The Experts below are selected from a list of 2193 Experts worldwide ranked by ideXlab platform

James L. Drewniak - One of the best experts on this subject based on the ideXlab platform.

  • Directional Antenna With Consistent H-Plane Dual-Band Beamwidth for Wi-Fi Applications
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Yihong Qi, Zi-bin Weng, Wei Yu, Fuhai Li, James L. Drewniak
    Abstract:

    A Wi-Fi dual-band directional antenna is presented herein. The proposed antenna consists of a bent ground-backed slot-loop structure to form a directional antenna. The aperture of the antenna element and the offset from the ground plane have opposing functional variation for the beamwidth adjustment. By utilizing both factors, a consistent Wi-Fi dual-band beamwidth is achieved. The antenna has high radiation efficiency over both bands. The proposed antenna achieves H-plane dual-band beamwidth consistency, which varies within 5° over the two bands. The gain is 9 and 9.5 dBi, respectively, in the 2.4 and 5 GHz bands, and a stable H-plane beamwidth of 66°-71° over the operating bands is achieved. The proposed antenna can be used for the sectorized Wi-Fi access Point Application or as an element to form an array.

P. Samec - One of the best experts on this subject based on the ideXlab platform.

  • The effect of Point Application of fertilizers on the soil environment of spread line windrows in the Krušné hory Mts.
    Journal of forest science, 2018
    Co-Authors: D. Vavříček, J. Pecháček, P. Jonák, P. Samec
    Abstract:

    The plateau of the Krusne hory Mts. belongs to areas that suffered the greatest damage caused by air- pollution stresses in Europe. A part of cultural practices aimed at the reconstruction of local mountain forests was the inconsiderate use of bulldozer technologies for the preparation of sites for forest stand restoration. In the course of large-scale scarification the top-soil horizons were moved into line windrows, which caused marked degradation of the soil environment. The present revitalization of the soil environment is based on the principle of spreading these man- made windrows. Experimental plots were established in localities affected by scarification; the organomineral material from windrows was superimposed on them and subsequently they were reforested with Norway spruce ( Picea abies (L.) Karst.). In 2005 the Point Application of fertilizer tablets of Silvamix type in three treatments and calcic dolomite was performed into the rhizosphere of plants. Before fertilization and after three years of the experiment soil samples were taken from the organomineral zone of the root balls of plants, and the condition of the soil environment on spread windrows and changes in pedochemical properties as a result of applied fertilization were evaluated. Three years after the windrow spreading the content of the majority of soil macrobiogenic elements (N, K, Ca, Mg) is at the level of me - dium-high to high reserves, and only the low phosphorus reserves pose a certain hazard. The organomineral substrate of spread windrows is a suitable growth environment for the root systems of target tree species. The proportion of humus substances is the most important factor in spread windrows from which the characteristics of the other parameters of soil are derived. Along with the higher proportion of humus substances in Spicak locality significantly higher reserves of major macrobiogenic elements (N, P, K, Ca, Mg) were determined. The applied fertilizers of Silvamix type signifi - cantly increased the reserves of soil P, K, Ca, Mg and are a suitable means for the stimulation of spruce plantations in the restored environment of the Krusne hory Mts. Silvamix Forte fertilizer tablets are the most complex fertilizer with the most balanced effects that significantly increases the reserves of soil P, Mg and K. This fertilizer has a high effect on an increase in the reserves of soil phosphorus that may be deficient in conditions of spread windrows. Silvamix R is the most efficient fertilizer to increase potassium reserves. A positive effect of calcic dolomite on an increase in Ca and Mg content was observed while no such effect on the other elements was recorded.

  • The effect of Point Application of fertilizerson the soil environment of spread line windrows in the Krušné hory Mts
    Journal of Forest Science, 2010
    Co-Authors: D. Vavříček, J. Pecháček, P. Jonák, P. Samec
    Abstract:

