Continuous Reflection Research Articles

Collective reflective assessment for shared epistemic agency by undergraduates in knowledge building

AbstractWe examined the facilitation of shared epistemic agency through a knowledge‐building (KB) design that included analytics‐supported collective reflective assessment (AsCRA). Forty undergraduate students taking a Liberal Studies course at a university in central China used the promising ideas tool and the knowledge building discourse explorer to self‐analyze the online discourse they had created in Knowledge Forum® (KF), an online discourse environment; 34 students in a comparison section of the same course used KF but did not use the additional tools. Both classes were taught by the same teacher and studied the same inquiry topics. Multifaceted analysis of students' interaction in and the quality of discourse on KF, an educational online platform, indicated that analytics‐supported reflective assessment helped them to develop high‐level shared epistemic agency in the KB process. Qualitative analysis showed that AsCRA helped students to focus on high‐level goals (idea negotiation, synthesis of ideas and rise above thinking) in KB, and to engage in continuous assessment, reflection, and action planning to regulate and improve their discourse. The findings have important implications for the design of technology‐rich environments to support learners, and may help teachers identify the potential uses of such environments to encourage learners to engage in productive collaborative inquiry and develop metacognition and agency.

Separating and imaging diffractions in dip domain on the basis of slope analysis

Fracture-cave reservoirs in carbonate rocks are characterized by a large difference in fracture and cavity size, and a sharp variation in lithology and velocity, thereby resulting in complex diffraction responses. Some small-scale fractures and caves cause weak diffraction energy and would be obscured by the continuous reflection layer in the imaging section, thereby making them difficult to identify. This paper develops a diffraction wave imaging method in the dip domain, which can improve the resolution of small-scale diffractors in the imaging section. Common imaging gathers (CIGs) in the dip domain are extracted by Gaussian beam migration. In accordance with the geometric differences of the diffraction being quasilinear and the reflection being quasiparabolic in the dip-domain CIGs, we use slope analysis technique to filter waves and use Hanning window function to improve the diffraction wave separation level. The diffraction dip-domain CIGs are stacked horizontally to obtain diffraction imaging results. Wavefield separation analysis and numerical modeling results show that the slope analysis method, together with Hanning window filtering, can better suppress noise to obtain the diffraction dip-domain CIGs, thereby improving the clarity of the diffractors in the diffraction imaging section.

A Hybrid Tolerance Design Method for the Active Phased-Array Antenna

With the increase of the working frequency of the array antenna, tolerance design has become increasingly important. The state-of-art tolerance design methods mainly deal with the position tolerance of the discrete elements. However, the geometric errors of the whole array have resulted from two aspects: (1) the position errors of the discrete elements and (2) the form errors of the continuous reflection plate. To optimize the position tolerance and flatness simultaneously, a hybrid tolerance design method is proposed. First, the relation between the performance of the array antenna and hybrid tolerances was determined based on the second order Taylor expansion. Then the expectation and variance of the performance were derived. Finally, the hybrid tolerances were optimized and the performance of the antenna was improved. Simulation results proved the effectiveness and efficiency of the proposed hybrid tolerance design method.

Blind Spots in Public Ethics and Integrity Research: What Public Administration Scholars Can Learn from Aristotle

The discourse on ‘good governance’ is of growing importance in the public integrity and public values literature. However, it is not so simple to discern what ‘good governance’ actually means. This paper delves into the work of the ancient philosopher Aristotle who has influenced a stream of practice theories underlining the significance of virtues (instead of values) and of ‘doing things well’. It specifically explores the relevance of Aristotelian philosophy for public professionals by emphasising the central virtue of practical wisdom (phrónêsis or prudence) that sustains craftsmanship as an action-oriented means to achieving viable results. Public integrity, defined as an overarching virtue of a practical sort, contains strong parallels with this Aristotelian phrónêsis which aims to achieve excellence in professional practices – even to the point of being modest if necessary – and assures continuous reflection on public professionals’ quality of work. In other words: public professionals must be persons of integrity – of moral wholeness and soundness – who are virtious in aligning their judgements with a vision of the good life from which society and citizens can flourish.

