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  1. null (Ed.)
  2. Cybersecurity competitions are exciting for the game participants; however, the excitement and educational value do not necessarily transfer to audiences because audiences may not be experts in the field. To improve the audiences’ comprehension and engagement levels at these events, we have proposed a virtual commentator architecture for cybersecurity competitions. Based on the architecture, we have developed a virtual animated agent that serves as a commentator in cybersecurity competition. This virtual commentator can interact with audiences with facial expressions and the corresponding hand gestures. The commentator can provide several types of feedback including causal, congratulatory, deleterious, assistive, background, and motivational responses. In addition, when producing speech, the lips, tongue, and jaw provide visual cues that complement auditory cues. The virtual commentator is flexible enough to be employed in the Collegiate Cyber Defense Competitions environment. Our preliminary results demonstrate the architecture can generate phonemes with timestamps and behavioral tags. These timestamps and tags provide solid building blocks for implementing desired responsive behaviors. 
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  3. In this paper, an improved multi-period risk-limiting dispatch (IMRLD) is proposed as an operational method in power systems with high percentage renewables integration. The basic risk-limiting dispatch (BRLD) is chosen as an operational paradigm to address the uncertainty of renewables in this paper due to its three good features. In this paper, the BRLD is extended to the IMRLD so that it satisfies the fundamental operational requirements in the power industry. In order to solve the IMRLD problem, the convexity of the IMRLD is verified. A theorem is stated and proved to transform the IMRLD into a piece-wise linear optimization problem which can be efficiently solved. In addition, the locational marginal price of the IMRLD is derived to analyze the effect of renewables integration on the marginal operational cost. Finally, two numerical tests are conducted to validate the IMRLD. 
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  4. Abstract

    This article presents a 3 × 2 element U‐slot patch antenna array with modified feed for airborne very high frequency applications. The antenna array is designed to upgrade the Multichannel Coherent Radar Depth Sounder/Imager on board the National Aeronautics and Space Administration DC‐8 aircraft. The antenna array is placed in an aerodynamic fairing structure designed for airborne operation. The major objective is to design an antenna array with a wider impedance bandwidth compared to the existing array. Impedance bandwidth improvement is achieved in two steps. First step is by increasing the bandwidth of antenna element itself and the second step is by utilizing the mutual coupling between the elements of the array. To avoid the problem associated with a rigid probe feed, a modified flexible feed is designed, which can withstand the atmospheric and aerodynamic forces at high altitudes. A matching network is used at each antenna element in this array to further improve the impedance matching. The final antenna array with fairing structure achieved a fractional bandwidth of the 62.5% at center frequency of 243.75 MHz.

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  5. Summary

    Two types of tonoplast proton pumps, H+‐pyrophosphatase (V‐PPase) and the H+‐ATPase (V‐ATPase), establish the proton gradient that powers molecular traffic across the tonoplast thereby facilitating turgor regulation and nutrient homeostasis. However, how proton pumps regulate development remains unclear.

    In this study, we investigated the function of two types of proton pumps in Arabidopsis embryo development and pattern formation. While disruption of either V‐PPase or V‐ATPase had no obvious effect on plant embryo development, knocking out both resulted in severe defects in embryo pattern formation from the early stage.

    While the first division in wild‐type zygote was asymmetrical, a nearly symmetrical division occurred in the mutant, followed by abnormal pattern formation at all stages of embryo development. The embryonic defects were accompanied by dramatic differences in vacuole morphology and distribution, as well as disturbed localisation of PIN1. The development of mutant cotyledons and root, and the auxin response of mutant seedlings supported the hypothesis that mutants lacking tonoplast proton pumps were defective in auxin transport and distribution.

    Taking together, we proposed that two tonoplast proton pumps are required for vacuole morphology and PIN1 localisation, thereby controlling vacuole and auxin‐related developmental processes in Arabidopsis embryos and seedlings.

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