This paper studies Synthetic Aperture (SAR) images with the wavelets transform of lifting scheme, presents a new denoising method of wavelets analytic to reduce the coherent speckle noise. A lot of experiments approve that this new method not only suppresses the speckle noise effectively, but also preserves as many target characteristics of original images as possible. It shows that this denoising method offers a very attractive alternative to suppress the coherent speckle noise of the SAR images.

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Complete complementary sequence (CCS) has ideal correlation performance along the zero Doppler axis. However, its correlation property is extremely sensitive to the Doppler shift. In this letter, by employing a sequential quadratic programming (SQP) optimization method, a novel design of the Doppler resilient CCS is presented for multiple-input multiple-output (MIMO) . Compared to the existing methods, this design can reduce the range sidelobes associated with a matrix-valued ambiguity function without restrictions on the waveform number, the pulse number and the waveform length. In addition, the superior orthogonality of CCS can also be achieved. Several numerical examples are provided to demonstrate the effectiveness of this design.

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An iron-complexing antibiotic with a narrow spectrum of biological activity was produced by several strains of Aspergillus nidulans when grown in a low-iron, chemically defined medium. Its chemical and biological properties closely resembled those of desferritriacetylfusigen, a metabolite of several other Aspergilli and Penicillia.

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The range alignment approach is applied to solve the misalignment between the sampling clock and trigger pulse for signal acquisition system of pulse and Doppler (PD) . Adjacent pulse correlation (APC) and minimum entropy (ME) methods are utilized to suppress sidelobes and promote the detection performance. Experimental results have demonstrated the effectiveness of proposed methods.

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We conducted meteor echo observations using the Buckland Park MF (35°S, 138°E) at 00:40-05:45 LT on October 22, 1997. In addition to the usual full correlation analysis (FCA) technique to measure horizontal wind velocities from 60 to 100 km MF radars have a potential to detect meteor echoes and infer winds through their Doppler frequency shifts. Because of the relatively low radio frequency employed MF radars have a great advantage of providing meteor wind well above 100 km altitude, where very few techniques can measure wind velocities. There is a limitation which should be noted as well. The observations are possible only during night time when the electron density of E-region is low enough for the radio wave to penetrate into the upper region. We detected 233 underdense meteor echoes from 80 km to 120 km with a mean height of 104.4 km. Although the transmitting antenna beams were steered toward off-zenith angles of 25°, almost all the echoes were received outside of the main lobe, indicating that conventional MF systems with a broad transmitting beam can work well for meteor observations. Bi-hourly wind profiles were obtained from 94 to 114 km altitudes. The profiles revealed a clear wave structure with a downward phase progression with time. FCA winds from 80 to 100 km were also estimated, and a continuous wind structure was obtained from FCA to meteor heights. Note that the present observations happened to be conducted during a major meteor shower activity. However, a majority of the underdense echoes were from non-shower meteors, and observations during non-shower periods will also yield enough information.

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Low Probability of Intercept (LPI)

waveform has complex and diverse modulation schemes, which cannot be easily identified by the traditional methods. The research on intrapulse modulation LPI waveform recognition has received increasing attention. In this paper, we propose an automatic LPI waveform recognition algorithm that uses a multi-resolution fusion convolutional neural network. First, signals embedded within the noise are processed using Choi-William Distribution (CWD) to obtain time-frequency feature images. Then, the images are resized by interpolation and sent to the proposed network for training and identification. The network takes a dual-channel CNN structure to obtain features at different resolutions and makes features fusion by using the concatenation and Inception module. Extensive simulations are carried out on twelve types of LPI waveforms, including BPSK, Costas, Frank, LFM, P1~P4, and T1~T4, corrupted with additive white Gaussian noise of SNR from 10dB to -8dB. The results show that the overall recognition rate of the proposed algorithm reaches 95.1% when the SNR is -6dB. We also try various sample selection methods related to the recognition task of the system. The conclusion is that reducing the samples with SNR above 2dB or below -8dB can effectively improve the training speed of the network while maintaining recognition accuracy.

