82 research outputs found
Landslides Caused by Climate Change and Groundwater Movement in Permafrost Mountain
Climate change induced warming results in permafrost degradation. Melting permafrost subsequently leads to an increased incidence of landslides. The study area was within the northwest section of the Lesser Khingan Range in northern China along the Bei\u27an-Heihe Highway. We analyzed the impact of climate change on landslide movement in the permafrost zone via a combination of geological survey and meteorological data. The average annual temperature of the study area has increased by 3.2°C in last 60 years, and permafrost degradation is severe. Loose soil on the hillside surface provides appropriate conditions for the infiltration of atmospheric precipitation and snowmelt, and seepage from thawing permafrost. As it infiltrates downwards, water is blocked by the underlying permafrost or dense soil, and infiltrates along this barrier layer toward lower positions, forming a potential sliding zone. The combination of high density resistivity (HDR) methods based on soil resistivity values, ground-penetrating radar (GPR) methods based on characteristics of radar wave reflection, respectively, and geological drilling can be utilized to determine the regional stratigraphic distribution. This will allow the exact location of the landslide sliding surface to be precisely determined. Field test results indicate that radar reflectivity characteristics and the resistivity values of the soil in the landslide mass is significantly different from surrounding soil. There are sudden decreases in the apparent resistivity values at the sliding surface location. In addition, the radar exhibits strong reflection at the sliding surface position, with a sudden increase in the amplitude of the radar wave. Drilling results indicate that the soil has high water content at the location of the sliding surface of the landslide mass in the study area, which is entirely consistent with the GPR and HDR results. Thus, abnormal radar wave reflection and abrupt changes in apparent resistivity values can be used in practice to identify the location of landslide sliding surfaces in this region. We produce a detailed analysis of a representative landslide within the study area. Displacement monitoring locations were positioned at the trailing edge of the landslide mass and on the landslide mass surface. We then used this data to determine the relationships of landslide movement with both ground temperature and the trailing edge pore water pressure. The results suggest seasonal variation in the landslide movement process and characteristics of an annual cyclical trend. Landslide movement can be described by intermittence and low angles. The slip rate and the timing of slide occurrence exhibit relationships with the trailing edge pore water pressure of the landslide mass. The seepage of thaw water into the landslide mass will impact the trailing edge pore water pressure of the landslide mass. This phenomenon is identified as the primary cause of landslide movement
Lithium-Ion Battery Cell-Balancing Algorithm for Battery Management System Based on Real-Time Outlier Detection
A novel cell-balancing algorithm which was used for cell balancing of battery management system (BMS) was proposed in this paper. Cell balancing algorithm is a key technology for lithium-ion battery pack in the electric vehicle field. The distance-based outlier detection algorithm adopted two characteristic parameters (voltage and state of charge) to calculate each cell’s abnormal value and then identified the unbalanced cells. The abnormal and normal type of battery cells were acquired by online clustering strategy and bleeding circuits (R = 33 ohm) were used to balance the abnormal cells. The simulation results showed that with the proposed balancing algorithm, the usable capacity of the battery pack increased by 0.614 Ah (9.5%) compared to that without balancing
Mechanical transistors for logic-with-memory computing
As a potential revolutionary topic in future information processing,
mechanical computing has gained tremendous attention for replacing or
supplementing conventional electronics vulnerable to power outages, security
attacks, and harsh environments. Despite its potential for constructing
intelligent matter towards nonclassical computing systems beyond the von
Neumann architecture, most works on mechanical computing demonstrated that the
ad hoc design of simple logic gates cannot fully realize a universal mechanical
processing framework involving interconnected arithmetic logic components and
memory. However, such a logic-with-memory computing architecture is critical
for complex and persistent state-dependent computations such as sequential
logic. Here we propose a mechanical transistor (M-Transistor), abstracting
omnipresent temperatures as the input-output mechanical bits, which consists of
