Airborne area-array whisk-broom imaging systems typically adopt constant-speed scanning schemes.For large-inertia scanning systems,constant-speed scanning requires substantial time to complete the reversal motion,redu...Airborne area-array whisk-broom imaging systems typically adopt constant-speed scanning schemes.For large-inertia scanning systems,constant-speed scanning requires substantial time to complete the reversal motion,reducing the system's adaptability to high-speed reversal scanning and decreasing scanning efficiency.This study proposes a novel sinusoidal variable-speed roll scanning strategy,which reduces abrupt changes in speed and acceleration,minimizing time loss during reversals.Based on the forward image motion compensation strategy in the pitch direction,we establish a line-of-sight(LOS)position calculation model with vertical flight path correction(VFPC),ensuring that the central LOS of the scanned image remains stable on the same horizontal line,facilitating accurate image stitching in whisk-broom imaging.Through theoretical analysis and simulation experiments,the proposed method improves the scanning efficiency by approximately 18.6%at a 90o whiskbroom imaging angle under the same speed height ratio conditions.The new VFPC method enables wide-field,high-resolution imaging,achieving single-line LOS horizontal stability with an accuracy of better than O.4 mrad.The research is of great significance to promote the further development of airborne area-array whisk-broom imaging technology toward wider fields of view,higher speed height ratios,and greater scanning efficiency.展开更多
BACKGROUND Rectal cancer is a common malignant tumor of the digestive system,with older patients representing the predominantly affected population.Magnetic resonance imaging(MRI)has been widely applied in preoperativ...BACKGROUND Rectal cancer is a common malignant tumor of the digestive system,with older patients representing the predominantly affected population.Magnetic resonance imaging(MRI)has been widely applied in preoperative tumor assessment;however,the value of high-resolution MRI(HR-MRI)combined with dynamic contrast-enhanced(DCE)scanning in the preoperative diagnosis of rectal cancer in older patients remains unclear.AIM To evaluate the value of HR-MRI combined with DCE scanning in the preoperative diagnosis of rectal cancer in older patients.METHODS This retrospective study included 148 consecutive older female patients with rectal cancer who were treated at our hospital between December 2020 and December 2024.Clinical data and HR-MRI and DCE scan findings were collected.Histopathological examination after surgical resection served as the gold standard.The diagnostic accuracy of MRI for preoperative T and N staging was calculated.Consistency,sensitivity,and specificity between HR-MRI combined with DCE scanning and pathological staging were analyzed using the k test.Among the 148 patients,the overall accuracy of T staging was 84.5%.Sensitivity for T1,T2,T3,and T4 staging was 75.00%,62.50%,89.47%,and 90.48%,respectively,whereas specificity was 100.00%,94.35%,79.25%,and 96.06%,respectively.T staging based on HR-MRI combined with DCE scanning showed good agreement with pathological staging(k=0.8176,P<0.001).For N staging,sensitivity and specificity were 54.88%and 84.85%for N0,36.96%and 72.55%for N1,and 70.00%and 73.44%for N2,respectively;agreement with pathological N staging was poor(k=0.259,P<0.001).CONCLUSION HR-MRI combined with DCE scanning demonstrates high diagnostic accuracy for T staging of rectal cancer in older patients and can provide a theoretical basis for treatment planning.However,its diagnostic accuracy for N staging requires improvement.展开更多
To restore the sub image in a rosette scanning system and provide target recognition system with a low distorted image, the sub image is processed with morphological filters. Morphological filter can process rosette...To restore the sub image in a rosette scanning system and provide target recognition system with a low distorted image, the sub image is processed with morphological filters. Morphological filter can process rosette scanning sub images more effectively. It can restore the original area and shape of an object effectively, and keep the energy information of the object. To process sub images got by a rosette scanning system, morphological filter is more effective than traditional low pass filter.展开更多
The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation met...The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation methods, a new approach based on the shadow area percentage （SAP） that can be used to quantify surface roughness is proposed in this article. Firstly, by the help of laser scanning technique, the three-dimensional model of the surface of rock discontinuity was established. Secondly, a light source was simulated, and there would be some shadows produced on the model surface. Thirdly, to obtain the value of SAP of each specimen, the shadow detection technique was introduced for use. Fourthly, compared with the result from direct shear testing and based on statistics, an empirical for- mula was found among SAP, normal stress, and shear strength. Data of Yujian （~ River were used as an example, and the following conclusions have been made. （1） In the case of equal normal stress, the peak shear stress is positively proportional to the SAP. （2） The formula for estimating was derived, and the predictions of peak-shear strength made with this equation well agreed with the experimental re- suits obtained in laboratory tests.展开更多
