619 research outputs found
Solitary wave refraction and diffraction by submerged ramps in the presence of ambient current
Application of BEMD in Extraction of Regional and Local Gravity Anomalies Reflecting Geological Structures Associated with Mineral Resources
The bi-dimensional empirical mode decomposition (BEMD) method is an adaptive analysis method for nonlinear and nonstationary data. With the sifting process of BEMD, the data can be decomposed into a series of bi-dimensional intrinsic mode functions (BIMFs), which may present the relative local feature of the data. In this study, the BEMD method was successfully used for analyzing the Bouguer gravity data of Gejiu tin-copper polymetallic ore field in Yunnan Province and Tongshi gold field in Western Shandong Uplift Block to extract different-scale anomalies. In these two cases, regional and local components were separated, which can reflect the geological structures at different depths and some intrusive bodies which may be associated with mineral deposits. The results reveals the spatial distribution relationship between the different intrusive bodies and the various types of mineral deposits in the aforementioned two study area, which provide some reliable evidence for exploration of new concealed mineral deposits
Monitoring of atopic dermatitis using leaky coaxial cable
In our daily life, inadvertent scratching may increase the severity of skin diseases (such as atopic dermatitis, etc.). However, people
rarely pay attention to this matter, so the known measurement behavior of the movement is also very little. Nevertheless, the behavior and
frequency of scratching represent the degree of itching, and the analysis of scratching frequency is helpful to the doctor's clinical dosage. In this
paper, a novel system is proposed to monitor the scratching motion of a sleeping human body at night. The core device of the system are just a
Leaky coaxial cable (LCX) and a router. Commonly, LCX is used in the blind field or semi blind field in wireless communication. The new idea is
that the leaky cable is placed on the bed, then the state information of physical layer of wireless communication channels is acquired to identify the
scratching motion and other small body movements in the human sleep process. The results show that it can be used to detect the movement and its
duration. Channel state information (CSI) packet is collected by card installed in the computer based on the 802.11n protocol. The characterization
of the scratch motion in the collected channel state information is unique, so it can be distinguished from the wireless channel amplitude variation
trend
Two-Dimensional Numerical Modelling of a Moored Floating Body under Sloping Seabed Conditions
publishedVersio
Scattering of long waves by freely oscillating submerged plates
We consider a horizontal, submerged plate in shallow water that is allowed to oscillate in the vertical direction due to the wave loads. The plate is attached to a linear spring and damper to control the oscillations. The focus of the study is on the transformation of the wave field by the submerged oscillating plate. To estimate energy scattering, wave reflection and transmission coefficients are determined from four wave gauges; two placed upwave and two placed downwave of the oscillating plate. The flow is governed by the nonlinear Level I Green-Naghdi (GN) equations, coupled with the equations of the vertical oscillations of the plate. Time series of water surface elevation recorded at gauges upwave and downwave of the plate obtained by the GN model are compared with the available laboratory experiments and other data, and very good agreement is observed. Wave reflection and transmission coefficients are then determined for a range of involved parameters, including wave conditions (wavelength and wave height), initial submergence depth of the plate, plate length, and the spring-damper system attached to the plate. It is found that a submerged oscillating plate can have a remarkable effect on the wave field, and that nonlinearity plays an important role in this wave-structure interaction problem. Discussion is provided on how the wave reflection and transmission coefficients vary with the wave conditions, plate characteristics, initial submergence depth and spring-damper system propertie
Wave Attenuation by Submerged Oscillating Plates
Submerged oscillating plates are used as heaving plates to reduce the motion of floating objects, in wave energy devices to extract the wave energy, and as break waters to attenuate the wave field in shallow water. In this study ,we consider a horizontal, submerged plate in shallow water that is allowed to oscillate in the vertical direction due to the wave loads. The plate is attached to a linear spring and damper to control the oscillations. The focus of this study is on the transformation of the wave field by the submerged oscillating plate. To estimate the energy attenuation, wave reflection and transmission coefficients are determined from four wave gauges; two placed upwave and two placed downwave of the oscillating plate. The fluid is governed by the nonlinear Level I Green-Naghdi (GN)equations, coupled with the equations of vertical motion of the plate to determine its oscillations. Time series of water surface elevation recorded at gauges upwave and downwave of the plate, and the wave-induced plate oscillations, obtained by the GN model are compared with available laboratory experiments and other data, and very good agreement is observed. Wave reflection and transmission coefficients are then determined for a range of involved parameters, including wave condition (wave height and wave period), initial submergence depth of the plate, plate length, and the spring-damper system. It is found that a single submerged oscillating plate can have remarkable effect on the wave field, and that nonlinearity plays an important role in this wave-structure interaction problem. Discussion is provided on how the wave reflection and transmission vary with the wave condition, plate characteristic, initial submergence depth and spring-damper system
Scattering of long waves by freely oscillating submerged plates
We consider a horizontal, submerged plate in shallow water that is allowed to oscillate in the vertical direction due to the wave loads. The plate is attached to a linear spring and damper to control the oscillations. The focus of the study is on the transformation of the wave field by the submerged oscillating plate. To estimate energy scattering, wave reflection and transmission coefficients are determined from four wave gauges; two placed upwave and two placed downwave of the oscillating plate. The flow is governed by the nonlinear Level I Green-Naghdi (GN) equations, coupled with the equations of the vertical oscillations of the plate. Time series of water surface elevation recorded at gauges upwave and downwave of the plate obtained by the GN model are compared with the available laboratory experiments and other data, and very good agreement is observed. Wave reflection and transmission coefficients are then determined for a range of involved parameters, including wave conditions (wavelength and wave height), initial submergence depth of the plate, plate length, and the spring-damper system attached to the plate. It is found that a submerged oscillating plate can have a remarkable effect on the wave field, and that nonlinearity plays an important role in this wave-structure interaction problem. Discussion is provided on how the wave reflection and transmission coefficients vary with the wave conditions, plate characteristics, initial submergence depth and spring-damper system propertie
- …