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Sentence Annotation based Enhanced Semantic Summary Generation from Multiple Documents

Problem statement: The goal of document summarization is to provide a summary or outline of manifold documents with reduction in time. Sentence extraction could be a technique that is employed to pick out relevant and vital sentences from documents and presented as a summary. So there is a need to develop more meaningful sentence selection strategy so as to extract most significant sentences. Approach: This study proposes an approach of generating initial and update summary by performing sentence level semantic analysis. In order to select the necessary information from documents all the sentences are annotated with aspects, prepositions and named entities. To detect most dominant concepts within a document, Wikipedia is used as a resource and the weight of each word is calculated using Term Synonym Concept Frequency-Inverse Sentence Frequency (TSCF-ISF) measure. Sentences are ranked based on the scores they have been assigned and the summary is formed from the highest ranking sentences. Results: To evaluate the quality of a summary based on coverage between machine summary and human summary intrinsic measures called Precision and Recall are used. Precision is used to determine exactness whereas Recall is used to measure the completeness of the summary. Then our results are compared with LexRank Update summarization task and with the Semantic Summary Generation method. The ROUGE-1 measure is used to identify how well machine generated summary correlates with human summary. Conclusion: The performance of update summarization relies highly on measurement of sentence similarity based on TSCF-ISF. The experiment result shows that low overlap between initial summary and its update summary.

Thermal Comfort Assessment-A Study Toward Workers’ Satisfaction in a Low Energy Office Building

Problem statement: The government of Malaysia has raised their concerns towards the issue of workers comfort and workspace quality in a Low Energy Office (LEO) building. New energy efficient building concepts and technologies require a revision of comfort standards, to create a suitable thermal condition in avoiding occupant dissatisfaction, adverse effect on their productivity and overall building performance. Approach: Assessment was conducted using Babuc-A (Portable air quality monitor) and sets of questionnaire adapted from ASHRAE-2004 were 99 respondents selected using a stratified random sampling. Results: This study shows that the thermal comfort zone temperature was identified to be within the range of 21.6-23.6°C and relative humidity of 42-54%. Conclusion: The results suggested that the thermal condition was in the acceptable range of ISO7730 and a lower room temperature was preferred by Malaysian in an office environment compared with the temperature criteria cited in ASHRAE-55. To create an optimum comfortable workplace, temperature between 20-26°C and relative humidity between 40-60% must be maintained. Adequate ventilation must be provided at the minimum rate of 10 l/s of fresh air per person for general office space or every 10 m² of floor space.

Simplified Modeling, Analysis and Simulation of Permanent Magnet Brushless Direct Current Motors for Sensorless Operation

Problem statement: In this study, a simplified modeling and experimental analysis of Permanent Magnet Brushless DC (PMBLDC) motors for Sensorless operation using MATLAB/SIMULINK. This model provides a mechanism for monitoring and controlling the voltage, current, speed and torque response. Approach: BLDC motor is modeled as sub-blocks. The inverter and switching function are implemented as S-function builder block. The Sensorless scheme employs direct back emf based zero crossing detection technique. Results: The proposed model with Sensorless control technique with back emf zero crossing detection is tested in the BLDC Motor and the performance was evaluated. The simulated and experimental results show that the proposed modeling works quite well during starting and running conditions. Conclusion/Recommendation: The developed model consists of several independent sub-blocks, that can be used in the modeling of Permanent Magnet Sinusoidal Motor and induction motor. Hence the developed simulation model is a design tool to study the dynamic behavior of Sensorless Controlled Brushless DC Motor.

Providing Fairness to Mobile Workforces in an Automated Task Allocation Process: A Semantic Multi-agent Approach

Problem statement: Mobile Workforces (MW) unlike computational resources of an automated system are active but not passive entities. Therefore, an automated resource allocation system that deals with MWs should assign tasks to them fairly and in a comparatively equal manner. An unfair task allocation in a group will cause dissatisfaction, which in turn demotivates MWs who are supposed to work as a team. Approach: In an automated Mobile Workforce Brokering System (MWBS) tasks are automatically assigned to MWs at Run-Time phase of the system’s run. However, the environmental risks specifically risk of disconnection disrupts the task allocation process. Disconnection causes unfair task allocation when an MW must carry the next upcoming task according to a rotator work schedule, but he is disconnected. In this situation another MW has to perform the task in order to satisfy a pre-planned daily workload. Results: In this study we explore through the Run-Time phase of MWBS and explain how its underpinning ontology-driven coordination model tackles the risk of disconnection and improves the fairness in the task allocation process. Conclusion: Moreover, fairness rates in task allocation processes are compared between an existing system and MWBS and improvement in fairness rate is shown and analyzed for 4 consecutive periods (months) of the system’s run.

