Journal articles: 'Typage bidirectionnel'

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Dunfield, Jana, and Neel Krishnaswami. "Bidirectional Typing." ACM Computing Surveys 54, no. 5 (June 2021): 1–38. http://dx.doi.org/10.1145/3450952.

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Bidirectional typing combines two modes of typing: type checking, which checks that a program satisfies a known type, and type synthesis, which determines a type from the program. Using checking enables bidirectional typing to support features for which inference is undecidable; using synthesis enables bidirectional typing to avoid the large annotation burden of explicitly typed languages. In addition, bidirectional typing improves error locality. We highlight the design principles that underlie bidirectional type systems, survey the development of bidirectional typing from the prehistoric period before Pierce and Turner’s local type inference to the present day, and provide guidance for future investigations.

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Wang, X., Y. X. Li, and Y. Liu. "Bidirectional solidification of radial-type porous magnesium." International Journal of Cast Metals Research 22, no. 1-4 (August 2009): 200–203. http://dx.doi.org/10.1179/136404609x367713.

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Khodabakhshian, Mina, Ehsan Adib, and Hosein Farzanehfard. "Forward‐type resonant bidirectional DC–DC converter." IET Power Electronics 9, no. 8 (June 2016): 1753–60. http://dx.doi.org/10.1049/iet-pel.2015.0975.

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Khedker, Uday P., Dhananjay M. Dhamdhere, and Alan Mycroft. "Bidirectional data flow analysis for type inferencing." Computer Languages, Systems & Structures 29, no. 1-2 (April 2003): 15–44. http://dx.doi.org/10.1016/s1477-8424(03)00012-5.

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Tseng, Hsu-Ting, and Jiann-Fuh Chen. "Bidirectional impedance-type transformer inrush current limiter." Electric Power Systems Research 104 (November 2013): 193–206. http://dx.doi.org/10.1016/j.epsr.2013.06.007.

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Lovas, William, and Frank Pfenning. "A Bidirectional Refinement Type System for LF." Electronic Notes in Theoretical Computer Science 196 (January 2008): 113–28. http://dx.doi.org/10.1016/j.entcs.2007.09.021.

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Wang, Zhenkun, Xianjin Su, Nianyin Zeng, and Jiahui Jiang. "Overview of Isolated Bidirectional DC–DC Converter Topology and Switching Strategies for Electric Vehicle Applications." Energies 17, no. 10 (May 20, 2024): 2434. http://dx.doi.org/10.3390/en17102434.

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Isolated bidirectional DC–DC converters are becoming increasingly important in various applications, particularly in the electric vehicle sector, due to their ability to achieve bidirectional power flow and their safety features. This paper aims to review the switch strategies and topologies of isolated bidirectional DC–DC converters, with a specific focus on their applications in the field of electric vehicles. From the perspective of topology, PWM-type isolated bidirectional DC–DC converters, dual active bridge converters, and resonant-type isolated bidirectional DC–DC converters constitute the three main categories of these converters. The paper further examines the traditional switch strategies of these converters and discusses how specific switch technologies, such as single-phase shift, expanding-phase shift, double-phase shift, and triple-phase shift, can enhance the overall performance of isolated bidirectional DC–DC converters. The paper meticulously examines the characteristics of each topology and control scheme, as well as their typical use cases in practical applications. Particularly, the paper delves into the applications of isolated bidirectional DC–DC converters in the electric vehicle sector and draws conclusions regarding their potential and trends in future electric vehicle technology.

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Jordis, Ulrich, Matthias Treu, and Stefan Welzig. "Bidirectional Conversion of Galanthamine and Crinine Type Heterocycles." HETEROCYCLES 55, no. 12 (2001): 2397. http://dx.doi.org/10.3987/com-01-9332.

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Chen, K. "Design of a Plane-Type Bidirectional Thermal Diode." Journal of Solar Energy Engineering 110, no. 4 (November 1, 1988): 299–305. http://dx.doi.org/10.1115/1.3268271.

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The design of a plane-type, bidirectional thermal diode is presented. This diode is composed of two vertical plates and several fluid-filled loops with their horizontal segments soldered to the vertical plates. This invention is simple in construction and low in cost. The direction of heat transfer in the invented thermal diode can be easily reversed. These features of the present invention make it very attractive to solar energy utilization. Natural convection analysis for thermosyphon operations was adopted for heat transfer calculations of the fluid-filled loops. A one-dimensional heat transfer analysis was employed to estimate the heat transfer rate and ratio of heat transfer rates of the diode under forward and reverse bias.

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Dognon, A. Yvette, K. Emile Aifa, H. F. Aristidina Aifa, and Lauretta Zinsou. "Tourisme et Croissance Inclusive au Bénin : Une Analyse d’Après l’Indice Synthétique de Croissance Inclusive." European Scientific Journal, ESJ 19, no. 31 (November 30, 2023): 170. http://dx.doi.org/10.19044/esj.2023.v19n31p170.

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Cette étude vise à examiner le type de relation entre tourisme et croissance inclusive au Bénin de 1995 à 2021 en utilisant comme variable dépendante, contrairement à plusieurs études, l’Indice Synthétique de Croissance Inclusive (ISCI). En nous appuyant sur des données chronologiques, nous avons effectué des estimations à l'aide du Modèle Vectoriel à Correction d'Erreur (VECM), du test de causalité de Granger et du Modèle à Correction d'Erreur (MCE) sous STATA 15. Les résultats révèlent une relation significative positive entre le ratio des recettes touristiques réelles et l'Indice Synthétique de Croissance Inclusive (ISCI), démontrant que le tourisme contribue à la croissance inclusive jusqu'à un seuil donné. En outre, la nature bidirectionnelle de cette relation (entre tourisme et croissance inclusive) a été également mise en évidence. This study aims to examine the type of relationship between tourism and inclusive growth in Benin from 1995 to 2021 using as a dependent variable, unlike several studies, the Synthetic Inclusive Growth Index (ISCI). Based on historical data, we carried out estimations using the Vector Error Correction Model (VECM), the Granger causality test and the Error Correction Model (ECM) under STATA 15. The results reveal a significant positive relationship between the ratio of real tourism receipts and the Synthetic Inclusive Growth Index (ISCI), demonstrating that tourism contributes to inclusive growth up to a given threshold. Furthermore, the bidirectional nature of this relationship (between tourism and inclusive growth) was also highlighted.

