Dynamic Change Information Research Articles

Remote Sensing Monitoring Research of Multi-Temporal Desertfication Based on Spectral Mixture Analysis: A Case Study of Wuda, Inner Mongolia, China

Using three TM images of 1991, 2004 and one OLI image of 2014 as data sources, we extracted dynamic change information of desertification land during 23 years in Wuda district in Inner Mongolia, discussed spatio-temporal evolution processes of desertification land of this area aiming to provide decision-making references for desertification control and eco-environmental restoration and reconstruction. Abundance Maps of sand, vegetation, water and low albedo were derived based on linear spectral mixture analysis (SMA). Owing to the nice correlation between vegetation abundance and vegetation coverage, vegetation abundance was used to extract desertification land types. The results show that, during the past of 23 years, the total desertification area decreased by 114.23 square kilometers, particularly for the extremely severe desertification. The reducing desertification land mostly transformed into non-desertified land, such as water, coal and residential region, due to human intensive development activities.

Bird Species Identification Based on Timbre and Pitch Features of Their Vocalization

Although wild bird watching has been a popular leisure activity, it is often the case that people have no idea about what kind of bird species they see or hear. To help people learn to identify bird species, this study proposes an automatic bird sound identification system. Considering bird vocalization can be generally divided into two categories, namely call and song, the proposed system is built upon a two-stage identification framework. The first stage performs call/song classification. If an unknown sound clip is classified as a call, it is then handled by a call identifier in the second stage; otherwise, it is handled by a song identifier. Both identifiers use two acoustic features, timbre and pitch, to determine which of the bird species the sound clip belong to. In using timbre features, bird sounds are converted into Mel-Frequency Cepstral Coefficients and their first derivatives and then analyzed using Gaussian mixture models. In using pitch feature, we convert bird sounds into MIDI note sequences and then use bigram models to analyze the dynamic change information of the notes. Our experiments, conducted using a database including twenty common bird species in the Taipei urban area, show that the proposed system can achieve 90.4% accuracy.

China Offshore Data Translation Net and Information Integration and Release Platform

China offshore marine observation station of Chinese academy of sciences consists of dozens of marine observation buoy system, which are spread in China's offshore to obtain the long-term continuous oceanographic elements. In order to get the real-time understanding of marine dynamic change information, the observed data need to be translated back on time to the terrestrial laboratory and the scientists can analyze them. By the communication way of general packet radio service(GPRS), code division multiple access(CDMA) and “Beidou” satellite, a large range of data transmission network of covering China offshore area is formed and the real-time observation data and the buoy state information is transmitted to ground-based data station. In ground-based station, the data received software is compiled and installed, which make the data are received and displayed. In addition, in order to better use the data, original database is needed and the primary data products are formed. At the same time network information release, establish data sharing mechanism. It is mature database software, established the real-time database and delay database, they have abundant data query function, but were established based on the Internet data information release and communication system, to scientists and government decision makers, fishery breeding personnel and the public users provide different levels of data information products for its service, and provide an exchange platform.

THE APPROACH TO DYNAMIC CHANGE INTERPRETATION FROM REMOTE SENSING IMAGE ON THE BASIS OF DOUBLE-EDGE TECHNIQUE

There are many approaches to the extraction of dynamic change information from remote sensing imagery. However, their operations are very cumbersome, and their efficiency is not so ideal. Double-edge seems to be a good solution. Double edge refers to the boundaries between the neighboring objects or parts in remote sensing image, with the width of its boundary being two pixels, and it can be described by two raster lines. It helps to interpret the objects in remote sensing image by the region of double-edge and to understand the features of dynamic changes by the colors of the double-edge. The procedure for interpretation of dynamic changes based on double-edge is simple and convenient, and the technique contributes to cutting down the work load and reducing the interpretation errors. This paper presents the principles and application of this approach, and makes the information extraction test for land use changes from remote sensing image.