·AIM:Toevaluatethe diagnostic properties of wide-field fundus autofluorescence(FAF) scanning laser ophthalmoscope(SLO) imaging for differentiating choroidal pigmented lesions.·METHODS: A consecutive series o...·AIM:Toevaluatethe diagnostic properties of wide-field fundus autofluorescence(FAF) scanning laser ophthalmoscope(SLO) imaging for differentiating choroidal pigmented lesions.·METHODS: A consecutive series of 139 patients were included, 101 had established choroidal melanoma with13 untreated lesions and 98 treated with radiotherapy.Thirty-eight had choroidal nevi. All patients underwent a full ophthalmological examination, undilated wide-field imaging, FAF and standardized US examination. FAF images and imaging characteristics from SLO were correlated with the structural findings in the two patient groups.·RESULTS: Mean FAF intensity of melanomas was significantly lower than the FAF of choroidal nevi. Only 1out of 38 included eyes with nevi touched the optic disc compared to 31 out of 101 eyes with melanomas. In 18 out of 101 melanomas subretinal fluid was seen at the pigmented lesion compared to none seen in eyes with confirmed choroidal nevi. In 'green laser separation', a trend towards more mixed FAF appearance of melanomas compared to nevi was observed. The mean maximal and minimal transverse and longitudinal diameters of melanomas were significantly higher than those of nevi.·CONCLUSION: Wide-field SLO and FAF imaging may be an appropriate non-invasive diagnostic screening tool to differentiate benign from malign pigmented choroidal lesions.展开更多
AIM To investigate the application of confocallaser scanning microscopy(CLSM)in tumorpathology and three-dimensional( 3-D )reconstruction by CLSM in pathologic specimensof hepatocellular carcinoma(HCC).METHODS The 30...AIM To investigate the application of confocallaser scanning microscopy(CLSM)in tumorpathology and three-dimensional( 3-D )reconstruction by CLSM in pathologic specimensof hepatocellular carcinoma(HCC).METHODS The 30μm thick sections were cutfrom the paraffin-embedded tissues of HCC,hyperplasia and normal liver,stained with DNAfluorescent probe YOYO-1 iodide and examinedby CLSM to collect optical sections of nuclei and3-D images reconstructed.RESULTS HCC displayed chaotic arrangementof carcinoma cell nuclei,marked pleomorphism,indented and irregular nuclear surface,andirregular and coarse chromatin texture.CONCLUSION The serial optical tomograms ofCLSM can be used to create 3-D reconstruction ofcancer cell nuclei.Such 3-D impressions mightbe helpful or even essential in making anaccurate diagnosis.展开更多
An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province. The basic working principles, performance indexes, features and data collection and proce...An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province. The basic working principles, performance indexes, features and data collection and processing methods are illus-trated. The point cloud results are analyzed in detail. The rescale range analysis method was used to analyze the deformation char-acteristics of the slope. The results show that the trend of slope displacement is stable and that the degree of landslide danger is low. This work indicates that 3-D laser image scanning can supply multi-parameter, high precision real time data over long distances. These data can be used to study the distortion of the slope quickly and accurately.展开更多
Cone photoreceptor cell identication is important for the early diagnosis of retinopathy.In this study,an object detection algorithm is used for cone cell identication in confocal adaptive optics scanning laser ophtha...Cone photoreceptor cell identication is important for the early diagnosis of retinopathy.In this study,an object detection algorithm is used for cone cell identication in confocal adaptive optics scanning laser ophthalmoscope(AOSLO)images.An effectiveness evaluation of identication using the proposed method reveals precision,recall,and F_(1)-score of 95.8%,96.5%,and 96.1%,respectively,considering manual identication as the ground truth.Various object detection and identication results from images with different cone photoreceptor cell distributions further demonstrate the performance of the proposed method.Overall,the proposed method can accurately identify cone photoreceptor cells on confocal adaptive optics scanning laser ophthalmoscope images,being comparable to manual identication.展开更多
The activity of horseradish peroxidase at b-cyclodextrin polymer was imaged by scanning electrochemical microscopy using 3, 3', 5, 5'-tetramethylbenzide and H2O2 as the substrates.
