Resource allocation in multiuser cooperative OFDM system using forced cost based decisions

A sub optimal resource allocation algorithm for Orthogonal Frequency Division Multiplexing (OFDM) based cooperative scheme is proposed. The system consists of multiple relays. Subcarrier space is divided into blocks and relays participating in cooperation are allocated specific blocks to be used with a user. To ensure unique subcarrier assignment system is constrained such that same block cannot be used by more than one user. Users are given fair block assignments while no restriction for maximum number of blocks a relay can employ is given. Forced cost based decisions [1] are used for block allocation. Simulation results show that this scheme outperforms a non cooperating scheme with sequential allocation with respect to power usage.

Fusion or non fusion of coral fragments in Acropora

Corals inhabit high energy environments where frequent disturbances result in physical damage to coralla, including fragmentation, as well as generating and mobilizing large sediment clasts. The branching growth form common in the Acropora genus makes it particularly susceptible to such disturbances and therefore useful for study of the fate of large sediment clasts. Living Acropora samples with natural, extraneous, broken coral branches incorporated on their living surface and dead Acropora skeletons containing embedded clasts of isolated branch sections of Acropora were observed and/or collected from the reef flat of Heron Reef, southern Great Barrier Reef and Bargara, Australia respectively. Here we report three different outcomes when pebble-sized coral branches became lodged on living coral colonies during sedimentation events in natural settings in Acropora: 1) Where live coral branches produced during a disturbance event come to rest on probable genetic clone-mate colonies they become rapidly stabilised leading to complete soft tissue and skeletal fusion; 2) Where the branch and underlying colony are not clone-mates, but may still be the same or similar species, the branches still may be stabilised rapidly by soft tissue, but then one species will overgrow the other; and 3) Where branches represent dead skeletal debris, they are treated like any foreign clast and are surrounded by clypeotheca and incorporated into the corallum by overgrowth. The retention of branch fragments on colonies in high energy reef flat settings may suggest an active role of coral polyps to recognise and fuse with each other. Also, in all cases the healing of disturbed tissue and subsequent skeletal growth is an adaptation important for protecting colonies from invasion by parasites and other benthos following disturbance events and may also serve to increase corallum strength. Knowledge of such adaptations is important in studies of coral behaviour during periods of environmental stress.

A new legal avenue for pricing GHG emissions? To trade or to tax?

In a September 2010 media release the Prime Minister of Australia presented the terms of reference for the newly established Multi-Party Climate Change Committee. Although the Committee is charged with considering climate change mitigation measures in general, specifically the Committee must consider an appropriate mechanism for the establishment of a carbon price. The purpose of this article is to provide an overview of the mechanisms to be considered by the Climate Change Committee, including the use of emissions trading and carbon levies in other jurisdictions. This article argues that for any effective investigation of a carbon price for Australia to occur, a thorough knowledge of other jurisdictions’ methods for carbon pricing is essential.

Daylighting performance of subtropical multi-residential towers : simulations tools for design decisions

During an intensive design-led workshop multidisciplinary design teams examined options for a sustainable multi-residential tower on an inner urban site in Brisbane (Australia). The main aim was to demonstrate the key principles of daylight to every habitable room and cross-ventilation to every apartment in the subtropical climate while responding to acceptable yield and price points. The four conceptual design proposals demonstrated a wide range of outcomes, with buildings ranging from 15 to 30 storeys. Daylight Factor (DF), view to the outside, and the avoidance of direct sunlight were the only quantitative and qualitative performance metrics used to implement daylighting to the proposed buildings during the charrette. This paper further assesses the daylighting performance of the four conceptual designs by utilizing Climate-based daylight modeling (CBDM), specifically Daylight Autonomy (DA) and Useful Daylight Illuminance (UDI). Results show that UDI 100-2000lux calculations provide more useful information on the daylighting design than DF. The percentage of the space with a UDI <100-2000lux larger than 50% ranged from 77% to 86% of the time for active occupant behaviour (occupancy from 6am to 6pm). The paper also highlights the architectural features that mostly affect daylighting design in subtropical climates.

Bariatric surgery or medicine for type 2 diabetes?

Diet and medical treatment are the standard treatment for type 2 diabetes. In obese subjects with type 2 diabetes, bariatric surgery is effective in resolving diabetes. Two clinical trials comparing bariatric surgery to medical treatment were evaluated. Both the Surgical Treatment And Medications Potentially Eradicate Diabetes Efficiently (STAMPEDE) trial (laparoscopic Roux-En Y gastric bypass and sleeve gastrectomy) and the DIet and medical therapy versus BAriatric SurgerY in type 2 diabetes (DIBASY) trial (laparoscopic gastric bypass and biliopancreatic-diversion) showed that surgery was more effective than medical care in resolving or managing type 2 diabetes. Larger studies, or a compilation of studies, are needed to determine whether one of these procedures is better, or if they are all similarly effective, and this should also be weighed against the risk of the operations.

Larger or broader : performance implications of size and diversity of the knowledge worker's egocentric network. [更多或更广：知识员工个人中心网络大小和 多样性对绩效的影响]

Management scholars and practitioners emphasize the importance of the size and diversity of a knowledge worker's social network. Constraints on knowledge workers’ time and energy suggest that more is not always better. Further, why and how larger networks contribute to valuable outcomes deserves further understanding. In this study, we offer hypotheses to shed insight on the question of the diminishing returns of large networks and the specific form of network diversity that may contribute to innovative performance among knowledge workers. We tested our hypotheses using data collected from 93 R&D engineers in a Sino-German automobile electronics company located in China. Study findings identified an inflection point, confirming our hypothesis that the size of the knowledge worker's egocentric network has an inverted U-shaped effect on job performance. We further demonstrate that network dispersion richness (the number of cohorts that the focal employee has connections to) rather than network dispersion evenness (equal distribution of ties across the cohorts) has more influence on the knowledge worker's job performance. Additionally, we found that the curvilinear effect of network size is fully mediated by network dispersion richness. Implications for future research on social networks in China and Western contexts are discussed.

Potentials of social media for tacit knowledge sharing amongst physicians : preliminary findings

Tacit knowledge sharing amongst physicians, such as the sharing of clinical experiences, skills, or know-how, or know-whom, is known to have a significant impact on the quality of medical diagnosis and decisions. This paper posits that social media can provide new opportunities for tacit knowledge sharing amongst physicians, and demonstrates this by presenting findings from a review of relevant literature and a survey conducted with physicians. Semi-structured interviews were conducted with ten physicians from around the world who were active users of social media. Initial thematic analysis revealed eight themes as potential contributions of social web tools to facilitate tacit knowledge flow amongst physicians. The emergent themes are defined, linked to the literature, and supported by instances of interview transcripts. Findings presented here are preliminary, and final results will be reported after accomplishing all phases of data collection and analysis.