnetic flux and environment or that of twisted photospheric motions that bring the system into a state of instability. Aims. Multi-wavelength observations of a twisted jet observed with the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory and the Interface Region Imaging Spectrograph (IRIS) were used to understand how the twist was injected into the jet, thanks to the IRIS spectrographic slit fortuitously crossing the reconnection site at that time. Methods. We followed the magnetic history of the active region based on the analysis of the Helioseismic and Magnetic Imager vector magnetic field computed with the UNNOFIT code. The nature and dynamics of the jet reconnection site are characterised by the IRIS spectra. Results. This region is the result of the collapse of two emerging magnetic fluxes (EMFs) overlaid by arch filament systems that have been well-observed with AIA, IRIS, and the New Vacuum Solar Telescope in Hα. In the magnetic field maps, we found evidence of the pattern of a long sigmoidal flux rope (FR) along the polarity inversion line between the two EMFs, which is the site of the reconnection. Before the jet, an extension of the FR was present and a part of it was detached and formed a small bipole with a bald patch (BP) region, which dynamically became an X-current sheet over the dome of one EMF where the reconnection took place. At the time of the reconnection, the Mg II spectra exhibited a strong extension of the blue wing that is decreasing over a distance of 10 Mm (from −300 km s−1 to a few km s−1). This is the signature of the transfer of the twist to the jet. Conclusions. A comparison with numerical magnetohydrodynamics simulations confirms the existence of the long FR. We conjecture that there is a transfer of twist to the jet during the extension of the FR to the reconnection site without FR eruption. The reconnection would start in the low atmosphere in the BP reconnection region and extend at an X-point along the current sheet formed above.

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Avram, Camelia, Jose Machado, and Adina Aştilean. "Hardware Passwords Manager Based on Biometric Authentication." Engineering Proceedings 6, no. 1 (2021): 31. http://dx.doi.org/10.3390/i3s2021dresden-10085.

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This paper presents a portable passwords manager which has a two-stage biometric-based access procedure. Data security using biometric methods was chosen as a variant of reduced complexity but was very effective in preventing cyber theft. The implementation of biometrics for the purpose of identification in high-security systems has become essential with the evolution of technology and the spike in identity theft. Unlike passwords or IDs, a biometric feature is an identifier that cannot be lost, stolen, or replicated, which provides biometric authentication systems with an increased level of security. During the first accessing step, the 3DPassManager portable device measures the heartbeat and uses fingerprint and iris features to realize a unique biometric-based authentication. While the specific characteristics of fingerprint and iris features are integrated to ensure that the person using the device is the rightful owner, the pulse is utilized to verify if previously acquired static images are not used. During the second accessing step, a password is generated based on fingerprint details, valid only for a small-time interval. The fingerprint is stored in a secret key with a 1024-bit length. Once access is allowed, the passwords are made available through an extension installed on the web browser. The device is the size of a cigarette pack and communicates with the PC by scanning a QR code. It is safe and was previously tested for dictionary and brute force attacks.

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Vial, J. C., P. Zhang, and É. Buchlin. "Some relationships between radiative and atmospheric quantities through 1D NLTE modeling of prominences in the Mg II lines." Astronomy & Astrophysics 624 (April 2019): A56. http://dx.doi.org/10.1051/0004-6361/201834249.

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Context. With more than four years of IRIS observations, and in order to avoid building customized diagnostics for each observation, it is useful to derive some simple relations between spectra and physical quantities. This is even more useful for the k and h lines of Mg II, which require complex non-local-thermodynamic-equilibrium NLTE treatments. Aims. The aim of this work concerning prominences is to correlate observable spectral features in h and k lines of Mg II to physical quantities such as the density and the emission measure (EM) in the same way as similar correlations have been obtained in the hydrogen lines. In this way, and within approximations done on some parameters such as temperature, it is possible to build pixel by pixel an IRIS map of the above-mentioned quantities. Methods. In order to simplify and shorten the modeling, we chose to compute one-dimensional (1D) isothermal and isobaric models that are treated with the PROM7 NLTE code available at MEDOC (IAS). We built a set of models with large ranges of temperature, pressure, and thickness. At all altitudes considered, we paid attention to the exact computation of the incident radiation. Then we compared the emergent Mg II h and k intensities with the corresponding hydrogen and electron densities and EMs. Results. From the NLTE computation, we derive correlations between the k and h emergent intensities on one hand and the densities and EM on the other hand. With some assumptions on the temperature, we obtain a unique relation between the k (and h) intensities and the EM that should be useful for deriving either the hydrogen and electron densities or the effective thickness of an observed prominence. Conclusions. From NLTE modeling, we have provided a relationship between observable integrated intensities of the Mg II resonance lines and prominence plasma EM, which will contribute to a first-order analysis of long time series of spectroscopic observations, for example, with IRIS. We anticipate building more complex relations between the profiles and other plasma quantities.

