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Polymeric Detector
Abstract The aim of this paper is to find the effect of Nd: YAG laser of wavelength (532 nm), laser power 150 MW on the CR-39 polymer. Twenty three detectors were divided in to three sets. The first set (ten detectors) (postexposed) was first exposed to alpha radiation from 241 Am source at 3MeV and then treated in air with laser at different exposure time started from 10 minutes to 100 minutes with ten minutes differ between them (alpha + laser). For the second set (ten detectors) (pre-exposed), the process was reversed (laser +alpha) under the same conditions, for the last set (three detectors) (un-exposed to laser), used as a control set, was irradiated with an alpha source (241Am). Alpha track diameters, bulk etching velocity (V B ), track etching velocity (V T ), etching efficiency (η), etching ratio (V) were determined. The activation energies of bulk etch (E B ) and track etch (E T ) for unexposed, postexposed and pre-exposed are found to be equal to 1.10, 0.92, 0.82 eV and 1.07, 0.86, 0.79 eV respectively
GABOR TRANSFORM IN QUANTUM CALCULUS AND APPLICATIONS
Abstract In this work, using the q-Jackson integral and some elements of the qharmonic analysis associated with zero order q-Bessel operator, for a fixed q ∈]0, 1[, we study the q analogue of the continuous Gabor transform associated with the q-Bessel operator of order zero. We give some q-harmonic analysis properties (a Plancherel formula, an L 2 q (R q,+ , xd q x) inversion formula, etc), and a weak uncertainty principle for it. Then, we show that the portion of the q-Bessel Gabor transform lying outside some set of finite measure cannot be arbitrarily too small. Finally, using the kernel reproducing theory, given by Saitoh [13], we give the q analogue of the practical real inversion formula for q-Bessel Gabor transform. Mathematics Subject Classification: 33D15, 42C15 (main), 44A15, 33
IMECE2008-67512 INVESTIGATION INTO BIO-AVIATION REACTION MECHANISMS USING QUANTUM MECHANICAL METHODS
ABSTRACT Using high level model chemistries the C-C and C-H bond dissociation energies for methyl butanoate molecule (MB) were estimated using the Gaussian 03 program at the CBS-QB3 level of calculations. This consequently located the weaker bonds more likely to break. Thermal decomposition of MB over the temperatures 500 to 2000 K was theoretically studied and the rate constants for these channels were calculated. Crucial reactions in combustion, among which there are reactions of the fuel molecule with flame reactive radicals OH and CH 3 , were studied and the barrier heights for reactions including different hydrogen atoms transferring to the radicals were evaluated at the B3LYP/6-31+G(d,p) level of theory. The rate constants for these reactions are calculated over the temperatures 500 to 2000 K using the same level
Prevalence and correlates of zinc deficiency in pregnant Vietnamese women in Ho Chi Minh City
Background: Although Vietnam is a region with a plant-based diet that has a high zinc deficiency, epidemiological data showing how this affects pregnant women are limited. This study explores the prevalence of zinc deficiency and possible correlates in pregnant Vietnamese women in Ho Chi Minh City. Methods: This was a crosssectional study conducted at a general hospital in Ho Chi Minh City, Vietnam. All pregnant women who came to their first antenatal care visit from November 2011 to June 2012 were recruited. Those taking a vitamin and/or mineral supplement were excluded. Serum zinc concentrations, determined by a standard colorimetric method, of 10.7 mol/L-17.5 mol/L (70.0 g/dL-114 g/dL) were classified as normal and under 10.7 mol/L (70.0 g/dL) as zinc deficient. Results: In total, 254 pregnant women were invited and 107 (42%) participated. The mean age of participants was 29 years, and mean gestational age was 10 weeks. Median zinc concentration in serum was 13.6 mol/L, and the prevalence of zinc deficiency was 29% (95% CI=21%-39%). The daily intake of a milk product supplement was the only significant correlate of zinc deficiency of the items investigated (adjusted OR=0.40, p=0.049). Discussion: This is the first study reporting that more than 25% of pregnant Vietnamese women in Ho Chi Minh City are zinc deficient. Further academic and clinical input is needed to confirm the scale of this neglected issue and to investigate the potential of milk product supplementation in this population
SMASIS2010-3651 ACTIVE VIBRATION ISOLATION SYSTEM USING THE PIEZOELECTRIC UNIMORPH WITH MECHANICALLY PRE-STRESSED SUBSTRATE