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Yan, Yih-Her, Hung-Liang Cheng, Shun-Yu Chan, Yu-Da Chen, and Yong-Nong Chang. "Design of an Isolated Bidirectional Symmetric Resonant Converter." Applied Sciences 10, no. 22 (November 17, 2020): 8144. http://dx.doi.org/10.3390/app10228144.

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An isolated type bidirectional resonant converter is presented in this paper. Using a dual active bridge as the main topology and integrating symmetric resonant mechanism, the developed converter features an isolated type bidirectional resonant converter with bidirectional power conversion and electrical isolation capabilities to ensure working security and stability. The application of a symmetric resonant scheme enables the control range of input and output voltages to be widened and achieves soft switching during bidirectional power conversion. A converter design process covering all the bases is exhibited in this work. With the digital signal processor (DSP) TMS320F28335 being employed as the control core, the developed isolated bidirectional resonant converter can effectively handle the power conversion between the simulated 400 V DC grid and the energy storage battery ranging from 280 to 403 V. Based on a 1 kW capacity design, the test data reveal that the forward conversion efficiency from grid to battery can reach 93.25%, and the reverse conversion efficiency from battery to grid is as high as 94.60%.

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Velmurugan, Periyakarupan, Sundarrajan Thiruvengadam, Vinoth Kumaravelu, Shrinithi Rajendran, Roshini Parameswaran, and Agbotiname Imoize. "Performance Analysis of Full Duplex Bidirectional Machine Type Communication System Using IRS with Discrete Phase Shifter." Applied Sciences 13, no. 12 (June 14, 2023): 7128. http://dx.doi.org/10.3390/app13127128.

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In this paper, passive Intelligent Reflecting Surface (IRS) is used to enhance the performance of a Full Duplex (FD) bidirectional Machine Type Communication (MTC) system with two source nodes. Each node is equipped with two antennas to operate in FD mode. In reality, self-interference and discrete phase shifting are two major impairments in FD and IRS-assisted communication, respectively. The self-interference at source nodes operating in FD mode is mitigated by increasing the number of meta-surface elements at the IRS. Bit Error Rate (BER) and outage performances are analyzed with continuous phase shifting and discrete phase shifting in IRS. Closed-form analytical expressions are derived for the outage probability and BER performances of the IRS-assisted bidirectional FD-MTC system with a continuous phase shifter. The outage and BER performances of the IRS-assisted bidirectional MTC system in the FD mode have Signal-to-Noise Ratio (SNR) improvement compared with the IRS-assisted bidirectional MTC system in Half Duplex (HD) mode, as the number of reflecting elements in IRS is doubled in the FD mode. The outage and BER performances are degraded by a discrete phase shifter. Hence, performance degradation of the proposed IRS-assisted bidirectional FD-MTC is examined for 1-bit shifter (0, π), 2-bit shifter (0, π/2, π, 3π/2), and for 3-bit shifter (0, π/4, π/2, 3π/4, π, 5π/4, 3π/2, 7π/4). The performance degradation when a discrete phase shifter is employed in IRS is compared with the ideal continuous phase shifter in IRS. Further, achievable rate analysis is carried out for finding the best location of the IRS in a bidirectional FD-MTC system.

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Jiang, Fan, Wei Ping Chen, and Zhong Wei Liang. "Bidirectional Fractal Test of Dust Particle." Advanced Materials Research 108-111 (May 2010): 954–59. http://dx.doi.org/10.4028/www.scientific.net/amr.108-111.954.

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To describe surface shape of the dust particle comprehensively, uses the bidirectional CCD to shoot picture of dust particle, through recognizing the bidirectional particle picture, matching the particle, computing the fractal results of identical particle in two pictures, and integrating two fractal results, obtains the dust particle bidirectional fractal. The results indicated that three fractal dimensions of spherical particle are quite closed, but the three fractal dimensions of flat type particle are significantly different.

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Teng, Zhiyang, and Yue Zhang. "Head-Lexicalized Bidirectional Tree LSTMs." Transactions of the Association for Computational Linguistics 5 (December 2017): 163–77. http://dx.doi.org/10.1162/tacl_a_00053.

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Sequential LSTMs have been extended to model tree structures, giving competitive results for a number of tasks. Existing methods model constituent trees by bottom-up combinations of constituent nodes, making direct use of input word information only for leaf nodes. This is different from sequential LSTMs, which contain references to input words for each node. In this paper, we propose a method for automatic head-lexicalization for tree-structure LSTMs, propagating head words from leaf nodes to every constituent node. In addition, enabled by head lexicalization, we build a tree LSTM in the top-down direction, which corresponds to bidirectional sequential LSTMs in structure. Experiments show that both extensions give better representations of tree structures. Our final model gives the best results on the Stanford Sentiment Treebank and highly competitive results on the TREC question type classification task.

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Wang, Peng, Ping Kang Li, and Ling Liang Kong. "Research on Comparison of Bidirectional Engaging Characteristic of a Novel Type Separable-Control Overrunning Clutch." Applied Mechanics and Materials 556-562 (May 2014): 1367–71. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.1367.

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To broaden the application scope of the controllable overrunning clutch, a novel type Separable-Control Overrunning Clutch (SCOC) used in vehicle system has been designed by the authors of this paper. With the special axial arranged structure, the clutch has bidirectional engaging ability and its both sides could be chosen as the driving end. In order to analysis and compare the bidirectional engaging characteristics of the clutch, a nonlinear dynamics model taking into account clearance and elastic contact has been established by ADAMS. Through the simulations, a series of comprehensive summary on the bidirectional engaging characteristic has been drawn and it could provide theoretical guidance for further prototype design and experimental research. Project supported by National Natural Science Foundation of China (Grant No. : 61074104 )

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Ahamed, M. Ejas, and S. Senthilkumar. "Review of Bidirectional DC-DC Converters." International Journal of Advance Research and Innovation 5, no. 4 (2017): 33–42. http://dx.doi.org/10.51976/ijari.541706.