Common reflection surface methods in low fold coverage seismic data of complex marine geological structures

The primary objective of seismic data processing is to generate seismic cross-section with an optimum signal to noise ratio to model geological structures imaging as accurately as possible with the actual condition. However, we may look onto complex geological structures with less than adequate number of fold coverage seismic data. In this study, Common Reflection Surface (CRS) method is applied to generate 2D marine seismic cross-sections with better reflector continuity of 3 (three) real data seismic lines. It is based on obtaining the suitable aperture value along the attributes namely RN, RNIP, and a. Its results are compared to conventional Common Mid-Point (CMP) ones. The final products are presented in multiple- attenuated and time-migrated cross-section with Surface Related Multiple Elimination (SRME) and Kirchhoff Migration techniques, respectively. Comparison of final time-migrated both CRS and CMP stacks show the CRS method is more effective and reliable to model accurate complex marine geological structures with high signal to noise ratio based on reflector continuity and noise reduction.

Overcoming “You Can Ask My Mom”: Clinical Arts-Based Perspectives to Include Children Under 12 in Mental Health Research

As research with children (rather than research on children) gains popularity and researchers adapt methods to include children’s voices, continual reflection on the research methods themselves is needed. In this article, we explore the relevance of playing and drawing in qualitative research interviews to include and represent the voice of children under 12 years of age, particularly in the field of mental health research. We reflect on the conception of children’s voice in research and argue for an understanding of voice that goes beyond verbal language. We suggest a combination of perspectives from arts-based research and clinical interview practice to support our understanding of children’s voice in research. As an illustration, we draw on an example taken from a large research project in Youth Mental Health Collaborative Care during which 23 children under the age of 12 were interviewed using a talk-play-draw model. We discuss the multidimensional aspect of children’s voices and the ethical value of arts and play in research interviews. We highlight the importance of researchers’ ethical reflexivity and creative participation in their quest to understand children’s voices. While doing so, we emphasize the responsibility of researchers to interpret, translate and represent as justly as possible a multi-layered, complex and often disorganized voice into a form that is accessible to the linear world of academic research. Given that it is perhaps inevitable that researchers use their own voice in this process, we argue that in conducting research with children, we need to engage both the children as participants and the researchers as advocates for children’s perspectives.

Driving Improvements in Child Protection and Safeguarding Practice

Driving Improvements in Child Protection and Safeguarding Practice

Data mining of petrophysical and lithogeochemical borehole data to elucidate the origin of seismic reflectivity within the Kevitsa Ni–Cu–PGE bearing intrusion, northern Finland

ABSTRACTThe Kevitsa mafic‐ultramafic intrusion, located within the Central Lapland Greenstone Belt in northern Finland, hosts a large, disseminated Ni–Cu–PGE sulphide deposit. A three‐dimensional seismic reflection survey was conducted over the Kevitsa intrusion in 2010 primarily for open‐pit mine planning and for deep mineral exploration purposes. In the Kevitsa three‐dimensional seismic data, laterally continuous reflections are observed within a constrained region within the intrusion. In earlier studies, it has been suggested that this internal reflectivity mainly originates from contacts between the tops and more sulphide‐rich bottoms of smaller scale, internally differentiated magma layers that represent a spectrum of olivine pyroxenites. However, this interpretation is not unequivocally supported by the borehole data. In this study, data mining, namely the Self‐Organizing Map analysis, of extensive Kevitsa borehole data is used to investigate the possible causes for the observed internal reflectivity within the Kevitsa intrusion. Modelling of the effect of mineralization and alteration on the reflectivity properties of Kevitsa rock types, based on average modal compositions of the rock types, is presented to support the results of the Self‐Organizing Map analysis. Based on the results, we suggest that the seismic reflectivity observed within the Kevitsa intrusion can possibly be attributed to alteration, and may also be linked to the presence of sulphide minerals.

Characteristic of Shallow Subsurface Quaternary Sediment in Nongsa Isle, Part of Putri Islands, Batam, Based on Georadar Data Interpretation

Nongsa Isle belongs to Putri Islands in Batam, is the outermost island that need to be protected either from natural hazards and anthropogenic factor. Therefore, this study was conducted by performing Ground Penetrating Radar analysis, in order to understand the geological condition particularly sedimentology and its process. We used Sirveyor 20 GPR equipment type with MLF antenna frequency 40 Mhz and Radan 5 as processing software, which include time zero correction, spatial filter, deconvolution, migration and adjustment of amplitude and signal gain. Data interpretation was conducted based on radar facies methodology that describes georadar image/radargram. The study result showed differences of sedimentary facies based on three differences of radar facies units, with the first layer (unit 1) is the youngest unit has thicknesses ranging from 3.5 – 5 m that characterized by parallel, strong reflector, high amplitude and continuous reflector configurations, unit 2 from 5 – 11 meter of depth, indicates parallel reflector pattern with medium-high amplitude and continuous, and unit 3 which is the oldest unit with thickness until penetration limit (11 – 20 m), characterized by a configuration of sub parallel – hummocky reflectors that are undulating, low-medium amplitude reflectors. Based on radar facies characteristics such as reflector configuration, reflection amplitude, and reflection continuity, the differencies of depositional facies are changes from fluvial – coastal plain.

