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الإعاقة العقلية : الماضي-الحاضر-المستقبل
ينقسم الكتاب إلى خمسة أجزاء، ويتناول الجزء الأول \"مقدمة الى الإعاقة العقلية\" يضم هذا الجزء مفاهيم ومنظورات تاريخية، وتعريف وتصنيف الإعاقة العقلية والتقييم بغرض التعريف ويتناول الجزء الثاني \"أساب الإعاقة العقلية\" ويضم العوامل الجينية والكروموسومية، الأسباب البيئية والنفسية والاجتماعية بينما الجزء الثالث يتناول \"خصائص الإعاقة العقلية\"الذي يضم الخصائص المعرفية والتعلمية، الخصائص التعليمية والنفسية والسلوكية، الخصائص المجتمعية والاسرية والعابرة للثقافات ثم يتناول الجزء الرابع \"الاعتبارات التعليمية\" ويشمل هذا الجزء التقييم التعليمي، والمحتوى التعليمي، والإجراءات التدريسية، والأماكن التعليمية وأخيرا الجزء الخامس \"مستقبل الإعاقة العقلية\" الذي يتناول المنظورات المستقبلية.
Book
Multi-Chroic Dual-Polarization Bolometric Detectors for Studies of the Cosmic Microwave Background
We are developing multi-chroic antenna-coupled Transition Edge Sensor (TES) bolometer detectors for Cosmic Microwave Background (CMB) polarimetry. Multi-chroic detectors increase focal plane area efficiency, and thus the mapping speed per focal plane area, and provide greater discrimination against polarized galactic foregrounds with no increase in weight or cryogenic cost. In each pixel, a silicon lens-coupled dual-polarized sinuous antenna collects photons over a two-octave frequency band. The antenna couples the broadband millimeter wave signal into microstrip transmission lines, and on-chip filter banks split the broadband signal into multiple frequency bands. Separate TES bolometers detect the power in each frequency band and linear polarization state. We will describe the design and performance of these devices and present optical data taken. Our measurements of dual-polarization pixels in multiple frequency bands show beams with percent-level ellipticity, and percent-level cross-polarization leakage. We will also describe the development of large arrays of these multi-chroic pixels. Finally, we will describe kilo-pixel arrays of these detectors planned for the future CMB experiments that will achieve unprecedented mapping speed.
Journal Article
multi-modeling approach to evaluating climate and land use change impacts in a Great Lakes River Basin
River ecosystems are driven by linked physical, chemical, and biological subsystems, which operate over different temporal and spatial domains. This complexity increases uncertainty in ecological forecasts, and impedes preparation for the ecological consequences of climate change. We describe a recently developed “multi-modeling” system for ecological forecasting in a 7600 km² watershed in the North American Great Lakes Basin. Using a series of linked land cover, climate, hydrologic, hydraulic, thermal, loading, and biological response models, we examined how changes in both land cover and climate may interact to shape the habitat suitability of river segments for common sport fishes and alter patterns of biological integrity. In scenario-based modeling, both climate and land use change altered multiple ecosystem properties. Because water temperature has a controlling influence on species distributions, sport fishes were overall more sensitive to climate change than to land cover change. However, community-based biological integrity metrics were more sensitive to land use change than climate change; as were nutrient export rates. We discuss the implications of this result for regional preparations for climate change adaptation, and the extent to which the result may be constrained by our modeling methodology.
Journal Article
The POLARBEAR Cosmic Microwave Background Polarization Experiment
The
polarbear
cosmic microwave background (CMB) polarization experiment has been observing since early 2012 from its 5,200 m site in the Atacama Desert in Northern Chile.
polarbear
’s measurements will characterize the expected CMB polarization due to gravitational lensing by large scale structure, and search for the possible B-mode polarization signature of inflationary gravitational waves.
polarbear
’s 250 mK focal plane detector array consists of 1,274 polarization-sensitive antenna-coupled bolometers, each with an associated lithographed band-defining filter and contacting dielectric lenslet, an architecture unique in current CMB experiments. The status of the
polarbear
instrument, its focal plane, and the analysis of its measurements are presented.
Journal Article
LiteBIRD: A Satellite for the Studies of B-Mode Polarization and Inflation from Cosmic Background Radiation Detection
LiteBIRD is a candidate satellite for a strategic large mission of JAXA. With its expected launch in the middle of the 2020s with a H3 rocket, LiteBIRD plans to map the polarization of the cosmic microwave background radiation over the full sky with unprecedented precision. The full success of LiteBIRD is to achieve
δ
r
<
0.001
, where
δ
r
is the total error on the tensor-to-scalar ratio
r
. The required angular coverage corresponds to
2
≤
ℓ
≤
200
, where
ℓ
is the multipole moment. This allows us to test well-motivated cosmic inflation models. Full-sky surveys for 3 years at a Lagrangian point L2 will be carried out for 15 frequency bands between 34 and 448 GHz with two telescopes to achieve the total sensitivity of 2.5
μ
K arcmin with a typical angular resolution of 0.5
∘
at 150 GHz. Each telescope is equipped with a half-wave plate system for polarization signal modulation and a focal plane filled with polarization-sensitive TES bolometers. A cryogenic system provides a 100 mK base temperature for the focal planes and 2 K and 5 K stages for optical components.
Journal Article
Optical coupling
This paper describes contributions to the CMBpol Technology Study Workshop concerning optical coupling structures. These are structures in or near the focal plane which convert the free space wave to a superconducting microstrip on a SI wafer, or to the waveguide input to a HEMT receiver. In addition to an introduction and conclusions by the editor, this paper includes independent contributions by Bock on Planar Antenna-Coupled Bolometers for CMB Polarimetry , by Gunderson and Wollack on Millimeter-Wave Platlet Feeds , and by Lee on Multi-band Dual-Polarization Lens-coupled Planar Antennas for Bolometric CMB polarimetry.