    The plateau of the Krušné hory Mts. belongs to areas that suffered the greatest damage caused by air-pollution stresses in Europe. A part of cultural practices aimed at the reconstruction of local mountain forests was the inconsiderate use of bulldozer technologies for the preparation of sites for forest stand restoration. In the course of large-scale scarification the top-soil horizons were moved into line windrows, which caused marked degradation of the soil environment. The present revitalization of the soil environment is based on the principle of spreading these man-made windrows. Experimental plots were established in localities affected by scarification; the organomineral material from windrows was superimposed on them and subsequently they were reforested with Norway spruce (Picea abies [L.] Karst.). In 2005 the Point Application of fertilizer tablets of Silvamix type in three treatments and calcic dolomite was performed into the rhizosphere of plants. Before fertilization and after three years of the experiment soil samples were taken from the organomineral zone of the root balls of plants, and the condition of the soil environment on spread windrows and changes in pedochemical properties as a result of applied fertilization were evaluated. Three years after the windrow spreading the content of the majority of soil macrobiogenic elements (N, K, Ca, Mg) is at the level of medium-high to high reserves, and only the low phosphorus reserves pose a certain hazard. The organomineral substrate of spread windrows is a suitable growth environment for the root systems of target tree species. The proportion of humus substances is the most important factor in spread windrows from which the characteristics of the other parameters of soil are derived. Along with the higher proportion of humus substances in Špičák locality significantly higher reserves of major macrobiogenic elements (N, P, K, Ca, Mg) were determined. The applied fertilizers of Silvamix type significantly increased the reserves of soil P, K, Ca, Mg and are a suitable means for the stimulation of spruce plantations in the restored environment of the Krušné hory Mts. Silvamix Forte fertilizer tablets are the most complex fertilizer with the most balanced effects that significantly increases the reserves of soil P, Mg and K. This fertilizer has a high effect on an increase in the reserves of soil phosphorus that may be deficient in conditions of spread windrows. Silvamix R is the most efficient fertilizer to increase potassium reserves. A positive effect of calcic dolomite on an increase in Ca and Mg content was observed while no such effect on the other elements was recorded.  

Xiangshui Miao - One of the best experts on this subject based on the ideXlab platform.

  • Nb1-xO2 based Universal Selector with Ultra-high Endurance (>1012), high speed (10ns) and Excellent Vth Stability
    2019 Symposium on VLSI Technology, 2019
    Co-Authors: Jie Yu, Xumeng Zhang, Jun-hui Yuan, Yan Cheng, Tiancheng Gong, Hangbing Lv, Xiaoxin Xu, Peng Yuan, Shibing Long, Xiangshui Miao
    Abstract:

    In this work, we demonstrate a high performance Nb1-xO2 based selector with thermal feedback mechanism for 3D X-Point Application. Ultra-high endurance , high operation speed (10ns), bidirectional operation and excellent Vth stability were achieved. By adding a barrier layer between Nb1-xO2 film and electrode, the off-state leakage current was reduced by one order of magnitude (selectivity as high as 500). This work provides a universal selector solution for various emerging memories, including RRAM, MRAM and PCM.

  • Ultra-Low Program Current and Multilevel Phase Change Memory for High-Density Storage Achieved by a Low-Current SET Pre-Operation
    IEEE Electron Device Letters, 2019
    Co-Authors: Mingze He, Da He, Hang Qian, Xiaomin Cheng, Ming Xu, Hao Tong, Xiangshui Miao
    Abstract:

    We have fabricated a pillar structure phase change memory (PCM) with the prototypical phase change material Ge2Sb2Te5. Using a Low Current SET (LCS) pre-operation, the devices can operate with an ultralow RESET current density and have multilevel cell (MLC) capability, and these features both contribute to high storage density. Specifically, the RESET current density is only 4.84 MA/cm2, which is lowest among all the CMOS compatible PCM devices, and this ultra-low RESET current density enables the possibility to link with a two-terminal selector for 3D cross-Point Application. Meanwhile LCS makes MLC operation of our PCM more stable with a low operating current. In summary, this LCS pre-operation can greatly increase the storage density both by enabling integration with selectors for 3D cross-Point and by stabilizing MLC operation when maintaining the feature size of PCM devices.

Yihong Qi - One of the best experts on this subject based on the ideXlab platform.

  • Directional Antenna With Consistent H-Plane Dual-Band Beamwidth for Wi-Fi Applications
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Yihong Qi, Zi-bin Weng, Wei Yu, Fuhai Li, James L. Drewniak
    Abstract:

    A Wi-Fi dual-band directional antenna is presented herein. The proposed antenna consists of a bent ground-backed slot-loop structure to form a directional antenna. The aperture of the antenna element and the offset from the ground plane have opposing functional variation for the beamwidth adjustment. By utilizing both factors, a consistent Wi-Fi dual-band beamwidth is achieved. The antenna has high radiation efficiency over both bands. The proposed antenna achieves H-plane dual-band beamwidth consistency, which varies within 5° over the two bands. The gain is 9 and 9.5 dBi, respectively, in the 2.4 and 5 GHz bands, and a stable H-plane beamwidth of 66°-71° over the operating bands is achieved. The proposed antenna can be used for the sectorized Wi-Fi access Point Application or as an element to form an array.