Developing a curriculum model of English teaching for master’s degree nursing education in a Chinese medicine university

ObjectiveEnglish for Specific Purpose (ESP) is the essence for developing scientific research capacity, which is a core component for postgraduate education. The objective of this article is to develop a curriculum model for ESP of Master’s level nursing education in a Chinese medicine university. MethodA three-year action research approach with continuous reflection and modification was used to develop an ESP curriculum based on the RICH model. A total of 78 students of Master’s Science in Nursing enrolled in 2016–2018 and three course teachers in Nanjing University of Chinese Medicine participated in the study. The ESP curriculum based on the RICH model involved research-based learning topics (R), integrated curriculum(I), cooperative learning methods(C), and humanistic outcome (H). ResultsThe passing rate of the students was 100%, the excellent rate was 79.5%, with an average score of 83.16 ± 3.43. All students were satisfied with the ESP course design and acknowledged the process of “growing up under the pressure”. Four students have published five articles in the journals included by Science Citation Index (SCI). ConclusionsThe study exerted a positive effect on the ESP teaching and learning and provided new ideas for the ESP curriculum integration of Master’s Science in Nursing in China.

Section 4.c Introduction

Increasingly, designers are asked to play a role in innovation processes taking place in society, either by initiating new approaches to weave social tissue, by amplifying or scaling up existing initiatives or by creating the preconditions for these initiatives to prosper. In doing so, they touch upon new meanings and values that are about to emerge in society, often increasing their visibility and moving them towards the centre of our everyday lives. For instance, a new sense of community and citizenship emerges where designers attempt to increase citizen participation in co-designing new services for their cities. As time progresses, the meaning of notions such as politics, aesthetics and citizenship shift and designers need to adapt to these changes and help to initiate or steer the adaptation process. Thus, they no longer just work to create new services: they are engaging in a cultural operation (Margolin and Margolin’s 2002 and Manzini 2016). This raises important questions such as: Are we designers always aware of the cultural implications of our work? How to take these implications into account? Are we always aware of the shift of meanings and values to which we contribute when working on social innovation? Do we deal with it critically?
 Philosophy has traditionally dealt with the interpretation of meanings and values produced throughout history. As a discipline, it can help us to better frame the new meanings and values that we designers are uncovering, (re)shaping or amplifying in society. Which meanings and values are we talking about? Can philosophy help us to critically assess these new meanings and values, framing them culturally and increase our awareness of their implications on our culture? Can philosophy help to bring more critical awareness and continuous reflection in processes of social innovation? Which philosophical traditions are better suited to look into in this sense? How can these reflections help us in our design practice aimed at social innovation? This track puts into dialogue meanings and values emerging from practices of social innovation with diverse philosophical traditions.

Ground-penetrating radar measurements of subsurface structures of lacustrine sediments in the Qaidam Basin (NW China): Possible implications for future in-situ radar experiments on Mars

The stratigraphic profile of paleolakes on Mars preserves a record of past climatic, hydrological and sedimentary environment. Radar could be used to detect the structure and distribution of buried lacustrine sediments. But orbiter radar sounders rarely detect the internal structure or the bottom of the ancient Martian lake deposits. Future Martian missions will employ ground-penetrating radar (GPR) onboard rovers to investigate the shallow subsurface structure of paleolake basins. In this case, ground experiments are necessary to test the potential of GPR detection. This study reports on GPR experiments operating at 100 MHz and 200 MHz carried out in the Qaidam Basin, one of the analogue sites for Martian paleolake environments, to detect the subsurface structure of lacustrine sediments and measure the relative permittivity of sediments with both laboratory instrument and GPR data. Two GPR measurements were performed on top of yardangs representing layered lacustrine sedimentary outcrops. Another survey site is a polygonal patterned ground, which is a common landform in the Qaidam Basin and on Mars. The observations revealed by GPR experiments show that (1) sediments of three sites have varied compositions, density and porosity, and have a wide range of relative permittivity values, from 1.56 to 4.56; (2) the detection depth of our measurements could reach 20 m; (3) The interfaces between sedimentary layers can be seen in radargrams, but reflectors in radargrams may not always match with exposed layers of the yardang outcrops due to the undetected change of permittivity values or thin thickness of layers; (4) A distinct and continuous reflector is observed beneath the polygonal terrain which we interpret as a subsurface layer with low water/brine content. Our ground experiments suggest that a similar GPR on Martian rover could detect the near-surface structure of lacustrine sediments, e.g. deposition anomaly, interfaces of drastic permittivity change such as buried ice/brine considering that the design frequency is close to our equipment.