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A novel real-valued ESPRIT (RV-ESPRIT) algorithm is proposed to estimate the direction of arrival (DOA) and direction of departure (DOD) for noncircular signals in bistatic MIMO

. By exploiting the property of signal noncircularity and Euler's formula, a new virtual array data of bistatic MIMO , which is twice that of the MIMO virtual array data, is established with real-valued sine and cosine data. Then the receiving/transmitting selective matrices are constructed to obtain the receiving/transmitting rotationally invariant factors. Compared to the existing angle estimation methods, the proposed algorithm has lower computational load. Simulation results confirm the effectiveness of the RV-ESPRIT.

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This paper shows the actural circumstances of Japanese naval and their wartime urgent measures for . At the end of war Japanese naval was widely spread over. : about 250 land-based sites, 100 million yen costs, 30 types, 500 officers and 10 thousand operators. For the purpose of that, Japanese navies took the counter plan from the half time of the war. The main urgent measures of this are as follows. THe first, many young naval officers graduated from university got into the naval school which named Fujisawa Kaigun Densoku Gakkou (Naval School) established on September 1944 at Kanagawa Prefecture. The second, the new naval manufacture for named Numazu Kaigun Khosho (Navy Yard) established on June 1943 at Shizuoka Prefecture. The third, the was designed simply for the purpose of easy carriage, reasonable cost and long time operation. The typical was the Mark 1 Model 3 which was operating at 150 MHZ, peak power 10 KW. So many sites were constructed at pacific coasts of Japan, but there was no war with United States because of the Japanese primitive .

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Marine shaft power measurement is believed to assess the working condition for marine propulsion system. The traditional equipment uses battery-powered supply but could provide only 2-4 hours continuous monitoring time. To address this issue, a new shaft power measurement technique based on magnetic resonances is proposed in this paper. It was able to transfer 70mA over distances in the range of 5 to 20 millimeters. We experimentally demonstrated efficient power transfer over the self-resonant coils in the transmitter to the receiving end in order to achieve the transfer of energy. It is shown that the strain-type measurement using the magnetic resonances technique produces superior results to those using battery-powered measurements, and thus has application importance.

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It is very difficult work to evaluate numerically the complexity of images, although it communicates valuable information on the control of the systems and the recognition of the objects on images. In this paper, therefore, the numerical measurement of the complexity in echo distributions using fractal dimensions is proposed. Experimental results for real images show that this evaluation considerably agrees with the human sence for them and this simple value of the dimensions can reveal the complexity well. Also, the relationship between the fractal dimensions and gains, and the application of the fractal dimensions to the automatic recognition of the objects on images are presented.

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Recently, laser as a sensor to measure distance with a forward car is widely studied. The laser has a characteristic that the received signal becomes to be buried in noise with increasing distance. It is difficult to measure long distance with low laser power. Then, a new type of the chaos laser has been studied. This laser is relatively resistant to noise and can simply process because of using only add calculation. However, a distance resolution of the chaos laser is limited by clock cycle of FPGA which is used for signal processing of the laser . Therefore, a new method to improve a distance resolution by a phase delay circuit is developed. As a result, the distance resolution of chaos laser is improved to 1/10 using phase delay circuit.

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A new constant false alarm rate (CFAR) detection scheme based on the goodness-of-fit (GoF) test is proposed to deal with the problem of extended object detection in high resolution synthetic aperture (SAR) images. The performance of this detector is compared with that of the traditional detectors using the MSTAR database. Results show that the proposed detector is superior to the traditional detectors in controlling false alarms in nonhomogeneous environment where boundaries widely exist.

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simulator is used for the trainings of (1) positioning of own ship, (2) plotting of target ship and (3) collision avoidance action. The most important skill required in actual use is the ability to interpret correctly information or blips. For the purposes of training and improvement of this skill, the simulator training is conducted. As definite guide materials about simulator training, the IMO model course is well known. However, the model course is written basically for the person having their sea experiences, and this does not always coincide with present status in Japan. Because simulator training in Japan is usually carried out for beginners or students who have not or very short sea experience. So, an experiment for positioning training by a simulator was made in order to obtain basic data for proposing an effective training method for the beginners. positioning is required to execute speedy and accurately. Therefore, the evaluation of training must be judged from the speed and the accuracy in positioning. In this paper, the evaluation items are classified into the speed and accuracy, and the result of experiment that was analyzed quantitatively and qualitatively is discussed. From the result of the experiment, there were some tendencies such as (1) Briefing effect influences on the accuracy, (2) Learning effect by the repetition appears in the speed and (3) For beginners training, it is necessary to simulate the image faithfully as much as possible. Finally effect and problem of simulator training are also mentioned.