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MOWLAVI, ALI ASGHAR, and MAJED YAZDANI. "CALCULATION OF ISODOSE CURVES FOR CCA AND CCB CONCAVE EYE APPLICATORS." International Journal of Modern Physics B 25, no. 29 (2011): 3905–10. http://dx.doi.org/10.1142/s0217979211101272.

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BEBIG Ruthenium-106 ophthalmic plaques have been used for treatment of uveal melanoma, retinoblastoma, melanoma of the iris and other special applications for more than 30 years. The plaques consist of a thin film of Ru-106, a beta emitter encapsulated in pure silver. Simulations of small concave applicators CCA and CCB, manufactured by Bebig, were performed using Monte Carlo MCNP4C code which allows for description of the applicator (geometry and materials) in detail. Electrons are emitted from the 106 Ru nuclei isotropically with initial energy randomly sampled from the corresponding Fermi spectra and with initial positions uniformly distributed on the radioactive layer. In this work, relative doses were calculated in soft tissue phantom near the active layer. Isodose curves for CCA and CCB eye applicators were determined. Our calculated data agrees well with the measured phantom data reported in literature.

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Schlegel, Robert E., A. Ravi Ravindram, Shivakumar Raman, and Hank Grant. "Wireless Telephone-Hearing Aid Electromagnetic Compatibility Research at the University of Oklahoma." Journal of the American Academy of Audiology 12, no. 06 (2001): 301–8. http://dx.doi.org/10.1055/s-0042-1745612.

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AbstractA multiphase study examining electromagnetic compatibility (EMC) between wireless digital telephones and hearing aids has been under way at the University of Oklahoma EMC Center since May 1995. In a phase 1 clinical study involving 68 hearing aid wearers, interference varied significantly by telephone technology, hearing aid type, and hearing loss characteristics. More than 80 percent of the tests resulted in either no interference or a detection threshold distance less than 1 meter. Metallic shielding of the units yielded positive results. Various elements of phase 2 involved instrument-based tests of hearing aid interference using telephones in a sound-isolation chamber and radio frequency signals in a waveguide, along with clinical studies of speech-to-interference ratios, all leading to the development of standards of measurement and performance criteria for telephone emissions and hearing aid immunity. Results to date confirm that bystander interference is of less concern than user interference, which is the focus of continuing research. Abbreviations: ASC = Accredited Standards Committee, AMPS = advanced mobile telephone system, ANSI = American National Standards Institute, BTE = behind the ear, CDMA = code division multiple access, CIC = completely in the canal, EMC = electromagnetic compatibility, GSM = Global System for Mobile Communications, IRIL = input referenced interference level, IRIS = input referenced interference spectrum, IS = international standard, ITC = in the canal, ITE = in the ear, J-STD = “J” standard, NAL = National Acoustic Laboratories, PCS = personal communication services, RF = radio frequency, TDMA = time division multiple access

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Levens, P. J., and N. Labrosse. "Modelling of Mg II lines in solar prominences." Astronomy & Astrophysics 625 (May 2019): A30. http://dx.doi.org/10.1051/0004-6361/201833132.

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Context. Observations of the Mg II h and k lines in solar prominences with IRIS reveal a wide range of line shapes from simple non-reversed profiles to typical double-peaked reversed profiles, and with many other possible complex line shapes. The physical conditions responsible for this variety are not well understood. Aims. Our aim is to understand how physical conditions inside a prominence slab influence shapes and properties of emergent Mg II line profiles. Methods. We compute the spectrum of Mg II lines using a one-dimensional non-LTE radiative transfer code for two large grids of model atmospheres (isothermal isobaric, and with a transition region). Results. The influence of the plasma parameters on the emergent spectrum is discussed in detail. Our results agree with previous studies. We present several dependencies between observables and prominence parameters which will help with the interpretation of observations. A comparison with known limits of observed line parameters suggests that most observed prominences emitting in Mg II h and k lines are cold, low-pressure, and optically thick structures. Our results indicate that there are good correlations between the Mg II k line intensities and the intensities of hydrogen lines, and the emission measure. Conclusions. One-dimensional non-LTE radiative transfer codes allow us to understand the main characteristics of the Mg II h and k line profiles in solar prominences, but more advanced codes will be necessary for detailed comparisons.

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Mateiu, Horia, Traian Fleşer, and Alin Constantin Murariu. "The Assessment of Remaining Life of Chemical Reactor Exposed to Creep and Fatigue." Key Engineering Materials 399 (October 2008): 51–59. http://dx.doi.org/10.4028/www.scientific.net/kem.399.51.