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There is a growing importance in bidirectional dc-dc converters for interface battery with energy source. This paper provides a comprehensive review of non-isolated bidirectional dc-dc converter topologies. The classification and explanation of each type of converter is based on the features and applications. This review paper is intended as a convenient reference to future bidirectional dc-dc converter users. The most promising converters in terms of their simplicity, flexibility, and high efficiency are singled out.

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Bannister, Roger A., Symeon Papadopoulos, Claudia S. Haarmann, and Kurt G. Beam. "Effects of inserting fluorescent proteins into the α1S II–III loop: insights into excitation–contraction coupling." Journal of General Physiology 134, no. 1 (June 29, 2009): 35–51. http://dx.doi.org/10.1085/jgp.200910241.

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In skeletal muscle, intermolecular communication between the 1,4-dihydropyridine receptor (DHPR) and RYR1 is bidirectional: orthograde coupling (skeletal excitation–contraction coupling) is observed as depolarization-induced Ca2+ release via RYR1, and retrograde coupling is manifested by increased L-type Ca2+ current via DHPR. A critical domain (residues 720–765) of the DHPR α1S II–III loop plays an important but poorly understood role in bidirectional coupling with RYR1. In this study, we examine the consequences of fluorescent protein insertion into different positions within the α1S II–III loop. In four constructs, a cyan fluorescent protein (CFP)–yellow fluorescent protein (YFP) tandem was introduced in place of residues 672–685 (the peptide A region). All four constructs supported efficient bidirectional coupling as determined by the measurement of L-type current and myoplasmic Ca2+ transients. In contrast, insertion of a CFP–YFP tandem within the N-terminal portion of the critical domain (between residues 726 and 727) abolished bidirectional signaling. Bidirectional coupling was partially preserved when only a single YFP was inserted between residues 726 and 727. However, insertion of YFP near the C-terminal boundary of the critical domain (between residues 760 and 761) or in the conserved C-terminal portion of the α1S II–III loop (between residues 785 and 786) eliminated bidirectional coupling. None of the fluorescent protein insertions, even those that interfered with signaling, significantly altered membrane expression or targeting. Thus, bidirectional signaling is ablated by insertions at two different sites in the C-terminal portion of the α1S II–III loop. Significantly, our results indicate that the conserved portion of the α1S II–III loop C terminal to the critical domain plays an important role in bidirectional coupling either by conveying conformational changes to the critical domain from other regions of the DHPR or by serving as a site of interaction with other junctional proteins such as RYR1.

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Zhao, Guanxiao, and Tao Fu. "A Unit Compound Structure Design: Poisson’s Ratio Is Autonomously Adjustable from Negative to Positive." Materials 16, no. 5 (February 22, 2023): 1808. http://dx.doi.org/10.3390/ma16051808.

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The shape memory polymer (SMP) is a new type of smart material that can produce a shape memory effect through the stimulation of the external environment. In this article, the viscoelastic constitutive theory of the shape memory polymer and the mechanism of the bidirectional memory effect of the shape memory polymer are described. A chiral poly cellular circular concave auxetic structure based on a shape memory polymer made of epoxy resin is designed. Two structural parameters, α and β, are defined, and the change rule of Poisson’s ratio under different structural parameters is verified by ABAQUS. Then, two elastic scaffolds are designed to assist a new type of cellular structure made of a shape memory polymer to autonomously adjust bidirectional memory under the stimulation of the external temperature, and two processes of bidirectional memory are simulated using ABAQUS. Finally, when a shape memory polymer structure implements the bidirectional deformation programming process, a conclusion is drawn that changing the ratio β of oblique ligament and ring radius has a better effect than changing the angle α of oblique ligament and horizontal in achieving the autonomously adjustable bidirectional memory effect of the composite structure. In summary, through the combination of the new cell and the bidirectional deformation principle, the autonomous bidirectional deformation of the new cell is achieved. The research can be used in reconfigurable structures, tuning symmetry, and chirality. The adjusted Poisson’s ratio achieved by the stimulation of the external environment can be used in active acoustic metamaterials, deployable devices, and biomedical devices. Meanwhile, this work provides a very meaningful reference for the potential application value of metamaterials.

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Mesinovic, Jakub, Ayse Zengin, Barbora De Courten, Peter R. Ebeling, and David Scott. "Sarcopenia and type 2 diabetes mellitus: a bidirectional relationship." Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy Volume 12 (July 2019): 1057–72. http://dx.doi.org/10.2147/dmso.s186600.

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Ma, Y., De Yu Wang, R. X. Xie, M. Wang, and Y. H. Yan. "Occurrence of bidirectional type III bursts in solar flares." Astrophysics and Space Science 318, no. 1-2 (October 22, 2008): 87–92. http://dx.doi.org/10.1007/s10509-008-9899-z.

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Sampol, Gabriel, and Albert Lecube. "Type 2 diabetes and the lung: A bidirectional relationship." Endocrinología y Nutrición (English Edition) 59, no. 2 (February 2012): 95–97. http://dx.doi.org/10.1016/j.endoen.2012.02.003.

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Sawiński, Albert, Piotr Chudzik, and Karol Tatar. "SMC Algorithms in T-Type Bidirectional Power Grid Converter." Energies 17, no. 12 (June 17, 2024): 2970. http://dx.doi.org/10.3390/en17122970.

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In this paper, the implementation of sliding mode control algorithms for the case of power grid current regulation in a T-type bidirectional inverter system connected via an LCL filter to the power grid is proposed and presented. A mathematical model of such a system has been proposed, which was then implemented in a simulation environment. The method of designing sliding controllers using the Lyapunov method to conduct a stability proof is presented. The article includes a comparative analysis of two sliding mode control algorithms: the classic one, which includes equivalent control, discontinuous part, and proportional reaching law, and the hybrid one, in which the discontinuous part and reaching law were modified.

