213 research outputs found

    A Preliminary Study on Innovative Absorption Systems that Utilize Low-Temperature Geothermal Energy for Air-Conditioning Buildings

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    Air conditioning (A/C) systems driven by renewable energy have been studied extensively during the past decade as promising alternatives to conventional electricity-driven vapor compression A/C to alleviate stress on the grid as well as reduce CO2 emissions. Among the possible renewable energy sources to drive A/C systems, low-temperature geothermal heat ( \u3c 150°C/300°F) is quite underdeveloped despite its abundance in the United States and the unique advantage of steady output regardless of the weather compared to other renewable energy sources. A major barrier to wider utilization is the typically long distances between geothermal sources and potential end uses. In order to overcome this barrier, an innovative two-step geothermal absorption (TSGA) system was studied. With this system, the low-temperature geothermal energy is stored and transported at ambient temperature with an energy density of 360 kJ of cooling energy per kg of shipped LiBr/H2O solution (about three times higher than hot water for typical space heating applications). Key design parameters of a 900 ton TSGA chiller have been determined based on computer simulations with ORNL’s SorpSim software. A case study for applying the TSGA system at a large office building in Houston, TX indicates that, for a 10-mile distance from the geothermal site to the building, the simple payback of the TSGA system is 11 years compared with a conventional electric-driven chiller. To further improve the density of the transported energy, thereby reducing transportation cost and improving payback, a new system using 3-phase-sorption technology is proposed. In this system crystallized salt solution is used to boost the transported energy density. A preliminary study of this new system shows that the enhanced energy density has potential to significantly improve payback

    A review and comparison of efficient flooding schemes for on-demand routing protocols on mobile ad hoc networks (MANETs)

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    Since the basic components of ad hoc wireless networks are mostly battery-operated portable devices, power conservation is one of the central issues of such networks. Power-conservative designs for ad hoc networks pose many challenges due to the lack of central coordination facilities. Existing on-demand routing protocols perform route discovery by flooding the network with a query message requesting a route to the destination. Flooding is used because of its simplicity and greater success in finding the best route between the source and destination available at that time of route discovery. However, as flooding involves querying all reachable network nodes, frequent flooding can rapidly deplete the energy reserved at each node. In addition to consuming significant portions of the available network bandwidth. Further, as the number of communicating nodes increases, more congestion, contention, and collisions can be expected. This paper reviews and compares approaches for optimizing bandwidth efficiency of route discovery, where several efficient flooding schemes have been presented based on different techniques to solve the problems related with the traditional blind flooding

    A proposed cloud-based billers hub using secured e-payments system

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    Automation of several payment processes from start to end is a challenging task, particularly when multiple payments from online and offline billers are involved. In this paper, we introduced a new aggregator system to combine all billing system types, in which it is possible to pay invoices electronically. The proposed aggregator system was designed to be employed in a cloud-based Billers Hub (CBBH) developed by the central banks. Furthermore, many applications can be realized such as; deposit e-money, withdrawal e-money, and other applications. A Gateway translator is used to apply authentication rules, security, and privacy. The proposed system was employed in the Jordanian payment gateway and successfully fulfills its purpose

    SentiALG: Automated Corpus Annotation for Algerian Sentiment Analysis

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    Data annotation is an important but time-consuming and costly procedure. To sort a text into two classes, the very first thing we need is a good annotation guideline, establishing what is required to qualify for each class. In the literature, the difficulties associated with an appropriate data annotation has been underestimated. In this paper, we present a novel approach to automatically construct an annotated sentiment corpus for Algerian dialect (a Maghrebi Arabic dialect). The construction of this corpus is based on an Algerian sentiment lexicon that is also constructed automatically. The presented work deals with the two widely used scripts on Arabic social media: Arabic and Arabizi. The proposed approach automatically constructs a sentiment corpus containing 8000 messages (where 4000 are dedicated to Arabic and 4000 to Arabizi). The achieved F1-score is up to 72% and 78% for an Arabic and Arabizi test sets, respectively. Ongoing work is aimed at integrating transliteration process for Arabizi messages to further improve the obtained results.Comment: To appear in the 9th International Conference on Brain Inspired Cognitive Systems (BICS 2018

    NY-ESO-1-Specific Circulating CD4+ T Cells in Ovarian Cancer Patients Are Prevalently TH1 Type Cells Undetectable in the CD25+FOXP3+Treg Compartment

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    Spontaneous CD4+ T-cell responses to the tumor-specific antigen NY-ESO-1 (ESO) are frequently found in patients with epithelial ovarian cancer (EOC). If these responses are of effector or/and Treg type, however, has remained unclear. Here, we have used functional approaches together with recently developed MHC class II/ESO tetramers to assess the frequency, phenotype and function of ESO-specific cells in circulating lymphocytes from EOC patients. We found that circulating ESO-specific CD4+ T cells in EOC patients with spontaneous immune responses to the antigen are prevalently TH1 type cells secreting IFN-γ but no IL-17 or IL-10 and are not suppressive. We detected tetramer+ cells ex vivo, at an average frequency of 1∶25000 memory cells, that is, significantly lower than in patients immunized with an ESO vaccine. ESO tetramer+ cells were mostly effector memory cells at advanced stages of differentiation and were not detected in circulating CD25+FOXP3+Treg. Thus, spontaneous CD4+ T-cell responses to ESO in cancer patients are prevalently of TH1 type and not Treg. Their relatively low frequency and advanced differentiation stage, however, may limit their efficacy, that may be boosted by immunogenic ESO vaccines

