3,886 research outputs found

    Novel Current-Conveyor-Based Universal Current-Mode Biquad Filter with Three Inputs and One Output

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    A novel universal current-mode filter with three inputs and one high imedance output is presented. The proposed circuit uses four plus-type second-generation current-conveyors, grounded resistors and grounded capacitors. The proposed circuit enjoys low active and passive sensitivities and independent control of the parameters ω0/Q0 using grounded resistors

    Physicochemical composition of hydro-distilled essential oil from coriander ( Coriandrum sativum L.) seeds cultivated in Pakistan.

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    This experiment describes the physiochemical composition of the essential oil derived from the seeds of coriander (Coriandrum sativum) cultivated in Pakistan. Hydrodistilled essential oil content from coriander seeds was found to be 0.15%. The physicochemical properties namely density (25°C), refractive index (25°C), acid value, ester value, and optical rotation (25°C) determined for the essential oil were found to be 0.8310, 1.4592, 4.0, 23.7, and +11.5 g/cm3, respectively. A total of 48 chemical constituents representing 90% of the essential oil tested were identified using Gas chromatographyflame ionization detector (GC-FID) and Gas chromatography-mass spectroscopy (GC-MS). Linalool with contribution of 69.60% was found to be the principal constituent. Other important components identified were: geranyl acetate (4.99%), γ-terpinene (4.17%), α-pinene (1.63%), anethol (1.15%) and pcymene (1.12%). The analyzed essential oil mainly comprised of oxygenated monoterpene hydrocarbons (80.83%), followed by monoterpene hydrocarbons (8.00%), sesquiterpene hydrocarbons (0.47%) and oxygenated sesquiterpene hydrocarbons (0.35%). Overall, the physicochemical attributes and chemical profile of the tested essential oil from Pakistan were reasonably comparable with those investigated for coriander seed essential oils from other regions of the world suggesting its potential for functional foods and cosmetics applications

    Key Performance Indicators for Sustainable Freight Transport and Scenario-based Impediments in Pakistan Freight Industry

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    Freight transport enables economic growth, market connectivity, and access to the global supply chain systems which contribute to the societal progress and inclusive development of a country. However, it may undermine the sustainable operations by incurring external costs, inefficiency, and economic losses due to non-reliability, poor services, and information systems. In this research study, the Key Performance Indicators (KPIs) for Sustainable Freight Transport Systems (SFTS) are discussed based on available literature review and standards of sustainability measurement in freight transport. Then, based on KPIs some of the scenario-based impediments are highlighted which hinder the performance of the freight transport in Pakistan for achieving sustainable development goals. The core impediments included are Strategic Determinants (SD), Information Systems (IS), Infrastructure Management Systems (IMS) and City Logistics (CL). The negative direct impacts of the key identified factors are also highlighted and linked with each scenario-based impediment. This research study would provide an opportunity for the stakeholders to get tangible idea for policy making and upgradation of the freight transport industry in the country. The highlighted implications will also be validated via expert surveys and Delphi-analysis in the future study.

    Descriptive Analysis of Human Emotions Based on Eye pupils

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    Facial emotional expressions are viewed as the most descriptive way to understand the human’s state of temperament during confronting communication. In this work numerous statistical approaches have been applied on human eye pupil with static images of Chicago face dataset (CFD) to analyze and classify the considered categories for emotions which are Happy, Fear, Anger and Neutral. The aim of this study is to develop the specific architecture for image processing domain after applying different enhancement techniques on human eye pupil for analysis & recognition of the facial expressions. This work is divided into three phases initially in the first phase data preprocessing is performed to prepare according to the requirement of work and also the color images are converted in to negative by applying the pixel intensity controlled mechanism. Second phase define the boundary to compute the feature by using Circular Hough Transform algorithm. Lastly statistical approaches are applied on extracted features to corporate the central point of pupil. This corporation the central point presents the effects of emotions. While comparing peoples of different Age groups it is concluded that pupil constricted on Anger at different levels on different age groups. If further it is discussed about cross cultural and gender wise comparison then Happy Emotion effects most and resulted towards dilated pupil same like that Anger emotion effects most on constricting the pupil size

    Actividad antioxidante de extractos de metanol al 80% y al 100% de semillas de cebada (Hordeum vulgare L.): estabilización del aceite de girasol.