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The images of PPI echoes are different from the coastlines on the chart because the beam cannot arrive at the regions behind the hills or islands. In Naikai, many islands, hills and mountains are distributed near the recommended route and there are many narrow channels having strong tidal currents. If we meet the dens fog in such a channel, we must navigate by the informations of and lead our ship to the safety region. Therefor the navigator must determine the position by obsrving the scope at once. So we must have full knowledge about the characteristics of echoes in Naikai. We provided the pilot charts in Naikai along the recommended route, giving the important characteristics of echoes. Several of them are shown in this paper. It is said that if you train yourself by these pilot charts, you will easily be able to identify the echoes corresponding to any one point on the charts.

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The exact locations of 52 ground flash points of winter lightning were determined by VTR images taken from two observation sites. These optical observations of lightning flashs by VTR cameras had been carried out for about 40 days from November to December every year from 1985 to 1992 in Kahoku-Gata, a reclaimed flat land situated in the northern suburbs of Kanazawa, Japan. This land lays close to the Sea of Japan. Two kinds of meteorological echo diagrams are obtainable in this district, one being recorded by the Tojimbo of Meteorological Agency and the other by the Hotatsu-San of Ministry of Construction. The former is located at about 70km southwest and the latter at about 20km northeast of Kahoku-Gata. It is pointed out as a conspicuous feature that positions of the 52 ground flash points are all found on fringe of echo patterns obtained by the Tojimbo . As for 29 cases among them, the echo diagrams observed simulta-neously by both sites have been obtained. The echo distributions in the corresponding two echo-diagrams are similar to each other, but the details are different. Nevertheless, the ground flashes around Kahoku-Gata occurred on the fringe of echo patterns. Thus, when edge of the echo approaches to the important substation sites or transmission routes, any lightning flash to the ground might strike those power apparatus.

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In Japan, there are a lot of bridges connecting islands. Particularly in the Seto Inland Sea, several bridges are constructed near the narrow channels. When we pursue the safe operation of the vessels, we consider it important to analyze the masking features of the images of such bridges and the reflection intensity. In this study, we analyzed the features by the difference in the structure and the masking features along the direction of the width of the bridge and the reflection intensity about two bridges, in order to improve the safety of ships traffic. Conventionally, the reflection intensity of a small object such as a small ship has been evaluated by the maximum signal intensity in the image. In this study, we tried a new evaluation method for the reflection intensity of the connecting bridges those are huge and strong reflection structures, and we report the result.

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Today, laser is widely studied as in-car . The laser has a characteristic that the received signal becomes to be buried in noise with increasing distance. When the long distance is measured, it needs a high power laser, or the repetitive process that uses multiplication and integration. Therefore, a new type of the chaos laser has been studied. This laser is relatively resistant to noise and can simply process because of using only additional process. But, the chaos laser has been off-line processing thus far. Then using FPGA in the signal processing, the on-line measurement system is developed. As a result, the distance up to 95m can be measured on-line.

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 The dual-polarization (dual-pol) Doppler provides more information on precipitation particles compared with the traditional Doppler . In this study, the dual-pol observations of differential reflectivity (Z_DR), specific differential phase (K_DP), and radial velocity (VR) collected by the C-band Advanced for Meteorological and Operational Research are assimilated for a convective storm on June 23,2008. Two different warm-rain forward operators for Z_DR and K_DP data assimilation are built on the basis of empirical relationships between the dual-pol variables and water content in precipitation. The advanced research version of the Weather Research and Forecasting (WRF) model and three-dimensional variational (3DVAR) data assimilation system are used in this study. The main goal of this study is to demonstrate the sensitivity of initialization and prediction of a real case event to the dual-pol data assimilation with different forward operators. The results show that both forward operators successfully assimilate the Z_DR, K_DP, and VR data and help with the initialization and short-term forecast for the thunderstorm event. In addition, significant sensitivity caused by the use of different operators is found in the thermodynamic, kinematic, and microphysical fields of the storm, especially over the storm region. However, the storm location and movement are not largely influenced; hence, short-term precipitation forecast is not largely affected by the use of different operators.

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