Duistermaat-Heckman measure and the mixture of quantum states

In this paper, we present a general framework to solve a fundamental problem in Random Matrix Theory (RMT), i.e., the problem of describing the joint distribution of eigenvalues of the sum \bsA+\bsB of two independent random Hermitian matrices \bsA and \bsB. Some considerations about the mixture of quantum states are basically subsumed into the above mathematical problem. Instead, we focus on deriving the spectral density of the mixture of adjoint orbits of quantum states in terms of Duistermaat-Heckman measure, originated from the theory of symplectic geometry. Based on this method, we can obtain the spectral density of the mixture of independent random states. In particular, we obtain explicit formulas for the mixture of random qubits. We also find that, in the two-level quantum system, the average entropy of the equiprobable mixture of $n$ random density matrices chosen from a random state ensemble (specified in the text) increases with the number $n$. Hence, as a physical application, our results quantitatively explain that the quantum coherence of the mixture monotonously decreases statistically as the number of components $n$ in the mixture. Besides, our method may be used to investigate some statistical properties of a special subclass of unital qubit channels.Comment: 40 pages, 10 figures, LaTeX, the final version accepted for publication in J. Phys.

Neutral Tone in Mandarin: Representation and Interaction with Utterance-level Prosody

In Standard Mandarin, there are syllables that do not carry any of the four citation tones (T1: High-level tone, T2: Mid-rising tone, T3: Low-convex tone and T4: High-falling tone), and they are said to have a neutral tone (NT). These syllables are usually shorter, lighter, prosodically grouped with the preceding CT-bearing syllables. These characteristics of NT have led to a prevailing view that it has no underlying phonological specification. However, research has focused more on how the surface pitch variations of NT are realized rather than the underlying representation of NT. In contrast, morphological, sociolinguistic and diachronic work on NT has suggested that NT may not be a homogeneous entity. In this thesis, I provide acoustic and psycholinguistic evidence that there are two types of NT, Intrinsic NT and Derived NT. Intrinsic NT refers to morphemes that were lexicalized as tone-deleted, unstressed syllables even before the formation of the four CTs of modern Mandarin. Derived NT refers to morphemes derived from the CTs via stress-related tone-deletion. In Part A, the phonological representation of Intrinsic and Derived NT is explored through two production and two processing experiments. The results show that Intrinsic NT is likely to have an underspecified tonal target while Derived NTs are underlyingly CTs. In addition, both subtypes of NT are metrically light, unlike heavy CTs. Part B explores the interaction between NTs and utterance-level prosody in production and perception experiments. NT-bearing syllables have lengthening patterns under focus similar to CT-bearing syllables, in contrast to the realization of unstressed syllables in English. In perception, the identification of intonation (Statement vs. Question) on Intrinsic NT was similar to Derived NT. When compared to CTs, the NTs elicit less bias towards question than T4, and higher accuracy than T2, which may result from their simpler surface representations.CHINA Scholarship COUNCIL (CSC) and Cambridge Trus

Review and Analysis of Electronic Data Forensics Rules in Network Remote Survey

With the rapid development of open network environment in China, its influence is more and more far-reaching. When it comes to the forensics in the field of investigation measures, it is mainly embodied in electronic data and its network extraction. Network extraction includes network remote inspection of evidence collection mode, from the traditional hands-on, contact type gradually to remote, non-contact type. However, in China's current judicial theory, the legal nature and definition of network remote inspection are not clear, and even the rules themselves are unreasonable or contradictory. In practice, it is mainly reflected in a series of difficult situations in application, such as improper use due to unclear concept and nature, or mixed use with other investigation measures. These will eventually lead to the non-standard and illegal electronic forensics, the loss of protection of citizens' privacy rights, and the failure of the system of investigation links. To better implement fixed and extraction of link to the network evidence investigation and necessary based on the existing system for the existing rules are more comprehensive and systematic carding and analysis, clarify the legal nature of network remote inquest and legal position of, in order to improve the network remote electronic data evidence rules in the system of inspection

Heart Rate Variability as a Biomarker for Working Memory Performance and Fatigue Perception

Fatigue is a debilitating condition especially in the emergency response (ER) domain where long work hours and sustained cognitive demands impede job performance. Typical solutions such as pharmacological aids (e.g., caffeine or other stimulants), or user-interface alterations (e.g., multimodal feedback) do not address the root of the problem. This is partly because fatigue is a complex, non-linear phenomenon influenced by lifelong subjective experiences and neurophysiological responses. Personalized and task-specific modes of intervention, beyond pharmacological aids, could improve work conditions and the outcome for all stakeholders. Heart rate variability (HRV) is a commonly used non-invasive diagnostic index of cardiac autonomous regulation. Previous studies have discovered strong links between cardiac processes and a variety of prefrontal neural responses, as well as pointing to HRV as an indicator of cognitive performance level and working memory (WM). The electrocardiogram (ECG) is a commonly used non-invasive diagnostic tool; and ECG data have been used in a variety of medical research, such as biometric human identification and sleep staging. We take data from a fatigue experiment done by our group that investigated the use of transcranial direct current stimulation (tDCS) – a non-invasive brain stimulation technique on mitigating fatigue and improving individual working memory (WM) performance. The study used a repeated measure, counterbalanced Latin square design where participants were randomly grouped under control, sham or anodal conditions. Subjective responses, WM performance, and HRV data were recorded. We hypothesize that: (1) individuals with higher resting-state HRV will exhibit better performance and report lower levels of perceived fatigue; and (2) changes in HRV during tasks will be associated with concurrent, positively related changes in performance and (or) negatively related changes in fatigue perception. This study intends to unveil the relationship between HRV, WM performance, and fatigue perceptions. We will investigate the relevance of resting-state and time-on-task changes in HRV on reflecting fatigue perceptions and task performance during the WM exercise. Ultimately, we aim to provide a fieldable and unobtrusive measurement of fatigue for emergency responders using HRV that will contribute to personalized fatigue countermeasures

A Workshop of Gamifying the Writing Consultant Education

The purpose of this workshop is to introduce gamification for writing consultant education and to walk attendees through a hands-on experience of gamifying. Attendees will participate in a five-step design process: setting goals, analyzing learners and contents, assigning experience points and levels, selecting appropriate achievement for badges, and creating an evaluation plan. The learning outcomes are expected to be theoretical foundations about gamification, design-based thinking, creative and critical thinking, and applicable gamification cases

IT ENABLED ENVIRONMENTALLY FRIENDLY CONSUMPTION: IT FEATURES ADDRESSING CHALLENGES IN CONSUMER DECISION MAKING

The objective of this study is to investigate how IT may facilitate green consumption. Leveraging the Theory of Planned Behavior (TPB), the study proposes a framework to analyze the challenges consumers face in green consumption decisions. Challenges are identified in three dimensions: attitude formation, subjective norm, and perceived behavioral control. This framework can be generalized to various consumption scenarios, and help researchers as well as application designers identify context specific challenges. The study then explains how IT applications/features may address the challenges. Social networking features enable individuals to go beyond their real world networks and connect with online friends who share the environmental concerns. Accordingly, the pool of relevant others changes, and individuals are more likely to be encouraged to consume environmentally friendly. Platforms of user generated contexts enable individuals to share their experiences and exert influence on others, and thus enhance individual?s motivation for green consumption. The conceptual arguments are illustrated with a case study on Seafood Watch, which demonstrates how IT helps with ocean friendly fish consumption