While tracking balloons for wind characterization, there was a question about the theoretical rise rate and corresponding coefficient of drag of a balloon shape as compared to a sphere. Since there are many studies published detailing the drag on spherical shapes, the question of whether or not a balloon can be treated as a sphere begged to be answered. In this study we apply Computational Fluid Dynamic (CFD) modeling to compare the aerodynamic behavior and drag of a sphere to that of a balloon as it moves through fluid at Reynolds numbers from 10,000 to 100,000. Fluent CFD models are created and used to estimate the coefficient of drag (Cd) vs. Reynolds number (Re) for a sphere and for a balloon shape. Details are given for the meshed model creation and the simulation methods. Sphere model results are compared to data provided in published literature. Sphere and balloon model results are compared to each other. The results of this study show that the drag on a balloon is not statistically different from a sphere. While there are differences in the flow characteristics over the two shapes, a spherical shape is a good approximation for a balloon shape.

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This study investigates the emergence of civil society in China. The existence and sustainability of civil society in China has bearing on the countrys further economic, political and social development. Using a mix of qualitative and quantitative methods, this study employs secondary statistical data as well as individual and focus groups interviews to address the emergence of civil society and intellectuals in China. The position of this paper is that Chinese civil society has developed in fits and starts since the beginning of economic liberalization in 1978. This contributed to changes in the political and social spheres, allowing more autonomous bodies to grow out of society as well as state structures, and facilitating the emergence of Chinese civil society. Intellectuals in particular have been able to exercise their autonomy in the Chinese policy process, influencing the direction of state policy towards their own interests, and consequently strengthening the public sphere and civil society.<p> Chinese civil society is punctuated by the influence of the historical, cultural, and political factors that constitute the form of its institutions, organizations and associations, as well as how these social actors communicate in the public sphere. It differs from that generally found in western countries. Unlike the west, it does not exist in opposition to the state. Instead, Chinese institutions of civil society also exist at the interstices between state and society and across them as well. This entwining entanglement of civil society with the state is indicative of the specific social, political, economic, and cultural conditions that have contributed to its development.<p> As it continues to emerge, Chinese civil society is increasingly becoming a sphere of identity formation, social integration, and cultural reproduction.

Multiple Input Multiple Output (MIMO) systems are a key technology for next generation high speed wireless communication standards like 802.11n, WiMax etc. MIMO enables spatial multiplexing to increase channel bandwidth which requires the use of multiple antennas in the receiver and transmitter side. The increase in bandwidth comes at the cost of high silicon complexity of MIMO detectors which result, due to the intricate algorithms required for the separation of these spatially multiplexed streams. Previous implementations of MIMO detector have mainly dealt with the issue of complexity reduction, latency minimization and throughput enhancement. Although, these detectors have successfully mapped algorithms to relatively simpler circuits but still, latency and throughput of these systems need further improvements to meet standard requirements. Additionally, most of these implementations don’t deal with the requirements of reconfigurability of the detector to multiple modulation schemes and different antennae configurations. This necessary requirement provides another dimension to the implementation of MIMO detector and adds to the implementation complexity. This thesis focuses on the efficient VLSI implementation of the MIMO detector with an emphasis on performance and re-configurability to different modulation schemes. MIMO decoding in our detector is based on the fixed sphere decoding algorithm which has been simplified for an effective VLSI implementation without considerably degrading the near optimal bit error rate performance. The regularity of the architecture makes it suitable for a highly parallel and pipelined implementation. The decoder has intrinsic traits for dynamic re-configurability to different modulation and encoding schemes. This detector architecture can be easily tuned for high/low performance requirements with slight degradation/improvement in Bit Error Rate (BER) depending on needs of the overlying application. Additionally, various architectural optimizations like pipelining, parallel processing, hardware scheduling, dynamic voltage and frequency scaling have been explored to improve the performance, energy requirements and re-configurability of the design.

Shading devices are frequently used to control solar gain through windows. Solar optical properties are very important in the energy analysis of windows. Transmittance, absorptance and reflectance are required to quantify solar heat gain through complex fenestration systems, which consist of combinations of glazing and shading layers. In this research the solar transmittance of a sheer blind was measured using a Broad Area Illuminating Integrating Sphere (BAI-IS). More specifically, the spectral directional-hemispherical transmittance was measured in the wavelength range of 0.4 µm to 2.0 µm. A “sheer blind” consists of soft fabric vanes, similar to a venetian blind, suspended between two vertical layers of sheer fabric. This arrangement is popular because it is attractive and it has potential application for daylighting. The vertical sheer fabric reduces the solar intensity and diffuses incident radiation; generally reducing solar gain and producing soft, natural illumination. The fabric vanes control the amount of light entering the room. Shading devices such as venetian blinds, sheer blinds and drapes have spatially non-uniform and light scattering surfaces. Hence, measurement error occurs if the solar optical properties are measured by traditional narrow-beam measurement techniques typically used in commercial spectrophotometers. To reduce this error, a BAI-IS is recommended. The BAI-IS apparatus consists of a 20-inch diameter integrating sphere, sample mounting system, monochromator, radiant source, lock-in-amplifier, photo sensor, optical chopper and various auxiliary devices. In order to improve reliability of the measurement the BAI-IS has recently been upgraded by replacing most of the key control and measurement equipment. The refurbishment of the BAI-IS apparatus was successful. The directionalhemispherical transmittance of a sheer blind from BAI-IS measurement was found to agree well with an analytical model.