ABSTRACT In this paper, a pre-stressed piezoelectric unimorph made by a new fabrication method in room temperature, and an active vibration isolation system using the pre-stressed unimorph actuators are introduced. The fabricated piezoelectric unimorph, called PUMPS (piezoelectric unimorph with mechanically pre-stressed substrate), is an actuator in which actuation level is enhanced by displacement amplification mechanism that converts piezoelectric extension and contraction to large bending/pumping motion without sacrificing the actuation force. Preliminary vibration tests were performed to check the performance of PUMPS as actuators for active vibration control in a lab environment. Two feedback control schemes, the positive position feedback (PPF) and negative velocity feedback (NVF), were applied for active vibration control. Using a smart vibration isolation system with improved load capacity obtained by stacking pre-stressed piezoelectric unimorph actuators, about 10dB vibration reduction of the system was achieved near the resonant frequency region. With the preliminary vibration test results showing promising performance of PUMPS actuator in active vibration control, an integrated active vibration isolation system composed of PUMPS actuators is developed. The developed system contains compact analogue circuits and a sensor for PUMPS actuation and control, and power is supplied by Li-Polymer battery which means the system is completely standalone and portable. In addition, an integrated jitter isolation demonstration system was developed to demonstrate the degrading effect of jitter and the effectiveness of the developed integrated active vibration isolation system in improving the performance of optical payloads. Comparison of image qualities taken before and after the operation of vibration control system indicates that effective suppression of vibration disturbances can be achieved using the developed vibration isolation system with PUMPS actuators
EFFICIENT APPROACH FOR WIRELESS SENSOR NETWORKS TO IMPROVE LIFE TIME USING ANYCAST
Abstract-This paper describe the topic based on minimizing the delay and maximizing the lifetime of event-driven wireless sensor networks, for which events occur infrequently. In such systems, most of the energy is consumed when the radios are on, waiting for an arrival to occur. Sleep-wake scheduling is an effective mechanism to prolong the lifetime of these energy-constrained wireless sensor networks. However, sleep-wake scheduling could result in substantial delays because a transmitting node needs to wait for its next-hop relay node to wake up. An interesting line of work attempts to reduce these delays by developing any cast.-based packet forwarding schemes, where each node opportunistically forward]s a packet to the neighboring node that wakes up among multiple candidate nodes. In this paper, we first study how to optimize the any cast forwarding schemes for minimizing the expected packet-delivery delays from the sensor nodes to the sink. Based on this result, we then provide a solution to the joint control problem of how to optimally control the system parameters of the sleep-wake scheduling protocol and the any cast packet-forwarding protocol to maximize the network lifetime, subject to a constraint on the expected end to end packet-delivery delay. Our numerical results indicate that the proposed solution can outperform prior heuristic solutions in the literature, especially under the practical scenarios where there are obstructions, e.g., a lake or a mountain, in the coverage area of wireless sensor networks
COMPARISON OF THE ACOUSTIC PROVISIONS IN THE NATIONAL BUILDING CODE WITH THE ACOUSTIC BUILDING CODES OF SOME SELECTED COUNTRIES
Abstract There are three problems that this present generation has to find solution to: Poverty, Population and Pollution. Industrialisation and urbanisation have taken the problems of noise pollution to an unprecedented catastrophic level both in the developed and the developing nations of the modern world. While the advanced countries have taken some legislative measures in the form of Acoustics Building Codes to control the problem of noise and its attendant effects, developing nations like Nigeria may not have fared well in this regards. This paper, therefore, is an attempt to compare the building codes in some selected countries of the world with emphasis on the acoustics regulations of the building codes. The countries include: the United Kingdom, United States of America, New Zealand, Australia and Nigeria. The building codes of these nations will be compared with that of Nigeria in terms of acoustics regulatory provisions. A building code, according to Wordnet 3.0, is a set of standards established and enforced by local governments for the structural safety of buildings. Farlex (2011) defined building code as 'systematic statement of a body of rules that govern and constrain the design, construction, alteration, and repair of buildings'. The essence of building codes are