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Journal articles on the topic 'Double descent'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Stevenson, Robert A., Dennis Evangelista, and Cindy V. Looy. "When conifers took flight: a biomechanical evaluation of an imperfect evolutionary takeoff." Paleobiology 41, no. 2 (March 2015): 205–25. http://dx.doi.org/10.1017/pab.2014.18.

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AbstractManifera talaris, a voltzian conifer from the late early to middle Permian (ca. 270 Ma) of Texas, is the earliest known conifer to produce winged seeds indicative of autorotating flight. In contrast to autorotating seeds and fruits of extant plants, the ones ofM. talarisare exceptional in that they have variable morphology. They bore two wings that produced a range of wing configurations, from seeds with two equal-sized wings to single-winged specimens, via various stages of underdevelopment of one of the wings. To examine the effects of various seed morphologies on aerodynamics and dispersal potential, we studied the flight performance of paper models of three morphotypes: symmetric double-winged, asymmetric double-winged, and single-winged. Using a high-speed camera we identified the mode of descent (plummeting, gliding, autorotation) and quantified descent speed, autorotation frequency, and other flight characteristics. To validate such modeling as an inferential tool, we compared descent of extant analogues (kauri;Agathis australis) with descent of similarly constructed seed models. All three seed morphotypes exhibited autorotating flight behavior. However, double-winged seeds, especially symmetric ones, failed to initiate slow autorotative descent more frequently than single-winged seeds. Even when autorotating, symmetric double-winged seeds descend faster than asymmetric double-winged ones, and descent is roughly twice as fast compared to single-winged seeds. Moreover, the relative advantage that (effectively) single-winged seeds have in slowing descent during autorotation becomes larger as seed weight increases. Hence, the range in seed wing configurations inM. talarisproduced a wide variation in potential dispersal capacity. Overall, our results indicate that the evolutionarily novel autorotating winged seeds must have improved conifer seed dispersal, in a time when animal vectors for dispersion were virtually absent. Because of the range in wing configuration, the early evolution of autorotative flight in conifers was a functionally imperfect one, which provides us insight into the evolutionary developmental biology of autorotative seeds in conifers.

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2

Loog, Marco, Tom Viering, Alexander Mey, Jesse H. Krijthe, and David M. J. Tax. "A brief prehistory of double descent." Proceedings of the National Academy of Sciences 117, no. 20 (May 5, 2020): 10625–26. http://dx.doi.org/10.1073/pnas.2001875117.

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3

Nakkiran, Preetum, Gal Kaplun, Yamini Bansal, Tristan Yang, Boaz Barak, and Ilya Sutskever. "Deep double descent: where bigger models and more data hurt*." Journal of Statistical Mechanics: Theory and Experiment 2021, no. 12 (December 1, 2021): 124003. http://dx.doi.org/10.1088/1742-5468/ac3a74.

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Abstract We show that a variety of modern deep learning tasks exhibit a ‘double-descent’ phenomenon where, as we increase model size, performance first gets worse and then gets better. Moreover, we show that double descent occurs not just as a function of model size, but also as a function of the number of training epochs. We unify the above phenomena by defining a new complexity measure we call the effective model complexity and conjecture a generalized double descent with respect to this measure. Furthermore, our notion of model complexity allows us to identify certain regimes where increasing (even quadrupling) the number of train samples actually hurts test performance.

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4

Kräuchi, Andreas, Rolf Philipona, Gonzague Romanens, Dale F. Hurst, Emrys G. Hall, and Allen F. Jordan. "Controlled weather balloon ascents and descents for atmospheric research and climate monitoring." Atmospheric Measurement Techniques 9, no. 3 (March 7, 2016): 929–38. http://dx.doi.org/10.5194/amt-9-929-2016.

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Abstract. In situ upper-air measurements are often made with instruments attached to weather balloons launched at the surface and lifted into the stratosphere. Present-day balloon-borne sensors allow near-continuous measurements from the Earth's surface to about 35 km (3–5 hPa), where the balloons burst and their instrument payloads descend with parachutes. It has been demonstrated that ascending weather balloons can perturb the air measured by very sensitive humidity and temperature sensors trailing behind them, particularly in the upper troposphere and lower stratosphere (UTLS). The use of controlled balloon descent for such measurements has therefore been investigated and is described here. We distinguish between the single balloon technique that uses a simple automatic valve system to release helium from the balloon at a preset ambient pressure, and the double balloon technique that uses a carrier balloon to lift the payload and a parachute balloon to control the descent of instruments after the carrier balloon is released at preset altitude. The automatic valve technique has been used for several decades for water vapor soundings with frost point hygrometers, whereas the double balloon technique has recently been re-established and deployed to measure radiation and temperature profiles through the atmosphere. Double balloon soundings also strongly reduce pendulum motion of the payload, stabilizing radiation instruments during ascent. We present the flight characteristics of these two ballooning techniques and compare the quality of temperature and humidity measurements made during ascent and descent.

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5

Kräuchi, A., R. Philipona, G. Romanens, D. F. Hurst, E. G. Hall, and A. F. Jordan. "Controlled weather balloon ascents and descents for atmospheric research and climate monitoring." Atmospheric Measurement Techniques Discussions 8, no. 12 (December 3, 2015): 12559–88. http://dx.doi.org/10.5194/amtd-8-12559-2015.

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Abstract. In situ upper-air measurements are often made with instruments attached to weather balloons launched at the surface and lifted into the stratosphere. Present day balloon-borne sensors allow near-continuous measurements from the Earth's surface to about 35 km (3–5 hPa), where the balloons burst and their instrument payloads descend with parachutes. It has been demonstrated that ascending weather balloons can perturb the air measured by very sensitive humidity and temperature sensors trailing behind them, particularly in the upper troposphere and lower stratosphere (UTLS). The use of controlled balloon descent for such measurements has therefore been investigated and is described here. We distinguish between the one balloon technique that uses a simple automatic valve system to release helium from the balloon at a pre-set ambient pressure, and the double balloon technique that uses a carrier balloon to lift the payload and a parachute balloon to control the descent of instruments after the carrier balloon is released at pre-set altitude. The automatic valve technique has been used for several decades for water vapor soundings with frost point hygrometers, whereas the double balloon technique has recently been re-established and deployed to measure radiation and temperature profiles through the atmosphere. Double balloon soundings also strongly reduce pendulum motion of the payload, stabilizing radiation instruments during ascent. We present the flight characteristics of these two ballooning techniques and compare the quality of temperature and humidity measurements made during ascent and descent.