A Novel Approach in Malignancy Detection of Computer Aided Diagnosis

Problem statement: Breast cancer is one of the most dangerous diseases that cause innumerable fatal in the female society. Early detection is the only way to reduce the mortality. Due to variety of factors sometimes manual reading of mammogram results in misdiagnosis. So that the diagnosis rate varies from 65-85%. Various computer aided detection techniques have been proposed for the past 20 years. Even then the detection rate is still not high. Approach: The proposed method consists of the following steps preprocessing, segmentation, feature extraction and classification. Noise, Artifact and pectoral region are removed in a preprocessing step. Contrast enhancement and Sobel operator with segmentation algorithm is used to segment the mass region. Feature extraction is performed on the segmented image using gray level co-occurrence matrix and local binary pattern method. Extracted features are classified using support vector machine. The performance of the proposed system is evaluated using partest method. Results: Proposed algorithm shows 98.8% sensitivity and 97.4% Specificity. Conclusion: The proposed algorithm is fully automatic and will be helpful in assisting the radiologists to detect the malignancy efficiently.

An Investigation of Compressed Natural Gas Engine for Nitrogen Oxides Reduction

Problem statement: This study describes the use of Reformer Gas (RG) to alter NO_x emission in a CNG-fueled HCCI engine. Comparison with diesel, natural gas has a very high octane number (≈120) and high auto-ignition temperature (≈600°C). Composed mostly of methane, natural gas is the only common fuel to manifest relatively pure, single-stage combustion. Other fuels have stronger low-temperature reaction and the required entropy for main stage combustion can be obtained from the low temperature heat release as a result of compression to moderate pressure and temperature. In deviation, the methane molecule resists destruction by free radicals and produces negligible heat release at low temperature. In consequences, in CNG-fueled HCCI engines the activation energy required for auto-ignition must be obtained by extreme levels of charge heating and compression. This causes inherently to a high rate of heat release. HCCI operation with pure CNG fuel was attained but not really practical due to very high NO_x production. While HCCI operation is usually described as a low NO_x technique, the knocking behavior when running with pure CNG raised the peak combustion temperature to a value well above normal combustion and the critical Zeldovich NO_x production threshold, giving very high indicated NO_x emissions. Approach: One approach to improving these properties is to convert part of the base CNG fuel to Reformer Gas (RG). In this study, modified COMET engine was operated in HCCI mode using a mixture of CNG fuel and simulated RG (75% H₂ and 25% CO) can be produced on-board from CNG using low current and non-thermal plasma boosted fuel converter. Results: This study shows that despite of having various RG mass fractions, λ was the dominant factor in reducing NO_x production and increasing RG mass fraction had only a small effect on increasing NO_x. This disconnect between the overall equivalence ratio and RG fraction shows that the real benefit of the RG blending was to enable lean (high) operation. Higher λ also effectively reduced maximum pressure and maximum pressure rate. Conclusion: Note that due to the low achievable power levels, the NO_x emissions continue to be high and further combustion enhancements and more controlled combustion would be needed to make the CNG-fuelled HCCI engine practical.

Determination of Heavy Metals and Other Elements in Artisanal Gold Mining Soils

Problem statement: The possible exposure of heavy elements to life as a result of artisanal gold mining activities can be of great concern because of its associated effect on health. Approach: Soil samples from the artisanal gold mining sites of Awwal and Bagega villages in Kebbi and Zamfara states of Nigeria were collected and analyzed for heavy and other elements by X-Ray Fluorescence (XRF) technique. Ten of the element analyses are presented in this study, based on their toxicity levels. Results: Four of the ten elements (Pb, Si, Rb and Fe) showed relatively high concentrations. Two of these four elements presented, (Si and Pb) may pose latent and immediate hazards to health. Respiratory crystalline silica is the major element constituent of the ever-well-pronounced mining dusts of the two sites. Its form of occurrence portends irreversible health problem called silicosis and is well linked to cancer forming properties; both of which develop through latency periods. Pb at whatever concentration portends both immediate and long term hazards to women and children at the greatest risks of exposures. Conclusion: Based on the results presented, there exist a possibility of an immediate and long term health risks associated with the artisanal gold mining exercises in the two sites studied if the said uncoordinated and unprofessional activities of the miners are left unchecked."

