Improving Angle-of-View for a 1-D Sensing Application by Using a 2-D Optical Sensor in “Cylindrical” Mode

Effect of photons and electrons on the over-response of optical fiber X-ray sensors

Sun image centroid algorithm is one of the key technologies of celestial navigation using sun sensors,which directly determine the precision of the sensors.Due to the limitation of centroid algorithm for non-circular sun image of the sun sensor of large field of view,firstly,the ellipse fitting algorithm is proposed for solving elliptical or sub-elliptical sun images.Then the spherical circle fitting algorithm is put forward.Based on the projection model and distortion model of the camera,the spherical circle fitting algorithm is used to obtain the edge points of the sun in the object space,and then the centroid of the sun can be determined by fitting the edge points as a spherical circle.In order to estimate the precision of spherical circle fitting algorithm,the centroid of the sun should be projected back to the image space.Theoretically,the spherical circle fitting algorithm is no longer need to take into account the shape of the sun image,the algorithm is more precise.The results of practical sun images demonstrate that the ellipse fitting algorithm is more suitable for the sun image with 70°~80.3°half angle of view,and the mean precision is about 0.075pixels;the spherical circle fitting algorithm is more suitable for the sun image with a half angle of view larger than 80.3°,and the mean precision is about 0.082 pixels.

Early life history stages in most marine animals are subject to high mortality through predation, starvation, and dispersal. Accordingly, the potential exists for the selection of behavioral mechanisms that reduce mortality. We examined the ecological significance of synchronization in hatch and the initiation of larval drift in rainbow smelt, Osmerus mordax, populations in St. Mary's Bay, Newfoundland. Larval abundances from six 24‐h ring net surveys (2‐h intervals) in Colinet and Salmonier Rivers during 2002/2003 suggest synchronized hatch following dusk (~2200 h). Monitoring of egg hatching in situ confirmed synchrony was at hatch and notemergence. Larval abundance showed no relationship with temperature or flow rates, and the consistency in hatch pattern suggested a light/dark cue. In experimental manipulations in which eggs were exposed to light and dark conditions for 2‐h periods, hatch percentages were up to five times higher (p < 0.005) in dark treatments. We hypothesized that the linkage of hatch to low light levels represents a mechanism to avoid elevated larval predation in daylight conditions. Egg predation determined from predator gut content analysis suggested that extreme predation risk from small (<20 cm) salmonids peaked during the day, prior to dusk, and was lowest during night (2200–0400 h). Microcosm experiments demonstrated that newly hatched larvae exposed to predators in dark conditionsdid not change in number, but mortality averaged 60% in light conditions. Our results suggest that predation pressure during the early life history of aquatic organisms might play a strong role in the optimization of aquatic life histories.

<i>Based on previous prototype of the Real time 3D holographic display developed last year, we developed a new concept of auto-stereoscopic multiview display (64 views), wide angle (90&deg;) 3D full color display. The display is based on a RGB laser light source illuminating a DMD (Discovery 4100 0,7”) at 24.000 fps, an image deflection system made with an AOD (Acoustic Optic Deflector) driven by a piezo-electric transducer generating a variable standing acoustic wave on the crystal that acts as a phase grating. The DMD projects in fast sequence 64 point of view of the image on the crystal cube. Depending on the frequency of the standing wave, the input picture sent by the DMD is deflected in different angle of view. An holographic screen at a proper distance diffuse the rays in vertical direction (60&deg;) and horizontally select (1&deg;) only the rays directed to the observer. A telescope optical system will enlarge the image to the right dimension. A VHDL firmware to render in real-time (16 ms) 64 views (16 bit 4:2:2) of a CAD model (obj, dxf or 3Ds) and depth-map encoded video images was developed into the resident Virtex5 FPGA of the Discovery 4100 SDK, thus eliminating the needs of image transfer and high speed links</i>

: Tests were conducted to evaluate the level of performance of commercially available optical fire detectors for use in Navy aircraft hangars. Detectors were evaluated based on response to fuel spill fires and to optical stresses (i.e., potential false alarm sources). The results of the fire detection evaluation have been combined with false alarm immunity criteria into a new optical detector performance specification for Navy aircraft hangars.

An ultra-wide-angle high-spatial-resolution high-spectral-resolution snapshot imaging spectrometer (UWA-2HSR-SIS) is presented, which comprises a microlens array (MLA), multiple fiber bundles, a micro-cylindrical-lens array (MCLA), a cylindrical lens, a static grating interferometer (SGI), and an area-array detector. The MLA is arranged in a circular arc of 120° or more. The MCLA is arranged in a straight line. The SGI includes a fixed reflection grating in Littrow configuration, a beam splitter, and a fixed plane mirror. Each fiber bundle containing multiple optical fibers is coupled to a separate microlens of the MLA, subdividing the field angle of each microlens into multiple smaller field angles. The light passing through each subdivided smaller field angle of each microlens of the MLA is received by a separate part of the detector. The UWA-2HSR-SIS is a new concept that not only obtains both high spatial resolution and high spectral resolution based on a single sensor for the first time, but also has an ultra-wide field angle in the horizontal plane, can obtain spectral information covering the full spectral range of interest in real time, and is very stable against various disturbances. The UWA-2HSR-SIS has great potential for remote sensing electro-optical reconnaissance sensors in the visible and near-infrared region.

