There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

OUTPU T 29 OUTPU T 30 OUTPU T 31 OUTPU T 32 OUTPU T 25 OUTPU T 26 OUTPU T 27 OUTPU T 28 OUTPU T 21 OUTPU T 22 OUTPU T 23 OUTPU T 24 OUTPU T 17 OUTPU T 18 OUTPU T 19 OUTPU T 20 OUTPU T 13 OUTPU T 14 OUTPU T 15 OUTPU T 16 OUTPU T 9 OUTPU T 10 OUTPU T 11 OUTPU T 12 OUTPU T 5 OUTPU T 6 OUTPU T 7 OUTPU T 8 OUTPU T 1 OUTPU T 2 OUTPU T 3 OUTPU T 4 29 30 31 32 25 26 27 28 21 22 23 24 17 18 19 20 13 14 15 16 9

A User’s Guide

Come with us to read a new book that is coming recently. Yeah, this is a new coming book that many people really want to read will you be one of them? Of course, you should be. It will not make you feel so hard to enjoy your life. Even some people think that reading is a hard to do, you must be sure that you can do it. Hard will be felt when you have no ideas about what kind of book to read. Or sometimes, your reading material is not interesting enough.

Design Of Integrated Circuits For Optical Communications

LTE-Advanced (Release 10) is a preliminary mobile communication standard formally submitted as a candidate 4G systems to the ITU-T. It is being standardized by the 3rd Generation Partnership Project (3GPP) as a major enhancement of the 3GPP Long Term Evolution (LTE-Release 8) standard, which proved to be sufficient to satisfy market's demand. The 3GPP group has been working on different aspects to improve LTE performance, where the purpose of the framework provided by LTE-Advanced, includes higher order MIMO, carrier aggregation (carriers with multiple components), and heterogeneous networks (relays, picos). This paper presents a study on evolution LTE toward LTE-Advanced in terms of LTE enabling technologies (Orthogonal Frequency Division Multiplexing (OFDM) and Multiple-Input Multiple-Output (MIMO)). This paper also focuses on LTE-Advanced technologies MIMO enhancements for LTE-Advanced, Coordinated Multi Point transmission (CoMP), repeaters and relays.

Performance of LTE Release 8 and Release 10 in wireless communications

LTE-Advanced (Long Term Evolution-Advanced) is used on fourth generation (4G) in mobile phone technology as many providers are beginning to augment their networks with LTE. As known, mobile phone tra-c is divided into two parts: an uplink and a downlink. This paper presents the LTE two duplexing modes: LTE-TDD (Time Division Duplexing) and LTE-FDD (Frequency Division Duplexing). Where LTE-TDD favored by a majority of implementations because of ∞exibility in choosing uplink to downlink data rate ratios, ability to exploit channel reciprocity, ability to implement in non-paired spectrum and less complex transceiver design. In the case of FDD operation there are two carrier frequencies, one for uplink transmission (fUL) and one for downlink transmission ( fDL). During each frame, there are thus ten uplink subframes and ten downlink subframes, so uplink and downlink transmission can occur simultaneously within a cell. LTE-FDD implies that downlink and uplink transmission take place in difierent, su-ciently separated, frequency bands, while TDD implies that downlink and uplink transmission take place in difierent, non overlapping time slots. Thus, TDD can operate in unpaired spectrum, whereas FDD requires paired spectrum. Also the required ∞exibility and resulting requirements to support LTE operation in difierent paired and unpaired frequency arrangements are discussed in this Paper. This paper focuses on the main difierence between LTE-FDD and LTE-TDD in how they divide the single channel to provide paths for both uploading (mobile transmit) and downloading (base-station transmit). FDD does this by dividing the frequency band allotted into two discrete smaller channels. TDD uses the entire channel but alternates between uploading and downloading and in the case of TDD uplink and downlink communication taking place in the same frequency band but in separate non-overlapping time slots; there is typically a high fading correlation between the downlink and uplink. With full coverage in the 3 GPP Release 8 speciflcations of both TDD and FDD modes of operation, LTE can efiectively be deployed in both the paired and unpaired spectrum. LTE TDD and FDD modes have been greatly harmonized in the sense that both modes share the same underlying framework, including radio access schemes OFDMA in downlink and SC-FDMA in uplink, basic subframe formats, conflguration protocols, etc.. As clear indication of the harmonization, the TDD mode is included together with the FDD mode in the same set of speciflcations, including the physical layer where there are just a few difierences due to the uplink/downlink switching operation. In terms of architecture there are no difierences between FDD and TDD and the very few difierences in the MAC and higher layer protocols relate to TDD speciflc physical layer parameters. Procedures are kept the same. Thus there will be high implementation synergies between the two modes allowing for e-cient support of both TDD and FDD in the same network or user device. Coexistence would of course still require careful analysis. Another key feature of the LTE-TDD mode (known also as TD-LTE) is the commonality with TD-SCDMA. In this paper, the detailed aspects of LTE-TDD that difier from the LTE-FDD mode are introduced. Further, information related to both the link and system performance of the LTE TDD mode of operation is given (1).