A laser scanning confocal imaging-surface plasmon resonance （LSCI-SPR） instrument integrated with a wavelength-dependent surface plasmon resonance （SPR） sensor and a laser scanning confocal microscopy （LSCM） is ...A laser scanning confocal imaging-surface plasmon resonance （LSCI-SPR） instrument integrated with a wavelength-dependent surface plasmon resonance （SPR） sensor and a laser scanning confocal microscopy （LSCM） is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science.展开更多
Photoacoustic imaging is a potential candidate for in vivo brain imaging,whereas,its imaging performance could be degraded by inhomogeneous multi-layered media,consisted of scalp and skull.In this work,we propose a lo...Photoacoustic imaging is a potential candidate for in vivo brain imaging,whereas,its imaging performance could be degraded by inhomogeneous multi-layered media,consisted of scalp and skull.In this work,we propose a low-artifact photoacoustic microscopy(LAPAM)scheme,which combines conventional acoustic-resolution photoacoustic microscopy with scanning acoustic microscopy to suppress the reflection artifacts induced by multi-layers.Based on similar propagation characteristics of photoacoustic signals and ultrasonic echoes,the ultrasonic echoes can be employed as the filters to suppress the reflection artifacts to obtain low-artifact photoacoustic images.Phantom experiment is used to validate the effectiveness of this method.Furthermore,LAPAM is applied for in-vivo imaging mouse brain without removing the scalp and the skull.Experimental results show that the proposed method successfully achieves the low-artifact brain image,which demonstrates the practical applicability of LAPAM.This work might improve the photoacoustic imaging quality in many biomedical applications which involve tissues with complex acoustic properties,such as brain imaging through scalp and skull.展开更多
Adaptive optics scanning laser ophthalmoscopy（AOSLO） has been a promising technique in funds imaging with growing popularity. This review firstly gives a brief history of adaptive optics（AO） and AO-SLO. Then it co...Adaptive optics scanning laser ophthalmoscopy（AOSLO） has been a promising technique in funds imaging with growing popularity. This review firstly gives a brief history of adaptive optics（AO） and AO-SLO. Then it compares AO-SLO with conventional imaging methods（fundus fluorescein angiography, fundus autofluorescence, indocyanine green angiography and optical coherence tomography） and other AO techniques（adaptive optics flood-illumination ophthalmoscopy and adaptive optics optical coherence tomography）. Furthermore, an update of current research situation in AO-SLO is made based on different fundus structures as photoreceptors（cones and rods）, fundus vessels, retinal pigment epithelium layer, retinal nerve fiber layer, ganglion cell layer and lamina cribrosa. Finally, this review indicates possible research directions of AO-SLO in future.展开更多
We study the influence of limited-view scanning on the depth imaging of photoacoustic tomography. The situation, in which absorbers are located at different depths with respect to the limited-view scanning trajectory,...We study the influence of limited-view scanning on the depth imaging of photoacoustic tomography. The situation, in which absorbers are located at different depths with respect to the limited-view scanning trajectory, is called depth imaging and is investigated in this paper. The results show that limited-view scanning causes the reconstructed intensity of deep absorbers to be weaker than that of shallow ones and that deep absorbers will be invisible if the scanning range is too small. The concept of effective scanning angle is proposed to analyse that phenomenon. We find that an effective scanning angle can well predict the relationship between scanning angle and the intensity ratio of absorbers. In addition, limited-view scanning is employed to improve image quality.展开更多
The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning l...The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular resolution.However,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and laborious.Unfortunately,almost half of patients are unable to obtain stitched images because of their poorfixation.To solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger FOV.In the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for sufficiently digitizing light energy.Captured human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular resolutions.Take advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5eccentricity.The AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area.展开更多
This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area rec...This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area reconnaissance of hot regions. First,the working principle and working sequence of the FSM are briefly analyzed. The mathematical model of the FSM system is built by modeling its dynamic and electrical properties, and the rationality of the model is validated by means of model identification. Second,the influence of external sources of disturbance such as the carrier and moment on the control precision of the FSM is effectively suppressed by the jointly controlling of proportional integral(PI)and disturbance observer(DOB), thus realizing a high precision and strong robustness control of the FSM system. Then, this paper designs an experimental prototype and introduces a special optical structure to enable the infrared camera to share the FSM with the visible light camera. Finally, the influence of the velocity difference between the mirror of the FSM and the rotating platform on the imaging quality of the system is experimentally analyzed by using the image sharpness evaluation method based on point sharpness. A good dynamic scanning and staring imaging result is achieved when the velocity of these two components correspond.展开更多