A broadband high-spatial-resolution high-spectral-resolution flexible imaging spectrometer (B-2HSR-FIS) is presented, which includes two microlens arrays (MLAs), multiple fiber bundles, a scanning Fabry-Perot interferometer (FPI), a reflection grating, a cylindrical lens, and an area-array detector. The first MLA is arranged in a circular arc to obtain a field angle between 8° and 60° in the horizontal plane. The second MLA is arranged in a straight line. Each fiber bundle containing seven optical fibers is coupled to a separate microlens of the first MLA, subdividing the field angle of each microlens into seven smaller field angles to improve spatial resolution. The combination of a scanning FPI and a reflection grating enables the B-2HSR-FIS to obtain both high spectral resolution and broadband spectral range in the ultraviolet to near-infrared spectral region. Compared with all existing imaging spectrometers, the B-2HSR-FIS is the first to simultaneously obtain high spatial resolution, high spectral resolution, broadband spectral range, and moderate field angle, to the best of our knowledge. The B-2HSR-FIS has great potential for vision intelligence (e.g., as an eye of a robot).

The parallax barrier display system has excellent characteristics. For example, no special glasses are required. However, a conventional multi-view parallax barrier display system has disadvantages such that the resolution of each of the stereo images is reduced only horizontally. This paper describes a 4-view display with a parallax polarizer slit and cylindrical lenses. The advantage of proposed method lies in its ability to distribute resolution problem both to the horizontal and the vertical planes, then this three-dimensional (3-D) display avoids the horizontal resolution problem of conventional system.

The project proposes a Raspberry Pi-based system for real-time detection of lanes, obstacles, and traffic signals to improve road safety and assist drivers. The system uses computer vision algorithms and sensor data to provide situational awareness for vehicles. The lane detection module uses image processing to identify lane markings and estimate vehicle position, while the obstacle detection module uses visual and distance sensors to identify obstacles in the vehicle’s path. The traffic signal detection module uses image processing to identify and interpret traffic signals, helping drivers adhere to traffic regulations. The integration of these modules on a Raspberry Pi platform allows for compact deployment within vehicles, ensuring timely response to dynamic road conditions. This project offers a promising solution for intelligent transportation systems aimed at reducing accidents and improving traffic flow in urban environments. Key Words: Spotting,hough transform,obstascle detection,rasp cam,traffic signal detection,lane.

Aircraft engine's infrared lock-on range due to back pressure penalty from choked convergent nozzle

A point light source (PLS) display with enhanced viewing angle (VA) is proposed. The maximum VA of a conventional PLS display is equal to the propagation angle of the PLS, so a light-source array (3×3) was used to enlarge the propagation angle of the PLS in the horizontal and vertical directions. The number of converging elemental image points increases due to the large propagation angle of the PLS; thus, the VA of the integrated point was enhanced. From the experimental results, the VA of the proposed method was 2.6 times larger than the maximum VA of a conventional PLS display.

Electromagnetic Environment Associated with Lightning Strikes to Tall Strike Objects

