2,253 results on '"ridges"'
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2. Eggshell Nanosheets: Synthesis, Properties, and Their Forensic Applications in Latent Friction Ridges Development.
- Author
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Sankhla, Mahipal Singh, Verma, Rohit Kumar, Nagar, Varad, Sharma, Vaibhav, Jain, Divyansh, Sharma, Anuj, Kumar, Sanjay, Awasthi, Kumud Kant, Pandey, Harsh, and Pandey, Kamakshi
- Subjects
- *
EGGSHELLS , *FORENSIC fingerprinting , *NANOSTRUCTURED materials , *POWDERS , *WASTE products , *SCANNING electron microscopy , *STRUCTURAL shells - Abstract
Since waste materials are used to identify, individualize, and evaluate evidence like fingerprints, palmprints, footprints, etc. that are found at a crime scene, they have a substantial impact on the field of forensic science. Many waste powders have recently been employed in fingerprint recognition. Nanosheets made up of eggshells have been put forward as an application in friction ridge development. Eggshell is a biochemical substance made up of chemical compounds like calcium carbonate, which is considered as a waste product. For the formation of an eggshell nanosheet (ESN), shells are dried and crushed into a fine powder and to get this powder in the form of a nanosheet, the Ball milling technique is used. The synthesis of pure ESN is confirmed by Scanning Electron Microscopy (SEM) and X‐ray diffraction (XRD) techniques. The size of nanosheets ranged from 30 to 90 nm as shown in SEM images. Developed powder is then used for the application of fingerprint development and it provides excellent results on all porous, non‐porous, and semi‐porous surfaces. Thus, this newly synthesized ESN powder can be used as a significant powder method in latent fingerprint technology. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Biometric Inheritance Pattern Synthesis and Features’ Extraction
- Author
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Sharma, Vimlesh, Gupta, Yogesh Kumar, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Joshi, Amit, editor, Mahmud, Mufti, editor, and Ragel, Roshan G., editor
- Published
- 2023
- Full Text
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4. Quartzite Ridges in Southwestern Nigeria
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Fashae, Olutoyin Adeola, Olusola, Adeyemi, Obateru, Rotimi, Faniran, Adetoye, Migoń, Piotr, Series Editor, Faniran, Adetoye, editor, Jeje, Lawrence kosoko, editor, Fashae, Olutoyin A., editor, and Olusola, Adeyemi O., editor
- Published
- 2023
- Full Text
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5. Bio‐Inspired Instability‐Induced Hierarchical Patterns Having Tunable Anisotropic Wetting Properties.
- Author
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Nagashima, So, Suzuki, Ko, Matsubara, Seishiro, and Okumura, Dai
- Subjects
RESIDUAL stresses ,WETTING ,CONTACT angle ,ELASTOMERS - Abstract
This paper introduces a method for the bottom‐up fabrication of bio‐inspired hierarchical patterns having tunable anisotropic wetting properties. The method exploits the surface instability of bilayers comprising a gold nanofilm attached to a substantially prestretched elastomer substrate. Upon film formation, highly aligned wrinkles spontaneously form on the surface owing to the surface instability driven by the compressive residual stress in the film. Thereafter, uniaxial compressive strain is applied to the film by prestretch relaxation of the substrate, which generates an array of high‐aspect‐ratio ridges on the surface. Consequently, hierarchical patterns comprising unidirectionally aligned ridges covered with wrinkles are obtained. Water droplets placed on surfaces having the aforementioned hierarchical patterns show direction‐dependent contact angles, resulting in elongated shapes, which indicates the presence of anisotropic wetting properties. The magnitude of wetting anisotropy can be tuned by simple control of the applied compressive strain and film thickness. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
6. Topographic effects on buoyancy driven flows along the slope.
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Berntsen, Jarle, Darelius, Elin, and Avlesen, Helge
- Subjects
CENTER of mass ,CONTINENTAL slopes ,WATER masses ,MODELS & modelmaking ,DENSITY currents - Abstract
The flow and descent of dense water masses formed in shallow regions of the ocean is an important leg in the global overturning circulation. The dense overflow waters tend to flow along the continental slopes as geostrophically balanced gravity plumes, but may be steered downslope by canyons and ridges cross-cutting the slopes. In that process, entrainment and mixing will be greatly enhanced. Ilicak et al. (Ocean Model 38:71–84, 2011) propose a parameterization to include the effects of corrugations in large scale models by increasing the vertical mixing locally. We re-visit the problem using the terrain-following Bergen Ocean Model and a DOME-inspired idealized topography. It is shown that the applied corrugations can move the core of the plume 800 m down the slope, while enhanced mixing raises the center of gravity by only 1–200 m. The overall effect of a corrugation is hence to lower the center of gravity, suggesting that the parameterization proposed by Ilicak et al. (Ocean Model 38:71–84) will act in the wrong vertical direction, if used on its own. A comparison of two bottom drag parameterizations, show that a parameterization consistent with a no-slip boundary condition is needed to correctly represent Ekman drainage, and that the Ekman drainage contribution to plume descent is comparable to that of the corrugation. Ridges are more effective in steering dense water downward than canyons, and we compare the dynamics between the two settings to explain the difference. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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7. Linear convergence of the subspace constrained mean shift algorithm: from Euclidean to directional data.
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Zhang, Yikun and Chen, Yen-Chi
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EUCLIDEAN algorithm , *KERNEL functions - Abstract
This paper studies the linear convergence of the subspace constrained mean shift (SCMS) algorithm, a well-known algorithm for identifying a density ridge defined by a kernel density estimator. By arguing that the SCMS algorithm is a special variant of a subspace constrained gradient ascent (SCGA) algorithm with an adaptive step size, we derive the linear convergence of such SCGA algorithm. While the existing research focuses mainly on density ridges in the Euclidean space, we generalize density ridges and the SCMS algorithm to directional data. In particular, we establish the stability theorem of density ridges with directional data and prove the linear convergence of our proposed directional SCMS algorithm. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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8. Start-up transient analysis using CWT and ridges for broken rotor bar fault diagnosis.