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Song, Weizhang, Jiang Liu, Xiangdong Sun, Fenjun Wu, Daqing Gao, and Youyun Wang. "Research on Commutation and Coordination Control Strategy of Excitation Power Supply Based on Bidirectional Reduced Matrix Converter for Ion Accelerator." Energies 11, no. 12 (December 4, 2018): 3396. http://dx.doi.org/10.3390/en11123396.

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The contribution of this paper is putting forward a kind of ion accelerator magnet excitation power supply with bidirectional reduced matrix converter (BRMC) as well as a coordination control strategy with bipolar current space vector modulation strategy, which is utilized to realize bidirectional power flow for a BRMC system to solve problems such as low input power factor, large input current harmonics and no bidirectional energy in the conventional ion accelerator magnet excitation power supply. Meanwhile, a hybrid commutation strategy combining the simplified three-step commutation with zero vector commutation was proposed to solve the commutation problem for a matrix-type first stage in BRMC. The feasibility and effectiveness of the proposed strategy, which can achieve bidirectional energy flow and safer commutation, have been verified by the experimental results.

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Chilimoniuk, Zuzanna, Maciej Dobosz, Aleksandra Chałupnik, Aleksandra Borkowska, and Grzegorz Mizerski. "The bidirectional relationship between depression and diabetes." Journal of Education, Health and Sport 12, no. 3 (March 15, 2022): 67–77. http://dx.doi.org/10.12775/jehs.2022.12.03.006.

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Introduction and objective: In recent years, depression and diabetes have become more and more serious medical issues. The number of patients suffering from one or both of these disorders increases year by year, which significantly worsens their quality of life. The aim of the study is to present the current state of knowledge on the basic mechanisms and risk factors influencing the development of depression in patients with diabetes, as well as the bidirectional relationship between these illnesses. The study was based on a literature review and an analysis of publications available on PubMed and Google Scholar platforms. The search has been conducted with the use of a combination of keywords like: “diabetes type 1”, “diabetes type 2”, “depression”, “mental health”. An abbreviated description of the state of knowledge: Every third patient with diabetes shows depressive symptoms. These psychological disorders are more common in people with type 1 diabetes. The most vulnerable group of patients are single women with low socioeconomic status and comorbidities. Numerous biochemical and psychosocial changes in the life of diabetic patients, significantly increase the risk of developing depression. The latest scientific reports also draw attention to the two-way relationship between diabetes and depression. The inclusion of cognitive-behavioral therapy brings positive results in managing diabetes with comorbid depression. Summary: The available scientific data clearly shows the existence of psychological and biological links between these two disease entities. Appropriate diagnosis and treatment of depressive disorders can improve the course of diabetes.

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Kim, Kuk-Hyeon, Bo-Chan Hwang, Tuan-Vu Le, Seong-Mi Park, Chang-Ho Lee, and Sung-Jun Park. "Bi-Directional Converter System for Light Load by Heterogeneous Combined Type Reactor." Electronics 11, no. 18 (September 15, 2022): 2924. http://dx.doi.org/10.3390/electronics11182924.

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In this paper, we propose a new type of smoothing reactor using different types of reactors with different magnetic flux saturation to construct a DC-DC converter with low current ripple under the light load of the bidirectional DC-DC converter. Reduction of current ripple at light load in the limited hybrid reactor can greatly reduce the inrush current ripple of DC-Grid at light load, which is a weakness of existing bidirectional DC-DC converters and is considered to contribute to DC-Grid stabilization. Experiments were conducted to prove the feasibility of the proposed system and hybrid reactor.

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Sang, Xue, Zongguo Zhang, Hongwei Yang, and Xiaofeng Han. "Exact Traveling Wave Solutions of the Local Fractional Bidirectional Propagation System Equations." Fractal and Fractional 6, no. 11 (November 5, 2022): 653. http://dx.doi.org/10.3390/fractalfract6110653.

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In this paper, within the scope of the local fractional derivative theory, bidirectional propagation system local fractional equations are researched. Compared with the unidirectional propagation of nonlinear waves in a pipeline, the bidirectional propagation system equations studied in this paper can better describe the propagation of nonlinear waves in a channel. This study is groundbreaking and offers more possibilities for the bidirectional propagation of nonlinear waves in the simulation pipeline. The exact traveling wave solutions of the non-differentiable type defined on the Cantor sets are obtained. The characteristics of the particular solutions of a fixed fractal dimension are discussed. It is proven that the local fractional nonlinear bidirectional wave equations can describe the interaction of fractal waves. It is also shown that the study of traveling wave solutions of nonlinear local fractional equations has important significance in mathematical physics.

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Lou, Xi Yin. "Research of Track-Type Full Feeding Combine Harvester Walking Design Scheme Based on Hydraulic Close System." Applied Mechanics and Materials 697 (November 2014): 187–89. http://dx.doi.org/10.4028/www.scientific.net/amm.697.187.

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Hydraulic technology is one of the key techniques of modern transmission and control. Closed type hydraulic power transmission system is weight ratio, fast action, easy to realize the advantages of flexible stepless speed regulation, flexible power transmission. In this paper, the closed hydraulic system of double bidirectional variable hydraulic pump and the bidirectional quantitative motor, the drive system for crawler type machinery, advantages, in the walking system design process can reasonable calculation and power matching, reasonable selection of power components, the universal value of engineering application.

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Xue, Xu, and Bruno C. d. S. Oliveira. "Contextual Typing." Proceedings of the ACM on Programming Languages 8, ICFP (August 15, 2024): 880–908. http://dx.doi.org/10.1145/3674655.

