In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and imp...In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and implemented. First, an improved algorithm of a multi-resolution file-pyramid construction which is used for the organization of massive image data is presented. Then, a strategy, adopting technologies such as view-dependent levels of detail, target-tiles quick search and tiles seamless connection, is presented for fast scheduling and viewing of images. The results show that compared with the solution of multi-scale image representations based on wavelet, the proposed solution can improve the rendering speed, and the rendering speed does not depend on the image size, though it increases some data storage space. And the proposed solution is suitable for embedded devices and friendly experience.展开更多
Measuring the growth parameters of Ge quantum dots （QDs） embedded in SiO2/Si hetero-structure is pre- requisite for developing the optoelectronic devices such as photovoltaics and sensors. Their optical properties c...Measuring the growth parameters of Ge quantum dots （QDs） embedded in SiO2/Si hetero-structure is pre- requisite for developing the optoelectronic devices such as photovoltaics and sensors. Their optical properties can be tuned by tailoring the growth morphology and structures, where the growth parameters＇ optimizations still need to be explored. We determine the effect of annealing temperature on surface morphology, structures and optical properties of Ge//SiO2//Si hetero-structure. Samples are grown via rf magnetron sputtering and subsequent characterizations are made using imaging and spectroscopic techniques.展开更多
In this paper,we first propose a hidden rule among the secure message,the initial tensor product of two Bell states and the final tensor product when respectively applying local unitary transformations to the first pa...In this paper,we first propose a hidden rule among the secure message,the initial tensor product of two Bell states and the final tensor product when respectively applying local unitary transformations to the first particle of the two initial Bell states,and then present a high-efficiency quantum steganography protocol under the control of the hidden rule.In the proposed quantum steganography scheme,a hidden channel is established to transfer a secret message within any quantum secure direct communication(QSDC) scheme that is based on 2-level quantum states and unitary transformations.The secret message hiding/unhiding process is linked with the QSDC process only by unitary transformations.To accurately describe the capacity of a steganography scheme,a quantitative measure,named embedding efficiency,is introduced in this paper.The performance analysis shows that the proposed steganography scheme achieves a high efficiency as well as a good imperceptibility.Moreover,it is shown that this scheme can resist all serious attacks including the intercept-resend attack,measurement-resend attack,auxiliary particle attack and even the Denial of Service attack.To improve the efficiency of the proposed scheme,the hidden rule is extended based on the tensor product of multiple Bell states.展开更多
For a large-scale array,its realized gain is always smaller than the summation of the element gains in isolation,which is the well-known gain paradox proposed by Hannan.To explain the paradox,embedded element efficien...For a large-scale array,its realized gain is always smaller than the summation of the element gains in isolation,which is the well-known gain paradox proposed by Hannan.To explain the paradox,embedded element efficiency(EEE)was defined to indicate whether the array elements are being fully utilized,and Hannan’s limit was introduced to provide a fundamental upper bound of the EEE.In this paper,Hannan’s limit is extended to assess the beam-scanning capability of a phased array,which can provide a fundamental upper bound of the EEE corresponding to different scanning angles.In addition,the methods for enhancing the EEE of a large-scale array to approach Hannan’s limit are discussed,including selecting an appropriate power pattern for the array element and efficiently decoupling the array elements.For verification,a planar large-scale wide-angle scanning array utilizing a hybrid decoupling strategy is designed in this paper.The proposed decoupling structure improves the isolation between adjacent array elements in both the E-plane and H-plane by approximately 18.3 dB.The beam-scanning range in the E-plane and H-plane can±65°±60°reach and.During beam scanning,the realized gain of the array can be improved by approximately 0.74 dB.After decoup-×ling,the EEE of the 88 wide-angle scanning array can be improved by approximately 12.64%on average during beam scanning,which is closer to Hannan’s limit.展开更多
基金The National Public Benefit Research Foundation of China (No. 201111013-02)
文摘In order to resolve the conflict between the limited resources of embedded devices and the growing amount of massive image data to be shown, a solution for fast images rendering in embedded devices is proposed and implemented. First, an improved algorithm of a multi-resolution file-pyramid construction which is used for the organization of massive image data is presented. Then, a strategy, adopting technologies such as view-dependent levels of detail, target-tiles quick search and tiles seamless connection, is presented for fast scheduling and viewing of images. The results show that compared with the solution of multi-scale image representations based on wavelet, the proposed solution can improve the rendering speed, and the rendering speed does not depend on the image size, though it increases some data storage space. And the proposed solution is suitable for embedded devices and friendly experience.