- Author
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Halder, Sudip, Bhat, Sunil, and Dora, Bimal
- Subjects
- *
ROTORS , *FAULT diagnosis , *SQUIRREL cage motors , *WAVELET transforms , *TRANSIENT analysis , *FINITE element method - Abstract
This paper introduces a reliable approach based on start-up transient analysis using continuous wavelet transform (CWT) and ridges (local maxima in spectrogram) for early detection of a broken rotor bar fault in an induction motor. The main goal is to track the evolution of the fault frequency components related to rotor bar breakage in the starting current of the motor. The CWT has been used to limit the current signal to a specific frequency band (suitable for observing the dynamics of fault frequencies), and ridges in the time–frequency domain are computed to observe the fault feature related to rotor bar breakage. The suggested work's key benefit is the precise visualization of the fault feature in the time–frequency plane to detect the rotor fault. A quantitative analysis of fault severity has also been presented. A finite element model (FEM) of the machine is simulated in ANSYS 2D workbench to investigate the fault. The proposed method is validated with simulated data, and to demonstrate the efficacy of the method, various simulation scenarios with varying load torques have been presented. Finally, the diagnosis approach is validated using an accessible public data set corresponding to the aforementioned fault. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
9. Bio‐Inspired Instability‐Induced Hierarchical Patterns Having Tunable Anisotropic Wetting Properties
- Author
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So Nagashima, Ko Suzuki, Seishiro Matsubara, and Dai Okumura
- Subjects
anisotropic wetting ,ridges ,surface instability ,thin films ,wrinkles ,Physics ,QC1-999 ,Technology - Abstract
Abstract This paper introduces a method for the bottom‐up fabrication of bio‐inspired hierarchical patterns having tunable anisotropic wetting properties. The method exploits the surface instability of bilayers comprising a gold nanofilm attached to a substantially prestretched elastomer substrate. Upon film formation, highly aligned wrinkles spontaneously form on the surface owing to the surface instability driven by the compressive residual stress in the film. Thereafter, uniaxial compressive strain is applied to the film by prestretch relaxation of the substrate, which generates an array of high‐aspect‐ratio ridges on the surface. Consequently, hierarchical patterns comprising unidirectionally aligned ridges covered with wrinkles are obtained. Water droplets placed on surfaces having the aforementioned hierarchical patterns show direction‐dependent contact angles, resulting in elongated shapes, which indicates the presence of anisotropic wetting properties. The magnitude of wetting anisotropy can be tuned by simple control of the applied compressive strain and film thickness.
- Published
- 2023
- Full Text
- View/download PDF
10. Following Paths of Maximum Catalytic Activity in the Composition Space of High‐Entropy Alloys.
- Author
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Plenge, Mads K., Pedersen, Jack K., Mints, Vladislav A., Arenz, Matthias, and Rossmeisl, Jan
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CATALYTIC activity , *MACHINE learning , *RENEWABLE energy sources , *RENEWABLE energy transition (Government policy) , *ELECTROLYTIC reduction , *OXYGEN reduction - Abstract
The search for better and cheaper electrocatalysts is vital in the global transition to renewable energy resources. High‐entropy alloys (HEAs) provide a near‐infinite number of different alloys with approximately continuous properties such as catalytic activity. In this work, the catalytic activity for the electrochemical oxygen reduction reaction as a function of molar composition of Ag‐Ir‐Pd‐Pt‐Ru HEA is treated as a landscape wherein it is shown that the maxima are connected through ridges. By following the ridges, it is possible to navigate between the maxima using a modified nudged elastic band (NEB) model integrated in a machine learning NEB algorithm. These results provide a new understanding of the composition space being similar to an evolutionary landscape. This provides a possible new search and design strategy for new catalysts in which the composition of known catalysts can be optimized by following ridges rather than exploring the whole alloy composition space. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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11. The Height of Chitinous Ridges Alone Produces the Entire Structural Color Palette.
- Author
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Raut, Hemant Kumar, Ruan, Qifeng, Finet, Cédric, Saranathan, Vinodkumar, Yang, Joel K.W., and Fernandez, Javier G.
- Subjects
STRUCTURAL colors ,MORPHOLOGY ,BUTTERFLIES - Abstract
The colorful wings of butterflies result from the interaction between light and the intricate chitinous nanostructures on butterflies' scales. This study demonstrates that just by reproducing the chitinous ridges present in butterfly scales (i.e., without any other secondary structure), the entire color palette is achieved. This result is achieved using a new methodology based on the controlled reproduction of parts of the biological structure of complex chitinous systems using their native chemistry, enabling the isolation of different features' contributions. Here the contribution of the ridges and their variations as producing and modulating color hue is isolated. The results suggest that complicated butterfly scales may be non‐ideal solutions for producing color when multifunctionality is not considered. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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12. Pre-Construction predictions of the Loads from large Ice Ridges Interacting with the Confederation Bridge Piers.
- Author
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Timco, G.W.
- Subjects
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BRIDGE foundations & piers , *FINITE element method , *CONFEDERATION of states , *OFFSHORE structures ,CONFEDERATION of Canada, 1867 - Abstract
During the design phase of the Confederation Bridge in Canada, the Canadian government Public Works and Government Services Canada asked the National Research Council (NRC) of Canada to provide information on ice loads from large ridges using a wide range of predictive technologies. The NRC put together a team that looked at loads from several sources including analytical models, physical model tests, finite element models, discrete particle models, and full-scale data. The ice loading scenario was an extreme first-year ridge loading one of the bridge piers. A large number of analytical models were used and the load components were separated into those from the consolidated layer, the sail, and the keel. An upper bound prediction from this approach gave a value of 16 MN on a pier, but the assumptions that were used to arrive at this value did not match observed behavior in the physical and numerical studies of the program. Physical model tests indicated that the loads could be 10.5 MN with a load of 7.3 MN from the keel and 3.2 MN from the consolidated layer and sail. A finite element analysis indicted a range of predicted values of 10 MN to 12 MN depending upon the assumptions used. A discrete particle analysis predicted load values from 2.2 MN to 9.5 MN depending upon the assumptions used in describing the stiffness of the ridge. A review of full-scale measurements on lighthouses and ships suggested that the loads could range from 7.3 MN to 10.4 MN. These predicted values compare to the highest load measured on the Confederation Bridge over a twenty-year span of just over 8 MN. This paper outlines the approaches used for this prediction study and their resulting predictions. It shows the value of using multiple approaches for load predictions for offshore structures in ice-covered waters. • Predictions of ice ridge loads on the Confederation Bridge piers. • Analytical, Physical Modelling and Numerical approaches for ice ridge loading. • Comparison to measured loads on bridge piers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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13. The Estimation of Inter-Channel Phase Synchronization of EEG Signals in Patients with Traumatic Brain Injury Before and Post the Rehabilitation
- Author
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Tolmacheva, Renata A., Obukhov, Yury V., Zhavoronkova, Ludmila A., Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Bhattacharjee, Debotosh, editor, Kole, Dipak Kumar, editor, Dey, Nilanjan, editor, Basu, Subhadip, editor, and Plewczynski, Dariusz, editor
- Published
- 2021
- Full Text
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14. Analogs of Ridge Skin and Papillary Patterns in the Nature and the Significance of Their Study for Forensic Science and Forensic Examination
- Author
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Sh. N. Khaziev
- Subjects
ridged skin ,ridges ,fingerprints ,dermatoglyphics ,identification ,forensics ,papillary pattern ,striped pattern, tiger skin ,forensic examination ,Social pathology. Social and public welfare. Criminology ,HV1-9960 - Abstract
Patterns similar to the papillary patterns of human fingers, palms, and soles can be found in living and inanimate nature. Studying such patterns and the structure of the ridged skin of humans and primates in comparison with similar formations on other objects is necessary for forensic science, forensic traceology, fingerprinting, and biometric identification. The article analyzes the history of the study of the ridged skin of humans, primates, and other animals by forensic scientists, zoologists, anthropologists, and representatives of other sciences.The author proposes systemizing and classifying the information about the analogs of papillary patterns and ridged skin on such grounds as the genus and type of carrier objects, relief structure, degree of comparability with the papillary pattern of human hands and soles.The article presents the most indicative varieties of analogs of papillary patterns in mammals, birds, fish, insects, corals, plants, and fungi. The author has studied and systemized structural features of the striped pattern of the skin of tigers and zebras, crests and stripes in corals, stripes and ridged patterns in fish. The data obtained on ridge formations, which are similar in structure and shape to the papillary patterns of human fingers and palms, will help to avoid expert errors during fingerprinting examination or erroneous placement of images of such formations in forensic databases.Knowledge of the structural features and properties of striped patterns of skins of specially protected wild animals, as well as the crest surface of paleontological museum objects, should be used for their identification by photo and video images in cases of embezzlement, smuggling, illegal hunting, and illegal trafficking.