a metamaterial thermal channel as the gate terminal driving a nonlinear
bistable soft actuator to selectively connect the output terminal to two other
variable thermal sources. This M-Transistor is an elementary unit to modularly
form various combinational and sequential circuits, such as complex logic
gates, registers (volatile memory), and long-term memories (non-volatile
memory) with much fewer units than the electronic counterparts. Moreover, they
can establish a universal processing core comprising an arithmetic circuit and
a register in a compact, reprogrammable network involving periodic read, write,
memory, and logic operations of the mechanical bits. Our work contributes to
realizing a non-electric universal mechanical computing architecture that
combines multidisciplinary engineering with structural mechanics, materials
science, thermal engineering, physical intelligence, and computational science.Comment: 25 pages, 4 figures, Articl
The elicitor VP2 from Verticillium dahliae triggers defence response in cotton
Summary: Verticillium dahliae is a widespread and destructive soilborne vascular pathogenic fungus that causes serious diseases in dicot plants. Here, comparative transcriptome analysis showed that the number of genes upregulated in defoliating pathotype V991 was significantly higher than in the non‐defoliating pathotype 1cd3‐2 during the early response of cotton. Combined with analysis of the secretome during the V991–cotton interaction, an elicitor VP2 was identified, which was highly upregulated at the early stage of V991 invasion, but was barely expressed during the 1cd3‐2‐cotton interaction. Full‐length VP2 could induce cell death in several plant species, and which was dependent on NbBAK1 but not on NbSOBIR1 in N. benthamiana. Knock‐out of VP2 attenuated the pathogenicity of V991. Furthermore, overexpression of VP2 in cotton enhanced resistance to V. dahliae without causing abnormal plant growth and development. Several genes involved in JA, SA and lignin synthesis were significantly upregulated in VP2‐overexpressing cotton. The contents of JA, SA, and lignin were also significantly higher than in the wild‐type control. In summary, the identified elicitor VP2, recognized by the receptor in the plant membrane, triggers the cotton immune response and enhances disease resistance
A ‘Third Culture’ in Economics? An Essay on Smith, Confucius and the Rise of China
China's rise drives a growing impact of China on economics. So far, this mainly works via the force of example, but there is also an emerging role of Chinese thinking in economics. This paper raises the question how far Chinese perspectives can affect certain foundational principles in economics, such as the assumptions on individualism and self-interest allegedly originating in Adam Smith. I embark on sketching a 'third culture' in economics, employing a notion from cross-cultural communication theory, which starts out from the observation that the Chinese model was already influential during the European enlightenment, especially on physiocracy, suggesting a particular conceptualization of the relation between good government and a liberal market economy. I relate this observation with the current revisionist view on China's economic history which has revealed the strong role of markets in the context of informal institutions, and thereby explains the strong performance of the Chinese economy in pre-industrial times. I sketch the cultural legacy of this pattern for traditional Chinese conceptions of social interaction and behavior, which are still strong in rural society until today. These different strands of argument are woven together in a comparison between Confucian thinking and Adam Smith, especially with regard to the 'Theory of Moral Sentiments', which ends up in identifying a number of conceptual family resemblances between the two. I conclude with sketching a 'third culture' in economics in which moral aspects of economic action loom large, as well as contextualized thinking in economic policies
Interactive project review of deformable parts through haptic interfaces in Virtual Reality
Physical prototypes are increasingly replaced by virtual prototypes in the industrial implementation of Product Lifecycle Management. The design evaluation of an industrial deformable mechanical part plays a crucial role in term of validating its functional properties. From the industrial point of view, a deformable model formu- lated by the Finite Element Method is normally employed. However, the employment of the model is not straightforward for real-time interactions, especially when haptic interfaces are introduced into these deformation evaluation applications. Recently, a pre-computation approach based on the model reduction method was commonly used to reduce the real-time computational loads. The main goal of this thesis is to extend the pre-computation approach toward the design validation of