Seismic stratigraphy of a deep water basin in the Brazilian equatorial margin: the eastern portion of Potiguar Basin and Touros High

The Brazilian Continental Margin (BEM) deep-water regions contain important geological features, although the area is poorly explored beyond the continental shelf-break. The main objective of this study is to seismically characterize syn- and post-rift sequences and certain seamounts that are part of the Fernando de Noronha Ridge (FNR) in deep-water basins and are off of the shore of northeastern Brazil. We used 2D post-stack high-resolution seismic sections to distinguish syn-rift, post-rift, and drift tectono-depositional phases. Three seismic horizons (R1 to R3) could represent, respectively, the following: an acoustic basement top, a rift top, and a highstand system tract (drift). The syn-rift stage is marked by discontinuous parallel reflectors with low amplitude and low frequency, which are offset by normal faults in half-grabens. The post-rift and drift stages are characterized by continuous parallel reflectors with low to high amplitude and frequency. Chaotic seismic reflections within the seamounts indicate their volcanic origins. Volcanic intrusions affected syn-rift, post-rift, and drift sequences and partially confine the deep-water basin deposition. The magmatic event occurred once the preexistent material and the sediment deposited after the seamount rises were partially confined by the continental slope and the seamounts. Seismic stratigraphy interpretation and its correlation with volcanic activities indicate a relative chronological control relating the emplacement of the seamounts to the Early Eocene to Late Miocene. Volcanic episodes seem to have created volcanoclastic deposits marked by a disorganized/chaotic seismic pattern with few continuous reflectors, indicating interbedded magma flows with sedimentary material. This paper provides an initial observation regarding the deep-water basin deposits on syn- and post-rift stages in the NE portion of the BEM.

Towards a Reflexive Framework for Fostering Co—Learning and Improvement of Transdisciplinary Collaboration

Scholars in sustainability science as well as research funders increasingly recognize that a shift from disciplinary and interdisciplinary science to transdisciplinary (TD) research is required to address ever more complex sustainability challenges. Evidence shows that addressing real-world societal problems can be best achieved through collaborative research where diverse actors contribute different kinds of knowledge. While the potential benefits of TD research are widely recognized, its implementation remains a challenge. In this article, we develop a framework that supports reflection and co-learning. Our approach fosters monitoring of the collaboration processes, helps to assess the progress made and encourages continuous reflection and improvement of the research processes. The TD co-learning framework has four dimensions and 44 criteria. It is based on a substantial literature review and was tested in a Horizon 2020-funded research project ROBUST, which is applying experimental governance techniques to improve rural-urban relations in eleven European regions. The results demonstrate that the framework covers the key facets of TD collaboration and that all four broad dimensions matter. Each research-practice team reflected on how their collaboration is going and what needs to be improved. Indeed, the coordination team was able to see how well TD collaboration is functioning at a project level. We believe the framework will be valuable for actors involved in the planning and implementation of any type of multi-actor, interactive, innovation, transformation and action-oriented research project.

Harmonic Green functions for the Almaty apple

The parqueting reflection principle is suitable for constructing harmonic Green functions for certain plane domains with boundaries consisting of sub-arcs from circles and straight lines. The (continued) reflection at the boundary parts has to provide a parqueting of the complex plane. Occasionally, however, a parqueting of is not sufficient and multiple parqueting is required, e.g. for the disc sector with opening angle , where a double parqueting is needed, then compensated by applying the square root mapping. The parqueting-reflection principle is more convenient to apply than basing on the conformal invariance of the harmonic Green functions, see e.g., but sometimes the latter is applicable where the first is not. Here the situation is studied for the Almaty apple, a modified half disc. While the bigger of this cut disc is also requiring a double parqueting, for the smaller part a simple one suffices. However, for the bigger part a proper square root reduction to a simple parqueting is still to be determined in order to find the harmonic Green (and Neumann) function. The idea to use this disc cap for a parqueting of the complex plane has occured while two of the authors were visiting a monument of an apple in Almaty, the centre of an area full of wild apple trees considered as the locus of origin of the apple fruit.