In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output...In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.展开更多
A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte i...A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte in lager quantity of the captured images if we directly scan the blood smear along an ordinary zigzag scanning routine with high power(100^(x))objective.Due to the larger field of view of low power(10^(x))objective,the captured low power blood smear images can be used to locate leukocytes.All of the located positions make up a specific routine,if we scan the blood smear along this routine with high power objective,there will be definitely leukocytes in almost all of the captured images.Considering the number of captured images is still large and some leukocytes may be redundantly captured twice or more,a leukocyte clustering method based on max-min distance clustering is developed to reduce the total number of captured images as well as the number of redundantly captured leukocytes.This method can improve the scanning eficiency obviously.The experimental results show that the proposed method can shorten scanning time from 8.0-14.0min to 2.54.0 min while extracting 110 nonredundant individual high power leukocyte images.展开更多
The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are revi...The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions.展开更多
There should be high resolution demand that is better than 1000 DPI(dot per inch) for high precision image scanning system. This paper introduced the two-level computer controlled system that consisted of LS-3500 film...There should be high resolution demand that is better than 1000 DPI(dot per inch) for high precision image scanning system. This paper introduced the two-level computer controlled system that consisted of LS-3500 film scanner, AST386/33 monitoring control level and Intel 8031 single chip computer that is used as DDC level. The formula for scanning image data processing and methods of statistic parameters calculating are described.展开更多
The microwave-induced thermoacoustic imaging(TAI)technology has both the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging(UI),so it has carried out exploratory application res...The microwave-induced thermoacoustic imaging(TAI)technology has both the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging(UI),so it has carried out exploratory application research in various areas,such as the early detection of breast tumors and cerebrovascular diseases.However,the microwave generator used in the traditional TAI technology is huge and expensive,and the temporal resolution is also too low due to the single-element scanning mechanism.Thus,it is difficult to meet the needs of clinical applications.In this paper,the iterative process and the analysis of related application scenarios from single-element scanning to portable and array-based TAI,such as the miniaturized microwave generator,handheld antenna,multi-channel data acquisition,and UI/TAIdual-modality imaging,are reviewed,and the future trends of this technology are discussed.This review helps researchers in the field of TAI learn the technological development process and future trends.It also deepens clinicians’understanding of TAI so as to put forward more application requirements.展开更多
基金Supported by the National Key Research and Development Program(2023YFC3107602)。
文摘Airborne area-array whisk-broom imaging systems typically adopt constant-speed scanning schemes.For large-inertia scanning systems,constant-speed scanning requires substantial time to complete the reversal motion,reducing the system's adaptability to high-speed reversal scanning and decreasing scanning efficiency.This study proposes a novel sinusoidal variable-speed roll scanning strategy,which reduces abrupt changes in speed and acceleration,minimizing time loss during reversals.Based on the forward image motion compensation strategy in the pitch direction,we establish a line-of-sight(LOS)position calculation model with vertical flight path correction(VFPC),ensuring that the central LOS of the scanned image remains stable on the same horizontal line,facilitating accurate image stitching in whisk-broom imaging.Through theoretical analysis and simulation experiments,the proposed method improves the scanning efficiency by approximately 18.6%at a 90o whiskbroom imaging angle under the same speed height ratio conditions.The new VFPC method enables wide-field,high-resolution imaging,achieving single-line LOS horizontal stability with an accuracy of better than O.4 mrad.The research is of great significance to promote the further development of airborne area-array whisk-broom imaging technology toward wider fields of view,higher speed height ratios,and greater scanning efficiency.