LTE-FDD and LTE-TDD for Cellular Communications

The initial release of LTE provided extensive support for deployment in spectrum allocations of various characteristics, with bandwidth ranging roughly from 1.3 MHz up to 20 MHz in both paired and unpaired bands. In LTE release 10 the transmission bandwidth can be further extended by means of so-called Carrier Aggregation (CA), where multiple component carriers are aggregated and jointly used for transmission to/from a single terminal. There are up to five component carriers, possibly each of different bandwidth, which can be aggregated, allowing for transmission bandwidth up to 100 MHz backwards compatibility where, each component carrier (CC) uses the release-8 structure. Hence, to a release-8/9 terminal, each CC will appear as an LTE release-8 carrier, while a carrieraggregation capable terminal can exploit the total aggregated bandwidth, enabling higher data rates. In general case, a different number of component carriers can be aggregated for the downlink and uplink. Therefore, this paper highlights the carrier aggregation which supports the inter-band aggregation contiguous component carriers, intra-band aggregation non-contiguous component carriers and inter-band aggregation. This paper also presents the enhancement of LTE spectrum flexibility through carrier aggregation, further extension of multi-antenna transmission and provision of improvements in the area of inter-cell interference coordination in heterogeneous network deployments.

Effective Carrier Aggregation on the LTE-Advanced Systems

The fabrication and characterization of composite films of graphite/bioepoxy is disclosed. Thin films of ~0.1 mm thick are prepared using a simple solution mixing with mass proportion of 1/0.5 (biomonomer/Methylene Diphenyl Diisocyanate, MDI), upon differ treated graphite weight loading (5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 25 wt.%, 30 wt.%) and drop casting at room temperature. The morphologic study by FE-SEM shows a homogeneously dispersed and strong interface between the graphite and the bioepoxy material. Ultraviolet-visible (UV-vis) spectrophotometer are performed to evaluate the changes in adsorption spectra arising with the increasing of graphite weight loading (wt.%) into the bio-based matrix. An eye opening I-V characteristic of the thin films where the percolation threshold occurs at higher graphite loading (20 wt.%, 25 wt.% and 30 wt.%) gives conductivity of 103-104 S/m. Whilst lower graphite loading (5 wt.%, 10 wt.% and 15 wt.%) somehow need further discussion. The influence of graphite in bioepoxy materials is paramount as it across insulatingsemiconductor-conductor applications.

Interconnected interface enhanced electrical properties of graphite in bio-based epoxy from insulating to conductor composites

 —White LEDs Visible Light Communication (VLC) is applied in communication and illumination simultaneously. It provides unrestrained frequency spectrum and a large bandwidth that produces a higher transmission rate and speed in short-range communication. Also, VLC was considered as a promising alternative technology to the radio frequency in the next generation of communication systems. In this paper, the optical attocells configuration and LEDs distribution are proposed for optimizing the received power and Signal-to-Noise Ratio (SNR) in the Line of Sight (LOS) propagation link. Besides that, the trade-off between minimum SNR and received power are investigated. The simulation results showed that the proposed model can save 6.25% of the total transmitted power, and the optical received power versus semi-angle and field of view have with about increased 16.5% and 27.54% respectively. Moreover, the SNR also has 7.4% improvement. Hence, the proposed configuration model has improved the performance of VLC systems and has widen the window for future improvement.

/pdf/optimization-of-received-power-and-snr-for-an-indoor-28pb7wbj8o.pdf

Mohammad Faiz Liew Abdullah

Papers

Performance of LTE Release 8 and Release 10 in wireless communications

LTE-FDD and LTE-TDD for Cellular Communications

Effective Carrier Aggregation on the LTE-Advanced Systems

Interconnected interface enhanced electrical properties of graphite in bio-based epoxy from insulating to conductor composites

Optimization of Received Power and SNR for an Indoor Attocells Network in Visible Light Communication