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Bidirectional typing is a simple, lightweight approach to type inference that propagates known type information during typing, and can scale up to many different type systems and features. It typically only requires a reasonable amount of annotations and eliminates the need for many obvious annotations. Nonetheless the power of inference is still limited, and complications arise in the presence of more complex features. In this paper we present a generalization of bidirectional typing called contextual typing . In contextual typing not only known type information is propagated during typing, but also other known information about the surrounding context of a term. This information can be of various forms, such as other terms or record labels. Due to this richer notion of contextual information, less annotations are needed, while the approach remains lightweight and scalable. For type systems with subtyping, contextual typing subsumption is also more expressive than subsumption with bidirectional typing, since partially known contextual information can be exploited. To aid specifying type systems with contextual typing, we introduce Q uantitative T ype A ssignment S ystem s (QTASs). A QTAS quantifies the amount of type information that a term needs in order to type check using counters. Thus, a counter in a QTAS generalizes modes in traditional bidirectional typing, which can only model an all (checking mode) or nothing (inference mode) approach. QTASs enable precise guidelines for annotatability of contextual type systems formalized as a theorem. We illustrate contextual typing first on a simply typed lambda calculus, and then on a richer calculus with subtyping, intersection types, records and overloading. All the metatheory is formalized in the Agda theorem prover.

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Nilsson, M., A. Brandenburg, A. C. Andersen, and S. Höfner. "Unidirectional polymerization leading to homochirality in the RNA world." International Journal of Astrobiology 4, no. 3-4 (October 2005): 233–39. http://dx.doi.org/10.1017/s1473550405002752.

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The differences between unidirectional and bidirectional polymerization are considered. The unidirectional case is discussed in the framework of the RNA world. Similar to earlier models of this type, where polymerization was assumed to proceed in a bidirectional fashion (presumed to be relevant to peptide nucleic acids), left- and right-handed monomers are produced via an autocatalysis from an achiral substrate. The details of the bifurcation from a racemic solution to a homochiral state of either handedness is shown to be remarkably independent of whether the polymerization is unidirectional or bidirectional. Slightly larger differences are seen when dissociation is allowed and the dissociation fragments are recycled into the achiral substrate.

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Belghuith, S., S. Daoud, N. Smaoui, N. Farhat, S. Sakka, O. Hdiji, K. S. Moalla, M. Damak, M. Maalej Bouali, and C. Mhiri. "The bidirectional relationship between epilepsy and depression." European Psychiatry 64, S1 (April 2021): S339. http://dx.doi.org/10.1192/j.eurpsy.2021.910.

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IntroductionThe relationship between epilepsy and depression has been recognized for a long time. In fact, the presence of depression could worsen the disease outcome.Objectiveswe aimed to study the prevalence of depression in patients with epilepsy and to assess the determinant factors of its genesis.Methods54 patients with epilepsy, aged more than 18 years, attending the neurology department of Habib Bourguiba Hospital, Sfax, Tunisia, were enrolled for the study. All patients were administered Mini-International Neuropsychiatric Interview (MINI) for evalution of psychiatric comorbid disorders especially depression. Socio-demographic and clinical data were collected.ResultsA total of 54 patients were included, of whom 63% (n =34) were men. Mean duration of epilepsy was 20.13 years. The most frequent type of seizure was generalized 72.7%. Depression was present in 7.3 % of patients. Alcoholism (p=0.027) was significantly associated with occurrence of depression. Drug resistence (p = 0.03) and longer duration of epilepsy (p = 0.046) were significantly associated with occurrence of depression. No significant association was found between type of seizure, seizure frequency, medication compliance and depression. Depression wasn’t associated with anti-epileptic drug. We didn’t find any association between depression and other psychiatric comorbidities.ConclusionsDepression wasn’t frequent in our study contrary to literature. The possible explanations are the reduced simple size and the sensitivity of the used tool to assess depression in epilepsy. Pursuant to literature, we found significant association between Alcoholism, drug resistance and long duration of epilepsy.

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Nakamura, Eri. "The bidirectional CSR investment – economic performance relationship." Journal of Global Responsibility 6, no. 1 (May 11, 2015): 128–44. http://dx.doi.org/10.1108/jgr-05-2014-0021.

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Purpose – This paper aims to investigate the following two research questions: Do corporate social responsibility (CSR) investments enhance a firm’s economic performance? Does the firm’s economic performance influence CSR investments? That is, the bidirectional relationship between CSR investments and economic performance. Design/methodology/approach – This paper analyzes three types of CSR investments (environmental, labor-related and social investments) using a simultaneous equations model with a data set of 185 Japanese firms. Findings – Environmental investments reduce economic performance, labor-related investments do not significantly affect economic performance and social investments increase economic performance. Moreover, strong economic performance decreases environmental investments but increases social investments. Labor-related investments are chosen considering economic performance in both the present and previous terms. Practical implications – For managers, environmental and labor-related investments are not effective for improving economic performance. However, eradicating them completely might harm corporate reputation. In contrast, social investments have now become important. For policymakers, different approaches may be adopted to encourage firms to increase CSR investments. In some cases, policymakers can rely on firm initiatives instead of regulating or encouraging CSR activities. Originality/value – First, the authors empirically examine the bidirectional relationship between CSR investments and economic performance. Second, they clarify the determinants of CSR by specifying the investment function of each type of CSR. Third, they consider three types of CSR investments, with interrelations among them allowed in the model, and determine how each type affects firm performance.

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Allen, EM, JB Matthews, R. O'Connor, D. O'Halloran, and ILC Chapple. "Periodontitis and Type 2 Diabetes: Is Oxidative Stress the Mechanistic Link?" Scottish Medical Journal 54, no. 2 (May 2009): 41–47. http://dx.doi.org/10.1258/rsmsmj.54.2.41.

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Periodontitis is a common, chronic inflammatory disease initiated by bacteria which has an increased prevalence and severity in patients with type 2 diabetes. Recent studies indicate that the co-morbid presence of periodontitis can, in turn, adversely affect diabetic status and the treatment of periodontitis can lead to improved metabolic control in diabetes patients. Current evidence points to a bidirectional interrelationship between diabetes and inflammatory periodontitis. The importance of oxidative stress-inflammatory pathways in the pathogenesis of type 2 diabetes and periodontitis has recently received attention. Given the bidirectional relationship between these two conditions, this review discusses the potential synergistic interactions along the oxidative stress-inflammation axis common to both type 2 diabetes and periodontitis, and the implications of this relationship for diabetic patients.

