A Natural Language Processing Based Internet Agent

Searching for useful information is a difficult job by the virtue of the information overloading problem. With technological advances, notably the World-Wide Web (WWW), it allows every ordinary information owner to offer information online for others to access and retrieve. However, it also makes up a global information system that is extremely large-scale, diverse and dynamic. Internet agents and Internet search engines have been used to deal with such problems. But the search results are usually not quite relevant to what a user wants since most of them use simple keyword matching. In this paper, we propose a natural language processing based agent (NIAGENT) that understands a user's natural query. NIAGENT not only cooperates with a meta Internet search engine in order to increase recall of web pages but also analyzes the contents of the referenced documents to increase precision. Moreover, the proposed agent is autonomous, light-weight, and multithreaded. The architectural design also represents an interesting application of a distributed and cooperative computing paradigm. A prototype of NIAGENT, implemented in Java, shows its promise to find more useful information than keyword based searching.published_or_final_versio

A Soil Model Considering Principal Stress Rotations

This paper presents an elastoplastic soil model considering the principal stress rotation (PSR). The model is developed on the basis of a well-established kinematic hardening soil model using the bounding surface concept. The significance of including the PSR in soil models is presented through comparing the predictions using the new and original models. The model can consider the PSRs under multiple directions, and features relatively simple formulations and easy numerical implementations. Model predictions are compared with different experimental results and verified. Simulations of multiple dimensional PSRs are also studied

A RAMP marker linked to the tobacco black shank resistant gene

Bulk segregant analysis (BSA) and randomly amplified microsatellite polymorphism (RAMP) were employed to analyze F2 individuals of the Yunyan 317×Hubei 517 to screen and characterize molecularmarkers linked to black shank resistant gene. A total of 800 arbitrary decamer oligonucleotide primerpairs were used for RAMP analysis. Primer pair GT (CA) 4/S89, producing one RAMP marker GT (CA)4/S89550, was tightly linked to the black shank resistant gene. Results of Southern blot suggest that the fragment GT (CA) 4/S89550 was existed in Yunyan 317 and resistant plants, and absent in Hubei 517.Linkage analysis was carried out using marker GT (CA) 4/S89550 on 752 black shank high-resistant individuals of F2 progenies from crossing between Yunyan 317 and Hubei 517. Our results indicated thatthe genetic distances between GT (CA) 4/S89550 and black shank resistant gene was 1.4cM

Genetic diversity among natural populations of Ottelia acuminata (Gaghep.) Dandy revealed by ISSR

Ottelia acuminata (Gagnep.) Dandy, an aquatic species of the Hydrocharitaceae, is endemic to China. A performance comparison of genetic diversity of 4 natural populations was conducted to investigatewhether or not water pollution in their habitats has anything to do with this species being endangered. A total number of 120 O. acuminate accessions were analyzed, by amplification of their DNAs with 15 primers (ISSR). Thirteen primers were scored and 214 bands were detected, of which 170 werepolymorphic (79.44%). The results showed that the genetic indices in polluted Jian Lake group were always the smallest ones, when compared with those of the other groups. It indicated that the polluted water did affect the genetic diversity of O. acuminate populations. And ISSRs seemed to be effectivetools for detecting genetic variation among O. acuminate geographical groups

Intelligent spider for Internet searching

As World Wide Web (WWW) based Internet services become more popular, information overload also becomes a pressing research problem. Difficulties with searching on the Internet get worse as the amount of information that is available increases. A scalable approach to support Internet search is critical to the success of Internet services and other current or future national information infrastructure (NII) applications. A new approach to build an intelligent personal spider (agent), which is based on automatic textual analysis of Internet documents, is proposed. Best first search and genetic algorithm have been tested to develop the intelligent spider. These personal spiders are able to dynamically and intelligently analyze the contents of the users' selected homepages as the starting point to search for the most relevant homepages based on the links and indexing. An intelligent spider must have the capability to make adjustments according to progress of searching in order to be an intelligent agent. However, the current searching engines do not have communication between the users and the robots. The spider presented in the paper uses Java to develop the user interface such that the users can adjust the control parameters according to the progress and observe the intermediate results. The performances of the genetic algorithm based and best first search based spiders are also reported.published_or_final_versio

