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SUMMARYWe propose a novel intercarrier interference (ICI) self-cancellation scheme for orthogonal frequency division multiplexing (OFDM) systems. The symmetric scheme is the best among all ICI self-cancellation scheme in the literature. Its coefficient pair is (1, −1), and the loading subcarriers are the k th and N −k −1 th subcarriers, where N is the number of subcarriers. We propose to modify the symmetric scheme and change the coefficient pair from (1, −1) to (1, − ) where is between 0 and 1. The proposed modified symmetric scheme has better carrier-to-interference-ratio (CIR) than all previous ICI self-cancellation schemes by at least 1.7 dB when the normalized frequency offset is 0.5.

Transport is the lifeblood of a nation's economy. Since the fossil fuels are being gradually depleted and the global warming phenomena are more and more serious, this article is to construct a low-carbon transport infrastructure for Taiwan by the implementation of energy-saving measures. First of all, via data collection and analysis, we found that the small passenger cars and the large trucks are the largest energy users in the transport sector, due to their high energy intensities and large transport volumes. Therefore, their energy-conserving potentials are the focuses of this study. According to "Top-Down" methodology, the most effective and economical energy-saving strategies for Taiwan's transport sector are the significant adoptions of rail transport and electrification mode. Whereby, under a maximal energy-saving scenario, comprising of delicate shift of transport volumes, the energy saving potential in the land transport sector of Taiwan is 4914 MLOE (million liters of oil equivalent), which is equivalent to greenhouse gas reduction of 10.56 Mt-CO 2e approximately with a scale of 45.3% or crediting for 4.1% reduction of national GHG emissions. Finally, we suggest the green transport infrastructure of Taiwan should be mainly comprised of rail transport, electric motorcycles, MRT (Mass Rapid Transit), and EV (Electric Vehicles). 21 by rail transport completely, we suggest the adoption of electric motorcycle should be more feasible and economical, due to the considerations of personal convenience and dense population in Taiwan. AcknowledgementsThis paper is one of the research results of National Science and Technology Program-Energy (NSTPE) sponsored by National Science Council (Taiwan).

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This study deals with the design for manufacturing (DFM) of fractals created by a random walk called iterated function system (IFS). In particular, the DFM of an IFS-created fractal called Barnsley's fern-leaf is considered. The IFS dedicated for creating virtual models of a fern-leaf uses a set of four strictlycontracting affine mappings in the onto manner. The interactions among these mappings are studied in detail in order to identify some data structures. Based on the identified data structures, a DFM procedure is proposed. In the proposed DFM procedure, three out of the four mappings are employed in both the onto and one-to-one manner. The proposed DFM procedure is applied to the redesign of the shape (fern-leaf). Physical models of the redesigned fern-leaf are manufactured using both additive and subtractive manufacturing technologies (3-D printing and milling). The factors affecting accuracy of the physical models are also described. Although this study is limited to the shape of the fern-leaf, other IFS-created shapes can be redesigned using the proposed DFM procedure. Nevertheless, this study sheds some light on our understanding of how to develop more accurate physical models of IFS-created fractals.