Airborne lidar sensing of massive stony coral colonies on patch reefs in the northern Florida reef tract

In this study we examined the ability of the NASA Experimental Advanced Airborne Research Lidar (EAARL) to discriminate cluster zones of massive stony coral colonies on northern Florida reef tract (NFRT) patch reefs based on their topographic complexity (rugosity). Spatially dense EAARL laser submarine topographic soundings acquired in August 2002 were used to create a 1-m resolution digital rugosity map for adjacent NFRT study areas characterized by patch reefs (Region A) and diverse substratums (Region B). In both regions, sites with lidar-sensed rugosities above 1.2 were imaged by an along-track underwater videography system that incorporated the acquisition of instantaneous GPS positions. Subsequent manual interpretation of videotape segments was performed to identify substratum types that caused elevated lidar-sensed rugosity. Our study determined that massive coral colony formation, modified by subsequent physical and biological processes that breakdown patch reef framework, was the primary source of topographic complexity sensed by the EAARL in the NFRT. Sites recognized by lidar scanning to be topographically complex preferentially occurred around the margins of patch reefs, constituted a minor fraction of the reef system, and usually reflected the presence of massive coral colonies in cluster zones, or their derivatives created by mortality, bioerosion, and physical breakdown.     

基于FPGA的成像声纳FFT波束形成器设计

针对成像声纳波束形成器的特点,设计了一种基于FPGA的FF波束形成器.整个系统采用Altera公司的DSP Builder构建,FFT波束形成器采用基2-512点DIT-FF算法,并使用流水线技术、乒乓操作.在Altera StratixII FPGA EP2S90F78414硬件平台上测试,30 MHz系统时钟,在1...     

声呐数字记录设备并行接口卡设计

介绍了一种声呐信号处理机与数字记录设备间数据传输的解决方案。该方案以DSP为核心，利用处理机的LINK口和记录设备的数据口，将两者无缝地连接起来，实现了声呐数据的实时记录和回放。     

Mapping of coral reefs using hyperspectral CASI data; a case study: Fordata,Tanimbar, Indonesia

Airborne remote sensing with a CASI‐550 sensor has been used to map the benthic coverage and the bottom topography of the Pulau Nukaha coral reef located in the Tanimbar Archipelago (Southeast Moluccas, Eastern Indonesia). The image classification method adopted was performed in three steps. Firstly, five geomorphological reef components were identified using a supervised spectral angle mapping algorithm in combination with data collected during the field survey, i.e. benthic cover type, percentage cover and depth. Secondly, benthic cover mapping was performed for each of the five geomorphological components separately using an unsupervised hierarchical clustering algorithm followed by class aggregation using both spectral and spatial information. Finally, 16 benthic cover classes could be labelled using the benthic cover data collected during the field survey. The overall classification accuracy, calculated on the biological diverse fore reef, was 73% with a kappa coefficient of 0.63. A reliable bathymetric model (up to a depth of 15 m) of the Pulau Nukaha reef was also obtained using a semi‐analytical radiative transfer model. When compared with independent in‐situ depth measurements, the result proved relatively accurate (mean residual error: ?0.9 m) and was consistent with the seabed topography (Pearson correlation coefficient: 86%).     

A model comparison study to the imaging of submarine reefs with synthetic aperture radar

Signatures of submarine reefs near Heligoland in the North Sea were observed in airborne radar images recorded at L-, C- and X-bands on 14 November 1990 during rather high wind speed of 9 ms^-1. Predictions from various models of the imaging mechanism were compared to these observations. One of the models is the so-called weak hydrodynamic interaction theory (WHIT) model. It is fully two-dimensional in position as well as wavenumber space, so any surface current variation can be handled. Also more sophisticated scattering models than first-order Bragg scattering can be included. The model contains a number of parameterizations for the roughness length, the equilibrium wave height spectrum and the relaxation rate as well as different forms for the local relaxation source term. In the model intercomparison, the WHIT model performed not very well. It is shown here that this is due to the choice of the radial relaxation rate. In a sensitivity analysis it is shown that also the form of the relaxation source term is important. A linear source term may lead to unrealistically high positive hydrodynamic modulations (up to 50 dB) at some positions over the reefs for waves with a wavelength of about 0.6 m. Such effects do not occur in quadratic or cubic source terms, which are therefore to be preferred. The parameterizations chosen for the roughness length and the angular relaxation rate have little influence on the model results. Also shoaling may be neglected. A scattering model based on first iteration of the Stratton-Chu equation gives results similar to that of an improved two-scale model. When compared to the observations, good agreement is obtained at L-band, but at C- and X-bands the model underestimates the modulations. A number of possible causes is discussed, but additional data are needed to settle this question.     

