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Identification of environmental factors that strongly influence growth indicators (diameter at breast height, tree height and carbon density) for Larix gmelinii forests in the cold-temperate zone on the Greater Khingan Mountains, northeast China will provide an important reference for sustainable management of the forests. In this study, 75 plots were established in L. gmelinii forests during a forest inventory from 2015 to 2022. Sixteen environmental predictors, comprising climatic, edaphic, topographic, and biotic factors, were selected according to their ecological importance for L. gmelinii forests and peer-reviewed literature to determine their influence on the growth of L. gmelinii forests using linear fitting and redundancy analysis. Stocking degree had the strongest significant correlation with carbon density in the tree layer, which increased with increasing stocking degree. Solar radiation had the strongest significant positive correlation with stand average diameter at breast height. The stand average height was most strongly correlated with soil organic carbon content, with which it had a significant positive correlation. Stocking degree, solar radiation and soil organic carbon content were the dominant factors affecting the growth of L. gmelinii forests. Forest management should incorporate improved light and soil conditions and increase the stocking degree to promote growth of L. gmelinii forests. [ABSTRACT FROM AUTHOR]

To test an integrated circuit (IC) product, both a tester and qualified kits are simultaneously needed. One kit usually consists of six or seven components and is somewhat like a fixture. A remarkable amount of investment will be saved if one allows kit reconfigurations and purchase individual components instead of using entire kits. Unfortunately, this approach of the reconfigurable kit also increase exponentially the complexity of kit management and thus capacity planning due to intricate {product, tester, kit, component} qualification relationships. The paper describes the Automated Capacity Allocation System (ACAS) developed at Intel Shanghai for generating an optimal capacity and kit-allocation plan for a 9-week horizon. It performs optimization at the component level using Mixed-Integer Programming (MIP) technology. High Buffer Formulation and Tight Workload Formulation are introduced to determine the number of kits needed to guarantee a feasible capacity plan. Detailed analyses of parameter setting, objective prioritizing and formulation comparison were also conducted. With the implementation of the ACAS at Intel, we have already realized millions of dollars in savings from kit purchasing and about 90% man-hour savings in the capacity planning. [ABSTRACT FROM AUTHOR]

The spatial patterns and associations of adjacent tree species among the vertical layers of a forest were analysed with point-pattern statistics (a pair-correlation function) in a 1-ha plot. The hierarchy of tree species from highest to lowest importance values (IVs) was as follows: A. nephrolepis, P. jezoensis, P. koraiensis, and T. amurensis. All trees with a diameter at breast height (DBH) >1.0 cm were identified. (1) Clustered distributions were observed at fine scales for some tree species, possibly caused by environmental heterogeneity, limited seed dispersal or biological characteristics of seeds; however, random or even regular distributions indicated a "self-thinning" process with intra-specific competition. (2) It was also found positive associations at small scales among species pairs in different tree-height classes that might be a function of the shade-tolerance of congeners, different niches or the influence of habitat heterogeneity on niche breadth, whereas significant negative associations at large scales might be caused by adverse anthropogenic interference or existing habitat heterogeneity. (3) Additionally, habitat heterogeneity, limited seed dispersal and inter-specific competition might be the most important factors that influence species spatial patterns and associations; these scenarios can provide new insight into the development of reforestation practices in forest management. [ABSTRACT FROM AUTHOR]

This paper presents a Ku-band dual-polarized patch unit-cell of continuous phase shift for reconfigurable reflectarray antennas, which can twist the polarization of incident wave. This cross-polarized unit-cell can be applied in the folded reflectarray configuration for beam-scanning, and its performance is validated by the full-wave simulations under periodic boundary conditions. The scattered phase of the cross-polarized field varies continuously by approximate 300° as the capacitance in the varactor diodes is varied, and the magnitude of the cross-polarized field is higher than that of co-polarized field. The calculated results confirm that the dual-polarized multi-layer unit-cell consisting of dual-polarized H-shaped aperture coupled microstrips and vararctor-based reflection-type phase-shifter can be used as a reconfigurable reflectarray unit-cell to reflect the incident wave with a continuous phase shift after polarization twist. [ABSTRACT FROM AUTHOR]

A compact structure is proposed to realize dual circularly polarized antenna for RFID system. In this paper, a cross-shaped aperture in the ground plane provides coupling between the patch and a single microstrip line with two ports underneath the ground plane, the means of feeding is constructed. For system requirements, some modifications are made to improve the performance. This design realizes low profile, separating the radiating patch and the feeding layer, particularly saving space by avoiding the traditional scheme based on microstrip branch line coupler. In the wireless communication system for RFID applications, circular polarization modulation (CPM) is implemented, which reduces the requirement for bandwidth effectively, and simplifies the data communication. Therefore, a dual circularly polarized antenna is an indispensable key part of this RFID system, and in some case the compact structure is necessary. In this design process, the dimensions and performance of this antenna are calculated and optimized by HFSS (High Frequency Structure Simulator). The results agree well with the measurement, and show the practicability of this scheme. [ABSTRACT FROM AUTHOR]

A folded slot with open end is introduced to achieve a dual-band coplanar waveguide (CPW)-fed monopole antenna for radio frequency identification (RFID) applications. The designed antenna, which, including the substrate, is only 32 mm in height and 20 mm in width, can operate simultaneously at the 2.45 and 5.8 GHz bands with -1.8 and 2.3 dBi gains, respectively. Its properties make the antenna suitable for RFID tags. [ABSTRACT FROM AUTHOR]