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6

Belkin, Mikhail, Daniel Hsu, and Ji Xu. "Two Models of Double Descent for Weak Features." SIAM Journal on Mathematics of Data Science 2, no. 4 (January 2020): 1167–80. http://dx.doi.org/10.1137/20m1336072.

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7

Groechenig, Michael. "Adelic descent theory." Compositio Mathematica 153, no. 8 (May 31, 2017): 1706–46. http://dx.doi.org/10.1112/s0010437x17007217.

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A result of André Weil allows one to describe rank $n$ vector bundles on a smooth complete algebraic curve up to isomorphism via a double quotient of the set $\text{GL}_{n}(\mathbb{A})$ of regular matrices over the ring of adèles (over algebraically closed fields, this result is also known to extend to $G$-torsors for a reductive algebraic group $G$). In the present paper we develop analogous adelic descriptions for vector and principal bundles on arbitrary Noetherian schemes, by proving an adelic descent theorem for perfect complexes. We show that for Beilinson’s co-simplicial ring of adèles $\mathbb{A}_{X}^{\bullet }$, we have an equivalence $\mathsf{Perf}(X)\simeq |\mathsf{Perf}(\mathbb{A}_{X}^{\bullet })|$ between perfect complexes on $X$ and cartesian perfect complexes for $\mathbb{A}_{X}^{\bullet }$. Using the Tannakian formalism for symmetric monoidal $\infty$-categories, we conclude that a Noetherian scheme can be reconstructed from the co-simplicial ring of adèles. We view this statement as a scheme-theoretic analogue of Gelfand–Naimark’s reconstruction theorem for locally compact topological spaces from their ring of continuous functions. Several results for categories of perfect complexes over (a strong form of) flasque sheaves of algebras are established, which might be of independent interest.

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8

Stanimirović, Predrag S., Gradimir V. Milovanović, Milena J. Petrović, and Nataša Z. Kontrec. "A Transformation of Accelerated Double Step Size Method for Unconstrained Optimization." Mathematical Problems in Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/283679.

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A reduction of the originally double step size iteration into the single step length scheme is derived under the proposed condition that relates two step lengths in the accelerated double step size gradient descent scheme. The proposed transformation is numerically tested. Obtained results confirm the substantial progress in comparison with the single step size accelerated gradient descent method defined in a classical way regarding all analyzed characteristics: number of iterations, CPU time, and number of function evaluations. Linear convergence of derived method has been proved.

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9

Stanimirović, Predrag S., Bilall I. Shaini, Jamilu Sabi’u, Abdullah Shah, Milena J. Petrović, Branislav Ivanov, Xinwei Cao, Alena Stupina, and Shuai Li. "Improved Gradient Descent Iterations for Solving Systems of Nonlinear Equations." Algorithms 16, no. 2 (January 18, 2023): 64. http://dx.doi.org/10.3390/a16020064.

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This research proposes and investigates some improvements in gradient descent iterations that can be applied for solving system of nonlinear equations (SNE). In the available literature, such methods are termed improved gradient descent methods. We use verified advantages of various accelerated double direction and double step size gradient methods in solving single scalar equations. Our strategy is to control the speed of the convergence of gradient methods through the step size value defined using more parameters. As a result, efficient minimization schemes for solving SNE are introduced. Linear global convergence of the proposed iterative method is confirmed by theoretical analysis under standard assumptions. Numerical experiments confirm the significant computational efficiency of proposed methods compared to traditional gradient descent methods for solving SNE.

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10

Dieci, Luca, Manuela Manetta, and Haomin Zhou. "Double descent and intermittent color diffusion for landscape exploration." Numerical Algorithms 85, no. 1 (November 6, 2019): 145–69. http://dx.doi.org/10.1007/s11075-019-00807-6.

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11

Dar, Yehuda, and Richard G. Baraniuk. "Double Double Descent: On Generalization Errors in Transfer Learning between Linear Regression Tasks." SIAM Journal on Mathematics of Data Science 4, no. 4 (December 20, 2022): 1447–72. http://dx.doi.org/10.1137/22m1469559.

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12

Xanthouli, Panagiota. "Dermatomyositis: Double trouble – Case Report." Kompass Autoimmun 3, no. 1 (2021): 19–20. http://dx.doi.org/10.1159/000514046.

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<b>Background:</b> Each myositis-specific autoantibody (MSA) tends to have a distinct clinical presentation. Coexistence of MSAs do not commonly occur. If they do, it is unknown if there is an overlap of clinical features or prognostic implications. There are a few reported cases of overlap between these antibodies, mostly reported in patients with Japanese descent. Our aim for this case report is to turn more attention and interest for future MSA profile studies in the Hispanic population, which may hopefully spur better therapies if we realize the prognostic implications of certain myositis subsets including double-positive autoantibody syndromes. <b>Case presentation:</b> A 27-year-old Hispanic female was admitted to the medical intensive care unit due to acute hypoxemic respiratory failure secondary to acute respiratory distress syndrome (ARDS). She had failed conventional mechanical ventilation and was cannulated for venovenous extracorporeal membrane oxygenation (VV-ECMO) to manage her respiratory failure. She had erythematous scaly plaques on bilateral 3rd metacarpophalangeal joints on examination. Her autoimmune workup revealed positivity for both anti-PL-7(threonyl) and anti-melanoma differentiation-associated gene 5 (MDA5) autoantibodies. After extensive evaluation, it was concluded that she had rapidly progressive interstitial lung disease (RPILD) due to amyopathic dermatomyositis. Despite maximal medical management, she was ultimately transitioned to comfort care measures and expired. <b>Conclusion:</b> We would like to highlight the rarity of double antibody positive amyopathic dermatomyositis. This unique clinical presentation has only been reported in persons of Japanese descent. Our case is likely to be the first reported to occur in a person of Hispanic descent in the United States. The rarity of our case could stimulate further study of overlapping MSA to understand its varied presentations and prognoses including possible tendency toward a rapidly progressive ILD phenotype. Earlier detection of these clinical syndromes can lead to better outcomes for patients with RPILD. This case report could also herald an increased recognition and understanding of MSA profile in the Hispanic population in the USA.