基金Supported by Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-3-012B.
文摘BACKGROUND Rectal cancer is a common malignant tumor of the digestive system,with older patients representing the predominantly affected population.Magnetic resonance imaging(MRI)has been widely applied in preoperative tumor assessment;however,the value of high-resolution MRI(HR-MRI)combined with dynamic contrast-enhanced(DCE)scanning in the preoperative diagnosis of rectal cancer in older patients remains unclear.AIM To evaluate the value of HR-MRI combined with DCE scanning in the preoperative diagnosis of rectal cancer in older patients.METHODS This retrospective study included 148 consecutive older female patients with rectal cancer who were treated at our hospital between December 2020 and December 2024.Clinical data and HR-MRI and DCE scan findings were collected.Histopathological examination after surgical resection served as the gold standard.The diagnostic accuracy of MRI for preoperative T and N staging was calculated.Consistency,sensitivity,and specificity between HR-MRI combined with DCE scanning and pathological staging were analyzed using the k test.Among the 148 patients,the overall accuracy of T staging was 84.5%.Sensitivity for T1,T2,T3,and T4 staging was 75.00%,62.50%,89.47%,and 90.48%,respectively,whereas specificity was 100.00%,94.35%,79.25%,and 96.06%,respectively.T staging based on HR-MRI combined with DCE scanning showed good agreement with pathological staging(k=0.8176,P<0.001).For N staging,sensitivity and specificity were 54.88%and 84.85%for N0,36.96%and 72.55%for N1,and 70.00%and 73.44%for N2,respectively;agreement with pathological N staging was poor(k=0.259,P<0.001).CONCLUSION HR-MRI combined with DCE scanning demonstrates high diagnostic accuracy for T staging of rectal cancer in older patients and can provide a theoretical basis for treatment planning.However,its diagnostic accuracy for N staging requires improvement.
文摘To restore the sub image in a rosette scanning system and provide target recognition system with a low distorted image, the sub image is processed with morphological filters. Morphological filter can process rosette scanning sub images more effectively. It can restore the original area and shape of an object effectively, and keep the energy information of the object. To process sub images got by a rosette scanning system, morphological filter is more effective than traditional low pass filter.
基金supported by the China Geological Survey (No.1212011014030)the Major State Basic Research Development Program of China (973 Program) (No.2011CB710600)
文摘The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation methods, a new approach based on the shadow area percentage （SAP） that can be used to quantify surface roughness is proposed in this article. Firstly, by the help of laser scanning technique, the three-dimensional model of the surface of rock discontinuity was established. Secondly, a light source was simulated, and there would be some shadows produced on the model surface. Thirdly, to obtain the value of SAP of each specimen, the shadow detection technique was introduced for use. Fourthly, compared with the result from direct shear testing and based on statistics, an empirical for- mula was found among SAP, normal stress, and shear strength. Data of Yujian （~ River were used as an example, and the following conclusions have been made. （1） In the case of equal normal stress, the peak shear stress is positively proportional to the SAP. （2） The formula for estimating was derived, and the predictions of peak-shear strength made with this equation well agreed with the experimental re- suits obtained in laboratory tests.