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- 2022
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15. Using relief nouns in the english dictionaries
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Begmatovich, Farmonov Bekzod
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- 2021
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16. A Survey of Latent Fingerprint Indexing and Segmentation Based Matching
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Singh, Harivans Pratap, Dimri, Priti, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Kolhe, Mohan L., editor, Tiwari, Shailesh, editor, Trivedi, Munesh C., editor, and Mishra, Krishn K., editor
- Published
- 2020
- Full Text
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17. EFFICIENCY OF MECHANIZED COMB TECHNOLOGY OF SOIL TREATMENT PREPARATION FOR SOWING SUGAR BEETS.
- Author
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Tesliuk, Viktor, Baranovsky, Viktor, Lukach, Vasyl, Ikalchyk, Mykola, Kushnirenko, Anatoly, and Kulyk, Vasyl
- Subjects
- *
SUGAR beets , *SOWING , *TILLAGE , *CULTIVATORS - Abstract
Mechanized technology of spring tillage, which is used in farms of Ukraine for sowing sugar beets on moist and heavy soils, provides multiple passes of pre-sowing machines due to significant winter soil moisture, leading to significant compaction of its surface layers. This reduces the yield of root crops, increases the economic costs of their production and the emergence of environmental negative consequences. The aim of the work is to increase the yield and reduce the economic costs of the process of sowing sugar beets by developing advanced technology of pre-sowing soil preparation with the division of operations on autumn ridge formation and spring pruning of their tops followed by sowing seeds in the formed ridges. The results of the experimental research of the offered technology of preparation of soil are shown and indicators of efficiency of its application in comparison with control are defined. It is established that minimization of spring pre-sowing tillage allows sowing seeds at an earlier date with sufficient uniformity of seed sowing depth in the ridge (square depth of deviation -- up to 2.3%), which leads to increased growing season and increasing vegetative productivity of plants or root yield. The maximum final yield of root crops in areas sown by the advanced technology was 4.909 tons per hectare, which is approximately 16% more than the yield (4.241 tons/hectare) of the control area. The obtained results confirm the positive efficiency of the proposed technology of pre-sowing tillage for sowing beets on soils heavy in mechanical composition. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
18. Procedure of reducing solanine in potato tubers
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Starovoitova, O. A., Starovoitov, V. I., Manokhina, A. A., and Chaika, V. A.
- Published
- 2021
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19. تحليل الظروف الجوية المرافقة لأليام المطيرة في السنة الجافة2007/2008 والسنة الرطبة 2003/2002في األردن.
- Author
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محمد زيتون, علي المقبل, and صفاء الشياب
- Published
- 2022
20. Efficient fingerprint features for gender recognition.
- Author
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Jalali, Shima, Boostani, Reza, and Mohammadi, Mokhtar
- Abstract
After a crime scene, accurate gender recognition by fingerprint analysis is vital for detectives because precise gender recognition highly limits the search space. For extracting high quality features from fingerprint images, each image should be preprocessed. The preprocessing stages include segmentation, normalization, filtering, binarization, and thinning. Next, different features from various domains are elicited from each image. The suggested features are ridge count, minutiae points, discrete cosine transform, entropy, local binary pattern and ridge thickness valley thickness ratio features. Each feature and the combination of features for one and five fingers are separately applied to six efficient classifiers for gender recognition. The best result implies 99% accuracy with the ridge count for all five fingers. A combination of features for each finger in the best case provides 91% gender recognition accuracy. The combination of our candidate features for each finger is compared to singular value decomposition (SVD), discrete wavelet transform (DWT), and the combination of SVD and DWT. Our results statistically (p value < 0.05) outperform the compared methods. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
21. Genetic inheritance of fruit traits and seed coat colour in bitter gourd (Momordica charantia)
- Author
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P GANGADHARA RAO, TUSAR KANTI BEHERA, ANILABH DAS MUNSHI, GOGRAJ SINGH JAT, and BOOPALAKRISHNAN G
- Subjects
Bitter gourd ,Fruit curviness ,Genetic inheritance ,Momordica charantia ,Ridges ,Seed coat colour ,Agriculture - Abstract
The present experiment on genetic inheritance of fruit traits (ridgeness, tubercles and curviness) and seed coat colour of bitter gourd (Momordica charantia L.) was carried out at experimental farm of Division of Vegetable Science, ICAR-IARI, New Delhi in 2014–16. The study provides genetic information for development of new varieties and hybrids as per the consumer preference. The classical Chi-square (χ2) test was used to estimate the inheritance pattern of qualitative traits using six generations (P1, P2, F1, F2, BC1P1 and BC1P2; F3 generation as F2 for seed coat colour). Inheritance of fruit traits like continuous ridges (Cr: in DBGS-54 × DBGS-2 and DBSS-54 × Pusa Vishesh; χ2 = 0.09; P = 0.76 and χ2 = 0.50; P = 0.48, respectively), tubercles (Tb: DBGS-54 × DBGS-2 and DBSS-54 × Pusa Vishesh; χ2 = 0.50; P = 0.48and χ2 = 0.01; P = 0.92, respectively), fruit curviness (Cf: DBGS-54 × DBGS-2; χ2 = 0.02; P = 0.89) and black seed coat colour (Bs: Pusa Aushadhi × DBGS-54 and DBGS-54 × DBGS-2; χ2 = 0.73; P = 0.39 and χ2 = 0.02; P = 0.89, respectively) were found to be controlled by single dominant gene. Simple inheritance of these fruit traits will enable the bitter gourd breeder to incorporate these traits in hybrids. The black seed coat colour will act as a morphological marker for hybrid seed purity test too.