Extracting objects from Ada83 programs: A case study

Reengineering legacy systems written in conventional procedural languages to equivelent OO systms makes software more maintainable and reliable.This paper proposes a method for extracting objects from legacy Ada83 systems using module features.Firest.metrics are developed to measure module cohesion.Then,effects on cohesion from changing module components are analyzed and rules about how to extract inheritance relations among objects are given.At the end of this paper,an object-extracting algorithm usin module features is proposed.     

Learning from optimization: A case study with Apache Ant

ContextSoftware architecture degrades when changes violating the design-time architectural intents are imposed on the software throughout its life cycle. Such phenomenon is called architecture erosion. When changes are not controlled, erosion makes maintenance harder and negatively affects software evolution.ObjectiveTo study the effects of architecture erosion on a large software project and determine whether search-based module clustering might reduce the conceptual distance between the current architecture and the design-time one.MethodTo run an exploratory study with Apache Ant. First, we characterize Ant’s evolution in terms of size, change dispersion, cohesion, and coupling metrics, highlighting the potential introduction of architecture and code-level problems that might affect the cost of changing the system. Then, we reorganize the distribution of Ant’s classes using a heuristic search approach, intending to re-emerge its design-time architecture.ResultsIn characterizing the system, we observed that its original, simple design was lost due to maintenance and the addition of new features. In optimizing its architecture, we found that current models used to drive search-based software module clustering produce complex designs, which maximize the characteristics driving optimization while producing class distributions that would hardly be acceptable to developers maintaining Ant.ConclusionThe structural perspective promoted by the coupling and cohesion metrics precludes observing the adequate software module clustering from the perspective of software engineers when considering a large open source system. Our analysis adds evidence to the criticism of the dogma of driving design towards high cohesion and low coupling, at the same time observing the need for better models to drive design decisions. Apart from that, we see SBSE as a learning tool, allowing researchers to test Software Engineering models in extreme situations that would not be easily found in software projects.     

Optimization of machining processes from the perspective of energy consumption: A case study

One of the primary objectives of sustainable manufacturing is to minimize energy consumption in its manufacturing processes. A strategy of energy saving is to adapt new materials or new processes; but its implementation requires radical changes of the manufacturing system and usually a heavy initial investment. The other strategy is to optimize existing manufacturing processes from the perspective of energy saving. However, an explicit relational model between machining parameters and energy cost is required; while most of the works in this field treat the manufacturing processes as black or gray boxes. In this paper, analytical energy modeling for the explicit relations of machining parameters and energy consumption is investigated, and the modeling method is based on the kinematic and dynamic behaviors of chosen machine tools. The developed model is applied to optimize the machine setup for energy saving. A new parallel kinematic machine Exechon is used to demonstrate the procedure of energy modeling. The simulation results indicate that the optimization can result in 67% energy saving for the specific drilling operation of the given machine tool. This approach can be extended and applied to other machines to establish their energy models for sustainable manufacturing.     

Strategic information systems planning: A case study from the financial services industry