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The paper presents an application according the reliability and remining life assessment of the reactor (coxing box) from a petrochemical plant, after failure in welding joint of plated shell from W1.5423 (16Mo5) steel with 25 mm thickness, plated with W1.4002 stainless steel with 3 mm thickness. The reactor failure it has associated with initial flaws from welding process, which have accelerated remaining life exhaustion. The assessment made in two steps. It has used VII section of ASME code specifications and iRiS-Thermo expert system for preliminary remaining life assessment. Concomitantly, it was performed the experimental creep and thermal fatigue testing. The program results have defined creep and thermal fatigue exhaustion and its remaining life at common creep-fatigue action, in condition of safety exploitation. It was emphasized the possibility of use an extra 40,000 hours of rehabilitated reactor in the safety condition of normal parameters.

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JANG, Hyun-Do, and Sang-Jun LEE. "Nomenclatural review of new names proposed by Yong No Lee." Korean Journal of Plant Taxonomy 52, no. 1 (2022): 1–23. http://dx.doi.org/10.11110/kjpt.2022.52.1.1.

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This review provides information about the nomenclatural status of new names proposed by Dr. Yong No Lee, in accordance with the current International Code of Nomenclature for Algae, Fungi, and Plants. A total of 363 designations and names were proposed from 16 books and 95 papers by Dr. Yong No Lee, and their status was examined, with 161 designations found to be not validly published. In addition, 13 later isonyms and ten later homonyms were found by this review. However, 173 names were found to be legitimate. All designations and names were categorized according to their nomenclatural status and were listed by place of publication. The nomenclatural statuses of six designations or names, including “Iris odaesanensis,” were not confirmed in this review. It is therefore necessary to undertake further research into the nomenclatural status of these taxa by examining their types and published protologues.

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Petrovic, Bojan. "Preliminary Evaluation of the Scale MAVRIC Code and FW-CADIS Method for Efficient Scoping of the Radiation Field Throughout the IRIS Containment." Nuclear Technology 168, no. 2 (2009): 438–43. http://dx.doi.org/10.13182/nt09-a9222.

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Ohmaid, Hicham, S. Eddarouich, A. Bourouhou, and M. Timouya. "Comparison between SVM and KNN classifiers for iris recognition using a new unsupervised neural approach in segmentation." IAES International Journal of Artificial Intelligence (IJ-AI) 9, no. 3 (2020): 429. http://dx.doi.org/10.11591/ijai.v9.i3.pp429-438.

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Un système biométrique d'identification et d'authentification permet la reconnaissance automatique d'un individu en fonction de certaines caractéristiques ou caractéristiques uniques qu'il possède. La reconnaissance de l'iris est une méthode d'identification biométrique qui applique la reconnaissance des formes aux images de l'iris. En raison des motifs épigénétiques uniques de l'iris, la reconnaissance de l'iris est considérée comme l'une des méthodes les plus précises dans le domaine de l'identification biométrique. L'algorithme de segmentation proposé dans cet article commence par déterminer les régions de l'œil à l'aide d'une approche neuronale non supervisée, après que le contour de l'œil a été trouvé à l'aide du bord de Canny, la transformation de Hough est utilisée pour déterminer le centre et le rayon de la pupille et de l'iris. . Ensuite, la normalisation permet de transformer la région de l'iris circulaire segmenté en une forme rectangulaire de taille fixe en utilisant le modèle de feuille de caoutchouc de Daugman. Une transformation en ondelettes discrètes (DWT) est appliquée à l'iris normalisé pour réduire la taille des modèles d'iris et améliorer la précision du classificateur. Enfin, la base de données URIBIS iris est utilisée pour la vérification individuelle de l'utilisateur en utilisant le classificateur KNN ou la machine à vecteur de support (SVM) qui, sur la base de l'analyse du code de l'iris lors de l'extraction des caractéristiques, est discutée.

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Lo Frano, R., and G. Forasassi. "Buckling of Imperfect Thin Cylindrical Shell under Lateral Pressure." Science and Technology of Nuclear Installations 2008 (2008): 1–8. http://dx.doi.org/10.1155/2008/685805.

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The strength of thin shells, under external pressure, is highly dependent by the nature of imperfection. This paper investigates buckling behaviour of imperfect thin cylindrical shells with analytical, numerical, and experimental methods in conditions for which, at present, a complete theoretical analysis was not found in literature. In general, collapse is initiated by yielding, but interaction with geometrical instabilities is meaningful, in that imperfections reduce the load bearing capacity by an amount of engineering significance also when thickness is considerable. The aim of this study was to conduct experiments that are representative of buckling, in the context of NPP applications as, for instance, the IRIS (international reactor innovative and secure) and LWR steam generator (SG) tubes. At Pisa University, a research activity is being carried out on the buckling of thin walled metal specimen, with a test equipment (and the necessary data acquisition facility) as well as numerical models were set up by means FEM code. The experiments were conducted on A-316 test specimens, tubes with and without longitudinal welding. The numerical and experimental results comparison highlighted the influence of different types of imperfections on the buckling loads with a good agreement between the finite-element predictions and the experimental data.

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Journal articles on the topic 'Iris code'

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