Pembangunan dan penganalisisan aplikasi permohonan peruntukkan penyelenggaraan bangunan sekolah berasaskan proses pengurusan dalam kejuruteraan awam

Penyelenggaraan adalah aktiviti yang dilakukan secara berterusan bagi memastikan fungsi bangunan dapat dilaksanakan sebagaimana fungsinya secara normal. Penyelenggaraan bangunan sekolah adalah aktiviti rutin yang harus dijalankan memandangkan sekolah adalah lokasi pertama dalam pengembangan minda kanak�kanak. Namun begitu, kajian literatur menunjukkan terdapat beberapa masalah dalam pengurusan penyelenggaraan yang lazimnya diselia oleh ahli jawatankuasa penyelenggaraan sekolah. Antaranya ialah kegagalan mereka mematuhi Pekeliling Am Bil.2 Tahun 1995 dalam proses permohonan penyelenggaraan. Disebabkan permasalahan tersebut, tesis ini diwujudkan bagi membantu mereka dalam menyelesaikan sebahagian masalah yang dihadapi dengan cara membangunkan satu aplikasi permohonan penyelenggaraan sekolah berkomputer. Pembangunan aplikasi adalah menggunakan Microsoft Access. Aplikasi pertama yang dibangunkan adalah CoRTMaS di mana ia hanya tertumpu kepada penyelenggaraan bumbung dan tandas berdasarkan kepada kajian literatur yang mengatakan 2 komponen ini paling kerap mengalami kerosakan. Hasil soal selidik diuji menggunakan SPSS dan mendapati kadar ketepatan hasil kajian adalah α = 0.893. Walaupun hasil kajian CoRTMaS amat memuaskan, aplikasi SiPBaS dibangunkan bagi menambah baik fungsi aplikasi dalam CoRTMaS. Kesimpulannya, pembangunan aplikasi dapat menyumbang kepada kelancaran proses permohonan penyelenggaraan sekolah namun terdapat beberapa cadangan lanjutan yang dicadangkan bagi memantapkan aplikasi SiPBaS iaitu menjadikan aplikasi ini berfungsi secara atas talian, mewujudkan ruangan bagi memuat turun gambar kerosakan serta mewujudkan kod keselamatan untuk kontraktor terlibat

Hubungan di antara status Sosio Ekonomi (SSE) keluarga dengan pencapaian akademk : satu kajian ke at as pelajar aliran teknikal di Sekolah Menengah Teknik Negeri Sembilan

Kajian ini bertujuan untuk melihat hubungan di antara status sosio ekonomi (SSE) keluarga dengan pencapaian akademik di kalangan pelajar aliran teknikal. Kajian ini dijalankan ke atas pelajar tingkatan empat aliran teknikal di lima buah Sekolah Menengah Teknik di Negeri Sembilan iaitu Sekolah Menengah Teknik Tuanku Jaafar, Sekolah Menengah Teknik Juasseh, Sekolah Menengah Teknik Pertanian Rembau, Sekolah Menengah Teknik Ampangan dan Sekolah Menengah Teknik Port Dicksoa Seramai 350 orang pelajar terlibat dalam kajian ini dan dipilih secara rawak mudah. Analisis regresi mudah dan regresi berbilang digunakan untuk melihat hubungan di antara pembolehubah yang dikaji. Keseluruhan data kajian telah dianahsis menggunakan perisian Statistical Packages for the Social Sciences (SPSS) versi 11.5 dengan membuat pengiraan peratusan dan regresi. Dapatan kajian menunjukkan secara majoritinya, SSE mempunyai hubungan yang signifikan dengan tahap pencapaian akademik pelajar. Dengan itu dapat dirumuskan bahawa SSE mempengaruhi tahap pencapaian akademik pelajar aliran teknikal. Beberapa cadangan dikemukakan untuk panduan kajian selanjutnya

Single-electron current sources: towards a refined definition of ampere

Controlling electrons at the level of elementary charge $e$ has been demonstrated experimentally already in the 1980's. Ever since, producing an electrical current $ef$, or its integer multiple, at a drive frequency $f$ has been in a focus of research for metrological purposes. In this review we first discuss the generic physical phenomena and technical constraints that influence charge transport. We then present the broad variety of proposed realizations. Some of them have already proven experimentally to nearly fulfill the demanding needs, in terms of transfer errors and transfer rate, of quantum metrology of electrical quantities, whereas some others are currently "just" wild ideas, still often potentially competitive if technical constraints can be lifted. We also discuss the important issues of read-out of single-electron events and potential error correction schemes based on them. Finally, we give an account of the status of single-electron current sources in the bigger framework of electric quantum standards and of the future international SI system of units, and briefly discuss the applications and uses of single-electron devices outside the metrological context.Comment: 55 pages, 38 figures; (v2) fixed typos and misformatted references, reworded the section on AC pump

Design and fabrication of a novel wideband tem – cell for dielectric measurements