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- 2022
- Full Text
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22. The Average Shape of Sea Ice Ridge Keels.
- Author
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Metzger, Andrew T., Mahoney, Andrew R., and Roberts, Andrew F.
- Subjects
- *
SEA ice , *ICE fields , *SONAR , *DIAMOND crystals , *SOIL freezing - Abstract
Through analysis of over 64,000 ridge profiles identified from moored upward‐looking sonars, we identify a well‐defined average shape of pressure ridge keels that is concave or cusped, not triangular as widely assumed in other literature. On the basis of this average shape, we put forward a new, dimensional‐definition, of a pressure ridge cross‐section that follows a negative exponential form and allows an average pressure ridge cross section to be constructed with knowledge or choice of a single parameter. The horizonal asymptote of the profile represents the draft of the "background" ice in which the ridge is embedded. The draft of this background ice scales with keel depth and is typically greater than can be accounted through thermodynamic growth, indicating that ridges tend to be embedded in fields of mechanically thickened rubble. Using a variational ridge model we simulated keel shapes for a range of ridge building conditions. The model results agree well with the observations and indicate the cusped shape of an average ridge profile arises from the varying angle of horizontal shear in the ice cover when ridges form. The modeling results also explain the elongated tail of the area draft distribution of the pack. Plain Language Summary: Through analysis of over 64,000 sea ice ridge profiles identified from upward‐looking sonars, we identify a well‐defined average shape for ridge keels. The shape of keels tends to be concave and not triangular as commonly cited in existing literature. Because of this result, we put forward a new description of an average ridge cross‐section that has a concave shape. This new definition allows an average ridge cross section to be constructed with a value for a single parameter. It was observed the draft of the "background" ice, the ice cover on either side of a ridge, scales with keel depth and, on average, is greater than can be accounted through natural thickening of the ice due to freezing alone, indicating ridges tend to be embedded in rubble fields; fields of ice that result from ice that was fractured and compiled by movement of the ice cover. Using a mathematical sea ice ridge model, we simulated keels for a range of ridge building conditions. The modeling results agree with observations and indicate the concave shape of the average ridge profile arises from variations in the horizontal shearing of the ice cover when ridges form. Key Points: Paramters that define an average pressure ridge scale to one anotherOn average, sea ice ridge keels tend to have a concave (cusped) shape that scales to the draft of the background iceA varying angle of horizontal shear in the ice cover is the cause of the cusped shape of an average ridge keel [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Long‐Term Morphodynamics of a Coupled Shelf‐Shoreline System Forced by Waves and Tides, a Model Approach.
- Author
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Nnafie, A., de Swart, H. E., Falqués, A., and Calvete, D.
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SAND waves ,SHORELINES ,TIDES ,WATER waves - Abstract
Sand ridges, with length scales of several km, are prominent features of the seafloor landscape of many sandy continental shelves. Knowledge about the extent to which these ridges influence the large‐scale (i.e., decadal and kilometer scales) morphodynamic evolution of the adjacent shoreline and vice versa (shelf‐shoreline morphodynamic coupling) is limited. The present work aims at quantifying this coupling by using a coupled nonlinear shelf‐shoreline model forced by tides and different wave conditions. Model results show that the presence of sand ridges on the shelf creates longshore non‐uniform wave patterns, which act as a forcing template for the morphodynamic development of the shoreline. The shelf‐shoreline coupling primarily works one way, meaning that the morphodynamic evolution of the shelf affects the evolution of the shoreline. When wave propagation is predominantly aligned with the long axis of the shelf ridges, the forced shoreline undulations are so prominent, that they affect the shelf morphology (significant two‐way coupling). Moreover, for those waves, the longshore spacing of the ridges is strongly imprinted on the shoreline morphology. Weaker shoreline undulations develop for waves that propagate more across the ridges and the weakest for time‐varying wave conditions with large variability in their angles of propagation. Model results compare fairly well with observations. Physical mechanisms underlying the different morphodynamic responses of the coupled shelf‐shoreline system to different wave conditions are also given. Plain Language Summary: Huge sand ridges (scales of 10 kilometers) are observed on the seafloor of many sandy continental shelves. Knowledge about the effects of these ridges on the evolution of the adjacent shoreline is limited. The present study addresses these effects using a coupled shelf‐shoreline model. Model results show that, when waves propagate along the sand ridges, the latter cause the development of large shoreline undulations, which have the same longshore spacing as the ridges. The shoreline undulations are weak for time‐varying wave conditions with large wave directionality (i.e., large variability in their wave angles). Wave climates with a large wave directionality, as is the case of the Belgium coast, are expected to have weak shoreline undulations compared with wave climates with a small wave directionality (e.g., wave climate of Fire Island) Key Points: Ridges on the shelf provide a forcing template for the large‐scale (decadal and kilometer scales) morphodynamic development of the shorelineWhen waves propagate along ridges, strong shoreline undulations develop, which feed back to the shelf morphology (two‐way coupling)For time‐varying waves with large variability in their angles of propagation, shoreline undulations are small [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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24. Le "prolongement naturel" et le plateau continental étendu arctique du Canada: coopérer pour donner sens au droit, à la science et aux faits.
- Author
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BARTENSTEIN, KRISTIN and GOSSELIN, LAURE
- Abstract
Résumé: En mai 2019, le Canada a présenté sa soumission concernant son plateau continental étendu arctique à la Commission des limites du plateau continental. La délinéation des plateaux continentaux étendus, conformément à la Convention des Nations Unies sur le droit de la mer, résulte d'interprétations dans lesquelles s'entrelacent arguments scientifiques et juridiques à l'égard d'une situation géophysique singulière. Cet article examine la manière dont le Canada a composé avec la triple interprétation juridique, scientifique et factuelle à travers une étude articulée autour de la notion de "prolongement naturel." Sont mis en relief les défis interprétatifs, mais aussi les opportunités que le Canada a saisies en participant au dégagement de consensus scientifiques et juridiques au soutien de la délinéation qu'il propose. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
25. Multipurpose Attachment System for Ploughing, Spraying and Creating Ridges in Agriculture
- Author
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Sawant Sachin, Godase Vaishnavi, Ghundre Saurabh, Ghurye Aditya, Ghule Chaitrali, Ghume Abhishek, and Giri Sanika
- Subjects
agriculture ,ploughing ,spraying ,ridges ,multifunctional attachments ,Environmental sciences ,GE1-350 - Abstract
Small-scale farmers would be benefited from versatile attachments that may be used to automate chores that would typically need both human and animal efforts in terms of cost and labor. Farming is made simpler and faster by mechanization. For practically every task in agriculture, there is a machine accessible. Various machines are used to do all the steps right from preparing the soil to crop harvesting and beyond, thus making chores not only easier to complete but also do them effectively. Modern agricultural equipment is more expensive and out of the reach of the majority of farmers with little resources. Due to their low-income levels, most farmers are unable to invest in the purchase of significant machinery. Given the aforementioned circumstances, it is necessary to create a piece of machinery that can be used for a variety of tasks, including ploughing, creating ridges, and Spraying. In order to address this issue the present paper reports the fabrication of a novel machine with multifunctional attachments to carry out above mentioned tasks efficiently and economically.