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Yuan, Chunxin, and Zhan Wang. "Bidirectional Whitham type equations for internal waves with variable topography." Ocean Engineering 257 (August 2022): 111600. http://dx.doi.org/10.1016/j.oceaneng.2022.111600.

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Huang, Weiqing, Junkai Lian, Mingyang Chen, and Dawei An. "Bidirectional Active Piezoelectric Actuator Based on Optimized Bridge-Type Amplifier." Micromachines 12, no. 9 (August 26, 2021): 1013. http://dx.doi.org/10.3390/mi12091013.

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Piezoelectric actuators based on bridge displacement amplifying mechanisms are widely used in precision driving and positioning fields. The classical bridge mechanism relies on structural flexibility to realize the return stroke, which leads to the low positioning accuracy of the actuator. In this paper, a series bridge mechanism is proposed to realize a bidirectional active drive; the return stroke is driven by a piezoelectric stack rather than by the flexibility of the structure. By analyzing the parameter sensitivity of the bridge mechanism, the series actuation of the bridge mechanism is optimized and the static and dynamic solutions are carried out by using the finite element method. Compared with the hysteresis loop of the piezoelectric stack, the displacement curve of the proposed actuator is symmetric, and the maximum nonlinear error is improved. The experimental results show that the maximum driving stroke of the actuator is 129.41 μm, and the maximum nonlinear error is 5.48%.

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CHOI, Wonsung, Dongmin IM, Min Sik PARK, Young-Gyoon RYU, Seung Sik HWANG, Yong Su KIM, Hyunjin KIM, Seok-Gwang DOO, and Hyuk CHANG. "Keggin-type Polyoxometalates as Bidirectional Redox Mediators for Rechargeable Batteries." Electrochemistry 84, no. 11 (2016): 882–86. http://dx.doi.org/10.5796/electrochemistry.84.882.

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Skolnik, P. R., B. R. Kosloff, and M. S. Hirsch. "Bidirectional Interactions Between Human Immunodeficiency Virus Type 1 and Cytomegalovirus." Journal of Infectious Diseases 157, no. 3 (March 1, 1988): 508–14. http://dx.doi.org/10.1093/infdis/157.3.508.

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Demirel, Onur, Ugur Arifoglu, and Kemal Kalayci. "Novel three‐level T‐type isolated bidirectional DC–DC converter." IET Power Electronics 12, no. 1 (January 2019): 61–71. http://dx.doi.org/10.1049/iet-pel.2018.5680.

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Sun, Dongming, Sheng Wang, Junpei Sakurai, Seiichi Hata, Kee-Bong Choi, and Akira Shimokohbe. "A Traveling Wave Type of Piezoelectric Ultrasonic Bidirectional Linear Microactuator." Applied Physics Express 2 (April 3, 2009): 046503. http://dx.doi.org/10.1143/apex.2.046503.

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Everson-Rose, S. A. "Bidirectional association between elevated depressive symptoms and type 2 diabetes." Evidence-Based Mental Health 12, no. 1 (February 1, 2009): 24. http://dx.doi.org/10.1136/ebmh.12.1.24.

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Lim, K. S., J. J. Lee, S. Lee, and H. S. Kang. "Low-cost coaxial-type single TO-can bidirectional optical subassembly." Electronics Letters 46, no. 23 (2010): 1556. http://dx.doi.org/10.1049/el.2010.2344.

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Yang, Yu-wei, Chen-ning Zhang, Yi-jia Cao, Yu-xia Qu, Tian-yi Li, Tian-ge Yang, Di Geng, and Yi-kun Sun. "Bidirectional regulation of i-type lysozyme on cutaneous wound healing." Biomedicine & Pharmacotherapy 131 (November 2020): 110700. http://dx.doi.org/10.1016/j.biopha.2020.110700.

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Zou, Jinhao, Rajesh Talluri, and Sanjay Shete. "Approaches to estimate bidirectional causal effects using Mendelian randomization with application to body mass index and fasting glucose." PLOS ONE 19, no. 3 (March 8, 2024): e0293510. http://dx.doi.org/10.1371/journal.pone.0293510.

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Mendelian randomization (MR) is an epidemiological framework using genetic variants as instrumental variables (IVs) to examine the causal effect of exposures on outcomes. Statistical methods based on unidirectional MR (UMR) are widely used to estimate the causal effects of exposures on outcomes in observational studies. To estimate the bidirectional causal effects between two phenotypes, investigators have naively applied UMR methods separately in each direction. However, bidirectional causal effects between two phenotypes create a feedback loop that biases the estimation when UMR methods are naively applied. To overcome this limitation, we proposed two novel approaches to estimate bidirectional causal effects using MR: BiRatio and BiLIML, which are extensions of the standard ratio, and limited information maximum likelihood (LIML) methods, respectively. We compared the performance of the two proposed methods with the naive application of UMR methods through extensive simulations of several scenarios involving varying numbers of strong and weak IVs. Our simulation results showed that when multiple strong IVs are used, the proposed methods provided accurate bidirectional causal effect estimation in terms of median absolute bias and relative median absolute bias. Furthermore, compared to the BiRatio method, the BiLIML method provided a more accurate estimation of causal effects when weak IVs were used. Therefore, based on our simulations, we concluded that the BiLIML should be used for bidirectional causal effect estimation. We applied the proposed methods to investigate the potential bidirectional relationship between obesity and diabetes using the data from the Multi-Ethnic Study of Atherosclerosis cohort. We used body mass index (BMI) and fasting glucose (FG) as measures of obesity and type 2 diabetes, respectively. Our results from the BiLIML method revealed the bidirectional causal relationship between BMI and FG in across all racial populations. Specifically, in the White/Caucasian population, a 1 kg/m2 increase in BMI increased FG by 0.70 mg/dL (95% confidence interval [CI]: 0.3517–1.0489; p = 8.43×10−5), and 1 mg/dL increase in FG increased BMI by 0.10 kg/m2 (95% CI: 0.0441–0.1640; p = 6.79×10−4). Our study provides novel findings and quantifies the effect sizes of the bidirectional causal relationship between BMI and FG. However, further studies are needed to understand the biological and functional mechanisms underlying the bidirectional pathway.