    Gait and Computerized Dynamic Posturography (CDP) Aspects in Early Progressive Supranuclear Palsy (PSP) - A Case Report

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    BACKGROUND: Posture and gait instability may cause of morbidity in individuals with progressive supranuclear palsy (PSP). OBJECTIVE: To quantitatively measure balance control by using computerized dynamic posturography (CDP) and to assess gait analysis in early PSP.CASE REPORT: She was evaluated for Berge balance scale, Functional Independence Measure (FIM) and postural stability using CDP device in early PSP with still able to walk or stand unassisted. Also, Gait analysis was conducted using an 8 M-camera Vicon 612 data capturing system set. Berge balance scale improved from 41/56 to 48/56. The score of FIM improved from 71/126 points to 95/126 points in early PSP. In CDP analysis, there was a decrease of composite equilibrium score (38 %). There was an increase of composite equilibrium score (59%) after three months of treatment. In gait analysis, there was no difference of gait parameters after three months of treatment in early PSP.CONCLUSIONS: Both CDP and gait analysis are important quantitative tools in the assessment of posture and gait instability as well as allow for early disclosure of the failure of the postural control system in early PSP

    Analyzing D-wave quantum macro assembler security

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    As we enter the quantum computing era, security becomes of at most importance. With the release of D-Wave One in 2011 and most recently the 2000Q, with 2,000 qubits, and with NASA and Google using D-wave Systems quantum computers, a thorough examination of quantum computer security is needed. Quantum computers underlying hardware is not compatible with classical boolean and binary-based computer systems and software. Assemblers and compliers translate modern programming languages and problems into quantum-annealing methods compatible with quantum computers. This paper presents a vulnerability assessment utilizing static source code analysis on Qmasm Python tool. More specifically, we use flow-sensitive, inter-procedural and context-sensitive data flow analysis to uncover vulnerable points in the program. We demonstrate the Qmasm security flaws that can leave D-Wave 2X system vulnerable to severe threats

    Analyzing D-wave quantum macro assembler security

    Get PDF
    As we enter the quantum computing era, security becomes of at most importance. With the release of D-Wave One in 2011 and most recently the 2000Q, with 2,000 qubits, and with NASA and Google using D-wave Systems quantum computers, a thorough examination of quantum computer security is needed. Quantum computers underlying hardware is not compatible with classical boolean and binary-based computer systems and software. Assemblers and compliers translate modern programming languages and problems into quantum-annealing methods compatible with quantum computers. This paper presents a vulnerability assessment utilizing static source code analysis on Qmasm Python tool. More specifically, we use flow-sensitive, inter-procedural and context-sensitive data flow analysis to uncover vulnerable points in the program. We demonstrate the Qmasm security flaws that can leave D-Wave 2X system vulnerable to severe threats

    Relationship between Gait Parameters and Postural Stability in Early and Late Parkinson's Disease and Visual Feedback-Based Balance Training Effects

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    BACKGROUND: Gait disorders or postural instability has been done before. However, lack of reviews has addressed the relation between gait and postural stability in Parkinson's disease (PD).AIM: The aim was to evaluate the relation between gait parameters and postural stability in early and late stages of PD.MATERIALS AND METHODS: The forty-one idiopathic PD patients were divided into two groups into a group (A) considered as early PD and group (B) considered as late ambulant PD. They were evaluated for postural stability by computerised dynamic posturography (CDP) device and gait analysis using an 8 m-camera Vicon 612 data capturing system set.RESULTS: There was a statistically significant improvement of composite equilibrium score, the composite latency of motor response, walking speed and cadence after treatment as compared to before training (p < 0.05) in early PD. However, in the late PD, there was a non-significant change of previous parameters after treatment as compared to before training (p > 0.05).There was a significant correlation between UPDRS motor part score, walking speed and composite equilibrium score after training in early PD (p > 0.05).CONCLUSIONS: Both gait analysis and CDP are important quantitative assessment tools of gait and posture instability

    Ultrasonographic Enthesopathy and Disease Activity in Psoriatic Arthritis

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    BACKGROUND: To our knowledge, the correlation between ultrasonographic enthesopathy and severity in psoriatic arthritis (PsA) has been done before. However, the correlation between ultrasonography of enthesopathy and the Psoriatic Arthritis Disease Activity Score (PASDAS) have not been done.AIM: To compare the results of ultrasonographic enthesopathy of foot and PASDAS in PsA.MATERIALS AND METHODS: A total of 65 PsA patients were involved and divided into two groups. The first group of 35 active PsA and the second group of 30 ages and sex matched inactive PsA as a control group were recruited in this study. Both groups were evaluated by examination, radiological findings and ultrasonography.RESULTS: Of 70 entheses in 35 active PsA patients, the most entheseal abnormalities were tender plantar fascia (18.5%), tender Achilles tendon (37.8%). PASDAS was a direct highly significant correlated with plantar fascia and Achilles tendon thickness in in active PsA (r = 0.823 and r = 0.796, p < 0.001 respectively).CONCLUSION: Musculoskeletal US is an accurate and low-cost method for assessment of enthesopathy with significant correlation to disease activities in psoriatic arthritis
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