- Published
- 2023
- Full Text
- View/download PDF
26. Spoofing free fingerprint image enhancement
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Khan, H. Mohamed and Venkadesh, P.
- Published
- 2023
- Full Text
- View/download PDF
27. The complex construction history of Poverty Point's timber circles and concentric ridges.
- Author
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Hargrave, Michael L., Clay, R. Berle, Dalan, Rinita A., and Greenlee, Diana M.
- Subjects
- *
EXCAVATION , *WORLD Heritage Sites , *MAGNETIC anomalies , *PREFABRICATED buildings , *TIMBER , *POVERTY - Abstract
The Poverty Point World Heritage Site (ca. 1700–1100 BC) is one of the world's unique fisher-hunter-gatherer sites. Magnetic gradient surveys of ca. 25 ha together with magnetic susceptibility studies, coring, targeted excavations, and stratigraphic investigations have yielded important new discoveries about aspects of the construction history of the site's monumental concentric ridges and massive plaza. Thirty-six timber circles with diameters ranging up to 62 m are located in and near the plaza. The closely spaced posts and circle clusters suggest extensive rebuilding. Ridge construction components have been identified through the presence of distinctive linear magnetic anomalies. The components provide evidence for ridge single and multistage construction, repairs, and possible deconstruction. The innermost two ridges are inferred to be the earliest, as they exhibit evidence for longer, more complex construction histories than the outer ridges. We now see that Poverty Point's construction history is both more complex and more accessible than previously thought. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
28. Blanket Bogs
- Author
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Lindsay, Richard, Finlayson, C. Max, editor, Milton, G. Randy, editor, Prentice, R. Crawford, editor, and Davidson, Nick C., editor
- Published
- 2018
- Full Text
- View/download PDF
29. Aadhaar Card Voting System
- Author
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Srinivasu, Lingamallu Naga, Rao, Kolakaluri Srinivasa, Xhafa, Fatos, Series editor, Chaki, Nabendu, editor, Cortesi, Agostino, editor, and Devarakonda, Nagaraju, editor
- Published
- 2018
- Full Text
- View/download PDF
30. Identification and analysis of topographic features of Aizawl City
- Author
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Beingachhi, Bobby and Zothansanga, David
- Published
- 2019
- Full Text
- View/download PDF
31. Creating terracotta panels through grayscale image processing and robotic hotwire cut molds.
- Author
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Jovanović, Marko, Vučić, Marko, Stojaković, Vesna, Tepavčević, Bojan, and Raković, Mirko
- Subjects
- *
DIGITAL image processing , *GRAYSCALE model , *IMAGE processing , *TERRA-cotta , *IMAGE compression , *ARCHITECTURAL details - Abstract
This research presents a method for fabricating relief terracotta panels, utilizing polystyrene molds shaped by robotic hotwire cutting. A crucial aspect of this work is the use of grayscale images as input for generating toolpaths for hotwire cutting, bridging the gap between digital image processing in computer graphics and the physical creation of architectural elements. The process integrates computational tools with fabrication constraints and material properties to generate an integrated design approach. Utilizing computational tools, we generate toolpaths that translate grayscale images into tangible tile patterns. These patterns are formed by ridges, designed to accurately depict the grayscale images while ensuring functional tiling. The methodology synergizes traditional clay handling techniques with digital modeling, providing crucial data for material handling during drying and baking stages. The research presents a significant contribution to the realm of architectural design and computer graphics. It demonstrates the potential of image processing techniques in conjunction with robotic fabrication for creating built environments. The final tiles' appearance, evaluated using the peak signal-to-noise ratio (PSNR), exhibits values between 20 dB and 30 dB, aligning within the realms of acceptable image resemblance according to established image compression standards. [Display omitted] • Implements an integrated design approach for creating relief terracotta panels using robotically fabricated molds. • Utilizes an optimized method combining grayscale image sampling, marching squares algorithm, and genetic algorithms to generate robotic toolpaths. • Offers a diverse range of toolpath options to create varied ridges for relief terracotta panels in terms of amount, disposition, width, and depth. • Employs peak signal-to-noise ratio for validating the resemblance of tangible relief panels to the initial grayscale image. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Theoretical prerequisites for the bionic substantiation of spring soil leveler working bodies parameters
- Author
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L. F. Babitsky, I. V. Sobolevsky, and V. A. Kuklin
- Subjects
leveling devices ,biological prototype ,ridges ,hollows ,power ,traction resistance ,working body ,Agriculture - Abstract
In the system of measures for pre-sowing tillage, special attention should be given to leveling the soil, ensuring an increase in the uniformity of seeding in depth, which has a significant impact on increasing yields. The main solution to this problem is to improve the design of aligners using a mechanical-bionic approach for the analytical description of the optimal forms and parameters of their working bodies. The design of the working body of the spring soil leveler is proposed, the cutting edges of the undercutting wings of which have ridges and hollows in the form of a logarithmic curve with a positive convexity of curvature inside the depressions, developed by the bionic prototype of the mole cricket (Gryllotalpa). Using the methods of agricultural mechanics, the theoretical dependence of the rational depth of the working bodies and the value of the tractive resistance of spring soil leveler on the travel speed, design parameters and physical-mechanical soil properties, which are proved by the results of experimental research on the south carbonated middle loamy black earth have been established. The experimental spring soil leveler provided the reduction of traction resistance by 7...8% (40...49 N) and had the best stability of motion in depth by an average of 1.5 times (± 0.5 cm) in comparison with the serial model of the working bodies of the leveler VPN-5.6 A.