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13

Xanthouli, Panagiota. "Dermatomyositis: Double trouble – Case Report." Kompass Pneumologie 9, no. 3 (2021): 130–31. http://dx.doi.org/10.1159/000515143.

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<b>Background:</b> Each myositis-specific autoantibody (MSA) tends to have a distinct clinical presentation. Coexistence of MSAs do not commonly occur. If they do, it is unknown if there is an overlap of clinical features or prognostic implications. There are a few reported cases of overlap between these antibodies, mostly reported in patients with Japanese descent. Our aim for this case report is to turn more attention and interest for future MSA profile studies in the Hispanic population, which may hopefully spur better therapies if we realize the prognostic implications of certain myositis subsets including double-positive autoantibody syndromes. <b>Case presentation:</b> A 27-year-old Hispanic female was admitted to the medical intensive care unit due to acute hypoxemic respiratory failure secondary to acute respiratory distress syndrome (ARDS). She had failed conventional mechanical ventilation and was cannulated for venovenous extracorporeal membrane oxygenation (VV-ECMO) to manage her respiratory failure. She had erythematous scaly plaques on bilateral 3rd metacarpophalangeal joints on examination. Her autoimmune workup revealed positivity for both anti-PL-7(threonyl) and anti-melanoma differentiation-associated gene 5 (MDA5) autoantibodies. After extensive evaluation, it was concluded that she had rapidly progressive interstitial lung disease (RPILD) due to amyopathic dermatomyositis. Despite maximal medical management, she was ultimately transitioned to comfort care measures and expired. <b>Conclusion:</b> We would like to highlight the rarity of double antibody positive amyopathic dermatomyositis. This unique clinical presentation has only been reported in persons of Japanese descent. Our case is likely to be the first reported to occur in a person of Hispanic descent in the United States. The rarity of our case could stimulate further study of overlapping MSA to understand its varied presentations and prognoses including possible tendency toward a rapidly progressive ILD phenotype. Earlier detection of these clinical syndromes can lead to better outcomes for patients with RPILD. This case report could also herald an increased recognition and understanding of MSA profile in the Hispanic population in the USA.

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14

Li, Xiangli, Wen Zhang, Xiaoliang Dong, and Juanjuan Shi. "An Inexact Update Method with Double Parameters for Nonnegative Matrix Factorization." Mathematical Problems in Engineering 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/2173914.

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Nonnegative matrix factorization (NMF) has been used as a powerful date representation tool in real world, because the nonnegativity of matrices is usually required. In recent years, many new methods are available to solve NMF in addition to multiplicative update algorithm, such as gradient descent algorithms, the active set method, and alternating nonnegative least squares (ANLS). In this paper, we propose an inexact update method, with two parameters, which can ensure that the objective function is always descent before the optimal solution is found. Experiment results show that the proposed method is effective.

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15

Wang, W. B., R. F. Hu, S. J. Xu, and Z. N. Wu. "Influence of aspect ratio on tumbling plates." Journal of Fluid Mechanics 733 (September 26, 2013): 650–79. http://dx.doi.org/10.1017/jfm.2013.461.

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AbstractThe tumbling motion of freely falling plates with aspect ratio ranging from 2 to 10 is studied using both experimental measurement and simplified lifting line theory. The trajectories of plates are recorded by high-speed video camera and analysed to obtain instantaneous and average kinematic and aerodynamic parameters, including the descent angle, rotating speed, descent velocities, lift and drag coefficients, and their fluctuation spectrums. A double period rotation with period doubling is observed here for some range of aspect ratio and the double frequency is determined from a Fourier analysis. By adding a correction from the inducing effect of trailing vortices and wing-tip vortices to the corresponding two-dimensional force and torque expressions, a simplified kinematic model is obtained which successfully predicts the qualitative influence of aspect ratio on the averaged kinematics, that the descent angle and the vertical descent velocity component are decreasing functions of the aspect ratio, while the rotation speed and horizontal velocity component are increasing functions of the aspect ratio. For decreasing aspect ratio, the induced drag due to the trailing and tip vortices reduces the lift to drag ratio and thus increases the descent angle, while the dissipative torque due to translational induced drag decreases the rotation speed.

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16

Beasley, Spencer W., and Alex W. Auldist. "CROSSED TESTICULAR ECTOPIA IN ASSOCIATION WITH DOUBLE INCOMPLETE TESTICULAR DESCENT." ANZ Journal of Surgery 55, no. 3 (June 1985): 301–3. http://dx.doi.org/10.1111/j.1445-2197.1985.tb00090.x.

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17

Onose, Alexandru, and Bogdan Dumitrescu. "Adaptive matching pursuit using coordinate descent and double residual minimization." Signal Processing 93, no. 11 (November 2013): 3143–50. http://dx.doi.org/10.1016/j.sigpro.2013.05.001.

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18

GOVINDARAJAN, SURESH, T. JAYARAMAN, VARGHESE JOHN, and PARTHASARATHI MAJUMDAR. "STATES OF NONZERO GHOST NUMBER IN c<1 MATTER COUPLED TO 2D GRAVITY." Modern Physics Letters A 07, no. 12 (April 20, 1992): 1063–77. http://dx.doi.org/10.1142/s021773239200094x.