文摘·AIM:Toevaluatethe diagnostic properties of wide-field fundus autofluorescence(FAF) scanning laser ophthalmoscope(SLO) imaging for differentiating choroidal pigmented lesions.·METHODS: A consecutive series of 139 patients were included, 101 had established choroidal melanoma with13 untreated lesions and 98 treated with radiotherapy.Thirty-eight had choroidal nevi. All patients underwent a full ophthalmological examination, undilated wide-field imaging, FAF and standardized US examination. FAF images and imaging characteristics from SLO were correlated with the structural findings in the two patient groups.·RESULTS: Mean FAF intensity of melanomas was significantly lower than the FAF of choroidal nevi. Only 1out of 38 included eyes with nevi touched the optic disc compared to 31 out of 101 eyes with melanomas. In 18 out of 101 melanomas subretinal fluid was seen at the pigmented lesion compared to none seen in eyes with confirmed choroidal nevi. In 'green laser separation', a trend towards more mixed FAF appearance of melanomas compared to nevi was observed. The mean maximal and minimal transverse and longitudinal diameters of melanomas were significantly higher than those of nevi.·CONCLUSION: Wide-field SLO and FAF imaging may be an appropriate non-invasive diagnostic screening tool to differentiate benign from malign pigmented choroidal lesions.
文摘AIM To investigate the application of confocallaser scanning microscopy(CLSM)in tumorpathology and three-dimensional( 3-D )reconstruction by CLSM in pathologic specimensof hepatocellular carcinoma(HCC).METHODS The 30μm thick sections were cutfrom the paraffin-embedded tissues of HCC,hyperplasia and normal liver,stained with DNAfluorescent probe YOYO-1 iodide and examinedby CLSM to collect optical sections of nuclei and3-D images reconstructed.RESULTS HCC displayed chaotic arrangementof carcinoma cell nuclei,marked pleomorphism,indented and irregular nuclear surface,andirregular and coarse chromatin texture.CONCLUSION The serial optical tomograms ofCLSM can be used to create 3-D reconstruction ofcancer cell nuclei.Such 3-D impressions mightbe helpful or even essential in making anaccurate diagnosis.
基金supported by the National "Eleventh Five-Year" Forestry Support Program of China (No2006BAD03A1603)
文摘An ILRIS-36D 3-D laser image scanning system was used to monitor the Anjialing strip mine slope on Pingshuo in Shanxi province. The basic working principles, performance indexes, features and data collection and processing methods are illus-trated. The point cloud results are analyzed in detail. The rescale range analysis method was used to analyze the deformation char-acteristics of the slope. The results show that the trend of slope displacement is stable and that the degree of landslide danger is low. This work indicates that 3-D laser image scanning can supply multi-parameter, high precision real time data over long distances. These data can be used to study the distortion of the slope quickly and accurately.
基金the Natural Science Foundation of Jiangsu Province(BK20200214)National Key R&D Program of China(2017YFB0403701)+5 种基金Jiangsu Province Key R&D Program(BE2019682 and BE2018667)National Natural Science Foundation of China(61605210,61675226,and 62075235)Youth Innovation Promotion Association of Chinese Academy of Sciences(2019320)Frontier Science Research Project of the Chinese Academy of Sciences(QYZDB-SSW-JSC03)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB02060000)and Entrepreneurship and Innova-tion Talents in Jiangsu Province(Innovation of Scienti¯c Research Institutes).
文摘Cone photoreceptor cell identication is important for the early diagnosis of retinopathy.In this study,an object detection algorithm is used for cone cell identication in confocal adaptive optics scanning laser ophthalmoscope(AOSLO)images.An effectiveness evaluation of identication using the proposed method reveals precision,recall,and F_(1)-score of 95.8%,96.5%,and 96.1%,respectively,considering manual identication as the ground truth.Various object detection and identication results from images with different cone photoreceptor cell distributions further demonstrate the performance of the proposed method.Overall,the proposed method can accurately identify cone photoreceptor cells on confocal adaptive optics scanning laser ophthalmoscope images,being comparable to manual identication.