for the protection of public health, safety and general welfare of the occupants of buildings and non-building structures. The codes are meant to proffer lasting solutions to the hazardous trends in the building industry. These problems might have resulted from planlessness of the built environment, use of non-professionals, use of substandard materials, insufficient referenced design standard for professional and lack of adequate regulations and sanctions against offenders Noise can be defined as an unwanted sound and acoustics as the science of sound in general. However, acoustics is more commonly and technically used to describe the special branch of that science of sound. Architectural acoustics, however, deals with the science of sound as it pertains to buildings. The three major branches of architectural acoustics are: 1. Room acoustic which deals with the design of the interior of buildings for appropriate levels and qualities for music and speech; 2. Noise control or management which involves the reduction and control of noise between noise source and a listener; and 3. Sound reinforcement and enhancement systems which involve the use of electronic equipment to improve the quality of sounds heard in rooms. The nuisance of noise is regarded as a health and safety issue for persons living in dwellings and all occupants of a dwelling should be allowed to follow normal domestic activities, including sleep and rest, without threat to their health from noise. Noise is transmitted in buildings by both airborne and impact sound sources, hence, both of these noise types should be controlled. Practical guidelines to ensure this should be provided in the relevant section of the building codes of every country. Sound insulation, in general terms, is the prevention of airborne and impact sound being transmitted from one part of the building to another through separating floors, ceilings or/and walls. Statement of the Research Problem The current patterns of urbanization and human activities have led to environmental degradation, and have created serious threat to continuous human existence (George, 2008). The rate of urbanization and industrialisation of the urban cities with its attendant high level of noise pollution is affecting the quality of life in the built environment. Hence, there is need to evaluate the adequacy of the provisions of the national building code with respect to noise control by comparing its provisions with that of some selected countries. Research Aim The aim of this study is to compare the Acoustic Building Codes of some selected countries with the acoustic provisions of the National Building Code of Nigeria with a view to identify areas of improvement required in the National Building Code for the betterment of the built environment. Research Objectives To achieve this aim, the following objectives have been set out; to: i. review the Acoustic Building Codes of some selected countries, ii. review the National Building Code of Nigeria, and iii. compare the provisions for noise regulations in the national building code with the provisions in the acoustic building codes of these selected countries. Scope of the Study The scope of the research is limited to acoustic related issues in the selected building codes. Hence, only issues related to noise control and regulations in these codes shall be reviewed with a view to draw comparison with that of the national building code. Research Methodology The research method adopted for this study is essentially literature review and analysis of secondary data collected through internet surfing and relevant literatures. The selected countries are New Zealand, England, United States of America and Australia. The codes of these countries were selected based on their advancement in legislative matters, especially in areas of noise control. Research Questions This research intends to provide answers to the following questions: i. What do the building codes of these selected countries specify with regards to acoustics? ii. Do these building codes have provisions for noise control and regulations? iii. How does the National Building Code of Nigeria compare with other building codes in terms of acoustics provisions? Acoustics Building Codes of Selected Countries Building Code of New Zealand Introduction: The Building Code of New Zealand is a schedule to the building regulation, 1992 (Consumer Build, n.d.). The code is a performance-based code. It sets out performance standard that building work must meet, and covers aspects such as structural stability, fire safety, access, moisture control, durability, services and facilities. The Building Code consists of two preliminary clauses and 35 technical clauses. Each technical clause contains: 1. Objective -The social objective that completed building