3,722 research outputs found
Modelling the Product Development performance of Colombian Companies
Organised by: Cranfield UniversityThis paper presents the general model of the Product Development Process (PDP) in the Metal mechanics
Industry in Barranquilla-Colombia, since this sector contributes significantly to the productivity of this
industrial city. This case study counted on a five-company sample. The main goal was to model the current
conditions of the PDP according to the Concurrent Engineering philosophy. The companies were selected
according to their productive profile, in order to contrast differences regarding the structure of their
productive processes, conformation of multidisciplinary teams, integration of different areas, customers and
suppliers to the PDP; human resources, information, technology and marketing constraints.Mori Seiki – The Machine Tool Compan
Impact of stress, fear and anxiety on the nociceptive responses of larval zebrafish
Both adult and larval zebrafish have been demonstrated to show behavioural responses to noxious stimulation but also to potentially stress- and fear or anxiety- eliciting situations. The pain or nociceptive response can be altered and modulated by these situations in adult fish through a mechanism called stress-induced analgesia. However, this phenomenon has not been described in larval fish yet. Therefore, this study explores the behavioural changes in larval zebrafish after noxious stimulation and exposure to challenges that can trigger a stress, fear or anxiety reaction. Five-day post fertilization zebrafish were exposed to either a stressor (air emersion), a predatory fear cue (alarm substance) or an anxiogenic (caffeine) alone or prior to immersion in acetic acid 0.1%. Pre- and post-stimulation behaviour (swimming velocity and time spent active) was recorded using a novel tracking software in 25 fish at once. Results show that larvae reduced both velocity and activity after exposure to the air emersion and alarm substance challenges and that these changes were attenuated using etomidate and diazepam, respectively. Exposure to acetic acid decreased velocity and activity as well, whereas air emersion and alarm substance inhibited these responses, showing no differences between pre- and post-stimulation. Therefore, we hypothesize that an antinociceptive mechanism, activated by stress and/or fear, occur in 5dpf zebrafish, which could have prevented the larvae to display the characteristic responses to pain
On-the-fly computation method in field-programmable gate array for analog-to-digital converter linearity testing
© 2018 Published by ITB Journal Publisher. This paper presents a new approach to linearity testing of analog-to-digital converters (ADCs) through on-the-fly computation in field-programmable gate array (FPGA) hardware. The proposed method computes the linearity while it is processing without compromising the accuracy of the measurement, so very little overhead time is required to compute the final linearity. The results will be displayed immediately after a single ramp is supplied to the device under test. This is a cost-effective chip testing solution for semiconductor companies, achieved by reducing computing time and utilization of low-cost and low-specification automatic test equipment (ATE). The experimental results showed that the on-the-fly computation method significantly reduced the computation time (up to 44.4%) compared to the conventional process. Thus, for every 100M 12-bit ADC tested with 32 hits per code, the company can save up to 139,972 Php on electricity consumption
Synthesis of γ-valerolactone from biomass-derived compounds by aqueous-phase processing using supported mono- and bimetallic catalysts
Course Recommendation based on Sequences: An Evolutionary Search of Emerging Sequential Patterns
To provide a good study plan is key to avoid students’ failure. Academic advising based on student’s preferences, complexity of the semester, or even background knowledge is usually considered to reduce the dropout rate. This article aims to provide a good course index to recommend courses to students based on the sequence of courses already taken by each student. Hence, unlike existing long-term course planning methods, it is based on graduate students to model the course and not on external factors that might introduce some bias in the process. The proposal includes a novel sequential pattern mining algorithm, called (ES)2P (Evolutionary Search of Emerging Sequential Patterns), that properly identifies paths followed by good students and not followed by not so good students, as a long-term course planning approach. A major feature of the proposed (ES)2P algorithm is its ability to extract the best k solutions, that is, those with a best recommendation index score instead of returning the whole set of solutions above a predefined threshold. A real study case is performed including more than 13,000 students belonging to 13 faculties to demonstrate the usefulness of the proposal not only to recommend study plans but also to give advices at different stages of the students’ learning process
New approaches for the design of low-complexity radix-based FFT and FHT algorithms
The discrete Fourier transform (DFT) and discrete Hartley transform (DHT) play a crucial role in one- and multi-dimensional digital signal processing applications. Traditionally, the main concern in the design of fast Fourier transform (FFT) and fast Hartley transform (FHT) algorithms has been the reduction of the arithmetic complexity. However, with the recent advances in the digital technology and the present demands of such transforms in low-power high-performance real-time applications, a more comprehensive treatment of the computational and structural complexities must be considered in the design of the algorithms. The objective of this thesis is to design one- and multi-dimensional FFT and FHT algorithms that address the problem of reducing the number of arithmetic operations, data transfers, address generations, and twiddle factor evaluations or accesses to the lookup table, while possessing features such as simplicity, regularity, modularity, easy indexing scheme, and butterfly-style and in-place computations that are highly desirable characteristics for software or hardware implementations of the algorithms. To achieve these objectives, radix-based algorithms are proposed by introducing new decomposition strategies, efficient index mappings, and by an appropriate use of the Kronecker product. A general decomposition method, which is based on the radix-2 approach, valid for any dimension and applicable to both the DHT and DFT, and which significantly reduces the complexity of the FHT algorithms, is proposed. This method enables us to develop multidimensional FHT and FFT algorithms. A new approach for computing the DFT and DHT using a unified structure