三种概念学习形式的逻辑定义与归约

介绍了３种主要的概念学习形式———解释学习、断定学习（部分解释学习）和满足学习，讨论了这３种概念学习形式的归约关系．

Research on fault location technology based on BP neural network in DWDM optical network

BP neural network is introduced to the fault location field of DWDM optical network in this paper. The alarm characteris-tics of the optical network equipments are discussed,and alarm vector and fault vector diagrams are generated by analyzing some typical instances. A 17×14×18 BP neural network structure is constructed and trained by using MATLAB. By comparing the training performances,the best training algorithm of fault location among the three training algorithms is chosen. Numerical simulation results indicate that the sum squared error (SSE) of fault location is less than 0.01,and the processing time is less than 100 ms. This method not only well deals with the missing alarms or false alarms,but also improves the fault location accuracy and real-time ability.

Identification of the layered morphology of the esophageal wall by optical coherence tomography

AIM： To assess each layer of the optical coherence tomography （OCT） image of the esophageal wall with reference to the histological structure, METHODS： Resected specimens of fresh pig esophagus was used as a model for the esophageal wall. We injected cyanoacrylate adhesive into the specimens to create a marker, and scanned them using a miniature OCT probe. The localization of these markers was assessed in the OCT images. Then we compared the OCT-imaged morphology with the corresponding histological section, guided by the cyanoacrylate adhesive markers. We prepared a second set of experiments using nylon sutures as markers. RESULTS： The OCT image of the esophageal specimen has a clear five-layered morphology. First, it consisted of a relatively less reflective layer; second, a more reflective layer; third, a less reflective layer; fourth, a more reflective layer; and fifth, a less reflective layer. Comparing the OCT images with marked histological sections showed that the first layer corresponded to stratified squamous epithelium; the second to lamina propria; the third to muscularis mucosa; fourth, submucosa; and fifth, muscularis propria with deeper structures of the esophageal wa CONCLUSION： We demonstrated that the OCT image of the normal esophageal wall showed a five- layered morphology, which corresponds to histological esophageal wall components.

SYSTEMATIC ERROR FROM Th/U RATIO IN LUMINESCENCE AND ESR DATING

In luminescence and ESR dating methods,total count rate from thick source alpha counting is commonly used fox estimating annual dose with assumption of equal activities for both uranium and thorium decay chains.This is equal to a Th/U weight ratio of 3.2.The systematic error in total dose rate due to uncertainty of the ratio is calculated.It is found that the error is insignificant for uniformly distributed samples such as sediment,but can be significant for some extreme circumstances.

A stable image reconstruction algorithm for ECT

Most image reconstruction algorithms developed for electrical capacitance tomography (ECT) can only reconstruct qualitative images. Stabled quantitative image reconstruction is necessary for many applications. To get stable ECT image, the authors constructed a compressive operator and developed a new iterative algorithm, which can overcome the semi-convergence occurring in the Landweber iteration reconstruction technique. Experimental results showed that the stability and quality of re- constructed images are improved significantly.

THICKNESS RESPONSE OF β DOSE-RATE IN TL DATING OF POTTERY FRAGMENTS

Generally, the walls of ceramic ware are thin and the sample to be used for TL dating has to be collected from 1￣2mm under the surface.This call introduce significant error into the dating method.Therefore,the results of a series of simulated experiments are reported on the build-up effect of the internal β dose response in different thicknesses of pottery fragments (involving tile and brick).Correction factors,corresponding to different thicknesses,and correction 'depths' are proposed in terms of the experimental findings which may be incorporatd into the dating methods.

The Dynamic Characteristics of Strain Fields and Crustal Movement before the Wenchuan Earthquake (M_S=8.0)

In this paper, we analyze the crustal movements, strain field changes and large scale dynamic characteristics of horizontal deformation before the Wenchuan earthquake （ Ms = 8.0） using GPS data obtained from the Crustal Movement Observation Network of China. The following issues are discussed. First, the strain fields of the Longmeushan fault zone located at the epicenter show slow accumulation, because of the tectonic dynamics process subjected to the eastward movement of the Bayan Har block. Second, the different movements between the Longmenshan fault and South China block are smaller than the errors of GPS observation. Third, the high value of compressive strain （2004 - 2007） is located at the epicenter, which shows that the local squeezing action is stronger than before. Fourth, the data from GPS reference stations in the Chinese Mainland show that crustal shortening is faster than before in the north-eastern direction, which is part of the background of the local tectonic dynamics increase in the Longmenshan fault zone.