Journal Article
The LiteBIRD Satellite Mission: Sub-Kelvin Instrument
Inflation is the leading theory of the first instant of the universe. Inflation, which postulates that the universe underwent a period of rapid expansion an instant after its birth, provides convincing explanation for cosmological observations. Recent advancements in detector technology have opened opportunities to explore primordial gravitational waves generated by the inflation through “B-mode” (divergent-free) polarization pattern embedded in the cosmic microwave background anisotropies. If detected, these signals would provide strong evidence for inflation, point to the correct model for inflation, and open a window to physics at ultra-high energies. LiteBIRD is a satellite mission with a goal of detecting degree-and-larger-angular-scale B-mode polarization. LiteBIRD will observe at the second Lagrange point with a 400 mm diameter telescope and 2622 detectors. It will survey the entire sky with 15 frequency bands from 40 to 400 GHz to measure and subtract foregrounds. The US LiteBIRD team is proposing to deliver sub-Kelvin instruments that include detectors and readout electronics. A lenslet-coupled sinuous antenna array will cover low-frequency bands (40–235 GHz) with four frequency arrangements of trichroic pixels. An orthomode-transducer-coupled corrugated horn array will cover high-frequency bands (280–402 GHz) with three types of single frequency detectors. The detectors will be made with transition edge sensor (TES) bolometers cooled to a 100 milli-Kelvin base temperature by an adiabatic demagnetization refrigerator. The TES bolometers will be read out using digital frequency multiplexing with Superconducting QUantum Interference Device (SQUID) amplifiers. Up to 78 bolometers will be multiplexed with a single SQUID amplifier. We report on the sub-Kelvin instrument design and ongoing developments for the LiteBIRD mission.
Journal Article
Antenna-Coupled Bolometer Arrays for Measurement of the Cosmic Microwave Background Polarization
We are building antenna-coupled Transition Edge Sensor bolometer arrays to measure the polarization of the cosmic microwave background. 217 GHz prototype pixels have previously been characterized and showed promising performance (Myers et al. in Appl. Phys. Lett. 86:114103, [
2005
]). Our design uses a double slot dipole antenna and an integrated microstrip band defining filter. New devices have been tested which include on-chip test structures to improve our understanding of detector performance and guide future development. In parallel with this, large arrays of bolometers based on the prototype pixel design have also been constructed. The array pixels are a heterogeneous mixture of single band pixels at 90 GHz, 150 GHz, and 220 GHz and now incorporate dual-polarization antennas (Chattopadhyay and Zmuidzinas in IEEE Trans. Antennas Propag. 46:736, [
1998
]). Preliminary results from optical testing of array pixels are presented. These bolometer arrays will be used in the upcoming CMB polarization experiment P
olarbear
.
Journal Article
A Multi-Band Dual-Polarized Antenna-Coupled TES Bolometer
We are developing multi-band dual-polarized antenna-coupled transition edge sensor (TES) bolometers for observing Cosmic Microwave Background (CMB) polarization anisotropies. We have designed a prototype pixel that uses a dual-polarized log-periodic antenna on a silicon hemispherical lens. Each polarization is coupled onto a separate microstrip transmission line. Microstrip filters are used to divide the broadband output of this antenna into a set of narrow frequency bands centered at 90, 150, and 220 GHz with bandwidths of 20%. We report on the fabrication of these devices as well as the initial optical testing.
Journal Article
The POLARBEAR-2 and Simons Array Focal Plane Fabrication Status
We present on the status of POLARBEAR-2 A (PB2-A) focal plane fabrication. The PB2-A is the first of three telescopes in the Simons Array, which is an array of three cosmic microwave background polarization-sensitive telescopes located at the POLARBEAR site in Northern Chile. As the successor to the PB experiment, each telescope and receiver combination is named as PB2-A, PB2-B, and PB2-C. PB2-A and -B will have nearly identical receivers operating at 90 and 150 GHz while PB2-C will house a receiver operating at 220 and 270 GHz. Each receiver contains a focal plane consisting of seven close-hex packed lenslet-coupled sinuous antenna transition edge sensor bolometer arrays. Each array contains 271 dichroic optical pixels, each of which has four TES bolometers for a total of 7588 detectors per receiver. We have produced a set of two types of candidate arrays for PB2-A. The first we call Version 11 (V11) uses a silicon oxide (SiO
x
) for the transmission lines and crossover process for orthogonal polarizations. The second we call Version 13 (V13) uses silicon nitride (SiN
x
) for the transmission lines and cross-under process for orthogonal polarizations. We have produced enough of each type of array to fully populate the focal plane of the PB2-A receiver. The average wirebond yield for V11 and V13 arrays is 93.2% and 95.6%, respectively. The V11 arrays had a superconducting transition temperature (
T
c
) of
452
±
15
mK, a normal resistance (
R
n
) of
1.25
±
0.20
Ω
, and saturation powers of
5.2
±
1.0
pW and
13
±
1.2
pW for the 90 and 150 GHz bands, respectively. The V13 arrays had a superconducting transition temperature (
T
c
) of
456
±
6
mK, a normal resistance (
R
n
) of
1.1
±
0.2
Ω
, and saturation powers of
10.8
±
1.8
pW and
22.9
±
2.6
pW for the 90 and 150 GHz bands, respectively. Production and characterization of arrays for PB2-B are ongoing and are expected to be completed by the summer of 2018. We have fabricated the first three candidate arrays for PB2-C but do not have any characterization results to present at this time.
Journal Article