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We study c<1 matter coupled to gravity in the Coulomb gas formalism using the double cohomology of the string BRST and Felder BRST charges. We find that states outside the primary conformal grid are related to the states of nonzero ghost number by means of descent equations given by the double cohomology. Some aspects of the Virasoro structure of the Liouville-Fock space are studied. As a consequence, states of nonzero ghost number are easily constructed by “solving” these descent equations. This enables us to map ghost number conserving correlation functions involving nonzero ghost number states into those involving states outside the primary conformal grid.

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19

Lu, Zhenglong, Jie Li, Xi Zhang, Kaiqiang Feng, Xiaokai Wei, Debiao Zhang, Jing Mi, and Yang Liu. "A New In-Flight Alignment Method with an Application to the Low-Cost SINS/GPS Integrated Navigation System." Sensors 20, no. 2 (January 16, 2020): 512. http://dx.doi.org/10.3390/s20020512.

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The optimization-based alignment (OBA) methods, which are implemented by the optimal attitude estimation using vector observations—also called double-vectors—have proven to be effective at solving the in-flight alignment (IFA) problem. However, the traditional OBA methods are not applicable for the low-cost strap-down inertial navigation system (SINS) since the error of double-vectors will be accumulated over time due to the substantial drift of micro-electronic- mechanical system (MEMS) gyroscope. Moreover, the existing optimal estimation method is subject to a large computation burden, which results in a low alignment speed. To address these issues, in this article we propose a new fast IFA method based on modified double-vectors construction and the gradient descent method. To be specific, the modified construction method is implemented by reducing the integration interval and identifying the gyroscope bias during the construction procedure, which improves the accuracy of double-vectors and IFA; the gradient descent scheme is adopted to estimate the optimal attitude of alignment without complex matrix operation, which results in the improvement of alignment speed. The effect of different sizes of mini-batch on the performance of the gradient descent method is also discussed. Extensive simulations and vehicle experiments demonstrate that the proposed method has better accuracy and faster alignment speed than the related traditional methods for the low-cost SINS/global positioning system (GPS) integrated navigation system

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20

Fadnavis, S., and G. Beig. "Spatiotemporal variation of the ozone QBO in MLS data by wavelet analysis." Annales Geophysicae 26, no. 12 (November 25, 2008): 3719–30. http://dx.doi.org/10.5194/angeo-26-3719-2008.

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Abstract. Spatiotemporal characteristics of the ozone quasi-biennial oscillation (QBO) over the tropical-subtropical stratosphere (40° S–40° N) have been examined by analyzing data from the Microwave Limb Sounder (MLS) aboard Upper Atmospheric Research Satellite (UARS) for the period 1992–1999. A combination of regression analysis and wavelet analysis combines to act as an accurate QBO filter. Wavelet analysis provides inter-annual variability of amplitude and phase of the ozone QBO in the vertical structure of tropical-subtropical stratosphere. It gives minute details of phase propagation and descend rates, which can be used as input to models. Latitude-height structure shows evidence of a secondary meridional circulation induced by the QBO as double peak structure at the equator with maximum amplitude at two pressure levels 30 hPa and 9 hPa and a node at 14 hPa. The equatorial maxima are out of phase with each other. The maximum amplitude (~1.4 ppmv) of the ozone QBO was observed near the equator at 10 hPa. Descent rate of the easterly phase is greater than westerly. The lag correlation of the ozone QBO with circulation and variation of descent rates in the vertical structure of the stratosphere are examined in detail. In the equatorial upper stratosphere ozone anomalies descent with the rate ~1.5 km/month but in tropics and subtropics (above 2 hPa) they propagate upward.

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21

Ribeiro, Antônio H., Johannes N. Hendriks, Adrian G. Wills, and Thomas B. Schön. "Beyond Occam’s Razor in System Identification: Double-Descent when Modeling Dynamics." IFAC-PapersOnLine 54, no. 7 (2021): 97–102. http://dx.doi.org/10.1016/j.ifacol.2021.08.341.

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22

Scelza, Brooke A., Sean P. Prall, and Nancy E. Levine. "The disequilibrium of double descent: changing inheritance norms among Himba pastoralists." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1780 (July 15, 2019): 20180072. http://dx.doi.org/10.1098/rstb.2018.0072.

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Matrilineal systems in sub-Saharan Africa tend to co-occur with horticulture and are rare among pastoralists, with the causal arrow pointing from the introduction of cattle to the loss of matriliny. However, most work on this topic stems from either phylogenetic analyses or historical data. To better understand the shift from matrilineal to patrilineal inheritance that occurred among Bantu populations after the adoption of pastoralism, data from societies that are currently in transition are needed. Himba pastoralists, who practice ‘double descent’, may represent one such society. Using multi-generational ethnography and structured survey data, we describe current norms and preferences about inheritance, as well as associated norms related to female autonomy. We find that preferences for patrilineal inheritance are strong, despite the current practice of matrilineal cattle inheritance. We also find that a preference for patriliny predicts greater acceptance of norm violating behaviour favouring sons over nephews. Finally, we show that there are important generational differences in how men view women's autonomy, which are probably attributable to both changing norms about inheritance and exposure to majority-culture views on women's roles. Our data shed light on how systemic change like the shifts in descent reckoning that occurred during the Bantu expansion can occur. This article is part of the theme issue ‘The evolution of female-biased kinship in humans and other mammals’.

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23

Dijk, Toos, and Nico Jonge. "The house on the hill; Moieties and double descent in Babar." Bijdragen tot de taal-, land- en volkenkunde / Journal of the Humanities and Social Sciences of Southeast Asia 143, no. 1 (1987): 54–104. http://dx.doi.org/10.1163/22134379-90003341.

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24

Rebbeck, Timothy R., Susan S. Devesa, Bao-Li Chang, Clareann H. Bunker, Iona Cheng, Kathleen Cooney, Rosalind Eeles, et al. "Global Patterns of Prostate Cancer Incidence, Aggressiveness, and Mortality in Men of African Descent." Prostate Cancer 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/560857.

