A two-step multiuser detection scheme for space-time coded MIMO OFDM systems

In this paper, we investigate transceiver design for a wideband multiuser-multiple-input, multiple-output (MIMO) communication system, where the co-channel users are equipped with multiple transmit and multiple receive antennas. In particular, we develop a two-step hard-decision interference cancellation receiver for a multiuser-MIMO uplink system which employs orthogonal frequency division multiplexing (OFDM) modulation and space-time block codes (STBC). The STBC has been implemented either over adjacent tones or adjacent OFDM symbols and the performances of both implementations have been tested under slowly time-varying channels. The two-step receiver structure has been implemented using a combined interference suppression scheme based on minimum mean-squared error (MMSE) and symbol-wise likelihood detectors, which is then followed by an interference cancellation step. The receiver can suppress and cancel the interference from the co-channel users effectively without increasing the complexity significantly. The paper also includes computer experiments that are intended to improve the understanding of specific issues involved in the design of multiuser STBC-OFDM systems

A space-time coded MIMO-OFDM multiuser application with iterative MMSE-decision feedback algorithm

A popular technique for high data rate wireless transmission is OFDM. To increase the diversity gain and/or to enhance the system capacity, in practice, OFDM may be used in combination with antenna arrays at the transmitter and receiver to form a multiple-input multiple-output (MIMO) system. In this paper, an iterative multiuser receiver structure for space-time block coded MIMO OFDM scheme is exploited over slow fading channels. We utilize iterative detection based on minimum mean square error updated with decision feedback (MMSE-DF). The symbols are estimated in iterative process by updating extrinsic information to develop log-likelihood ratios (LLRs). Simulation results indicate that the scheme is proposed for the considered scenario and the performance over classical linear MMSE estimator

Pengaruhmodel Pembelajaran Vak (Visual, Auditori, Kinestetik) Terhadap Kemampuan Menulis Puisi Oleh Siswa Kelas VIII SMP N. 2 Porsea Tahun Pembelajaran 2012/2013

This study aimed to clarify the effect of the learning model VAK (Visual, Auditory,Kinesthetic) the ability to write poetry by the students of class VIII SMP N.2 PorseaLearning Year 2012/2013. The population of this research is all eighth grade studentsas junior N.2 Porsea 266 people. Samples were taken at random as many as 30people.The method used in this study is an experimental method. The instrument usedis the argument essay writing test. The average value of post-test is 75.50, while forthe pre-test is is 67.1. Thus, it can be said that the average value of students\u27 ability towrite poetry after treatment (post-test) higher than before treatment (pre-test).Hypothesis testing is done by using the test "t". Test hypotheses derived from thecalculation of t = 2.95, then consulted with the table t at 5% significance level = 2.04.Since t = 2.95> t = 2.04 nil then the hypothesis (H) is rejected. It is proved that thelearning model VAK (Visual, Auditory, Kinesthetic) affects the ability to writepoetry class VIII SMP Porsea N.2

Design criteria and applications of multi-channel parallel microfluidic module

The microfluidic technology for function microsphere synthesis has high control precision. However, the throughput is too low for industrial scale-up applications. Current scale-up design focuses on a multi-channel in 2D, in which the distribution uniformity parameter δ increases linearly, resulting in the deterioration of the flow distribution performance. The 3D modular scale-up strategy could greatly alleviate this problem, but no design principles have been developed yet. For the first time, this paper establishes the microfluidic 3D scale-up design criteria. Based on the modular design concept, the design method of 2D and 3D throughput scale-up parameters N and M, distribution uniformity parameters δ and β, and microchannel design parameter KRwere proposed. The equivalent resistance coefficient was defined, and the influence of different parameters on a 2D array and 3D stack was analyzed. Furthermore, the error correction method was studied. It was found that the two-stage scale-up process contradicted each other. A good scale-up performance of one stage led to the limitation of another stage. Increasing the resistance of each channel Rucould both increase the two-stage scale-up performance, which was an important factor. A single-module scale-up system with 8 channels in a single array and 10 arrays in a vertical stack, which had 80 channels in total, was designed and fabricated based on the proposed design criteria for generating Chitosan/TiO2composite microspheres. The average particle size was 539.65 μm and CV value was about 3.59%. The throughput was 480 ml h-1, which effectively increased the throughput scale and the product quality