Strategic Information Systems Planning (SISP) is an important topic for managers and researchers alike. However, there is evidence of a gap between SISP research and practice. Taking this situation as a motivation, we conducted an in depth case study on SISP to investigate this gap. The study was carried out in a German financial services company (FSC) over a period of five months in summer 2003. During this time, the enterprise situation and the information system (IS) practices situation of FSC were studied with respect to the SISP approach in place. Our findings confirm the hypothesis that practitioners largely ignore academic literature and do not use it in support of their SISP endeavours. This is all the more striking since FSC extensively used guidance from IS research in other fields such as systems analysis and software development. Our case study examines in detail two possible explanations for the gap: firstly a lacking transfer of academic knowledge to practice, and secondly deficiencies in the academic knowledge base itself. In fact, our observations highlight a disconnect between academic discussion and practical conduct. However, we found that the ignorance of academic literature on SISP is not primarily caused by a constrained knowledge transfer. In order to exclude communication barriers, we filtered the academic discussion according to the specific situation and the needs of FSC and translated it into practical recommendations. Nevertheless, the academic arguments we put forward hardly had any impact, either on IT managers’ thinking or on SISP practice at FSC. Though academic literature was partly perceived as inspiring, it was not regarded as a touchstone for SISP practice. Academia, in the eyes of FSC’s practitioners, ignores the “real problems” and thus is not accredited as a relevant source of advice. Moreover, in a final discussion with FSC’s senior IT executives we got the impression that the professional identity of FSC’s IT management – and more specifically the CIO’s role – was different from interpretations prevalent in academia. The academic discussion assumes the CIO to be an initiator of organisational innovations and driver of business strategy on the board. In contrast, we found that FSC’s CIO basically perceives her role as that of a service provider to business. While the different perceptions might be due to idiosyncrasies of FSC, related research provided additional empirical support for the conjecture of misleading academic assumptions about the role of IT management in practice.     

The influencing causes of software unavailability: A case study from industry

Software unavailability can lead to disastrous consequences ranging from delays and cancellation to a loss of millions of dollars of technology. However, research on the causes that can make systems unavailable is still little. The aim of this paper is to investigate such causes in an industrial context using 2 qualitative approaches ((a) interview and (b) retrospective analysis) using archival data and records from a student information system. As a result, connectivity, human, hardware, storage, and software were found to be the important categories of causes for the unavailability. Besides, the critical lessons to be learned that relate to activities of software management and software business are also discussed. This includes vendor support, systems documentation, health check process, licensing, and software updating or upgrading. To strengthen the claim that our findings are promising, we compare our main findings with those of a previous study. This study can generally assist software engineering people including engineers, developers, project managers, vendors. Additionally, this paper dis cusses the threats to the study's validity and suggests open problems for future research.     

A case study: the making ofPencil Test

The Advanced Technology Group at Apple Computer, Inc. recently produced an animation entitledPencil Test, created entirely with Macintosh II and Macintosh Plus equipment. This paper discusses the challenges and obstacles faced, and the set of solutions chosen in producing an animation on a platform that had not previously been utilized by the animation industry. Animation is both an entertaining and effective communication tool. The conclusions set forth in this paper present some of the issues that need to be addressed to facilitate easier creation of animation on personal computers.     

Building syntax graphs from syntax equations: A case study in modular programming

A system is described which inputs EBNF syntax equations as text, checks them and builds a corresponding syntax graph representation. An EBNF parser, with full error recovery, is included. The system is designed using the principles of modular decomposition and data abstraction, and is presented as a case study in the application of these principles to program design. The system is programmed in Pascal-plus, and has been used as a basis for the automatic generation of parsers.     

Mining methodologies from NLP publications: A case study in automatic terminology recognition

The task of reviewing scientific publications and keeping up with the literature in a particular domain is extremely time-consuming. Extraction and exploration of methodological information, in particular, requires systematic understanding of the literature, but in many cases is performed within a limited context of publications that can be manually reviewed by an individual or group. Automated methodology identification could provide an opportunity for systematic retrieval of relevant documents and for exploring developments within a given discipline. In this paper we present a system for the identification of methodology mentions in scientific publications in the area of natural language processing, and in particular in automatic terminology recognition. The system comprises two major layers: the first layer is an automatic identification of methodological sentences; the second layer highlights methodological phrases (segments). Each mention is categorised in four semantic categories: Task, Method, Resource/Feature and Implementation. Extraction and classification of the segments is formalised as a sequence tagging problem and four separate phrase-based Conditional Random Fields are used to accomplish the task. The system has been evaluated on a manually annotated corpus comprising 45 full text articles. The results for the segment level annotation show an F-measure of 53% for identification of Task and Method mentions (with 70% precision), whereas the F-measures for Resource/Feature and Implementation identification were 61% (with 67% precision) and 75% (with 86% precision) respectively. At the document-level, an F-measure of 72% (with 81% precision) for Task mentions, 60% (with 81% precision) for Method mentions, 74% (with 78% precision) for the Resource/Feature and 79% (with 81% precision) for the Implementation categories have been achieved. We provide a detailed analysis of errors and explore the impact that the particular groups of features have on the extraction of methodological segments.     