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Prostate cancer (CaP) is the leading cancer among men of African descent in the USA, Caribbean, and Sub-Saharan Africa (SSA). The estimated number of CaP deaths in SSA during 2008 was more than five times that among African Americans and is expected to double in Africa by 2030. We summarize publicly available CaP data and collected data from the men of African descent and Carcinoma of the Prostate (MADCaP) Consortium and the African Caribbean Cancer Consortium (AC3) to evaluate CaP incidence and mortality in men of African descent worldwide. CaP incidence and mortality are highest in men of African descent in the USA and the Caribbean. Tumor stage and grade were highest in SSA. We report a higher proportion of T1 stage prostate tumors in countries with greater percent gross domestic product spent on health care and physicians per 100,000 persons. We also observed that regions with a higher proportion of advanced tumors reported lower mortality rates. This finding suggests that CaP is underdiagnosed and/or underreported in SSA men. Nonetheless, CaP incidence and mortality represent a significant public health problem in men of African descent around the world.

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25

Sugishima, Takashi. "Double descent, alliance, and botanical metaphors among the Lionese of Central Flores." Bijdragen tot de taal-, land- en volkenkunde / Journal of the Humanities and Social Sciences of Southeast Asia 150, no. 1 (1994): 146–70. http://dx.doi.org/10.1163/22134379-90003097.

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26

Zhang, Naimin. "A Study on the Optimal Double Parameters for Steepest Descent with Momentum." Neural Computation 27, no. 4 (April 2015): 982–1004. http://dx.doi.org/10.1162/neco_a_00710.

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This letter presents the stability analysis for two steepest descent algorithms with momentum for quadratic functions. The corresponding local optimal parameters in Torii and Hagan ( 2002 ) and Zhang ( 2013 ) are extended to the global optimal parameters, that is, both the optimal learning rates and the optimal momentum factors are obtained simultaneously which make for the fastest convergence.

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27

Njororai Simiyu, Wycliffe W. "Players of African descent representing European national football teams: a double-edged sword." Soccer & Society 22, no. 4 (March 30, 2021): 411–28. http://dx.doi.org/10.1080/14660970.2021.1906539.

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28

Liu, Chein-Shan. "A double optimal descent algorithm for iteratively solving ill-posed linear inverse problems." Inverse Problems in Science and Engineering 23, no. 1 (February 17, 2014): 38–66. http://dx.doi.org/10.1080/17415977.2014.880905.

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29

Beck, Amir. "The 2-Coordinate Descent Method for Solving Double-Sided Simplex Constrained Minimization Problems." Journal of Optimization Theory and Applications 162, no. 3 (December 3, 2013): 892–919. http://dx.doi.org/10.1007/s10957-013-0491-5.

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30

Gausset, Quentin. "Double Unilineal Descent and Triple Kinship Terminology: The Case of the Kwanja of Cameroon." Journal of the Royal Anthropological Institute 4, no. 2 (June 1998): 309. http://dx.doi.org/10.2307/3034504.

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31

Chang, Xiangyu, Yingcong Li, Samet Oymak, and Christos Thrampoulidis. "Provable Benefits of Overparameterization in Model Compression: From Double Descent to Pruning Neural Networks." Proceedings of the AAAI Conference on Artificial Intelligence 35, no. 8 (May 18, 2021): 6974–83. http://dx.doi.org/10.1609/aaai.v35i8.16859.

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Deep networks are typically trained with many more parameters than the size of the training dataset. Recent empirical evidence indicates that the practice of overparameterization not only benefits training large models, but also assists – perhaps counterintuitively – building lightweight models. Specifically, it suggests that overparameterization benefits model pruning / sparsification. This paper sheds light on these empirical findings by theoretically characterizing the high-dimensional asymptotics of model pruning in the overparameterized regime. The theory presented addresses the following core question: ``should one train a small model from the beginning, or first train a large model and then prune?''. We analytically identify regimes in which, even if the location of the most informative features is known, we are better off fitting a large model and then pruning rather than simply training with the known informative features. This leads to a new double descent in the training of sparse models: growing the original model, while preserving the target sparsity, improves the test accuracy as one moves beyond the overparameterization threshold. Our analysis further reveals the benefit of retraining by relating it to feature correlations. We find that the above phenomena are already present in linear and random-features models. Our technical approach advances the toolset of high-dimensional analysis and precisely characterizes the asymptotic distribution of over-parameterized least-squares. The intuition gained by analytically studying simpler models is numerically verified on neural networks.

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32

Zhang, Junyi, Zhuopeng Zhang, Haifeng Li, and Xu Liu. "Optimizing double-phase method based on gradient descent algorithm with complex spectrum loss function." Optics Communications 514 (July 2022): 128136. http://dx.doi.org/10.1016/j.optcom.2022.128136.

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Hu, Changbin, Linshu Cheng, Shanna Luo, and Heming Yan. "Robust control-based power quality optimization strategy for inverters." Journal of Physics: Conference Series 2215, no. 1 (February 1, 2022): 012002. http://dx.doi.org/10.1088/1742-6596/2215/1/012002.

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Abstract A dynamic compensation control strategy based on a residual observer combined with a gradient descent optimization algorithm is proposed to address the power quality problem of distributed AC networks. The robust control structure based on the residual observer is designed according to the theory of Plug and Play control framework. The proposed structure is effective in improving the dynamic performance of the system without changing the structure and parameters. A gradient descent optimization algorithm is used to optimize the parameters of the rectified control structure online. Based on the need for fast response capability and stable performance of distributed grid systems, the gradient descent algorithm is optimized using the model matching principle, which provides a theoretical basis for the selection of initial points in the optimization algorithm. A low-order derivation form of the robust control structure is given through a step-down process to further enhance the speed of optimization under this strategy. The analysis shows that the strategy effectively enhances the robustness of the distributed grid system in comparison with the conventional double closed-loop control. Modelling simulation results verify the effectiveness of the proposed control strategy.