基金Supported by the Advanced Membrane Technology Research Center of the Universities Teknologi Malaysia under Grant No R.J130000.7609.4C112the Postdoctoral Grantthe Frontier Materials Research Alliance
文摘Measuring the growth parameters of Ge quantum dots （QDs） embedded in SiO2/Si hetero-structure is pre- requisite for developing the optoelectronic devices such as photovoltaics and sensors. Their optical properties can be tuned by tailoring the growth morphology and structures, where the growth parameters＇ optimizations still need to be explored. We determine the effect of annealing temperature on surface morphology, structures and optical properties of Ge//SiO2//Si hetero-structure. Samples are grown via rf magnetron sputtering and subsequent characterizations are made using imaging and spectroscopic techniques.
基金supported by the National Natural Science Foundation of China (Grant Nos.61170272,61272514,61003287 and 61070163)the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No.20100005120002)+3 种基金the Fok Ying Tong Education Foundation (Grant No.131067)the Shandong Provincial Natural Science Foundation,China (Grant Nos.ZR2011FM023 and ZR2009GM036)the Shandong Province Outstanding Research Award Fund for Young Scientists of China (Grant No.BS2011DX034)the Fundamental Research Funds for the Central Universities (Grant No.BUPT2012RC0221)
文摘In this paper,we first propose a hidden rule among the secure message,the initial tensor product of two Bell states and the final tensor product when respectively applying local unitary transformations to the first particle of the two initial Bell states,and then present a high-efficiency quantum steganography protocol under the control of the hidden rule.In the proposed quantum steganography scheme,a hidden channel is established to transfer a secret message within any quantum secure direct communication(QSDC) scheme that is based on 2-level quantum states and unitary transformations.The secret message hiding/unhiding process is linked with the QSDC process only by unitary transformations.To accurately describe the capacity of a steganography scheme,a quantitative measure,named embedding efficiency,is introduced in this paper.The performance analysis shows that the proposed steganography scheme achieves a high efficiency as well as a good imperceptibility.Moreover,it is shown that this scheme can resist all serious attacks including the intercept-resend attack,measurement-resend attack,auxiliary particle attack and even the Denial of Service attack.To improve the efficiency of the proposed scheme,the hidden rule is extended based on the tensor product of multiple Bell states.
基金National Natural Science Foundation of China(Grant No.U2141230).
文摘For a large-scale array,its realized gain is always smaller than the summation of the element gains in isolation,which is the well-known gain paradox proposed by Hannan.To explain the paradox,embedded element efficiency(EEE)was defined to indicate whether the array elements are being fully utilized,and Hannan’s limit was introduced to provide a fundamental upper bound of the EEE.In this paper,Hannan’s limit is extended to assess the beam-scanning capability of a phased array,which can provide a fundamental upper bound of the EEE corresponding to different scanning angles.In addition,the methods for enhancing the EEE of a large-scale array to approach Hannan’s limit are discussed,including selecting an appropriate power pattern for the array element and efficiently decoupling the array elements.For verification,a planar large-scale wide-angle scanning array utilizing a hybrid decoupling strategy is designed in this paper.The proposed decoupling structure improves the isolation between adjacent array elements in both the E-plane and H-plane by approximately 18.3 dB.The beam-scanning range in the E-plane and H-plane can±65°±60°reach and.During beam scanning,the realized gain of the array can be improved by approximately 0.74 dB.After decoup-×ling,the EEE of the 88 wide-angle scanning array can be improved by approximately 12.64%on average during beam scanning,which is closer to Hannan’s limit.