deformable mechanical parts to investigate the trade-off issue between the deformation accuracy and the interaction performance. The key idea is to conceive techniques treating the off-line pre-computations and the on-line haptic interactions. Particularly, we develop a real-time deformation simulation framework by proposing a two-stage method combining an off-line phase and an on-line phase. During the off-line phase, we compute deformation spaces based on the modal analy- sis. The off-line pre-computations contribute to the modelling of a costless real-time deformation model which is suitable for haptic interactions. Furthermore, we propose an off-line mesh analysis method to pre-compute modal deformation spaces regard- ing the anticipated deformation evaluation scenarios. A real-time switch among these different spaces is developed so that the on-line deformation computations can focus on degrees of freedom where are necessary. During the on-line phase, we divide the real-time deformation computation process into two separate modules which are im- plemented on different threads to ensure the real-time haptic interaction performance. One module is dedicated to the haptic update task, which is implemented by extracting a sub-matrix from the pre-computed modal matrix, while the other module is dedicated to the deformation computation and visualization task. To verify the proposed method in the thesis, we carry out interaction experiments by interacting with different models with an increasing complexity. Experimental re- sults show that our method can efficiently handle the trade-off issue, as the deformation modelling is formulated by the finite element method which guarantees the deformation accuracy. And moreover, the heavy computations of large elastic systems are occurred off-line which assure a costless deformation response model in real-timePrototypes physiques sont de plus en plus remplacé par des prototypes virtuels dans la mise en {\oe}uvre industrielle de Product Lifecycle Management. L'évaluation de la conception d'une pièce mécanique industrielle déformable joue un rôle important en terme de validation de ses propriétés fonctionnelles. Du point de vue industriel, un modèle déformable formulées par la méthode des éléments finis est habituellement employée. Toutefois, l'emploi du modèle n'est pas simple en temps réel interactions, en particulier lorsque les interfaces haptiques sont introduits dans ces déformation demandes d'évaluation. Récemment, une approche de pré-calcul basé sur la méthode de réduction de modèle a été largement utilisée pour réduire les charges de calcul en temps réel. L'objectif principal de cette thèse est d'étendre l'approche de pré-calcul vers la validation de la conception de pièces mécaniques déformables pour enquêter sur la question de compromis entre l'exactitude de déformation et de la performance interaction. L'idée principale est de concevoir des techniques de traitement hors-ligne de pré-calculs et les interactions en ligne haptique. En particulier, nous développons un système de déformation en temps réel de simulation en proposant une méthode en deux étapes, associant une phase hors-ligne et une phase en ligne. Au cours de la phase hors-ligne, nous calculons la déformation des espaces basée sur l'analyse modale. Le hors-ligne de pré-calculs contribuer à la modélisation d'un modèle de déformation en temps réel sans coût qui convient à des interactions haptiques. En outre, nous proposons une méthode de maillage hors-ligne analyse de pré-calculer les espaces déformation modale en ce qui concerne les scénarios prévus évaluation déformation. Un interrupteur en temps réel entre ces différents espaces est développé de telle sorte que les calculs de déformation en ligne peuvent se concentrer sur les degrés de liberté où sont nécessaires. Au cours de la phase en ligne, nous divisons le processus de déformation en temps réel de calcul en deux modules distincts qui sont mis en {\oe}uvre sur différents processus pour assurer l'exécution interaction en temps réel haptique. Un module est consacré à la tâche de mise haptique, qui est mis en {\oe}uvre par l'extraction d'une sous-matrice de la pré-calculées matrice modale, tout en l'autre module est consacré au calcul de déformation et de la tâche de visualisation. Pour vérifier la méthode proposée dans cette thèse, nous réalisons des expériences d'interaction en interagissant avec les différents modèles avec une complexité croissante. Les résultats expérimentaux montrent que notre méthode peut traiter efficacement la question de compromis, que la modélisation de la déformation est formulée par la méthode des éléments finis qui garantit la précision de déformation. Et d'ailleurs, les calculs lourds de grands systèmes élastiques sont survenus hors ligne qui assurent un modèle de déformation sans coûts d'intervention en temps réel
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