文摘The activity of horseradish peroxidase at b-cyclodextrin polymer was imaged by scanning electrochemical microscopy using 3, 3', 5, 5'-tetramethylbenzide and H2O2 as the substrates.
基金supported by the Instrument Developing Project of the Chinese Academy of Sciences (Grant No.YZ200740)the National Natural Science Foundation of China (Grant Nos.60978034 and 10974019)the National High Technology Research and Development Program of China (Grant No.2009AA03Z318)
文摘A laser scanning confocal imaging-surface plasmon resonance （LSCI-SPR） instrument integrated with a wavelength-dependent surface plasmon resonance （SPR） sensor and a laser scanning confocal microscopy （LSCM） is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12027808,11874217,11834008,81900875,and 81770973)Natural Science Foundation of Jiangsu Province,China(Grant No.BK 20181077)。
文摘Photoacoustic imaging is a potential candidate for in vivo brain imaging,whereas,its imaging performance could be degraded by inhomogeneous multi-layered media,consisted of scalp and skull.In this work,we propose a low-artifact photoacoustic microscopy(LAPAM)scheme,which combines conventional acoustic-resolution photoacoustic microscopy with scanning acoustic microscopy to suppress the reflection artifacts induced by multi-layers.Based on similar propagation characteristics of photoacoustic signals and ultrasonic echoes,the ultrasonic echoes can be employed as the filters to suppress the reflection artifacts to obtain low-artifact photoacoustic images.Phantom experiment is used to validate the effectiveness of this method.Furthermore,LAPAM is applied for in-vivo imaging mouse brain without removing the scalp and the skull.Experimental results show that the proposed method successfully achieves the low-artifact brain image,which demonstrates the practical applicability of LAPAM.This work might improve the photoacoustic imaging quality in many biomedical applications which involve tissues with complex acoustic properties,such as brain imaging through scalp and skull.
基金Supported by National Key Scientific Instrument and Equipment Development Project of China (No.2012YQ12008005)
文摘Adaptive optics scanning laser ophthalmoscopy（AOSLO） has been a promising technique in funds imaging with growing popularity. This review firstly gives a brief history of adaptive optics（AO） and AO-SLO. Then it compares AO-SLO with conventional imaging methods（fundus fluorescein angiography, fundus autofluorescence, indocyanine green angiography and optical coherence tomography） and other AO techniques（adaptive optics flood-illumination ophthalmoscopy and adaptive optics optical coherence tomography）. Furthermore, an update of current research situation in AO-SLO is made based on different fundus structures as photoreceptors（cones and rods）, fundus vessels, retinal pigment epithelium layer, retinal nerve fiber layer, ganglion cell layer and lamina cribrosa. Finally, this review indicates possible research directions of AO-SLO in future.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB921504)the National Natural Science Foundation of China(Grant Nos.10874088,10904069,and 11028408)the Natural Science Foundation of Jiangsu Province,China(Grant No.SBK201021985)
文摘We study the influence of limited-view scanning on the depth imaging of photoacoustic tomography. The situation, in which absorbers are located at different depths with respect to the limited-view scanning trajectory, is called depth imaging and is investigated in this paper. The results show that limited-view scanning causes the reconstructed intensity of deep absorbers to be weaker than that of shallow ones and that deep absorbers will be invisible if the scanning range is too small. The concept of effective scanning angle is proposed to analyse that phenomenon. We find that an effective scanning angle can well predict the relationship between scanning angle and the intensity ratio of absorbers. In addition, limited-view scanning is employed to improve image quality.
基金supported by the National Natural Science Foundation of China under Grant No.62075235,National Key R&D Program of China under Grant No.2021YFF0700700Gusu Innovation and Entrepreneurship Leading Talents in Suzhou City under Grant No.ZXL2021425+1 种基金Youth Innovation Promotion Association of the Chinese Academy of Sciences under Grant No.2019320Innovation of Scientific Research Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No.XDA15021304.
文摘The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular resolution.However,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and laborious.Unfortunately,almost half of patients are unable to obtain stitched images because of their poorfixation.To solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger FOV.In the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for sufficiently digitizing light energy.Captured human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular resolutions.Take advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5eccentricity.The AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area.