Improving the health of the public: a transdisciplinary research study

BackgroundHealth improvement requires actors from many sectors to coproduce knowledge and policy to solve complex global public health challenges. Transdisciplinary approaches can be broadly defined as using a common conceptual framework to unite a variety of disciplines enabling the deepest collaboration across academic fields and with non-academic stakeholders. Our aim was to establish best practice transdisciplinary research methods for public health science (and related) research studies. MethodsWe did a literature review using the following search terms in OVID Medline to identify articles that had conducted transdisciplinary research studies: “1.transdiscip*.tw.; 2.Trans-discip*.tw.; 3.1 or 2; 4. Research.tw.; 5.stud*.tw.; 6.4 or 5; 7.health*.tw.; 8.3 and 6 and 7”. We included English-language papers from any academic discipline and country, from inception until May 27, 2019. Papers were included in the final analysis if they provided sufficient details to enable us to summarise the method of the transdisciplinary research taken. FindingsWe identified 528 studies, of which 41 were included. No defined guidelines for designing a transdisciplinary research project exist; however, most studies outlined an iterative approach involving continual reflection and adaptation of the research plan and included the following steps: extensive literature searches, reviewing all involved disciplines; development of a shared conceptual framework, a jargon-free visual schematic, which enables all stakeholders to understand and agree theory, concepts, and assumptions that underpin the research plan; implementation of data collection (normally mixed-methods approach); reframing discussion with stakeholders to present data and compare with existing literature and local setting; and identification and collective decision-making regarding potential solutions to problems. Several included studies stated that the key to successful transdisciplinary research projects was good communication and team working skills between researchers and with wider stakeholders. InterpretationTransdisciplinary research is a complex process that requires the continual reflection and adaptation of the research plan and conceptual framework. This process ensures that the project continues to be relevant, captures all aspects of the disciplines involved, and has the ability to tackle challenges that have a major influence on the health of the public. FundingRWA is supported by a Wellcome Trust Clinical Research Career Development Fellowship.

Deep learning-based fusion of Landsat-8 and Sentinel-2 images for a harmonized surface reflectance product

Landsat and Sentinel-2 sensors together provide the most widely accessible medium-to-high spatial resolution multispectral data for a wide range of applications, such as vegetation phenology identification, crop yield estimation, and forest disturbance detection. Improved timely and accurate observations of the Earth's surface and dynamics are expected from the synergistic use of Landsat and Sentinel-2 data, which entails coordinating the spatial resolution gap between Landsat (30 m) and Sentinel-2 (10 m or 20 m) images. However, widely used data fusion techniques may not fulfil community's needs for generating a temporally dense reflectance product at 10 m spatial resolution from combined Landsat and Sentinel-2 images because of their inherent algorithmic weaknesses. Inspired by the recent advances in deep learning, this study developed an extended super-resolution convolutional neural network (ESRCNN) to a data fusion framework, specifically for blending Landsat-8 Operational Land Imager (OLI) and Sentinel-2 Multispectral Imager (MSI) data. Results demonstrated the effectiveness of the deep learning-based fusion algorithm in yielding a consistent and comparable dataset at 10 m from Landsat-8 and Sentinel-2. Further accuracy assessments revealed that the performance of the fusion network was influenced by both the number of input auxiliary Sentinel-2 images and temporal interval (i.e., difference in image acquisition dates) between auxiliary Sentinel-2 images and the target Landsat-8 image. Compared to the benchmark algorithm, area-to-point regression kriging (ATKPK), the deep learning-based fusion framework proved better in the quantitative assessment in terms of RMSE (root mean square error), correlation coefficient (CC), universal image quality index (UIQI), relative global-dimensional synthesis error (ERGAS), and spectral angle mapper (SAM). ESRCNN better preserved the reflectance distribution as the original image compared to ATPRK, resulting in an improved image quality. Overall, the developed data fusion network that blends Landsat-8 and Sentinel-2 images has the potential to help generate continuous reflectance observations of higher temporal frequency than that can be obtained from a single Landsat-like sensor.