Toward a mechanistic understanding of microfluidic droplet-based extraction and separation of lanthanides

Droplet-based microfluidic extraction is a promising way for effective lanthanides extraction due to its outstanding mass transfer performance. The separation process can be greatly enhanced with the droplet-based microfluidic extraction technique. However, the interactions between mass transfer, microfluidic dynamics and extraction kinetics are still unclear, which has hindered further manipulation on microfluidic extraction to boost extraction performance. In this study, the mechanisms of microfluidic droplet-based extraction and separation intensification of lanthanides are for the first time unveiled by using a numerical simulation model. The limiting factors for the performance of droplet-based microfluidic extraction are identified through a model-based parametric analysis. The numerical analyses provide a comprehensive understanding of droplet-based microfluidic extraction systems and offer operation and optimization guidelines for future research in this area

Kata Ganti Orang Dalam Bahasa Inggris Dan Bahasa Selaru (Suatu Analisis Kontrastif)

This research attempts to identify and classify personal pronouns in English and Selaru language. The data are taken from interviewing some informants (native speakers) who was born in Selaru and understand the language and can interact effectively. The identified data are analyzed according to the concept of Bloomfield and then contrast them by using Lado\u27s concept. In analyzing the data, the writer uses descriptive method. The problems of this research ore focused on what are the personal pronouns in terms of form and function in English and Selaru language and what are the similarities and differences of personal pronouns in terms of form and function in English and Selaru language. The aims of the research are to identify and classify personal pronouns in English and Selaru language and to find out the similarities as well as dissimilarities of personal pronouns in both languages in terms of form and function. The results of this research shows that English and Selaru language has similarities and dissimilarities. Similarities in English and Selaru language which has the form of the first person, second, third, both singular and plural and dissimilarities in English and Selaru language namely: in English has object, possessive pronoun and third person singular neutral,whereas in selaru language not found

Spatial distribution of surround suppression of a sample recording site.

<p>Surround suppression was not always uniform for the firing rate (A) and gLFP (B). In this recording site, both responses had a distinct LSR of similar sizes. These LSRs did not overlap, but were aligned to the optimal direction. The dashed circle indicates the SSF size and position. The dashed arrow indicates the optimal direction of firing rate, which was also the drifting direction of all stimuli. For the sake of illustration, the data were interpolated four times by a 2D third-order spline.</p

Size-tuning responses of a sample recording site.

<p>(A–C) Multi-unit and LFP responses to the enlarging drifting gratings. Black vertical lines indicate the stimulus onset and offset times. The gray horizontal bars indicate the sustained response windows. (D) Size-tuning curve of the sustained response of mean firing rate. The data points indicate the mean ± SE. The solid line is the DoG function fitted from the data, with Adjust-R² = 0.951. The dashed line indicates the response level of uniform background control. (E) LFP power spectrum of different stimulus sizes. The gray bar indicates gamma band. (F) Normalized spike power spectrum of different stimulus sizes. The color code is identical to that of (E). (G) Size-tuning curve of sustained gLFP. The Adjust-R² of the fitted DoG was 0.871. The legends are identical to those of (D).</p

Stimulus paradigm.

<p>(A) Center-surround compound stimulus set. The center orientation selectivity was tested under different surround orientations in each column. The orientation selectivity of surround suppression was tested under different center orientations in each row. Surround orientation was the relative angle to the center orientation. (B) Spatial organization of surround modulation was tested by co-stimulation of grid center and other positions. The center stimulus response was chosen as the control level of surround suppression. See text for details.</p

Population-averaged orientation tuning of surround modulation.

<p>Horizontal lines and shadings indicate the mean ± SE of CRF stimulation without the surround stimulus. The Data points represent the mean ± SE under different surround orientations.</p