D. Vavříček - One of the best experts on this subject based on the ideXlab platform.

  • The effect of Point Application of fertilizers on the soil environment of spread line windrows in the Krušné hory Mts.
    Journal of forest science, 2018
    Co-Authors: D. Vavříček, J. Pecháček, P. Jonák, P. Samec
    Abstract:

    The plateau of the Krusne hory Mts. belongs to areas that suffered the greatest damage caused by air- pollution stresses in Europe. A part of cultural practices aimed at the reconstruction of local mountain forests was the inconsiderate use of bulldozer technologies for the preparation of sites for forest stand restoration. In the course of large-scale scarification the top-soil horizons were moved into line windrows, which caused marked degradation of the soil environment. The present revitalization of the soil environment is based on the principle of spreading these man- made windrows. Experimental plots were established in localities affected by scarification; the organomineral material from windrows was superimposed on them and subsequently they were reforested with Norway spruce ( Picea abies (L.) Karst.). In 2005 the Point Application of fertilizer tablets of Silvamix type in three treatments and calcic dolomite was performed into the rhizosphere of plants. Before fertilization and after three years of the experiment soil samples were taken from the organomineral zone of the root balls of plants, and the condition of the soil environment on spread windrows and changes in pedochemical properties as a result of applied fertilization were evaluated. Three years after the windrow spreading the content of the majority of soil macrobiogenic elements (N, K, Ca, Mg) is at the level of me - dium-high to high reserves, and only the low phosphorus reserves pose a certain hazard. The organomineral substrate of spread windrows is a suitable growth environment for the root systems of target tree species. The proportion of humus substances is the most important factor in spread windrows from which the characteristics of the other parameters of soil are derived. Along with the higher proportion of humus substances in Spicak locality significantly higher reserves of major macrobiogenic elements (N, P, K, Ca, Mg) were determined. The applied fertilizers of Silvamix type signifi - cantly increased the reserves of soil P, K, Ca, Mg and are a suitable means for the stimulation of spruce plantations in the restored environment of the Krusne hory Mts. Silvamix Forte fertilizer tablets are the most complex fertilizer with the most balanced effects that significantly increases the reserves of soil P, Mg and K. This fertilizer has a high effect on an increase in the reserves of soil phosphorus that may be deficient in conditions of spread windrows. Silvamix R is the most efficient fertilizer to increase potassium reserves. A positive effect of calcic dolomite on an increase in Ca and Mg content was observed while no such effect on the other elements was recorded.

  • The effect of Point Application of fertilizerson the soil environment of spread line windrows in the Krušné hory Mts
    Journal of Forest Science, 2010
    Co-Authors: D. Vavříček, J. Pecháček, P. Jonák, P. Samec
    Abstract:

    The plateau of the Krušné hory Mts. belongs to areas that suffered the greatest damage caused by air-pollution stresses in Europe. A part of cultural practices aimed at the reconstruction of local mountain forests was the inconsiderate use of bulldozer technologies for the preparation of sites for forest stand restoration. In the course of large-scale scarification the top-soil horizons were moved into line windrows, which caused marked degradation of the soil environment. The present revitalization of the soil environment is based on the principle of spreading these man-made windrows. Experimental plots were established in localities affected by scarification; the organomineral material from windrows was superimposed on them and subsequently they were reforested with Norway spruce (Picea abies [L.] Karst.). In 2005 the Point Application of fertilizer tablets of Silvamix type in three treatments and calcic dolomite was performed into the rhizosphere of plants. Before fertilization and after three years of the experiment soil samples were taken from the organomineral zone of the root balls of plants, and the condition of the soil environment on spread windrows and changes in pedochemical properties as a result of applied fertilization were evaluated. Three years after the windrow spreading the content of the majority of soil macrobiogenic elements (N, K, Ca, Mg) is at the level of medium-high to high reserves, and only the low phosphorus reserves pose a certain hazard. The organomineral substrate of spread windrows is a suitable growth environment for the root systems of target tree species. The proportion of humus substances is the most important factor in spread windrows from which the characteristics of the other parameters of soil are derived. Along with the higher proportion of humus substances in Špičák locality significantly higher reserves of major macrobiogenic elements (N, P, K, Ca, Mg) were determined. The applied fertilizers of Silvamix type significantly increased the reserves of soil P, K, Ca, Mg and are a suitable means for the stimulation of spruce plantations in the restored environment of the Krušné hory Mts. Silvamix Forte fertilizer tablets are the most complex fertilizer with the most balanced effects that significantly increases the reserves of soil P, Mg and K. This fertilizer has a high effect on an increase in the reserves of soil phosphorus that may be deficient in conditions of spread windrows. Silvamix R is the most efficient fertilizer to increase potassium reserves. A positive effect of calcic dolomite on an increase in Ca and Mg content was observed while no such effect on the other elements was recorded.