A STUDY OF LAND DESERTIFICATION DYNAMIC CHANGE IN YELLOW RIVER BASIN

Dynamic change information of land desertification in the Yellow River Drainage Area was extracted from remote sensing images of three different periods,which include MSS(1975),TM(1990) and ETM(2000).Investigation shows that land desertification mainly occurred in the northwestern part and the area of land desertification increased 10 653.22 km2 from 1975 to 2000,i.e.,about 426.12 km2 per year.It was the geological and climate conditions that controlled the distribution and dynamic change trend of land desertification.In addition,improper human activity accelerated the desertification trend.

Study of remote sensing monitoring of dynamic change of the Loess Plateau forest resources

Taking for example Daning County, a key pilot area of “the Three North Protection Forest Project” in China’s Loess Plateau, this article is to explore the method of using remote sensing technology to monitoring the dynamic change information of forest vegetation. It uses LANDSAT TM, CBERS-1 data and aerial remote sensing and ground investigation to monitoring the dynamic change of forest vegetation information of Daning County in three different periods – 1978, 1987 and 2000. The results of the research prove that, this method is worth widely popularized, by which the dynamic change information of the forest vegetation can be monitored simply and quickly so as to explore a scientific, rational and effective road for us to rectify the territory of China’s Loess Plateau, change the poor physiognomy of this area, improve the ecological environment and promote the development of national economy.

Visually guided locomotion in the gerbil: a comparison of open- and closed-loop control

Two experiments were conducted in order to explore the effects of visual feedback on control of locomotion in the gerbil. In the first experiment, gerbils were trained to run down an alleyway towards a visual target in order to obtain food reward. One group of animals was trained to run to a target whose size never varied while another group was trained to run to a target whose size varied randomly from trial to trial. On some trials, the target’s size was changed dynamically during running to determine whether gerbils used this dynamic size change information to compute time to collision (tau). Results suggested that neither group used retinal image size information but both groups seemed able to compute tau. In a second experiment, gerbils were trained in the same way as in experiment 1, but on some trials the target was extinguished during the run. In this condition, probe trials showed that gerbils used retinal image size to compute target distance. Collectively, the results showed that gerbils were able to rapidly and flexibly utilize available information to complete a visually guided running task. The results are discussed in the context of the psychophysics of cue combination and its neural underpinnings.

Functional polycystin-1 expression is developmentally regulated during epithelial morphogenesis in vitro: downregulation and loss of membrane localization during cystogenesis.

Polycystin-1 is a protein mutated in the majority of cases of autosomal dominant polycystic kidney disease (ADPKD), but its role in the molecular pathway of tubulogenesis and cystogenesis is not understood. To define the role of polycystin-1 during dynamic changes in formation of intercellular contacts and cell polarity accompanying epithelial morphogenesis, we have utilized a 3D MDCK in vitro model of tubulogenesis and cystogenesis. Here we demonstrate that polycystin-1 is a novel component of desmosomal junctions of epithelial cells. A striking downregulation of polycystin-1 mRNA was detected in cysts as compared to tubules, leading to altered protein expression and localization. While polycystin-1 is localized to basolateral membranes of MDCK tubules, it is only detected in cytoplasmic pools in cystic cells. Furthermore, the expression of polycystin-1 is modulated during distinct stages of HGF-induced tubulogenesis from MDCK cysts. Thus, polycystin-1 is not detected in intercellular contacts at early steps of tubulogenesis, but assumes its basolateral localization at the time of cell polarization and lumen formation. An important role of polycystin-1 is further demonstrated using the pancreatic ductal epithelial cell line SU.86.86 which undergoes in vitro differentiation resulting in the formation of domes. Dome formation is thought to parallel tubular differentiation and morphogenesis in vivo. Our data reveal significant upregulation of polycystin-1 mRNA and protein levels in domes. Collectively, our results demonstrate a critical importance of controlled level of polycystin-1 expression for proper tubular differentiation and maturation. We suggest that the loss of polycystin-1 from its basolateral location in tubular epithelium may alter critical pathways controlling normal tubulogenesis leading to cystic transformation.