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Ruano, Rosario Martín, and Carmen África Vidal Claramonte. "Asymmetries in/of Translation: Translating Translated Hispanicism(s)1." TTR : traduction, terminologie, rédaction 17, no. 1 (December 22, 2005): 81–105. http://dx.doi.org/10.7202/011974ar.

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Abstract This paper focuses on the hybrid writing of American authors of Hispanic descent in its double dimension as a process of translation and representation, and also as a process subject to other processes of translation and representation, including scholarly assessment and description. It examines the problems and ideological implications of translating these translated fictions, inasmuch as this writing calls into question both traditional visions of literature and hegemonic translation models.

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Ashton, John. "The Johannine Son of Man: A New Proposal." New Testament Studies 57, no. 4 (September 5, 2011): 508–29. http://dx.doi.org/10.1017/s0028688511000178.

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How is the association of the descent/ascent motif with the Johannine Son of Man to be explained if the gnosticism theory no longer holds? ἀναβέβηκεν (3.13) is usually taken to refer to Jesus' final ascension. But Odeberg saw that it refers to a tradition of heavenly ascent in Jesus' lifetime. Bühner argued rather for a double reference—to the ascent of a visionary seer involving a metamorphosis into a heavenly beinganda final ascent at death. Yet he ignores the likelihood, sustained by Jarl Fossum and Morton Smith, that the transfiguration tradition was based on an authentic memory. In chs. 9 and 5 the evangelist recognizes that Jesus had been invested with the authority of the heavenly Son of Man. He sees the crucifixion as an exaltation (3.14), and follows a statement of Jesus' ascent, descent and exaltation by a full summary of God's loving gift to the world.

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Morse, R. P., and A. Mitchell-Innes. "The ineffectiveness of applying moisture to the ear on the incidence and severity of otic barotrauma for air passengers." Journal of Laryngology & Otology 132, no. 9 (September 2018): 790–95. http://dx.doi.org/10.1017/s0022215118001524.

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AbstractObjectiveThe application of moisture to the ear is anecdotally claimed to relieve the pain from otic barotrauma that can arise during aircraft descent. This claim was tested in a randomised double-blind study on an aircraft with eight participants heavily predisposed to barotrauma.MethodsOn the outward flight, half the participants wore ‘active’ devices that applied moisture to the external ear; the remainder wore placebo devices that contained no moisture, but were otherwise identical. On the return flight, the groups were reversed. Participants wore the devices from just before descent until landing, unless they experienced symptoms of barotrauma, in which case they switched to what they knew was an active device.ResultsThere were no significant differences between conditions regarding the appearance of the tympanic membrane on landing or the discomfort levels immediately before and after any switch.ConclusionApplying moisture is ineffective for passengers heavily predisposed to otic barotrauma.

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Caligari, P. D. S., W. Powell, and J. L. Jinks. "The use of double haploids for detecting linkage and pleiotropy between quantitatively varying characters in spring barley." Journal of Agricultural Science 106, no. 1 (February 1986): 75–80. http://dx.doi.org/10.1017/s0021859600061761.

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SUMMARYThe relationships between pairs of characters are investigated using F1 and F2 derived doubled haploids as well as single seed descent lines from spring barley (Hordeum vulgare) crosses. It is shown that linkage disequilibrium and pleiotropy are factors affecting the relationship between characters in barley. In fact, the linkages found are in general in the coupling phase and pleiotropy is usually positive. The consequences of such relations for plant breeding are discussed.

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Wang, K. F., Y. Q. Wang, B. L. Wang, and L. Zheng. "A double cantilever beam incorporating cohesive crack modeling for superconductors." Modern Physics Letters B 34, no. 15 (March 30, 2020): 2050166. http://dx.doi.org/10.1142/s0217984920501663.

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In this paper, a double cantilever beam (DCB) specimen incorporating cohesive crack is developed for superconductors which have potential applications in high temperature superconducting cables in space solar power station. The cohesive interface is introduced along the crack front of the DCB model under electromagnetic force. The load-separation relation (i.e. the crack opening displacement) is used as the fracture mechanics parameter and the corresponding curves during fracture process are obtained and verified by the finite element numerical method. Results show that the presence of tensile electromagnetic force makes crack propagate easily. Superconductors with small cracks have good adaptability to the oscillation of magnetic fields while that with large cracks are easier to fracture during the descent of the magnetic field. In addition, the ductility ratio of the cohesive interface can significantly increase the fracture strength. The length of fracture zone decreases as the crack length increases.

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Bleher, Pavel, and Alfredo Deaño. "Painlevé I double scaling limit in the cubic random matrix model." Random Matrices: Theory and Applications 05, no. 02 (April 2016): 1650004. http://dx.doi.org/10.1142/s2010326316500040.

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We obtain the double scaling asymptotic behavior of the recurrence coefficients and the partition function at the critical point of the [Formula: see text] Hermitian random matrix model with cubic potential. We prove that the recurrence coefficients admit an asymptotic expansion in powers of [Formula: see text], and in the leading order the asymptotic behavior of the recurrence coefficients is given by a Boutroux tronquée solution to the Painlevé I equation. We also obtain the double scaling limit of the partition function, and we prove that the poles of the tronquée solution are limits of zeros of the partition function. The tools used include the Riemann–Hilbert approach and the Deift–Zhou nonlinear steepest descent method for the corresponding family of complex orthogonal polynomials and their recurrence coefficients, together with the Toda equation in the parameter space.

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Hoorweg-Nijman, Jantine JG, Hester M. Havers, and Henriette A. Delemarre-van de Waal. "Effect of human chorionic gonadotrophin (hCG)/follicle-stimulating hormone treatment versus hCG treatment alone on testicular descent: a double-blind placebo-controlled study." European Journal of Endocrinology 130, no. 1 (January 1994): 60–64. http://dx.doi.org/10.1530/eje.0.1300060.