Dielectric properties measurement at microwave frequencies is required to illustrate how the electromagnetic waves propagate through the materials. Various methods have been used for the measurement of dielectric properties including both time and frequency domain methods. The existing systems are mainly based on coaxial probes, free space, and reflection/transmission method by using waveguide or coaxial cell and resonance techniques. Waveguide has the advantages of high power handling capability and low loss but it requires the sample to be machined out as fit as the cross section of the waveguide. Practically waveguides are not appropriate for lower frequencies due to the large size. Coaxial line technique has enough bandwidth but not easy to perform dielectric measurement for heavy and porous materials as concrete. It does not provide a uniform electromagnetic (EM) wave and the specimen needs to be in the shape of toroidal which is hard to achieve. In free space method a perfect normal plane wave is hard to achieve and as well as the diffraction effect of the sample edges cannot be avoided. In this project a novel wideband TEM cell in the frequency range from 50 MHz to 800 MHz based on parallel plate waveguide is presented suitable for transmission/reflection method. A specimen of dielectric material is put between the two parallel plates. The scattering parameters (S-parameters) of the two port line are measured using vector network analyzer. The Complex permittivity and permeability can be determined from the measured S-parameters using Nicolson-Ross-Weir (NRW) method. In order to validate the functionality of the parallel plate cell, the dielectric properties of Teflon is determined and shown. A good agreement among the experimental result, simulation result and the published values of the Teflon material is achieved. In addition to that the dielectric properties of concrete, wet and dry wood are investigated as well. Based on this agreement an original result of the dielectric properties of the concrete material is obtained and shown

Fast waveform metrology : generation, measurement and application of sub-picosecond electrical pulses

This thesis describes work performed at the National Physical Laboratory to improve the electrical risetime calibration of instruments such as fast sampling oscilloscopes. The majority of the work can be divided into four sections: development of an ultrafast optoelectronic pulse generator; measurement of fast electrical pulses with an electrooptic sampling system; de-embedding of transmission line and transition effects as measured at different calibration reference planes; and calibration of an oscilloscope. The pulse generator is a photoconductive switch based on low-temperature Gallium Arsenide, which has a very fast carrier recombination time. Sub-picosecond electrical pulses are produced by illuminated a planar switch with 200 fs optical pulses from a Ti: sapphire laser system. The pulses are measured using a sampling system with an external electro-optic probe in close proximity to the switch. The electro-optic sampling system, with a temporal resolution better than 500 fs, is used to measure the electrical pulses shape at various positions along the planar transmission line. The results are compared to a pulse propagation model for the line. The effects of different switch geometries are examined. Although the pulse generator produces sub-picosecond pulses near to the point of generation, the pulse is shown to broaden to 7 ps after passing along a length of transmission line and a coplanar-coaxial transition. For a sampling oscilloscope with a coaxial input connector, this effect is significant. Frequency-domain measurements with a network analyser, further electro-optic sampling measurements, and the transmission line model are combined to find the network transfer function of the transition. Using the pulse generator, the electro-optic sampling system and the transition knowledge, a 50 GHz sampling oscilloscope is calibrated. The determination of the instrument step response(nominal risetime 7 ps) is improved from an earlier value of 8.5 -3.5 / +2.9 ps to a new value of 7.4 -2.1 / +1.7 ps with the calibration techniques described

Superinductance and fluctuating two-level systems: Loss and noise in disordered and non-disordered superconducting quantum devices

In this thesis, we first demonstrate that a disordered superconductor with high kinetic inductance can realise a microwave low-loss, non-dissipative circuit element with impedance greater than the quantum resistance. This element, known as a superinductor, can suppress the fluctuations of charge in a quantum circuit.For this purpose, we fabricated and characterised 20 nm thick, 40 nm wide niobium-nitride nanowires and determined the impedance to 6.795 kΩ. We demonstrate internal quality factors Qi = 2.5e4 in nanowire resonators at single photon excitation, which is significantly higher than values reported in devices with similar materials and geometries. Moreover, we show that the dominant dissipation in our nanowires is not an intrinsic property of the disordered films, but can instead be fully understood within the framework of two-level systems.To further characterise these losses, we then explore the geometrical scaling, toward nanowire dimensions, of dielectric losses in superconducting microwave resonators fabricated with the same techniques and from the same NbN thin-film as the nanowire superinductors. For this purpose, we perform an experimental and numerical study of dielectric loss at low temperatures. Using 3D finite-element simulation of the Maxwell--London equations, we compute the geometric filling factors of the lossy regions in our resonator structures and fit the experimental data to determine the intrinsic loss tangents of its interfaces and dielectrics. Finally, we study the effect of two-level systems on the performance of various superconducting quantum circuits. For this purpose, we measure coherence-time fluctuations in qubits and frequency fluctuations in resonators. In all devices, through statistical analysis, we identify the signature of individual Lorentzian fluctuators in the noise. We find that fluctuations in qubit relaxation are local to the qubit and are caused by instabilities of near-resonant two-level-systems. Furthermore, when examining the low-frequency noise of three different types of superconducting resonator - one NbN nanowire, one Al coplanar waveguide, and one Al 3D cavity - we observe a similar power-law dependence of the Lorentzian switching time and amplitude on the circulating power in the resonators, suggesting a common noise mechanism in the three different types of devices

Dielectrics - Digest of literature, volume 28, 1964

Dielectric constants, dipole moments, relaxation times, conduction phenomena, insulating films, breakdown, materials, and applications of dielectrics - annotated bibliograph

The 25th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

Papers in the following categories are presented: recent developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; international and transnational applications of precise time and time interval (PTTI) technology with emphasis on satellite laser tracking networks, GLONASS timing, intercomparison of national time scales and international telecommunication; applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; application of PTTI technology to evolving military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communications satellites