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Chen, Jiaqi, Jieyun Mao, Hongbo Shi, and Xikun Wang. "Experimental and Numerical Study on the Hydraulic Characteristics of an S-Type Bidirectional Shaft Tubular Pump." Journal of Marine Science and Engineering 10, no. 5 (May 14, 2022): 671. http://dx.doi.org/10.3390/jmse10050671.

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In order to study the characteristics of a bidirectional shaft tubular pump with S-type symmetric airfoil blades, a prototype model was designed, manufactured, and tested. The energy characteristics, cavitation characteristics, and runaway characteristics of the pump were obtained under forward and reverse operating conditions for five different blade angles. Based on the basic equations of the pump and the inlet and outlet velocity triangles, combined with model tests and numerical simulations, the hydraulic performance of the pump was extensively analyzed and evaluated. In addition, semi-empirical equations for reverse efficiency and runaway characteristics were proposed. The dynamic pressure-drop coefficients were introduced to compare the cavitation performance under different flow rates in forward and reverse operations. The results reveal that the efficiency of the pump in reverse operation is greater than that of forward operation only under a very small flow rate. While the cavitation performance of the bidirectional pump in the two operating modes is almost the same, the runaway speed and backflow rate in forward operation are considerably greater than those of reverse operation. The results provide an important reference for the safe and stable operation of bidirectional shaft tubular pumps.

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Lef, M. R., K. F. Yarn, C. C. Chen, and W. R. Chang. "GaAs Triac-like Triangular Barrier Switch Prepared by Molecular Beam Epitaxy." Active and Passive Electronic Components 24, no. 1 (2001): 1–11. http://dx.doi.org/10.1155/2001/29392.

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A new S-shaped negative differential resistance (NDR) switching device, prepared by molecular beam epitaxy (MBE), has been successfully developed in a GaAs double triangular barrier structure. Symmetrical bidirectional S-shaped NDR characteristics are observed experimentally. The bidirectional current-voltage (I–V) characteristics exhibit a new type of NDR caused by an avalanche multiplication process in reverse biased base-collector region and barrier redistribution. Under a base current injection with respect to the cathode, the device exhibits a conventional transistor with a current gain of 1.2 at room temperature. The experimentally electrical results can be easily understood by an equivalent circuit. In addition, a new optoelectronic switching device is also proposed which may have the potential for bidirectional wave length emission.

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Alsharif, Haifa Nasser S., Jawharah Ali Y. Mari, Rawan Saeed A. Shafloot, Ghydaa Sultan H. Alhufayyan, Ghadah Khaled Bahamdan, and Mukhatar Ahmed Javali. "Awareness of the bidirectional relationship between diabetes, periodontal diseases, and its risk factors among diabetic patients in the Asir region, Saudi Arabia." Saudi Journal of Oral Sciences 10, no. 2 (May 2023): 83–90. http://dx.doi.org/10.4103/sjoralsci.sjoralsci_14_23.

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Introduction: Bidirectional relationship between diabetes and periodontal diseases has been recognized and accepted in the literature for a long time and shown to influence each other in both development and disease progression. Age, obesity, stress, smoking, and genetic predisposition are considered risk factors for diabetes and periodontal diseases. Aims: The objective of this questionnaire study was to assess the awareness of diabetic patients regarding the bidirectional relationship between diabetes, periodontal diseases, and risk factors. Materials and Methods: A cross-sectional questionnaire study was conducted on diabetic patients in the Asir region of Saudi Arabia between 18 and 70 years-age group individuals. A self-administrated questionnaire, which contained four sections of close-ended questions, was used. The sections included demographic characteristics, knowledge, and awareness regarding the relationship between diabetics and periodontal disease and knowledge and understanding of oral hygiene. SPSS version 20 was used to analyze the collected data, and descriptive statistical analysis was done. Results and Discussion: This study included 221 diabetic patients. The overall knowledge regarding the bidirectional relationship was high among 43%, whereas the knowledge regarding oral hygiene was high among 58.8%. The duration of diabetes (P = 0.006), medication for controlling blood sugar (P = 0.03), type of medication (P = 0.004), and the state of diabetes (P = 0.01) significantly affected the knowledge regarding the bidirectional relationship. There was a significant correlation between the understanding of oral hygiene and the knowledge of the bidirectional relationship (P = 0.0001). Conclusions: The study participants had low knowledge and awareness regarding the bidirectional relationship between diabetes and periodontal disease. However, those who had a high knowledge of oral hygiene also had an increased knowledge regarding the bidirectional correlation. Medical and dental professionals must create awareness about the importance of maintaining good oral health and influencing overall general health in diabetic patients, regardless of the presence or absence of the recognized risk factors.

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Mohd Noh, NZ, MFH Hidayat, F. Ariffin, E. Noor, and FH Al-Bayaty. "Interdisciplinary Approach Involving Medical Colleagues in Managing Periodontitis Patient with Type 2 Diabetes: A Case Report." Compendium of Oral Science 9, no. 1 (January 13, 2022): 86. http://dx.doi.org/10.24191/cos.v9i1.16914.

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Introduction: Diabetes mellitus has been recognized as a systemic risk factor for periodontitis. Success in controlling periodontitis requires interdisciplinary solutions involving medical counterparts. Case report: This case report highlights the importance of a bidirectional communication between medical and periodontal specialist in the management of a 63-year-old Malay lady patient diagnosed with Generalized Periodontitis, Stage IV and Grade C. The outcome of the interdisciplinary approach was both the stabilization of her periodontal conditions and medically, the glycated haemoglobin level. Conclusions:The bidirectional communication between medical and periodontal specialist is as important as managing the patients medically for a holistic treatment approach of an uncontrolled diabetic patient.

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Wan, Nana, and Xu Chen. "Multiperiod Production and Ordering Policies for a Retailer-Led Supply Chain through Option Contracts." Mathematical Problems in Engineering 2018 (2018): 1–17. http://dx.doi.org/10.1155/2018/9097136.

