Effect of gamma-ray irradiation on magneto-optic characteristics of Cu-doped optical fiber was investigated. Verdet constant at 660 nm under magnetic field of 0.142 T of the optical fiber increased about 1.46 times af...
详细信息
ISBN:
(纸本)9784885522710
Effect of gamma-ray irradiation on magneto-optic characteristics of Cu-doped optical fiber was investigated. Verdet constant at 660 nm under magnetic field of 0.142 T of the optical fiber increased about 1.46 times after the irradiation.
We have developed a net-structure proximity sensor that detects the azimuth and elevation to a nearby object. This information can be used by robots to avoid obstacles or to respond to human behavior. We propose detec...
详细信息
ISBN:
(纸本)9781467363563
We have developed a net-structure proximity sensor that detects the azimuth and elevation to a nearby object. This information can be used by robots to avoid obstacles or to respond to human behavior. We propose detection principles where the azimuth is detected by arranging two one-dimensional net-structure proximity sensors along orthogonal axes, and the elevation is detected by arranging two one-dimensional net-structure proximity sensors in a stacked ring. We also experimentally demonstrate the feasibility of these detection principles. The experimental result shows the sensor can detect azimuth at all peripheral angles and elevation from side to top up.
An effective and robust soft recovery system for supersonic projectiles is required for the test of intelligent projectiles in development phase. The survivability of the projectiles after initial impact onto the targ...
详细信息
An effective and robust soft recovery system for supersonic projectiles is required for the test of intelligent projectiles in development phase. The survivability of the projectiles after initial impact onto the target is the most important requirement of them. A soft recovery system, consisting of multiple equally spaced metal plates, was designed and fabricated. Numerical simulations were performed to estimate the deceleration of the projectile after piercing through a thin steel plate with various speeds. Next, the thickness distribution of the plate for uniform deceleration could be designed. An aluminum foil sensor system was used to measure the arrival time of the projectile onto each plate and multi-channel time recording system for this test was developed. Field tests were done using a rifled barrel gun and a smooth bore gun. Deceleration data were acquired successfully. The trajectories of the projectile after the impact tended to veer off from the initial firing line with an increasing yaw angle. Deceleration increased with the increase of the yaw angle. Field data were used to design a final recovery system to retrieve the projectile with a minimum deceleration and damage.
This paper presents experimentally-verified multiphysics finite element model of a wideband vibration energy harvester with impact coupling, which operates on the principle of frequency up-conversion: under low-freque...
This paper presents experimentally-verified multiphysics finite element model of a wideband vibration energy harvester with impact coupling, which operates on the principle of frequency up-conversion: under low-frequency harmonic base excitation a cantilever-type resonator (with resonant frequency of 18.8 Hz) impacts a high-frequency piezoelectric cantilever, which starts freely vibrate at its resonant frequency of 374 Hz. Such input frequency amplification enables efficient power generation under low-frequency ambient excitations. The model was implemented in COMSOL and the contact between the cantilevers was formulated by using a nonlinear viscoelastic model. Reported results of dynamical and electrical testing of the fabricated vibration energy harvester confirm the accuracy of the model as well as reveal some operational characteristics of the device under varying impact and excitation conditions.
In this paper, a shared arm slot array is designed and its performance investigated for use in imaging radar. In constructing a physical array structure for near-field target sensing, spacing antenna elements may beco...
详细信息
ISBN:
(纸本)9781467310017
In this paper, a shared arm slot array is designed and its performance investigated for use in imaging radar. In constructing a physical array structure for near-field target sensing, spacing antenna elements may become problematic owing to the limited antenna spacing constraint for alias-free sampling in the aperture domain. The proposed shared arm slot array is designed such that two slot elements share a single slot arm, thereby achieving an alias-free sampling. In this paper, as a proof-of concept, a simplified 2-port array is designed, and its characteristic in radiation pattern is compared with a slot antenna, whose length of an arm is the same as the proposed 2-port array. Since the initial array shows a radiation pattern distortion, the geometry is modified to reduce the surface current at the unwanted slot arm. As a result, the modified array shows a corrected radiation pattern, allowing the structure to be useful in imaging radar applications.
The design and performance of steam generators supplied to thermal power plants are greatly influenced by the properties of coal burnt. All coals are not same and the variation of heating value of coal supplied to boi...
详细信息
This paper summarizes an initiative undertaken by PIEp, KTH and Stanford University to stimulate Swedish engineering faculty to embrace methods and tools for integrating creativity and innovation in higher engineering...
详细信息
This paper summarizes an initiative undertaken by PIEp, KTH and Stanford University to stimulate Swedish engineering faculty to embrace methods and tools for integrating creativity and innovation in higher engineering education. Ultimately, building on previous experiences of successful workshops held by PIEp and KTH within this context, the overall ambition is to establish a change in mindsets, and by so influencing key participants to directly leave endurable footprints onto their respective Swedish engineering education programs. The paper has a descriptive character blending 'best-of-both-worlds' concepts as it reveals how a nationwide Swedish initiative has set up a learning hub overseas together with Stanford University. Utilizing this source of entrepreneurial and inspiring environment the ambition is to equip Swedish faculty with experiences, success stories and lessons learned to enthusiasm and challenge existing program and curricula design. Overall, this paper entails the set-up, reflections and actions outlined by Swedish university representatives to address implementation of more transferability between innovation characteristics in respective education programs.
According to the special structure types and the operating requirements of long life, high stiffness, and low friction torque of thin walled bearing with crossed cylindrical rollers used for industrial robot, this pap...
详细信息
暂无评论