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    The antioxidant potential of 100% and 80% methanol extracts from the seeds of three barley varieties (Jou 83, Jou 87 and Haider 93) was assessed. The extract yields from barley seeds ranged from 3.23% (Haider 93,100% methanol) to 5.31% (Jou 83, 80% methanol). The total phenolic contents, DPPH radical scavenging activity (IC50 values) and inhibition of linoleic acid oxidation of barley seed extracts (BSE) were determined to be 88.1-145.7 mg/100g, 90.8-168.6 μg/mL and 62.6-74.6%, respectively. The antioxidant effectiveness of BSE was also assessed by stabilizing sunflower oil (SFO) with BSE at a concentration of 600 ppm (oil weight basis). The stabilized (treated with extract) and the control (without extract addition) SFO samples were subjected to accelerated (oven heating at 60ºC for 30 days, 8 h heating cycle/day) storage. These were analyzed at regular intervals for the extent of oxidative changes according to the measurements of their contents of peroxide value, para-anisidine value, conjugated dienes and conjugated trienes. Generally, the 80% methanol extract of barely seeds demonstrated better antioxidant action than the 100% methanol extract. The antioxidant activity of BSE was also found to be considerably varied among the varieties tested. The present results suggest that antioxidant extracts from barely seeds might be used to protect vegetable oils from oxidation.El potencial antioxidante de extractos de metanol al 100% y el 80% de semillas de tres variedades de cebada (Jou 83, Jou 87 y Haider 93) fue evaluada. El rendimiento de los extractos de las semillas de cebada vario desde un 3.23% (Haider, 100% methanol) a un 5.31% (Jou 83, 80% metanol). El contenido total de fenoles, la actividad atrapadora del radical DPPH (valores IC50) y la inhibición de la oxidación del ácido linoleico de los extractos de semilla de cebada (BSE) fueron 88.1-145.7 mg/100g, 90.8-168.6 μg/mL y 62.6- 74.6%, respectivamente. La efectividad antioxidante de BSE fue también evaluada mediante su capacidad para estabilizar aceite de girasol con concentraciones de BSE de 600 ppm (respecto al peso del aceite). La muestras estabilizadas (tratadas con extractos) y el control (sin adición de extractos) SFO fueron tratadas bajo condiciones de almacenamiento acelerado (calentamiento en un horno a 60ºC durante 30 días y ciclos de calentamiento de 8 h/día). Estas fueron analizadas a intervalos regulares para evaluar la extensión de los cambios oxidativos mediante la medida del valor de peróxidos, valor de para-anisidina y los contenidos de dienos conjugados y trienos congujados. Generalmente, los extractos de semilla de cebada al 80% demostraron una mejor acción antioxidante que los extracto al 100% de metanol. La actividad antioxidante de BSE varió también considerablemente entre las distintas variedades ensayadas. Los presentes resultados sugieren que los extractos antioxidantes de semillas de cebada podrían ser usadas para proteger aceites vegetales de la oxidación

    Application of lamb waves (ultrasonic waves) in wear detection on aluminium plate / Nik Rosli Abdullah, Shahrul Azam Abdullah and Muhammad Hussain Ismail

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    Wear is a cause of failure in many engineering components and normally related to the surface roughness of the components surface. The wear rate is high when two rough surfaces are in relative motion compared to the motion involved by two smooth surfaces. Wear can normally be assessed by measuring the depth of wear scar or weighing the component loss. However this method cannot be used when the surface locate inside the machine or if occur on inner part of machine. This work focus on ultrasonic wave's application in order to detect surface roughness which is can relate to the wear phenomenon. Non-destructive Testing is defined as an inspection tool that used to detect internal defect, surface and discontinuities or flaws in materials without destroying their usefulness before it is used in a new design. In this work, there are two method used to detect a surface roughness at the different level of roughness on four specimens made by aluminium alloy. First measurement performs by using stylus profilometer then followed by ultrasonic waves propagation. Comparison between two them was made to draw the relationship of both methods. It is shows strong evidence that ultrasonic waves have a great potential in roughness/wear detection. The time travel from one point to another was recorded for all specimens then calculation of waves velocities show reduction when surface roughness increases. Here we have strong evidence to prove the rough surface absorb energy from waves after propagates through it

    Efecto de la salinidad en la producción y calidad del aceite de semilla de Moringa oleifera

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    Variation in the yield and composition of Moringa oleifera (M. oleifera) seed oil from two differently adopted (non-saline and saline) provinces of Pakistan was examined. Hexaneextracted M. oleifera seeds from saline and non-saline areas contained 33.50% and 32.79% oil yield, respectively. The analysis of variance (ANOVA) revealed no significant differences in the physical (refractive index (40 oC), color and specific gravity (24 °C) or chemical (iodine value, free fatty acid value, peroxide value, unsaponifiable matter, saponification value, conjugated diene and triene values and  p-anisidine value) characteristics of the oils obtained from both areas. The concentration of C18:1 and C16:0 was significantly (P < 0.001) higher whereas, that of C14:0 was lower in M. oleifera seed oils from the saline area. A tocopherol analysis demonstrated the concentration of α- and δ-tocopherol of Moringa seed oils to be significantly (P < 0.001) higher from the saline area. Whereas, the contents of γ-tocopherol was found to be significantly (P < 0.001) higher in the Moringa seed oils native to the non-saline area. Results from the present study revealed that salinity did not affect the oil content of M. oleifera seeds. Nevertheless, it might affect the tocopherol and fatty acid profiles of M. oleifera seed oil.Ha sido examinada la variación en la producción y composición del aceite de semilla de Moringa oleifera extraído a partir de semillas cultivadas en Pakistan con diferente concentración salina en el cultivo. La producción obtenida por extracción con hexano fue de 33.50% y 32.79% respectivamente para las semillas cultivadas en áreas con alto y bajo contenido salino. El análisis de la varianza (ANOVA) reveló la inexistencia de diferencias significativas entre las características físicas (índice de refracción a 40 °C, color y gravedad específica) y las químicas (índice de yodo, acidez libre, índice de peróxidos, materia insaponificable, índice de saponificación, valores de dienos y trienos conjugados e índice de p-anisidina) de los aceites procedentes de ambas áreas. En el área de mayor salinidad las concentraciones de C18:1 y C16:0 de los aceites de semilla de Moringa oleifera fueron significativamente mayores (P< 0.001), mientras que el de C14:0 fue significativamente menor. El análisis de tocoferoles demostró que las concentraciones de α- y δ-tocoferol eran superiores significativamente (P< 0.001) en los aceites procedentes de las áreas con alta salinidad, mientras que el contenido en γ-tocoferol fue superior significativamente (P< 0.001) en los procedentes del área de baja salinidad. Los resultados de este estudio muestran que la salinidad no afecta sobre el contenido en aceite de estas semillas. Sin embargo, puede afectar al contenido en tocoferoles y el perfil de ácidos grasos
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