work must achieve 2. Functional requirement -What the completed building work must do to satisfy the social objective 3. Performance criteria -Qualitative or quantitative criteria which nominates how far the completed building work must go in order to comply Sikiru Abiodun Ganiyu 3 The Requirements: The section of the New Zealand Building Code that deals with acoustics is clause G6 under the title "Airborne and Impact Sound". It is aimed at safeguarding people from illness or loss of amnesty as a result of undue noise being transmitted between abutting occupancies or common spaces to habitable spaces of household units. It requires separating wall, floor and ceiling elements to have a sound transmission class (STC) of not less than 55 dB and the floors must have an impact insulation class (IIC) rating of not less than 55. According to Clause G6/VM1, the performance of the airborne sound in the building code may be verified in accordance with ASTM E 336 (measurement) and ASTM E 413 (rating) while the performance for the impact sound insulation may be verified using the International Organization for Standardization ISO 140: Part VII (measurement) and ASTM E 989 (rating). Verification Method G6/VM1 states that field (F) test results shall be within 5 dB of the performance requirements, and the general market interpretation of this is that onsite measurements of field sound transmission class (FSTC) 50 and FIIC 50 satisfy the requirements of the Building Code. The provisions of this code are limited to habitable spaces within apartments intended for permanent living and do not apply to non-habitable spaces, temporary accommodation, offices and external or environmental sound. England and Wales Acoustic Code Requirements The section that deals with acoustics regulation for United Kingdom is given within the approved document, Part E, under "Resistance to the passage of sound (England and Wales) 2003" which require that both airborne and impact sound sources were controlled (Building Regulations, 2010). The Part E of the code focussed on four major areas: a. E1: Protection against sound from other parts of the building and adjoining buildings b. E2: Protection against sound within a dwelling house c. E3: Reverberation in the common internal parts of buildings containing flats or rooms for residential purposes d. E4: Acoustic conditions in schools. To ensure compliance, there are two routes: 1. Robust Details for new buildings which require no pre-completion testing. It is designed to achieve higher sound insulation standards than the minimum requirements in Part E. Each approved Robust Detail contains a checklist which must be completed on site. This is a quality control check to confirm that all the critical factors that affect sound performance have been built correctly. 2. Pre-completion Testing for all new buildings, refurbishment, remedial and extension work in buildings with rooms for residential purposes. Part E of the building code calls for precompletion testing of separating walls and floors before handover to ensure that the level of performance specified is being achieved. The tests are to be performed on a minimum of one in every ten dwellings of the same type before completion and to meet the standards of ISO 140 series. Portland, Oregon continues to innovate through their almost 35years old Noise Control Office at the City's Bureau of Development Services. Today, their code is still one of the only comprehensive codes in the USA that not only regulates based on a given decibel level, but also includes sound limitations based on the specific pitch or frequency of the given noise. United States of America Acoustics Building 2. Local Noise Ordinances: This is principally aimed at construction noise, power equipment of individuals and unmuffled industrial noise penetrating residential areas. Thousands of USA cities have prepared noise ordinances that give noise control officers and police the power to investigate noise complaints and enforcement power to abate the offending noise source, through shutdowns and fines. In the 1970's and 1980's, there was even a professional association for noise enforcement officers called "National Association of Noise Control Officials" (NANCO). Today, only a handful of properly trained Noise Control Officers remain in the United States. A typical noise ordinance sets forth clear definitions of acoustic nomenclature and defines categories of noise generation; then numerical standards are established, so that enforcement personnel can take the necessary steps of warnings, fines or other municipal police power to rectify unacceptable noise generation. Ordinances have achieved certain successes but they can be thorny to implement. 