- Published
- 2019
- Full Text
- View/download PDF
33. A Framework for Secure Mobile Cloud Computing
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Ramavathu, Lakshmananaik, Bairam, Manjula, Manchala, Sadanandam, Kacprzyk, Janusz, Series editor, Pal, Nikhil R., Advisory editor, Bello Perez, Rafael, Advisory editor, Corchado, Emilio S., Advisory editor, Hagras, Hani, Advisory editor, Kóczy, László T., Advisory editor, Kreinovich, Vladik, Advisory editor, Lin, Chin-Teng, Advisory editor, Lu, Jie, Advisory editor, Melin, Patricia, Advisory editor, Nedjah, Nadia, Advisory editor, Nguyen, Ngoc Thanh, Advisory editor, Wang, Jun, Advisory editor, Satapathy, Suresh Chandra, editor, Prasad, V. Kamakshi, editor, Rani, B. Padmaja, editor, Udgata, Siba K., editor, and Raju, K. Srujan, editor
- Published
- 2017
- Full Text
- View/download PDF
34. Fingerprint-Based Attendance System Using MATLAB
- Author
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Anushka Swarup, Kottapalli Dheeraj, Adesh Kumar, Kacprzyk, Janusz, Series editor, Pal, Nikhil R., Advisory editor, Bello Perez, Rafael, Advisory editor, Corchado, Emilio S., Advisory editor, Hagras, Hani, Advisory editor, Kóczy, László T., Advisory editor, Kreinovich, Vladik, Advisory editor, Lin, Chin-Teng, Advisory editor, Lu, Jie, Advisory editor, Melin, Patricia, Advisory editor, Nedjah, Nadia, Advisory editor, Nguyen, Ngoc Thanh, Advisory editor, Wang, Jun, Advisory editor, Singh, Rajesh, editor, and Choudhury, Sushabhan, editor
- Published
- 2017
- Full Text
- View/download PDF
35. Response of Sesame (Sesamum indicum L.) to Sowing Methods, Nitrogen and Sulphur Levels.
- Author
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Zeb, Alam and Jan, Amanullah
- Subjects
- *
SULFUR , *SESAME , *SOWING , *SEED yield , *OILSEED plants , *SEED crops - Abstract
Water shortage should be intimidating issue for agriculture crops. Adaptation of modern techniques and management practices in oil seed crops can reduce water shortage risks with optimum yield in oil seed crops. Sesame is being considered the most tolerant crop for avoiding drought conditions with higher yield. Experiments on "response of sesame to sowing methods, nitrogen and sulphur levels" were carried out in Agronomy Research Farms, The University of Agriculture, Peshawar. During two consecutive Kharif growing seasons of 2013 and 2014, respectively. Three sowing methods (flat, ridges and raised bed) were kept as main plot factor, whereas four nitrogen levels (00, 60, 120, and 180 kg ha-1) and four treatments of sulphur (00, 20, 30 and 40 kg ha-1), were kept as sub plot factors, which were replicated four time for each experiment. Urea and ammonium sulphate fertilizers were used as a source of nitrogen and sulfur nutrients. Results showed that all quantitative and qualitative parameters of sesame had significantly influenced by year. Study showed that raised bed sown plots significantly (p = 0.05) produced more: leaves plant-1 (243), leaves area plant-1(444.35cm²), branchesplant-1(9), plant height (198.51cm), and seed yield (1339kg ha-1), were recorded as compared with other sowing methods. It was also resulted from findings that N (180 kg ha-1) had significantly delayed flower and pod formation (7 and 9days) respectively as compared with control plots. Higher: leaves plant-1 (242), leaves area plant-1(492.79cm2), branches plant-1 (9), plant height (212.56cm), and seed yield (1581kg ha-1). Sulphur applied at 40 kg S ha-1 had significantly produced more: leaves area plant-1(446.14cm²), plant height (192.25cm), and seed yield (1346kg ha-1), as compared with lower levels of sulphur. Interactive response of NxS and NxSxSM, were found significant for leaves area plant-1, plant height and seed yield. It is concluded that sowing sesame on raised bed and followed by ridges sowing method, with combined application of 180 kg N ha-1 and 40 kg S ha-1 produced higher yield and yield related components. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
36. Modeling Sand Shoals on the U.S. Atlantic Shelf: Moving Beyond a Site-by-Site Approach.
- Author
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Pickens, Bradley A., Taylor, J. Christopher, Finkbeiner, Mark, Hansen, Deena, and Turner, Lora
- Subjects
- *
BEACH nourishment , *SAND , *BARRIER islands , *CONTINENTAL shelf , *DREDGING spoil , *STANDARD deviations - Abstract
Pickens, B.A.; Taylor, J.C.; Finkbeiner, M.; Hansen, D., and Turner, L., 2021. Modeling sand shoals on the U.S. Atlantic shelf: Moving beyond a site-by-site approach. Journal of Coastal Research, 37(2), 227–237. Coconut Creek (Florida), ISSN 0749-0208. The demand for offshore marine sands has escalated worldwide as sediments are needed for increasingly frequent beach renourishment and barrier island restoration. Sand shoals are often used as a source for dredging material because of the high volume of sand per unit area. Yet, investigations of shoals are typically conducted on a site-by-site basis, and a broader understanding of shoal availability is needed for strategic decision-making, including the mitigation of ocean use conflicts. Here, the primary objective was to model shoal distribution across the U.S. Atlantic shelf, including the Gulf of Mexico. Publicly available bathymetry data were obtained at a relatively coarse 90-m resolution. Variables of depth, standard deviation of depth, slope, bathymetric position index, and distance to shoreline were used as predictors to identify shoals. Unsupervised classifications of the seafloor were conducted to distinguish shoals and swales. Classification accuracy was assessed with validation databases of identified sand resources and named shoals compared to random locations; a visual assessment was also conducted. Shoals were further characterized by their origin. The classifications showed shoals and swales differed from the seafloor. Shoals were more shallow, had higher slope, a higher standard deviation of depth, were closer to the shoreline, and had a more positive bathymetric position index. Shoals were classified on 4.7% of the U.S. Atlantic shelf, and validation showed a percent agreement of 65–93%. Classified shoals visually coincided with the shape and extent of known sand resources. Shoals were characterized as cape-associated, bedform, isolated shelf, or uncharacterized. For the continental shelf, multivariate predictors represented the heterogeneous sloping substrates and the flat, high relief crests of sand shoals. The ability to classify shoals with 90-m resolution bathymetry data in the U.S. Atlantic reveals the methodology may be applicable to identify sand shoals elsewhere in the world with currently available data. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
37. Neues Konzept zum nachhaltigen Süßholzanbau
- Author
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Rinder, Rudolf and Heuberger, Heidi
- Subjects
licorice ,glycyrrhiza ,cultivation ,ridges ,mulching ,content ,Agriculture ,Botany ,QK1-989 - Abstract
Cultivated licorice plants (Glycyrrhiza glabra L., Glycyrrhiza uralensis FISCH) contain smaller amounts of the triterpene saponin Glycyrrhizic Acid (GA) than wild licorice plants. Endangered or overharvested natural habitats (deserts) are already restricted in China and Mongolia. To resolve this problem and select strains with high GA, we propagated high value strains by vigorous underground shoots and developed a sustainable cultivation strategy, called RIPEAD©, for organic licorice production.