is proposed by establishing a close relationship, valid for any dimension, between the radix-2 based FHT and FFT algorithms. An efficient method, based on the radix-2 approach, for pruning output samples of a 1-D or 2-D DFT is proposed by grouping in its 1-D or 2-D FFT algorithm all the stages that involve unnecessary operations into a single stage and by introducing a new recursive technique for the computations required in the resulting stage. A technique is presented to improve the performance of the radix-4, radix-8 and radix-16 FFT algorithms in terms of the number of twiddle factor evaluations or accesses to the lookup table without any increase in the computational or structural complexities of the algorithms. In order to take advantage of the lowest structural complexity provided by the radix-2 approach and reduced computational complexity offered by the radix-4 approach, a technique suitable for combining these two approaches is introduced in order to develop efficient 3-D FFT and FHT algorithms. A radix-2/8 approach for reducing the complexity in the computation of the 1-D DFT and DHT of lengths N = q {604} 2 m is proposed by appropriately mixing the radix-2 and radix-8 index maps. This approach is extended to 2-D and 3-D DFTs. It is shown that the proposed radix-2/8 approach is superior to all the other existing radix-based approaches in providing low-complexity 1-D, 2-D and 3-D FFT, and 1-D FHT algorithms
Cutaneous larva migrans with optic disc edema: a case report
<p>Abstract</p> <p>Introduction</p> <p>A rare case of optic disc edema associated with cutaneous larva migrans is presented. To the best of our knowledge, this has not been previously reported in literature. Joint management by ophthalmology and tropical medicine teams proved most beneficial for our patient, facilitating correct diagnosis, appropriate investigations and instigation of suitable treatment.</p> <p>Case presentation</p> <p>A 45-year-old Caucasian man, a naturalist, from the UK developed cutaneous larva migrans while in Kenya and presented to us with visual disturbance secondary to unilateral optic disc edema. This resolved after receiving a single dose of ivermectin and visual acuity reverted to normal.</p> <p>Conclusion</p> <p>To the best of our knowledge, optic disc edema associated with cutaneous larva migrans has not been previously reported. This case highlights the importance of taking relevant history of recent travel to endemic areas affected by the nematodes in patients presenting with optic disc edema, and pertinent questioning regarding non-ocular symptoms, including skin lesions. In this case, a history of recent foreign travel and treatment for skin lesions was crucial.</p
Seroprevalence and risk factors for bovine brucellosis in Jordan
We investigated the seroprevalence and risk factors for Brucella seropositivity in cattle in Jordan. The sera from 671 cows were randomly collected from 62 herds. The antibodies against Brucella were detected using a Rose Bengal plate test and indirect ELISA. A structured questionnaire was used to collect information on the cattle herds' health and management. A multiple logistic regression model was constructed to identify the risk factors for Brucella seropositivity. The true prevalence of antibodies against Brucella in individual cows and cattle herds was 6.5% and 23%, respectively. The seroprevalence of brucellosis in cows older than 4 years of age was significantly higher than that in the younger cows. The seroprevalence of brucellosis in cows located in the Mafraq, Zarqa and Ma'an governorates was significantly higher than that of the other studied governorates. The multiple logistic regression model revealed that a larger herd size (odd ratio <OR> = 1.3; 95% CI: 1.1, 2.6) and mixed farming (OR = 2.0; 95% CI: 1.7, 3.7) were risk factors for cattle seropositivity to Brucella antigens. On the other hand, the use of disinfectants (OR = 1.9; 95% CI: 1.1, 2.1) and the presence of adequate veterinary services (OR = 1.6; 95% CI: 1.2, 3.2) were identified as protective factors
Reduction in activity by noxious chemical stimulation is ameliorated by immersion in analgesic drugs in zebrafish
Research has recently demonstrated that larval zebrafish show similar molecular responses to nociception to those of adults. Our study explored whether unprotected larval zebrafish exhibited altered behaviour after exposure to noxious chemicals and screened a range of analgesic drugs to determine their efficacy to reduce these responses. This approach aimed to validate larval zebrafish as a reliable replacement for adults as well as providing a high-throughput means of analysing behavioural responses. Zebrafish at 5 days postfertilization were exposed to known noxious stimuli: acetic acid (0.01%, 0.1% and 0.25%) and citric acid (0.1%, 1% and 5%). The behavioural response of each was recorded and analysed using novel tracking software that measures time spent active in 25 larvae at one time. Subsequently, the efficacy of aspirin, lidocaine, morphine and flunixin as analgesics after exposure to 0.1% acetic acid was tested. Larvae exposed to 0.1% and 0.25% acetic acid spent less time active, whereas those exposed to 0.01% acetic acid and 0.1–5% citric acid showed an increase in swimming activity. Administration of 2.5 mg l−1 aspirin, 5 mg l−1 lidocaine and 48 mg l−1 morphine prevented the behavioural changes induced by acetic acid. These results suggest that larvae respond to a noxious challenge in a similar way to adult zebrafish and other vertebrates and that the effect of nociception on activity can be ameliorated by using analgesics. Therefore, adopting larval zebrafish could represent a direct replacement of a protected adult fish with a non-protected form in pain- and nociception-related research
Religious faith and psychosocial adaptation among stroke patients in Kuwait: A mixed method study
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2012 Springer Science+Business Media.Religious faith is central to life for Muslim patients in Kuwait, so it may influence adaptation and rehabilitation. This study explored quantitative associations among religious faith, self-efficacy, and life satisfaction in 40 female stroke patients and explored the influence of religion within stroke rehabilitation through qualitative interviews with 12 health professionals. The quantitative measure of religious faith did not relate to life satisfaction or self-efficacy in stroke patients. However, the health professionals described religious coping as influencing adaptation post-stroke. Fatalistic beliefs were thought to have mixed influences on rehabilitation. Measuring religious faith among Muslims through a standardized scale is debated. The qualitative accounts suggest that religious beliefs need to be acknowledged in stroke rehabilitation in Kuwait
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