3. USA Acoustic Code Requirements: In the case of construction of new (or remodelled) apartment, condominiums, hospitals and hotels, many US states and cities have stringent building codes with requirements of acoustical analysis, in order to protect building occupants from : (a) exterior noise sources and, (b) sound generated within the building itself. 4. Exterior Noise: With regards to exterior noise, the codes usually require measurement of the exterior acoustical environment in order to determine the performance standard required for exterior building skin design. The architect can work to arrive at the best cost effective means of creating a quiet interior (normally 45dBA). The most important elements of design of the building skin are usually: glazing (glass thickness, double pane design, etc.), roof materials, caulking standards, chimney baffles, exterior door design, mail slots, attic ventilation ports and mounting of through the wall air conditioners. A special case of building skin design arises in the case of aircraft noise, where the FAA has funded extensive work in residential retrofit. 5. Interior Noise: Regarding noise generated inside the building, there are two principal types of transmission. Firstly, airborne sound travels through walls or floor/ceiling assemblies and can emanate from either human activities (e. g. voice, amplified sound systems or animal noise) in adjacent living spaces or from mechanical noise (e. g. elevator systems, boilers, refrigeration or air conditioning systems, generators, and trash compactors) within the Sikiru Abiodun Ganiyu 5 building systems. The principle of regulation requires the wall or ceiling assembly to meet certain performance standards (Sound Transmission Class of 50), which allows considerable attenuation of the sound level reaching occupants. The second type of interior sound is called Impact Insulation Class (IIC) transmission. This effect arises not from airborne transmission, but from transmission of sound through the building itself. The most perception of IIC noise is from footfall of occupants in living spaces above. Commonly a performance standard of IIC equal to 50 is specified in building codes. 6. Occupational Regulations: The U.S. Occupational Safety and Health Administration has established maximum noise levels for occupational exposure, beyond which mitigation measures or personal protective equipment is required. Noise Criteria (NC) are noise level guidelines applicable to cinema and home cinema. It is a measure of a room's ambient noise level at various frequencies. The Requirements of the Code: The Building Code of Australia (BCA) requires that the acoustic performance of a construction system (Rw) and correction factor relating lower to medium frequency noise (Rw + Ctr) should be determined in accordance with AS/NZS 1276.1 using results from laboratory measurements. The Code classifications for acoustic performance are categorized based on the building type as Class 1, Class 2 or Class 3, etc. Class 1 buildings include single dwellings that do not have another dwelling above or below it, such as a stand-alone house or a row of townhouses. Class 2 buildings include buildings that contain two or more sole-occupancy units, such as an apartment unit. Class 3 buildings include residential buildings that contain a number of unrelated persons, such as a guest house or the residential part of a school, hotel, etc. The Code requires common walls separating building units to have an Rw + Ctr of not less than 50. In addition, the construction must be discontinuous, if the wall separates a habitable room (living room, dining room, bedroom, study and the like) from a wet room (kitchen, bathroom, sanitary compartment or laundry). Discontinuous construction requires: A minimum 20mm cavity between two separate leaves 2. Resilient wall ties such as those provided by Matrix Industries, if the wall is masonry, and 3. No mechanical linkage if the walls are not masonry. The weighted sound reduction index (Rw) describes the acoustic performance of a construction system. It is a single number quantity for the airborne sound insulation rating of building elements. As the acoustic performance of a material or construction improves, the higher the Rw value will be. This means that certain sound performance levels for different building situations are specified. Rw ratings are determined by laboratory tests of a specimen of the construction system. Correction factors (C and Ctr) can be added to Rw to take into account the characteristics of particular sound spectra and indicate the performance drop of the wall in the corresponding sound frequency range. The factor C relates to mainly mid to high frequency noise, whilst Ctr relates to lower to medium frequency noise. Some typical noises have been grouped by their corresponding correction factor as shown in the table 1