36 research outputs found
Relay Assisted Cooperative OSTBC Communication with SNR Imbalance and Channel Estimation Errors
In this paper, a two-hop relay assisted cooperative Orthogonal Space-Time
Block Codes (OSTBC) transmission scheme is considered for the downlink
communication of a cellular system, where the base station (BS) and the relay
station (RS) cooperate and transmit data to the user equipment (UE) in a
distributed fashion. We analyze the impact of the SNR imbalance between the
BS-UE and RS-UE links, as well as the imperfect channel estimation at the UE
receiver. The performance is analyzed in the presence of Rayleigh flat fading
and our results show that the SNR imbalance does not impact the spatial
diversity order. On the other hand, channel estimation errors have a larger
impact on the system performance. Simulation results are then provided to
confirm the analysis.Comment: 5 pages, 3 figures, IEEE 69th Vehicular Technology Conferenc
Summary Statistic Privacy in Data Sharing
We study a setting where a data holder wishes to share data with a receiver,
without revealing certain summary statistics of the data distribution (e.g.,
mean, standard deviation). It achieves this by passing the data through a
randomization mechanism. We propose summary statistic privacy, a metric for
quantifying the privacy risk of such a mechanism based on the worst-case
probability of an adversary guessing the distributional secret within some
threshold. Defining distortion as a worst-case Wasserstein-1 distance between
the real and released data, we prove lower bounds on the tradeoff between
privacy and distortion. We then propose a class of quantization mechanisms that
can be adapted to different data distributions. We show that the quantization
mechanism's privacy-distortion tradeoff matches our lower bounds under certain
regimes, up to small constant factors. Finally, we demonstrate on real-world
datasets that the proposed quantization mechanisms achieve better
privacy-distortion tradeoffs than alternative privacy mechanisms
Skeleton-of-Thought: Large Language Models Can Do Parallel Decoding
This work aims at decreasing the end-to-end generation latency of large
language models (LLMs). One of the major causes of the high generation latency
is the sequential decoding approach adopted by almost all state-of-the-art
LLMs. In this work, motivated by the thinking and writing process of humans, we
propose "Skeleton-of-Thought" (SoT), which guides LLMs to first generate the
skeleton of the answer, and then conducts parallel API calls or batched
decoding to complete the contents of each skeleton point in parallel. Not only
does SoT provide considerable speed-up (up to 2.39x across 11 different LLMs),
but it can also potentially improve the answer quality on several question
categories in terms of diversity and relevance. SoT is an initial attempt at
data-centric optimization for efficiency, and reveal the potential of pushing
LLMs to think more like a human for answer quality.Comment: Technical report, work in progres
The physio-biochemical characterization reflected different calcium utilization efficiency between the sensitive and tolerant peanut accessions under calcium deficiency
Peanut yield in southern China is usually limited by calcium deficiency in soil. Most previous studies have found that small-seed varieties showed higher tolerance than large-seed varieties (e.g. Virginia type) under calcium deficiency, however, our preliminary research found that sensitive varieties also existed in small-seed counterparts. Few studies have been conducted to characterize low-calcium tolerance among small-seed germplasms with genetic diversity, and the differences in physiological characteristics between sensitive and tolerant varieties has not been reported yet. Thus, in order to better understand such differences, the current study firstly collected and characterized a diversity germplasm panel consisting of 50 small-seed peanut genotypes via a 2-year field trial, followed by the physiological characterization in sensitive (HN032) and tolerant (HN035) peanut genotypes under calcium deficiency. As a result, the adverse effects brought by calcium deficiency on calcium uptake and distribution in HN032 was much larger than HN035. In details, calcium uptake in the aboveground part (leaves and stems) was reduced by 16.17% and 33.66%, while in the underground part (roots and pods), it was reduced by 13.69% and 68.09% under calcium deficiency for HN035 and HN032, respectively; The calcium distribution rate in the pods of HN035 was 2.74 times higher than HN032. The utilization efficiency of calcium in the pods of HN035 was 1.68 and 1.37 times than that of HN032 under calcium deficiency and sufficiency, respectively. In addition, under calcium deficiency conditions, the activities of antioxidant enzymes SOD, POD, and CAT, as well as the MDA content, were significantly increased in the leaves of HN032, peanut yield was significantly reduced by 22.75%. However, there were no significant changes in the activities of antioxidant enzymes, MDA content, and peanut yield in HN035. Therefore, higher calcium absorption and utilization efficiency may be the key factors maintaining peanut yield in calcium-deficient conditions for tolerant genotypes. This study lays a solid foundation for selecting low-calcium tolerant varieties in future peanut breeding
Selective Pre-training for Private Fine-tuning
Suppose we want to train text prediction models in email clients or word
processors. The models must preserve the privacy of user data and adhere to a
specific fixed size to meet memory and inference time requirements. We
introduce a generic framework to solve this problem. Specifically, we are given
a public dataset and a private dataset
corresponding to a downstream task . How should we pre-train a fixed-size
model on and fine-tune it on such that
performance of with respect to is maximized and satisfies
differential privacy with respect to ? We show that pre-training
on a {\em subset} of dataset that brings the public distribution
closer to the private distribution is a crucial ingredient to maximize the
transfer learning abilities of after pre-training, especially in the
regimes where model sizes are relatively small. Besides performance
improvements, our framework also shows that with careful pre-training and
private fine-tuning, {\em smaller models} can match the performance of much
larger models, highlighting the promise of differentially private training as a
tool for model compression and efficiency