Shading devices are frequently used to control solar gain through windows. Solar optical properties are very important in the energy analysis of windows. Transmittance, absorptance and reflectance are required to quantify solar heat gain through complex fenestration systems, which consist of combinations of glazing and shading layers. In this research the solar transmittance of a sheer blind was measured using a Broad Area Illuminating Integrating Sphere (BAI-IS). More specifically, the spectral directional-hemispherical transmittance was measured in the wavelength range of 0.4 µm to 2.0 µm. A “sheer blind” consists of soft fabric vanes, similar to a venetian blind, suspended between two vertical layers of sheer fabric. This arrangement is popular because it is attractive and it has potential application for daylighting. The vertical sheer fabric reduces the solar intensity and diffuses incident radiation; generally reducing solar gain and producing soft, natural illumination. The fabric vanes control the amount of light entering the room. Shading devices such as venetian blinds, sheer blinds and drapes have spatially non-uniform and light scattering surfaces. Hence, measurement error occurs if the solar optical properties are measured by traditional narrow-beam measurement techniques typically used in commercial spectrophotometers. To reduce this error, a BAI-IS is recommended. The BAI-IS apparatus consists of a 20-inch diameter integrating sphere, sample mounting system, monochromator, radiant source, lock-in-amplifier, photo sensor, optical chopper and various auxiliary devices. In order to improve reliability of the measurement the BAI-IS has recently been upgraded by replacing most of the key control and measurement equipment. The refurbishment of the BAI-IS apparatus was successful. The directionalhemispherical transmittance of a sheer blind from BAI-IS measurement was found to agree well with an analytical model.

This study investigates the emergence of civil society in China. The existence and sustainability of civil society in China has bearing on the countrys further economic, political and social development. Using a mix of qualitative and quantitative methods, this study employs secondary statistical data as well as individual and focus groups interviews to address the emergence of civil society and intellectuals in China. The position of this paper is that Chinese civil society has developed in fits and starts since the beginning of economic liberalization in 1978. This contributed to changes in the political and social spheres, allowing more autonomous bodies to grow out of society as well as state structures, and facilitating the emergence of Chinese civil society. Intellectuals in particular have been able to exercise their autonomy in the Chinese policy process, influencing the direction of state policy towards their own interests, and consequently strengthening the public sphere and civil society.<p> Chinese civil society is punctuated by the influence of the historical, cultural, and political factors that constitute the form of its institutions, organizations and associations, as well as how these social actors communicate in the public sphere. It differs from that generally found in western countries. Unlike the west, it does not exist in opposition to the state. Instead, Chinese institutions of civil society also exist at the interstices between state and society and across them as well. This entwining entanglement of civil society with the state is indicative of the specific social, political, economic, and cultural conditions that have contributed to its development.<p> As it continues to emerge, Chinese civil society is increasingly becoming a sphere of identity formation, social integration, and cultural reproduction.

The birefringence of one-dimension PMMA surface gratings on a gold film substrate is investigated. The grating served as a coupler to facilitate the incoming light coupled to surface plasmon wave (SPW) which possesses high propagation wave vector. Since surface plasmon waves(SPWs) have a special dispersion relation, the birefringence £Gneff (£Gneff =nx-ny, where grating k-vector is along x axis) of this structure is relatively large and can be changed from positive to negative by changing the operation wavelength. The obtained the four Stokes parameters at 515nm and 633nm are marked on the Poincare sphere. £Gneff is 2£k/7 and -£k/8 at 515nm and 633nm respectively. Further, by changing the form factor of PMMA gratings, we found that the maximum £Gneff occurred when PMMA stripe width : air gap=1:1.

The research aims to design an experimental testing mechanism and process for measuring the scattering strength and the pattern induced by an underwater target. The experimental data are to compare with existing theoretical results to insure the integrity of experimental design. The experiment is conducted in a water tank of dimension 4m x 3.5 m x 2m. The main work is to measure the sound field scattered by a copper sphere of diameter 60mm. There are two types of sources employed in this analysis: one is omni-directional, 70kHz CTG-0708 transducer, and the other is directive, 192 kHz iTP-192k transducer. Both transducers transmit sine waves with the pulse lengths roughly equal to 0.143 msec (equivalent to 10 waves) and 0.333 msec (equivalent to 64 waves), respectively. The scattering field theory is based on the formulation developed by Hickling (JASA, 34, 1962, pp.1582-1592). The experimental process has demonstrated that it is more difficult to measure the forward scattering field than the backward scattering field, due to the fact that the forward scattering field is likely to be mingled with the direct waves. To deal with this problem, the treatment developed by L. Ding¡]JASA, 101,1997, pp.3398-3404¡^has been invoked, in that the direct waves may be filtered by phase shift. This procedure requires the special concern on synchronism of sound source in order to avoid the variation of scattering signals. The comparison between experimental and theoretical results shows that the discrepancy in the forward scattering sector is within 3 to 4 dB, while in the backscattering sector, it is within 1 to 2 dB; however, generally speaking, the variation of the curves show a good agreement. These results indicate that the design of this experiment is basically practicable, and with further improvements, it could be applied to measure other underwater targets. As a whole, the thesis is composed by basic theory deduction, experimental instrumentation, mechanism design, and experiment data analysis. The emphases place on the design and observation of the scattering experiment, data analysis, and further improvement.