- Published
- 2018
- Full Text
- View/download PDF
38. AMPLIFICATION OF SOIL COMPACTION BETWEEN RIDGES AFTER USING PLASTIC MULCH ON ENTIRE SURFACE IN PLASTIC TUNNELS FROM NORTH-EAST OF ROMANIA.
- Author
-
FILIPOV, Feodor and TOPA, Denis
- Subjects
SOIL compaction ,PLASTIC mulching ,BLACK cotton soil ,PARTICLE size determination ,SOIL profiles ,SOIL testing ,PLASTIC films - Abstract
Our studies performed on the plastic tunnels from North-East part of Romania included a field work phase (soil and biological material sampling, soil profiles description, penetration resistance determination, digital images capture), laboratory phase (chemical and physical soil analysis). Based on field and laboratory data were estimated packing density and bulk density restricting rooting. The obtained results have shown that black plastic films on the entire surface of soil favors soil compaction, in the areas located between plants rows (i), the ploughpan conducted to the waterlogging on the bottom part of ploughed layer (ii), root system poorly developed favored some physiological disorders such as Blossom end rot on tomatoes fruits (iii). Soil determination in field (penetration resistance, morphological soil indicators) and laboratory (water distribution, bulk density, size particles distribution) and quality of fruits reveled negative influence of plastic mulch. Strong soil compaction between ridges allows us to recommend avoiding plastic mulch over the entire soil surface. [ABSTRACT FROM AUTHOR]
- Published
- 2020
39. Hybrid minutiae and edge corners feature points for increased fingerprint recognition performance.
- Author
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Nachar, Rabih, Inaty, Elie, Bonnin, Patrick J., and Alayli, Yasser
- Subjects
- *
HUMAN fingerprints , *IMAGE intensifiers , *PATTERN recognition systems , *FEATURE extraction , *EDGES (Geometry) , *MATCHING theory - Abstract
In general, most fingerprint recognition systems are based on the minutiae feature points. When matching two fingerprint images, the goal in most recognition systems is to find the optimal transformation model that aligns their feature points in order to find among them the number of matched or aligned points and then generate a matching score. A major problem in feature extraction stage is that when the fingerprint image is of a poor quality due to skin conditions and sensor noise, that leads to many broken ridges in the image caused by cutline. In this case, the extraction of minutiae leads to a lot of spurious points and the performance of the system will degrade. Usually, image enhancement techniques are applied as preprocessing step to overcome this problem. In this work, we propose to use corner points on fingerprint ridges as new features in addition to the ridges minutiae in order to improve the recognition performance. Every ridge is decomposed into several straight edges (SEs). A straight edge is defined as a straight link of ridge points. On a ridge, the head of the first straight edge and the tail of the last one are two minutia and the intersections of the SEs are the ridge corners. Thus, we propose to use a ridge as primitive rather than individual points for matching. This primitive is a structure consisting of groups of both feature points which are minutiae and corners belonging to the same ridge. Based on this primitive, an intelligent matching technique is introduced using sets of feature points on the same primitive. As a result, the recognition performance is increased since it is based on ridge primitive matching rather than individual minutiae matching. Finally, our experimental results compared with those obtained by other well-known techniques in the literature demonstrate the effectiveness and efficiency of our proposed algorithm. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
40. Ridges
- Author
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Manzello, Samuel L., editor
- Published
- 2020
- Full Text
- View/download PDF
41. A Multibiometric Fingerprint Recognition System Based on the Fusion of Minutiae and Ridges
- Author
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Gudavalli, Madhavi, Kumar, D. Srinivasa, Raju, S. Viswanadha, Kacprzyk, Janusz, Series editor, Satapathy, Suresh Chandra, editor, Govardhan, A., editor, Raju, K. Srujan, editor, and Mandal, J. K., editor
- Published
- 2015
- Full Text
- View/download PDF
42. Granite Weathering in the Velence Hills
- Author
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Mezősi, Gábor, Migon, Piotr, Series editor, and Lóczy, Dénes, editor
- Published
- 2015
- Full Text
- View/download PDF
43. Enhancing productivity of spring maize (Zea mays) through planting methods, varieties and irrigation levels in Punjab
- Author
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Singh, Maninder and Vashist, Krishan Kumar
- Published
- 2016
44. repeated evolution of dental apicobasal ridges in aquatic-feeding mammals and reptiles.
- Author
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McCurry, Matthew R, Evans, Alistair R, Fitzgerald, Erich M G, McHenry, Colin R, Bevitt, Joseph, and Pyenson, Nicholas D
- Subjects
- *
REPTILES , *DENTAL enamel , *MAMMALS , *BIOLOGICAL evolution , *CONVERGENT evolution , *PALEOBIOLOGY - Abstract
Since the Permian, Earth's aquatic ecosystems have been ecologically dominated by numerous lineages of predatory amniotes. Many of these groups evolved elevated ridges of enamel that run down the apical–basal axis of their teeth, referred to here as apicobasal ridges. This trait is commonly used as a taxonomic tool to identify fossil species and higher groupings, but the function of the ridges and their associated ecological significance are poorly understood. Here, we aim to clarify the phylogenetic distribution of apicobasal ridges among amniotes and to examine how the morphology of apicobasal ridges varies across species. We show that these ridges have evolved independently numerous times and are almost exclusively found in aquatic-feeding species. Ridge morphology varies, including tall, pronounced ridges, low, undulating ridges and interweaving ridges. Their internal structure also varies from tooth crowns with locally thickened enamel to undulating enamel–dentine interface. We assess the relative merits of different hypothetical functions of the ridges and propose that although apicobasal ridges might provide some strengthening of the tooth, their morphology and pattern of evolution do not indicate that this is their primary function. Instead, we suggest that apicobasal ridges serve to increase the efficiency of puncture, grip and/or removal. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
45. ETNOARQUEOLOGÍA: RITUALIDAD EN LA SIEMBRA EN CAMELLONES Y CULTURA ANDINA EN EL SUR DEL LAGO SAN PABLO, OTAVALO, ECUADOR.
- Author
-
Sánchez Flores, Francisco Germánico
- Abstract
To demonstrate that rituals were performed on mountain ridges during the Late Integration Period (1250-1525 AD), archaeological excavations were carried out in the La Rinconada sector to the south of Lake San Pablo, Ecuador. In order to better interpret the archaeological data, an ethnographic study was conducted on the cultural practices surrounding agriculture in the Cayambis and Otavalos communities located on the slopes near the ridges; based on ethnohistorical, archaeological and ethnographic research, it is determined that these communities constitute a continuation of the Caranqui culture, although given that there were social, political and religious transformations caused by the Inca and Spanish conquests. From comparison of the archaeological data with the ethnographic data, it was determined that rituals that were carried out in the fields along the ridges were linked to the sowing of seeds. [ABSTRACT FROM AUTHOR]
- Published
- 2019
46. Effects of ridge height and spacing on the near-surface airflow field and on wind erosion of a sandy soil: Results of a wind tunnel study.