基金supported by the National Defense Pre-research Project of China during the 12th Five-year Plan Period(4040570201)Innovation Project of Military Academy(ZYX14060014)
文摘This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area reconnaissance of hot regions. First,the working principle and working sequence of the FSM are briefly analyzed. The mathematical model of the FSM system is built by modeling its dynamic and electrical properties, and the rationality of the model is validated by means of model identification. Second,the influence of external sources of disturbance such as the carrier and moment on the control precision of the FSM is effectively suppressed by the jointly controlling of proportional integral(PI)and disturbance observer(DOB), thus realizing a high precision and strong robustness control of the FSM system. Then, this paper designs an experimental prototype and introduces a special optical structure to enable the infrared camera to share the FSM with the visible light camera. Finally, the influence of the velocity difference between the mirror of the FSM and the rotating platform on the imaging quality of the system is experimentally analyzed by using the image sharpness evaluation method based on point sharpness. A good dynamic scanning and staring imaging result is achieved when the velocity of these two components correspond.
文摘In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.
基金supported by the 863 National Plan Foundation of China under Grant No.2007AA01Z333 and Special Grand National Project of China under Grant No.2009ZX02204-008.
文摘A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte in lager quantity of the captured images if we directly scan the blood smear along an ordinary zigzag scanning routine with high power(100^(x))objective.Due to the larger field of view of low power(10^(x))objective,the captured low power blood smear images can be used to locate leukocytes.All of the located positions make up a specific routine,if we scan the blood smear along this routine with high power objective,there will be definitely leukocytes in almost all of the captured images.Considering the number of captured images is still large and some leukocytes may be redundantly captured twice or more,a leukocyte clustering method based on max-min distance clustering is developed to reduce the total number of captured images as well as the number of redundantly captured leukocytes.This method can improve the scanning eficiency obviously.The experimental results show that the proposed method can shorten scanning time from 8.0-14.0min to 2.54.0 min while extracting 110 nonredundant individual high power leukocyte images.
基金supported by the National Key R&D Program(No.2023YFB3709900)the National Nature Science Foundation of China(No.U22A20171)+2 种基金China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202315)the High Steel Center(HSC)at North China University of TechnologyUniversity of Science and Technology Beijing,China.
文摘The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions.
文摘There should be high resolution demand that is better than 1000 DPI(dot per inch) for high precision image scanning system. This paper introduced the two-level computer controlled system that consisted of LS-3500 film scanner, AST386/33 monitoring control level and Intel 8031 single chip computer that is used as DDC level. The formula for scanning image data processing and methods of statistic parameters calculating are described.
基金supported in part by the National Key Research and Development Program of China under Grant No.2018YFB1801503National Natural Science Foundation of China under Grants No.61931006,No.82071940,No.62101111,No.U20A20212,No.61921002,and No.U1930127+1 种基金Fundamental Research Funds for the Central Universities under Grants No.ZYGX2020ZB011 and No.ZYGX2019J013Medico-Engineering Cooperation Funds from University of Electronic Science and Technology of China under Grants No.ZYGX2021YGLH205 and No.ZYGX2021YGLH216.
文摘The microwave-induced thermoacoustic imaging(TAI)technology has both the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging(UI),so it has carried out exploratory application research in various areas,such as the early detection of breast tumors and cerebrovascular diseases.However,the microwave generator used in the traditional TAI technology is huge and expensive,and the temporal resolution is also too low due to the single-element scanning mechanism.Thus,it is difficult to meet the needs of clinical applications.In this paper,the iterative process and the analysis of related application scenarios from single-element scanning to portable and array-based TAI,such as the miniaturized microwave generator,handheld antenna,multi-channel data acquisition,and UI/TAIdual-modality imaging,are reviewed,and the future trends of this technology are discussed.This review helps researchers in the field of TAI learn the technological development process and future trends.It also deepens clinicians’understanding of TAI so as to put forward more application requirements.