Joint Retrieval of Growing Season Corn Canopy LAI and Leaf Chlorophyll Content by Fusing Sentinel-2 and MODIS Images

Continuous and accurate estimates of crop canopy leaf area index (LAI) and chlorophyll content are of great importance for crop growth monitoring. These estimates can be useful for precision agricultural management and agricultural planning. Our objectives were to investigate the joint retrieval of corn canopy LAI and chlorophyll content using filtered reflectances from Sentinel-2 and MODIS data acquired during the corn growing season, which, being generally hot and rainy, results in few cloud-free Sentinel-2 images. In addition, the retrieved time series of LAI and chlorophyll content results were used to monitor the corn growth behavior in the study area. Our results showed that: (1) the joint retrieval of LAI and chlorophyll content using the proposed joint probability distribution method improved the estimation accuracy of both corn canopy LAI and chlorophyll content. Corn canopy LAI and chlorophyll content were retrieved jointly and accurately using the PROSAIL model with fused Kalman filtered (KF) reflectance images. The relation between retrieved and field measured LAI and chlorophyll content of four corn-growing stages had a coefficient of determination (R2) of about 0.6, and root mean square errors (RMSEs) ranges of mainly 0.1–0.2 and 0.0–0.3, respectively. (2) Kalman filtering is a good way to produce continuous high-resolution reflectance images by synthesizing Sentinel-2 and MODIS reflectances. The correlation between fused KF and Sentinel-2 reflectances had an R2 value of 0.98 and RMSE of 0.0133, and the correlation between KF and field-measured reflectances had an R2 value of 0.8598 and RMSE of 0.0404. (3) The derived continuous KF reflectances captured the crop behavior well. Our analysis showed that the LAI increased from day of year (DOY) 181 (trefoil stage) to DOY 236 (filling stage), and then increased continuously until harvest, while the chlorophyll content first also increased from DOY 181 to DOY 236, and then remained stable until harvest. These results revealed that the jointly retrieved continuous LAI and chlorophyll content could be used to monitor corn growth conditions.

Seismic geomorphology and sedimentology of a fluvial-dominated delta: Implications for the Neogene reservoirs, offshore Bohai Bay Basin, China

Fluvial-dominated deltas are common along modern and ancient coasts and act as important hydrocarbon reservoirs. In this paper, an integration of high-resolution three-dimensional seismic, well log, and core data are employed to investigate the seismic geomorphology, depositional facies, reservoir types, and controlling factors of fluvial-dominated delta deposition in the lower segment of the Minghuazheng Formation (N1mL), Bohai Bay Basin, China. Three typical seismic facies and seismic geomorphologic units are identified. Seismic facies 1 displays discrete high-amplitude reflection and a distinct U-shape incision. In plan form, this seismic facies shows a linear, dendritic, and sinuous morphology with high root-mean-square amplitudes. Seismic facies 2 occurs interspersed with seismic facies 1 and shows low-frequency and low-amplitude reflection. Seismic facies 3 shows a continuous high-amplitude reflection and uniform sheet-like morphology covering more than 10 km2 (>3.86 mi2). The N1mL was primarily deposited in the upper delta plain, lower delta plain, and delta front environments and is dominated by three major facies types: (1) distributary channel (seismic facies 1), (2) interdistributary bay (seismic facies 2), and (3) sheet sand (seismic facies 3). Among them, the distributary channel sandstones and sheet sandstones are the major reservoirs in the N1mL. Fluvial processes and lake level cycles were important factors in the development and distribution of reservoirs and traps in fluvial-dominated delta systems. Integration of the seismic geomorphology and a modern geomorphology investigation provide an effective way to predict the sandstone reservoirs and traps in fluvial-dominated delta systems.

Dimensionality reduction and hierarchical clustering in framework for hyperspectral image segmentation

The hyperspectral data contains hundreds of narrows bands representing the same scene on earth, with each pixel has a continuous reflectance spectrum. The first attempts to analysehyperspectral images were based on techniques that were developed for multispectral images by randomly selecting few spectral channels, usually less than seven. This random selection of bands degrades the performance of segmentation algorithm on hyperspectraldatain terms of accuracies. In this paper, a new framework is designed for the analysis of hyperspectral image by taking the information from all the data channels with dimensionality reduction method using subset selection and hierarchical clustering. A methodology based on subset construction is used for selecting k informative bands from d bands dataset. In this selection, similarity metrics such as Average Pixel Intensity [API], Histogram Similarity [HS], Mutual Information [MI] and Correlation Similarity [CS] are used to create k distinct subsets and from each subset, a single band is selected. The informative bands which are selected are merged into a single image using hierarchical fusion technique. After getting fused image, Hierarchical clustering algorithm is used for segmentation of image. The qualitative and quantitative analysis shows that CS similarity metric in dimensionality reduction algorithm gets high quality segmented image.