Controller Based Observer in Switched System with Norm Bounded Uncertainty

Problem statement: This study discusses the robust stabilization of norm bounded discrete switched systems. Approach: The proposed method is using the second Lyapunov approach and the poly-quadratic function concept. The stabilization conditions are written through linear matrix inequality relations. The control law is based on a static output feedback with the use of a switched observer. The synthesis conditions of the controller are written in the form of linear matrix inequalities difficult to resolve by current numerical solvers. That’s why relaxations are proposed to mitigate the pessimism of LMI conditions obtained. Results: The poly-quadratic Lyapunov approach provides a constructive way to tackle uncertainty in the switched framework. The feasibility is illustrated by the example of discrete uncertain switched systems. Conclusion: With these results, the study of stability can be achieved for arbitrary switching laws, state-dependent, time dependent or generated by a controller. However, the implementation of the control law is possible only if the switching status is well known in real time.

Phyllanthus Amarus Facilitates the Recovery of Peripheral Nerve after Injury

Problem statement: Peripheral nerve injuries are associated with morbidity and outcomes of peripheral nerve repair are poor. Moreover, it can subsequently leads to economic or social disability. Recent findings have shown that oxidative stress plays an important role on the functional recovery retardation of peripheral nerve. However, the impairment mentioned earlier is counteracted by antioxidant. Therefore, this study was carried out to determine whether the alcohol-water extract of the aerial parts of P. amarus could facilitate the functional recovery in experimental models of peripheral nerve injury induced by sciatic nerve crush injury. Approach: Male mice, weighing 30-50 g, were orally given the extract at doses of 50, 100 and 200 mg kg^-1 BW for 2 weeks before and 4 weeks after crush injury at right sciatic nerve. They were determined the recovery of nerve every 3 days using Sciatic Function Index (SFI) as an index. At the end of the experiment, the injured nerve was determined the level of Malondialdehyde (MDA) and the activities of Superoxide Disease (SOD), Glutathione Peroxidase (GPx) and Catalase (CAT) enzymes. Results: The results showed that the extract improved SFI in accompany with the enhanced CAT and the decreased MDA. However, no significant changes in SOD and GPx activities were observed. Conclusion: The results obtained from the present study suggest that P. amarus extract may enhance the recovery partly via the decreased oxidation stress. It may possibly serve as the natural resource for developing health products to facilitate the recovery of peripheral nerve injury. However, further researches about the possible active ingredient and the precise underlying mechanism are still essential.

Physico-Chemical Characteristics of Date Seed Oil Grown in Sudan

Problem statement: Studies were conducted on the physical-chemical properties of Sudanese date seed oil extracted from two date palm cultivars (Phoenix dactylifera L.) ALBarakawi and Alqundeila. The extracted oil from ALBarakawi seeds weighed 6.833% w/w oil, Alqundeila oil extracted weighed 5.064% w/w. Approach: The physical properties of ALBarakawi oil were: viscosity: 17cp, refractive Index: 1.444, density: 0.9116 g cm^-3 color: Within the range 1. 6-11.1 (red-yellow). For Alqundeila the physical properties were: viscosity: 20cp, refractive index: 1.458, density: 0.9174 g cm^-3 color: 1.8-12.1 (red yellow). Results: The chemical properties were: Acid value 2.55, saponfication value 0.255 mg g^-1, iodine value 71.12 gm I₂/100 gm fat, peroxide value: 4.8 mg. Peroxide/Kgoil for ALBarakawi. For Alqundeila they were: acid value 2.47, saponfication value 0.267 mg g^-1 and iodine value 83.31gm I₂/100 gm fat, peroxide value: 7.4 mg Peroxide/Kgoil. In this study, High Performance Liquid Chromatography (HPLC) was utilized for the identification and quantification of vitamin E in these samples. The content of vitamin E for ALBarakawi was 5.821 and 6.054 ppm for Alqundeila. For the fatty acid content in these oils, Gas Chromatography-Mass Spectrometry (GC-MS) was used. The constituents of fatty acids (calculated % relative to total fatty acid constituents) in ALBarakawi were: Saturated lauric acid 37.10%, palmitic acid: 9.24%, Stearic acid 1.71%, Unsaturated fatty acids: Linoleic acid (Omega-6) 4.33%, Oleic acid (Omega-9) 32.66%. For Alqundeila, the found fatty acids were: Saturated lauric acid o.11%, Palmitic acid: o.42%, Stearic acid 46.93%. Conclusion/Recommendations: The elements types and contents in these oils were: Iron 0.27 ppm, Magnesium 0.204 ppm, Sodium 60 ppm, Potassium 470 ppm, Calcium 25 ppm, Selenium 34.4 ppb for ALBarakawi. The contents of these elements in Alqundeila were: iron 0.27 ppm Magnesium 0.07 ppm, Potassium 2.3 ppm, Selenium 12.6 ppb. The methods involved in this study covered, Gas Chromatography-Mass Spectrometry (GC-MS), High Performance Liquid Chromatography (HPLC), Atomic Absorption Spectroscopy (AAS) and Refractometry. Physico-chemical properties of date seed oil reported in this study were found similar to most of the early published results in this field.