Vibrometry of industrial workers: A case study

Vibrometry was performed on 165 factory workers and supervisors in 18 different job classifications. A low vibrometry score indicates insensitivity to vibrations and thus potential compression neuropathy. Males had significantly higher scores than females. Subjective estimates of the job's repetitiveness, force requirement and wrist angle movement did not correlate significantly with the vibrometry score but pace did (self-paced jobs had higher scores). Questions relating to pain in the hands and numbness in the hands were significant predictors of the score. The conventional vibrometry score is the total from seven frequencies. Analysis shows only the top frequencies (125, 250, 500 Hz) are needed and possibly just 250 and 500 Hz.     

Influence of green creativity on organizations: A case study from the perspectives of leaders and subordinates

The sustainability framework has a strong influence on the policies, practices and procedures of companies. Green creativity plays a pivotal role in the development of initiatives and innovations for the environmental pillar of sustainability. Based on a survey applied to a Portuguese company with an accredited environmental management system (N = 146), the findings reveal that green creativity is influenced in different ways when analysed from distinct perspectives. The leader's green creativity is positively influenced by the subordinate's green self-efficacy and personal identification with the leader, whereas the subordinate's green creativity is positively influenced by their green passion and green self-efficacy, and the leaders' green creativity. This study shows that green creativity develops differentially according to distinct job positions and expectations that in practice must be complementary and synergistic for its effective development.     

Building a relatedness graph from Linked Open Data: A case study in the IT domain

The availability of encyclopedic Linked Open Data (LOD) paves the way to a new generation of knowledge-intensive applications able to exploit the information encoded in the semantically-enriched datasets freely available on the Web. In such applications, the notion of relatedness between entities plays an important role whenever, given a query, we are looking not only for exact answers but we are also interested in a ranked list of related ones. In this paper we present an approach to build a relatedness graph among resources in the DBpedia dataset that refer to the IT domain. Our final aim is to create a useful data structure at the basis of an expert system that, looking for an IT resource, returns a ranked list of related technologies, languages, tools the user might be interested in. The graph we created is a basic building block to allow an expert system to support the user in entity search tasks in the IT domain (e.g. software component search or expert finding) that goes beyond string matching typical of pure keyword-based approaches and is able to exploit the explicit and implicit semantics encoded within LOD datasets. The graph creation relies on different relatedness measures that are combined with each other to compute a ranked list of candidate resources associated to a given query. We validated our tool through experimental evaluation on real data to verify the effectiveness of the proposed approach.     

Preliminary research on customer satisfaction models in Taiwan: A case study from the automobile industry

For our research we applied the TCSI model to the automobile industry in Taiwan. The subjects of our research were consumers of new cars in Taiwan during the years 2006–2008. According to statistics provided by the Taiwan Transportation Vehicle Manufacturers Association (TTVMA) Toyota, Ford, Nissan, and Mitsubishi Motors made up for 79% of all cars sold in Taiwan from January through June, 2008. Questionnaires were issued randomly to four companies. We used structural equation modeling (SEM) to manifest the model’s suitability and develop a standard questionnaire to obtain the customer’s opinions. The conclusions reached provide valuable insight into the companies and industry and can help them to develop strategies to increase their competitiveness.     

Discovering dispatching rules from data using imitation learning: A case study for the job-shop problem

Dispatching rules can be automatically generated from scheduling data. This paper will demonstrate that the key to learning an effective dispatching rule is through the careful construction of the training data, \(\{\mathbf {x}_i(k),y_i(k)\}_{k=1}^K\in {\mathscr {D}}\), where (i) features of partially constructed schedules \(\mathbf {x}_i\) should necessarily reflect the induced data distribution \({\mathscr {D}}\) for when the rule is applied. This is achieved by updating the learned model in an active imitation learning fashion; (ii) \(y_i\) is labelled optimally using a MIP solver; and (iii) data need to be balanced, as the set is unbalanced with respect to the dispatching step k. Using the guidelines set by our framework the design of custom dispatching rules, for a particular scheduling application, will become more effective. In the study presented three different distributions of the job-shop will be considered. The machine learning approach considered is based on preference learning, i.e. which dispatch (post-decision state) is preferable to another.