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Hoorweg-Nijman JJG, Havers HM, Delemarre-van de Waal HA. Effect of human chorionic gonadotrophin (hCG)/follicle-stimulating hormone treatment versus hCG treatment alone on testicular descent: a double-blind placebo-controlled study. Eur J Endocrinol 1994;1 30:60–4. ISSN 0804–4643 The medical treatment of retentio testis remains controversial because of ineffectiveness and/or adverse events. Follicle-stimulating hormone (FSH) seems to influence the spontaneous descent of the testis; furthermore, it induces luteinizing hormone (LH) receptors. Therefore, we performed a double-blind placebo-controlled study to investigate the effect of FSH with human chorionic gonadotrophin (hCG) versus hCG alone in retentio testis patients. Twenty-two boys with retentio testis were investigated, excluding retractile testis. Group A (N= 14: four with bilateral and 10 with unilateral retentio testis; mean age 3.1 5 years) was treated with 150 IU of FSH twice a week for 2 weeks followed by 1 50 IU of FSH and 250 IU of hCG (half the recommended World Health Organization dose) twice a week for another 4 weeks. Group B (N = 8: two with bilateral and six with unilateral retentio testis: mean age 3.3 years) was treated with 250 IU of hCG twice a week for 6 weeks. Testicular position, volume and consistency as well as the appearance of the scrotum and the penile length were determined at the start of the treatment as well as at weeks 2.4.6 and 12 by two independent investigators. Blood investigation consisted of measurements of LH, FSH, testosterone and sex hormone-binding globulin. Successful descent was considered when the testis reached a mid- or low scrotal position. In group A, 6/18 testes descended successfully. In group B, 6/10 testes descended. Of the unsuccessfully treated patients, six of group A and three of group B underwent surgery. Of these patients, 6/8 testes of group A and all testes of group B showed anatomical abnormalities, which could explain the lack of hormonal response. There were no significant differences in hormonal parameters between the two groups. In both groups no serious adverse events were mentioned or observed. In conclusion, half the recommended WHO dose of hCG is sufficient to reach successful descent in 43% of treated patients, with no serious adverse events; this response rate is in agreement with the literature. Follicle-stimulating hormone does not seem to have an additional effect on the success rate, and most of the unsuccessfully treated patients showed anatomical abnormalities at operation. JJG Hoorweg-Nijman, Department of Paediatrics, Free University Hospital. PO Box 7057, 1007 MB Amsterdam, The Netherlands

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Henreckson, David P. "Possessing Heaven in Our Head: A Reformed Reading of Incarnational Ascent in Kathryn Tanner." Journal of Reformed Theology 4, no. 3 (2010): 171–84. http://dx.doi.org/10.1163/156973110x542178.

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AbstractAs recent Reformed scholarship has turned its attention to the doctrine of creation, Kathryn Tanner can be engaged as an incisive and useful interlocutor. In her book Christ the Key, Tanner advances the notion of the double movement of divine descent and incarnate ascent, an idea which intersects with current Reformed deliberations on transcendence and the “chief end” of created humanity. Tanner’s re-articulation of the discussion of nature and grace, and divine agency within creation, offers a challenging and potentially constructive contribution to Reformed dogmatics.

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Belkin, Mikhail, Daniel Hsu, Siyuan Ma, and Soumik Mandal. "Reconciling modern machine-learning practice and the classical bias–variance trade-off." Proceedings of the National Academy of Sciences 116, no. 32 (July 24, 2019): 15849–54. http://dx.doi.org/10.1073/pnas.1903070116.

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Breakthroughs in machine learning are rapidly changing science and society, yet our fundamental understanding of this technology has lagged far behind. Indeed, one of the central tenets of the field, the bias–variance trade-off, appears to be at odds with the observed behavior of methods used in modern machine-learning practice. The bias–variance trade-off implies that a model should balance underfitting and overfitting: Rich enough to express underlying structure in data and simple enough to avoid fitting spurious patterns. However, in modern practice, very rich models such as neural networks are trained to exactly fit (i.e., interpolate) the data. Classically, such models would be considered overfitted, and yet they often obtain high accuracy on test data. This apparent contradiction has raised questions about the mathematical foundations of machine learning and their relevance to practitioners. In this paper, we reconcile the classical understanding and the modern practice within a unified performance curve. This “double-descent” curve subsumes the textbook U-shaped bias–variance trade-off curve by showing how increasing model capacity beyond the point of interpolation results in improved performance. We provide evidence for the existence and ubiquity of double descent for a wide spectrum of models and datasets, and we posit a mechanism for its emergence. This connection between the performance and the structure of machine-learning models delineates the limits of classical analyses and has implications for both the theory and the practice of machine learning.

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Cui, Chuyi, Ashwini Kulkarni, Shirley Rietdyk, and Satyajit Ambike. "Locomotion control during curb descent: Bilateral ground reaction variables covary consistently during the double support phase regardless of future foot placement constraints." PLOS ONE 17, no. 10 (October 5, 2022): e0268090. http://dx.doi.org/10.1371/journal.pone.0268090.

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During community ambulation, anticipatory adaptations in gait are key for navigating built, populated and natural environments. It has been argued that some instability in gait can be functionally beneficial in situations demanding high maneuverability, and while the mechanisms utilized to maintain locomotor balance are well understood, relatively less is known about how the control of gait stability changes to facilitate upcoming maneuvers in challenging environments. The double support phase may be important in this regard; since both feet can push off the ground simultaneously, there is greater control authority over the body’s movement during this phase. Our goal was to identify how this control authority is exploited to prepare for upcoming maneuvers in challenging environments. We used synergy indices to quantify the degree of coordination between the ground reaction forces and moments under the two feet for stabilizing the resultant force and moment on the body during the double support phase of curb descent. In contrast to our expectations, we observed that the kinetic synergy indices during curb descent were minimally influenced by expected foot targeting maneuvers for the subsequent step. Only the resultant moment in the frontal plane showed reduced stability when targeting was required, but the synergy index was still high, indicating that the resultant moment was stable. Furthermore, the synergy indices indicated that the main function of the ground reaction variables is to maintain stability of whole-body rotations during double support, and this prerogative was minimally influenced by the subsequent foot targeting tasks, likely because the cost of losing balance while descending a curb would be higher than the cost of mis-stepping on a visual target. Our work demonstrates the salience of stabilizing body rotations during curb negotiation and improves our understanding of locomotor control in challenging environments.