The Evolution of Stinging Hairs and Other Characters in Nettle Family

Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters（e.g.flower,achene.stipule,bract）require a microscope for accurate determination.Meanwhile,most Uriiceae species have stinging hairs which make them more difficult to collect and identify.As a result,the infra-familial classification of Urticaceae has been controversial for more than a century.A research group led by Prof.

Helicobacter pylori antigen and its IgG, IgA -type specific immunocomplexes in sera from patients with Helicobacter pylori infection

OBJECTIVE: To explore the characteristics of Helicobacter pylori (H. pylori) antigen in serum and to evaluate its clinical diagnostic value. METHODS: Enzyme-linked immunosorbant assay (ELISA) was developed to detect the soluble H. pylori antigen (S-Hp) and circulatory specific H. pylori antigen immunocomplexes (Hp-IC) in serum. RESULTS: The positive rate of S-Hp was 90.91% from 66 patients with H. pylori infection, which was much greater than 0% found in 28 controls (P

Three-dimensional in situ stress determination by anelastic strain recovery and its application at the Wenchuan Earthquake Fault Scientific Drilling Hole-1(WFSD-1)

In situ stress state becomes more and more significant with in-depth research on geodynamics and energy development.However,there has not been an economic and effective method developed to determine deep three-dimensional in situ stress.The Anelastic Strain Recovery(ASR)method is a newly developed technique that can determine three-dimensional in situ stresses.After the 12 May 2008 Ms8.0 Wenchuan earthquake,the ASR method was used for the first time in China's Mainland to measure the in situ stresses in the WFSD scientific boreholes in Sichuan Province,China.In this paper,the basic procedure of the ASR method is introduced in detail and the compliances of ASR for boring cores are investigated.The results show that the maximum principal stress direction was NW64°at a measured depth(MD)of 1173 m(vertical depth 1151 m)in WFSD-1.The ratio of shear mode to the volume mode compliance of ASR was 2.9.And the three principal stresses at 1173 m MD in WFSD-1are 43,28 and 25 MPa.Combined with stress measurement results determined using other in situ measurement methods along the Longmenshan fault zone,the directions of the maximum horizontal principal stress changes from E-W to NEE-SWW to NWW-SEE when moving from NE to SW along the Longmenshan fault zone.This change is in agreement with the stress regime of the Longmenshan fault zone of the Wenchuan Earthquake,which supports a stress regime consisting predominantly of thrusts in the southwest and strike-slip in the northeast.

Accuracy and outcome of rapid ultrasound in shock and hypotension （RUSH） in Egyptian polytrauma patients

Purpose： ＂Polytrauma＂ patients are of a higher risk of complications and death than the summation of expected mortality and morbidity of their individual injuries. The ideal goal in trauma resuscitation care is to identify and treat all injuries. With clinical and technological advanced imaging available for diagnosis and treatment of traumatic patients, point of care-rapid ultrasound in shock and hypotension （RUSH） significantly affects modern trauma services and patient outcomes. This study aims to evaluate the accuracy of RUSH and patient outcomes by early detection of the causes of unstable polytrauma. Methods： This cross-sectional, prospective study included 100 unstable polytrauma patients admitted in Suez Canal University Hospital. Clinical exam, RUSH and pan-computed tomography （pan-CT） were conducted. The result of CT was taken as the standard. Patients were managed according to the advanced trauma life support （ATLS） guidelines and treated of life threatening conditions if present. Patients were followed up for 28 days for a short outcome. Results： The most diagnostic causes of unstability in polytrauma patients by RUSH are hypovolemic shock （64%）, followed by obstructive shock （14%）, distributive shock （12%） and cardiogenic shock （10%） respectively. RUSH had 94.2% sensitivity in the diagnosis of unstable polytrauma patients; the accuracy of RUSH in shock patients was 95.2%. Conclusion： RUSH is accurate in the diagnosis of unstable polytrauma patients; and 4% of patients were diagnosed during follow-up after admission by RUSH and pan-CT.

Quantitative analysis of nanoscale deformation fields of a crack-tip in single-crystal silicon

A mode II crack in single-crystal silicon was investigated experimentally using high-resolution transmission electron microscopy.Geometric phase analysis and numerical moiré method were employed to map the deformation fields of the crack-tip area.The normal strain field maps of the crack-tip area indeed showed the deformation occurs primarily in the vicinity of the dislocations and the normal strains are near zero in the crack-tip area.The shear strain field map shows that the relatively large shear strain is in the crack-tip area.The experimental results were compared with the predictions of linear elastic fracture mechanics.The comparison shows that measured strain distribution ahead of the crack-tip agrees with the predictions of linear elastic fracture mechanics up to 1 nm from the crack-tip.