- Author
-
Jia, Wenru, Zhang, Chunlai, Zou, Xueyong, Cheng, Hong, Kang, Liqiang, Liu, Bo, Li, Jifeng, Shen, Yaping, Liu, Wei, Fang, Yi, and Li, Huiru
- Subjects
- *
SANDY soils , *AIR flow , *WIND tunnels , *VELOCITY , *FRICTION , *SEDIMENTS - Abstract
Highlights • We measured the airflow field near the ground that contained non-erodible ridges. • Ridges of small spacing act as roughness elements but as barriers with large spacing. • Wind erosion is not uniform either on the whole bed or between the ridges. • We developed a model for predicting sand transport over sand beds with ridges. Abstract In wind tunnel experiments, we measured the airflow field near the ground surface and the resulting sand transport rate over a sand bed that contained widely but uniformly spaced non-erodible ridges. We found that when airflow passed over the bed, the wind velocity changed drastically around the first ridge, but the magnitude of the change decreased gradually moving downwind until a relatively stable airflow developed, characterized by regular fluctuation over the uniformly spaced ridges. The distance from the first ridge to the zone of stable airflow increased with increasing ridge height or spacing between ridges. This airflow field led to a non-uniform distribution of wind erosion that affected total sediment transport from the sand bed. Using our wind tunnel simulation results as inputs for existing sediment transport equations, we developed a model to predict sediment transport (q) over a sand bed that contained widely spaced ridges: q = C ' d D ρ g u * 2 u * - u * t e x p (- a H u * 3 n). The model accounts for the ridge height (H), number of ridges per unit length (n), and the wind's free-stream friction velocity (u *) and threshold friction velocity (u *t). We discussed the different mechanisms by which ridges influence the near-surface airflow at large spacing (> 5 H) and small spacing (≤ 5 H). The ridges appear to affect the airflow as roughness elements when the spacing is small, but act as barriers to the wind when the spacing is large. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
47. Two robust approaches to multicomponent signal reconstruction from STFT ridges.
- Author
-
Zhu, Xiangxiang, Zhang, Zhuosheng, Gao, Jinghuai, and Li, Wenting
- Subjects
- *
SIGNAL reconstruction , *FOURIER transforms , *ROBUST control , *OUTLIERS (Statistics) , *WAVELET transforms - Abstract
The problem of how to accurately reconstruct the multicomponent signal from the ridges of the short-time Fourier transform (STFT) is considered. Especially when time-frequency representations contain strong noise corruption and crossed components, exact reconstruction becomes more difficult. In this paper, we propose two robust ridge reconstruction approaches, i.e., weighted ridge reconstruction (WRR) and self-paced ridge reconstruction (SPRR). The former is aim to select a more robust loss function to eliminate the influence of the strong noise and outliers. A half-quadratic optimization algorithm is developed to solve the proposed problem efficiently. The latter incorporates self-paced learning (SPL) method into ridge reconstruction model to sequentially include ridge points into signal reconstruction from easy to complex, which not only can suppress noise and outliers, but also can avoid a bad result in the presence of missing observations. Simulation and real-life signals are employed to show the effectiveness and practicability of the proposed approaches. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
48. Slope morphologies offshore Dakhla (SW Moroccan margin)
- Author
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Benabdellouahed Massinissa, Baltzer Agnes, Rabineau Marina, Aslanian Daniel, Sahabi Mohamed, Germond Fabien, Loubrieu Benoit, and Biari Youssef
- Subjects
African margin ,Bathymetry ,Seismic interpretation ,Pockmarks ,Ridges ,Scarps ,Geology ,QE1-996.5 - Abstract
This study explores a portion of the West African margin at the junction between two well-known segments offshore Dakhla and offshore Mauritania with destructional architecture characterized by giant slides. In between these two segments, the Dakhla segment has historically been described as a constructional section. During an oceanographic Dakhla cruise (2002), high resolution seismic data, swath bathymetry and imagery were acquired around latitude 23°N, offshore Dakhla. This new data set reveals the existence of varied and complex morphologies on the continental slope, interpreted as a “shallot-shaped” canyon, seafloor depressions or pockmarks, ridges and scarps. These morphologies are interpreted as clues of sedimentary transfers and rupture processes. A scenario is proposed for the development of these different sedimentary morphologies.
- Published
- 2016
- Full Text
- View/download PDF
49. Analogs of Ridge Skin and Papillary Patterns in the Nature and the Significance of Their Study for Forensic Science and Forensic Examination
- Author
-
Shamil Khaziev
- Subjects
forensics ,papillary pattern ,Social pathology. Social and public welfare. Criminology ,striped pattern, tiger skin ,ridges ,identification ,food and beverages ,dermatoglyphics ,fingerprints ,forensic examination ,HV1-9960 ,ridged skin - Abstract
Patterns similar to the papillary patterns of human fingers, palms, and soles can be found in living and inanimate nature. Studying such patterns and the structure of the ridged skin of humans and primates in comparison with similar formations on other objects is necessary for forensic science, forensic traceology, fingerprinting, and biometric identification. The article analyzes the history of the study of the ridged skin of humans, primates, and other animals by forensic scientists, zoologists, anthropologists, and representatives of other sciences.The author proposes systemizing and classifying the information about the analogs of papillary patterns and ridged skin on such grounds as the genus and type of carrier objects, relief structure, degree of comparability with the papillary pattern of human hands and soles.The article presents the most indicative varieties of analogs of papillary patterns in mammals, birds, fish, insects, corals, plants, and fungi. The author has studied and systemized structural features of the striped pattern of the skin of tigers and zebras, crests and stripes in corals, stripes and ridged patterns in fish. The data obtained on ridge formations, which are similar in structure and shape to the papillary patterns of human fingers and palms, will help to avoid expert errors during fingerprinting examination or erroneous placement of images of such formations in forensic databases.Knowledge of the structural features and properties of striped patterns of skins of specially protected wild animals, as well as the crest surface of paleontological museum objects, should be used for their identification by photo and video images in cases of embezzlement, smuggling, illegal hunting, and illegal trafficking.
- Published
- 2022
50. Sea-Ice Observation: Advances and Challenges
- Author
-
Melling, Humfrey, Lemke, Peter, editor, and Jacobi, Hans-Werner, editor
- Published
- 2012
- Full Text
- View/download PDF
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