Isolation and Characterization of Batatasin III and 3,4’- Dihydroxy-5-methoxybibenzyl: A Pair of Positional Isomers from Sunipia scariosa

Purpose: To isolate and characterize chemical compounds of biological importance from the whole plant of Sunipia scariosa.Methods: The whole plant of Sunipia scariosa was extracted with methanol (MeOH) and chromatographed on silica gel and sephadex LH-20 to afford the pure isolates. High perfomance liquild chromatography (HPLC) was used for further purification of the isolated compounds. Characterization ofthe isolated compounds was achieved by 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS).Results: Batatasin III (3,3’-dihydroxy-5-methoxybibenzyl) and  3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers, were isolated from the whole plant of Sunipia scariosa. The yields of the two isomers were 60 and 40 %, respectively, from the mixture of two  compounds.Conclusion: Batatasin III and 3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers were successfully isolated from the whole plant of Sunipia scariosa for the first time.Keywords: Sunipia scariosa, Batatasin III, 3,4’-Dihydroxy-5-methoxybibenzyl, Isomer

The effect of Ga-doped nanocrystalline ZnO electrode on deep-ultraviolet enhanced GaN photodetector

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Aqcostic quantification and colour kinesis: evaluation of left atrial and left ventricular function in real time

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First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

Aim: Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage. Though it has been succeeded in many centers worldwide, the safety of the donor is still a major concern, especially in donors with anatomy variation. We succeeded in performing the first two cases of living related liver transplantation with complicated anatomy of blood vessels as a way to overcome cadaveric organ shortage in Beijing. Methods: Two patients, with congenital liver fibrosis and congenital biliary atresia were performed with living donor liver transplantation in our hospital and then followed up from November 12 to December 13, 2001. The two living donors, mother and father, were healthy aged 34 and 35 years. One right lobe (segment V, VI, VII, VIII) and one left lateral lobe (segment II and III) were used. The grafts weighed 394 g and 300 g. The ratio of graff weight to the standard liver volume (SLV) of donors was 68% and 27%. The graft weight to recipient body weight ratio was 3.2% and 4.4%. The graft weight to recipient estimated standard liver mass (ESLM) ratio was 63% and 85%. The two donors had complicated blood vessel variation. Results: Two patients undergone living donor liver transplantation had good results. Abnormal liver function with high bilirubin level appeared in a few days after operation, bur liver function returned to normal one month after operation with bilirubin level almost decreased to near normal. No bleeding, thrombosis, infection and bile leakage occurred. One had an acure rejection and recovered. The two donors recovered in two weeks. One had slight fever because of a little collection in abdomen and recovered after paracentesis and drainage. Conclusion: Living donor liver transplantation has been proved to be a good way that offers a unique opportunity of getting a timely liver graft as a response to shortage of pediatric donors, though it could be a technically difficult operation if there is anatomical variation. Copyright © 2004 by The WJG Press.published_or_final_versio

Individually Frequency Tunable Dual- and Triple-band Filters in a Single Cavity

© 2013 IEEE. This paper presents a new class of second-order individually and continuously tunable dual- and triple-band bandpass filters in a single metal cavity. Each passband is realized by two identical metal posts. These dual- and triple-band tunable filters are achieved by putting two or three identical sets of metal-post pair in a single metal cavity. Metal screws are co-designed as a part of the metal posts to control their insertion depth inside the cavity. In this way, the resonant frequencies can be continuously controlled and designed at the desired frequency bands. Moreover, the distance between the two metal posts in a post pair can be freely tuned. Thus, the external quality factor (Qe) and coupling coefficient (k) between the adjacent modes can be easily adjusted to meet the specified requirement in synthesis design. At the bottom of the cavity, some grooves are used to extend the tunable frequency range and make the resonant frequency linearly varied with the height of the metal post. The center frequency of each passband can be independently tuned with a frequency range of 0.8-3.2 GHz and tunable ratio of 4. Finally, the continuously tunable dual- and triple-band bandpass filters prototypes with second order response are designed and fabricated, of which each passband can be individually tuned with a large tuning range