兰州重离子加速器冷却储存环主环（CSRm）上成功应用了一种剩余气体电离剖面探测器（IPM），这种新型非拦截式剖面探测器的应用服役对CSRm的束流冷却研究及常规调束的实时剖面监测具有重要意义。IPM探测器通过收集束流与剩余气体之间的电离产物（气体离子或电子），利用偏转静电场将电离产物加速至多重微通道板（MCP），并在其上进行电子放大，放大的信号电子随后在荧光屏（P46等）上进行电子-光子转换，最终含有束流剖面信息的投影光子被真空靶室外的CCD相机获取。在正式应用于CSRm之前，IPM探测器还在分离扇回旋加速器直线（SSC Linac）上进行了束流实验，并与传统单丝扫描剖面探测器进行了对比。IPM探测器与单丝刮束器的剖面测量结果相近，并且具有较好的信噪比和约60 μm的较高空间分辨率。这种IPM探测器可以利用电阻串联进行均匀分压，较便捷地应用于真空度较低的直线加速器，还可以改造为分离电极单独供压的结构，应用在超高真空需要烘烤的环形加速器。最后还介绍了一种全新紧凑型结构的IPM探测器设计，该设计利用一套IPM探测器实现束流横向水平与垂直两个方向的剖面测量功能，这种紧凑型IPM结构尤其在空间紧缺型的强流直线加速器上具有重大的应用价值。 A new non-intercepting beam profile monitor, residual gas Ionization Profile Monitor (IPM), has been developed and tested at the main Cooling Storage Ring of Heavy Ion Research Facility in Lanzhou (HIRFL-CSRm). It has been successfully used for studies of electron cooling mechanisms, as well as profile monitoring under normal-mode operation in HIRFL-CSRm. The IPM measures the distribution of ions resulting from the residual gas ionization during the beam passage. The gas ions are collected and multiplied by tandem-type MCPs and a phosphor screen, and eventually captured by a commercial CCD camera outside the vacuum chamber. Before formally applied in HIRFL-CSRm, the IPM was tested and compared with a conventional wire scanner profile monitor at Sector Separated Cyclotron Linac (SSC Linac). Both results show good agreement. Besides, the IPM has higher signal to noise ratio than the wire scanner. It also has a very high spatial resolution of around 60 μm. This monitor can be used for low vacuum like Linac with resistance for bias voltage, or for ultra-high vacuum with discrete electrodes for bias voltage where the bakeout process is essential. Furthermore, a novel and compact design of one IPM with capability of detecting both horizontal and vertical profile is proposed. This compact IPM is quite suitable for non-invasive profile diagnostics at space shortage and high-current Linac.

Motivated by current experiments with ultracold atoms, the study of complex dynamics of Bose-Einstein condensates in optical lattices forms the central subject of this work. A lattice model of interacting bosons under the influence of an external force is motivated and derived from the experimental setup. Several dynamical regimes of this model are discussed in this thesis. In a first part we will develop a new measure for detecting avoided crossings in complex energy spectra and apply it to the quantum chaotic regime of the single-band system. The second and main part of this work is dedicated to the coupling between energy bands described in terms of a two-band model. The complex time evolution is already apparent in the horizontal and vertical population dynamics of the non-interacting problem. We find resonances in the interband transport, and, in a second step, study the effect of inter-particle interactions on these resonant oscillations. We are able to predict all time scales of the complex interband dynamics even in the presence of interactions. This is possible via the introduction of an effective model that is motivated and supported by a multitude of numerical results and proves exactly solvable.

Objective To explore the influence of vagus nerve stimulation (VNS) on inflammatory factors in serum and nucleus of the solitary tract, and hippocampal apoptosis in rats with depression induced by chronic unpredictable stress(CUS). Methods Totally 32 male Sprague Dawley (SD) rats aged 8-9 weeks were selected.Eight rats were chosen as control group, and the other 24 rats were treated as the depression model with CUS. The rats were randomly divided into CUS, fluoxetine and VNS group, with 8 rats in each group after successful modeling. The control group and CUS group were induced by normal saline. Fluoxetine group and VNS group were implanted with VNS stimulation electrode. The VNS stimulation lasted for 28 d. On the time points of before experiment, after modeling and after treatment, the sucrose consumption test and open-field test (OFT) were performed to observe the behavioral changes of rats. Elisa was used to detect the levels of TNF-α, IL-6 and IL-1β in serum and nucleus of the solitary tract. Cell apoptosis was observed with TUNEL staining in hippocampal CA1 region. Results (1) Sucrose consumption experiment and OFT showed that, compared with the CUS group, the consumption of sucrose, percentage of sucrose consumption, scores of vertical and horizontal movement increased significantly in the VNS group (consumption of sucrose: (11.78±2.67) ml, (8.06±2.85) ml; percentage of sucrose consumption: (72.31±9.98)%, (63.67±8.95)%; score of vertical movement: (16.61±3.98), (10.31±3.86); score of horizontal movement: (44.25±9.59), (36.21±7.21)) (t=4.87, 7.98, 5.87, 9.12, all P 0.05). (2) Compared with the CUS group, levels of TNF-α, IL-6 and IL-1β in serum decreased in the VNS group (serum TNF-α: (46.72±11.63) pg/ml, (125.47±15.18) pg/ml; serum IL-6: (243.65±38.90) pg/ml, (441.39±83.31) pg/ml; serum IL-1β: (209.31±32.45) pg/ml, (339.21±76.37) pg/ml) (t=-70.38, -196.25, -131.13, all P 0.05). Conclusion VNS can improve the depression behavior in rats with depression induced by CUS and the mechanism maybe related to inhibiting the expression of TNF-α, IL-6 and IL-1β in serum and nucleus of the solitary tract and cell apoptosis in hippocampal CA1 region. Key words: Chronic unpredictable stress; Vagus nerve stimulation; Nucleus of the solitary Tract; Inflammatory factors; Apoptosis; Rats