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Wang, Qian, Hongmei Li, Liguo Yang, Xianling Wang, and Wanjia Ye. "Predictive torque control of SMPMSM drive system based on extended control set and double gradient descent method." Journal of Physics: Conference Series 1754, no. 1 (February 1, 2021): 012231. http://dx.doi.org/10.1088/1742-6596/1754/1/012231.

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Zhao, Huiru, Yuwei Wang, Sen Guo, Mingrui Zhao, and Chao Zhang. "Application of a Gradient Descent Continuous Actor-Critic Algorithm for Double-Side Day-Ahead Electricity Market Modeling." Energies 9, no. 9 (September 9, 2016): 725. http://dx.doi.org/10.3390/en9090725.

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Ji, Miaoxin, Jinhao Liu, Xiangbo Xu, Yuyang Guo, and Zhenchun Lu. "Improved Pedestrian Positioning with Inertial Sensor Based on Adaptive Gradient Descent and Double-Constrained Extended Kalman Filter." Complexity 2020 (January 8, 2020): 1–11. http://dx.doi.org/10.1155/2020/4361812.

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The Foot-mounted Inertial Pedestrian-Positioning System (FIPPS) based on the Micro-Inertial Measurement Unit (MIMU) is a good choice for the forest fire fighters when the Global Navigation Satellite System is unavailable. Zero Velocity Update (ZUPT) provides a solution for reducing cumulative positioning errors caused by the integral calculation of the inertial navigation. However, the performance of ZUPT is highly affected by the low accuracy and high noise of the MIMU. The accuracy of conventional ZUPT for attitude alignment is reduced by the zero offset of acceleration and the drift of a gyroscope during the standing phase. An initial alignment algorithm based on Adaptive Gradient Descent Algorithm (AGDA) is proposed. In the stepping phase, the extended Kalman filter (EKF) is often used to correct attitude and position in track estimation. However, the measurement noise of the EKF is influenced by the high-frequency acceleration and angular velocity. Thus, the accuracy of the attitude and position will decrease. A double-constrained extended Kalman filtering (DEKF) is proposed. An adaptive parameter positively correlated with the acceleration and angular velocity is set, and the measurement noise in the DEKF is adaptively adjusted. The performance of the proposed method is verified by implementing the pedestrian test trajectory using MPU-9150 MIMU manufactured by InvenSense. The results show that the attitude error of the AGDA is 33.82% less than that of the conventional GDA. The attitude error of DEKF is 21.70% less than that of the conventional EKF. The experimental results verify the effectiveness and applicability of the proposed method.

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Pooni, H. S., J. L. Jinks, and D. Yohannes. "Comparison of inbred lines extracted from two single crosses and their double cross by single seed descent." Heredity 56, no. 2 (April 1986): 263–76. http://dx.doi.org/10.1038/hdy.1986.39.

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Duif, P. F. C. C. M., F. R. Leus, H. A. Kleinveld, and H. J. M. van Rijn. "The incidence of double-banded apo(a) phenotypes in a healthy normolipidemic Dutch population of Caucasian descent." Atherosclerosis 115 (June 1995): S89. http://dx.doi.org/10.1016/0021-9150(95)96589-k.

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Bigliardi, Prof Enrico, Carla Bresciani, Valeria De Cesaris, and Enrico Parmigiani. "A Rare Clinical Case Of Double Scrotum With Ectopic Testicle In a Dog." JOURNAL OF ADVANCES IN AGRICULTURE 4, no. 2 (June 15, 2015): 398–402. http://dx.doi.org/10.24297/jaa.v4i2.4270.

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A two-years old male mixed breed dog weighing 11 kg was brought to the Veterinary Teaching Hospital by its owner because he noticed a pigmented skin zone with a mass lateral to the penis. The patient was in good clinical condition. On clinical examination, only one testicle was found within the scrotum, and a mass lateral to the right site of the penis was present; upon palpation, the mass was presumed to be a testicle. An ultrasound examination confirmed the presence of an ectopic testicle in that position. The dog had normal fertility and testosterone levels were normal. The patient underwent bilateral orchiectomy and was discharged the following day. The peculiarity of this case is the presence of two independent scrota, an ectopic testicle and its adnexa passing through the abdominal wall, was not supposed to be due a migration along the typical male gonad path during descent.

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Niranjan, K., B. Srivani, and V. V. S. Naidu. "Daytime descending intermediate layers observed over a sub-tropical Indian station Waltair during low-solar activity period." Annales Geophysicae 28, no. 3 (March 18, 2010): 807–15. http://dx.doi.org/10.5194/angeo-28-807-2010.

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Abstract. Study on daytime descending intermediate layer over subtropical Indian station Waltair (17.7° N, 83.3° E geographic, 6.4° N, 10° E geomagnetic, 20° N dip) located in the equatorial anomaly transition region, using an IPS 42 Digital Ionosonde during the low solar activity year 2004 showed that the layers occur in the altitude range of 140–160 km with maximum occurrence during winter solstice. The layers observed during daytime occur with a double peak variation throughout the year with less occurrence probability and shorter duration presence during forenoon hours. The morning layer descent was associated with a density increase where as during afternoon hours a decrease in density was observed. The downward drift velocity was about 8 km/h during morning hours and between 7–11 km/h during afternoon hours, with a low descent rate of around 4.5 km/h during summer morning hours. The results indicate the presence of a 6 h tide at this location as observed from the characteristics of the descending layers, unlike at majority of locations where a significant semi diurnal trend is observed. The study brings out the complex nature of the tidal interaction at different locations.

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