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This paper formulates two groups of multiperiod production and ordering models with call and bidirectional option contracts for a two-party supply chain consisting of one followed supplier and one dominant retailer, respectively. Based on dynamic programming theory, we characterize the optimal policy structures for two partners in each period. We also provide an approximation for the corresponding policy parameters evaluation in two cases. Then, we investigate the impacts of different option contracts and the demand risk on the decisions and performances of two members. Our results suggest that, whether concerning call or bidirectional option contracts, the optimal policies for two members always follow a base stock type. When the price parameters are the same for different option contracts, the service levels of both the system and the retailer are higher with call option contracts than with bidirectional ones, whereas the retailer’s inventory risk is lower with bidirectional option contracts than with call ones. Under the same conditions stated above, call option contracts can always benefit the supplier, but not the retailer. Owing to the retailer’s dominant position, call option contracts are better choice for the supply chain if the option (exercise) price is low (high), while bidirectional option contracts are more suitable choice for the supply chain if the option (exercise) price is high (low). In addition, an increase in the demand risk would prompt the supplier to increase his production quantity and the retailer to reduce the initial firm order quantity, either with call or bidirectional option contracts.

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Minja, Aleksandar, Dušan Dobromirov, and Vojin Šenk. "Bidirectional stack decoding of polar codes." Vojnotehnicki glasnik 69, no. 2 (2021): 405–15. http://dx.doi.org/10.5937/vojtehg69-29858.

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Introduction/purpose: The paper introduces a reduced latency stack decoding algorithm of polar codes, inspired by the bidirectional stack decoding of convolutional codes and based on the folding technique. Methods: The stack decoding algorithm (also known as stack search) that is useful for decoding tree codes, the list decoding technique introduced by Peter Elias and the folding technique for polar codes which is used to reduce the latency of the decoding algorithm. The simulation was done using the Monte Carlo procedure. Results: A new polar code decoding algorithm, suitable for parallel implementation, is developed and the simulation results are presented. Conclusions: Polar codes are a class of capacity achieving codes that have been adopted as the main coding scheme for control channels in 5G New Radio. The main decoding algorithm for polar codes is the successive cancellation decoder. This algorithm performs well at large blocklengths with a low complexity, but has very low reliability at short and medium blocklengths. Several decoding algorithms have been proposed in order to improve the error correcting performance of polar codes. The successive cancellation list decoder, in conjunction with a cyclic redundancy check, provides very good error-correction performance, but at the cost of a high implementation complexity. The successive cancellation stack decoder provides similar error-correction performance at a lower complexity. Future machine-type and ultra reliable low latency communication applications require high-speed low latency decoding algorithms with good error correcting performance. In this paper, we propose a novel decoding algorithm, inspired by the bidirectional stack decoding of classical convolutional codes, with reduced latency that achieves similar performance as the classical successive cancellation list and successive cancellation stack decoding algorithms. The results are presented analytically and verified by simulation.

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Lingyu, Meng, Li Hongguang, Zhang Mingdong, Li Na, and Liu Yahui. "Aminotransferases as causal factors for metabolic syndrome: A bidirectional Mendelian randomization study." PLOS ONE 19, no. 4 (April 25, 2024): e0302209. http://dx.doi.org/10.1371/journal.pone.0302209.

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Background Circulating aminotransferases (ALT and AST) have been used as biomarkers for liver injury. The causal relationships between aminotransferases and metabolic syndrome remain ambiguous. Methods We conducted bidirectional and multivariable Mendelian randomization (MR) analyses between aminotransferases and traits related to metabolic syndrome using genetic variants obtained from genome-wide association studies (GWASs). MR-PRESSO tests were adopted to remove outliers and eliminate pleiotropy. MR steiger tests were conducted to ensure the correct direction of the causal effects. Results Both aminotransferases were risk factors for essential hypertension. ALT is a risk factor for type 2 diabetes. The bidirectional causal relationship between ALT and hyperglycemia, serum lipids, and obesity was demonstrated. The effect of fasting glucose on AST was demonstrated, while type 2 diabetes did not affect AST. The effect of HDL-C on ALT and the effect of triglycerides on AST were found in multivariable MR analyses. Conclusions Our bidirectional MR analyses suggest that ALT and AST are causally associated with several metabolic syndrome-related traits, especially hypertension and type 2 diabetes. These findings highlight the potential role of aminotransferases as biomarkers and therapeutic targets for metabolic syndrome.

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Segal, Yoav, Liyan Zhuang, Eric Rondeau, Jean-Daniel Sraer, and Jing Zhou. "Regulation of the Paired Type IV Collagen GenesCOL4A5andCOL4A6." Journal of Biological Chemistry 276, no. 15 (November 28, 2000): 11791–97. http://dx.doi.org/10.1074/jbc.m007477200.

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Tissue-specific expression patterns of the paired type IV collagen genesCOL4A5andCOL4A6form the basis for organ involvement in X-linked Alport syndrome, a disorder in which these genes are mutated. We investigated the proximal promoter region ofCOL4A5andCOL4A6using glomerular visceral epithelial cells, in whichCOL4A5alone is transcribed; keratinocytes, in which the genes are co-transcribed; and additional model cell lines. By RNase protection assays, the intergenic region is 292 base pairs. Transcription start sites for two 5′ splice variants ofCOL4A6are 1 kilobase apart. Transient transfections with reporter gene constructs revealed that the minimal promoters forCOL4A5andCOL4A6are within 100 base pairs of their respective transcription start sites and are functionally distinct. In further transfection, gel shift and footprinting assays, we defined a bidirectional positive regulatory element, which functions in several cell types, but not in glomerular visceral epithelial cells selectively transcribingCOL4A5. The existence of separate promoters forCOL4A5andCOL4A6permits fine control over their expression. Activation through the bidirectional element can bring about co-expression of the genes, exploiting their paired arrangement. Features of the proximal promoter region frame its roles in a hierarchy regulating type IV collagen gene expression.

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Journal articles on the topic 'Typage bidirectionnel'

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