Ordering-sensitive and Semantic-aware Topic Modeling

Topic modeling of textual corpora is an important and challenging problem. In most previous work, the "bag-of-words" assumption is usually made which ignores the ordering of words. This assumption simplifies the computation, but it unrealistically loses the ordering information and the semantic of words in the context. In this paper, we present a Gaussian Mixture Neural Topic Model (GMNTM) which incorporates both the ordering of words and the semantic meaning of sentences into topic modeling. Specifically, we represent each topic as a cluster of multi-dimensional vectors and embed the corpus into a collection of vectors generated by the Gaussian mixture model. Each word is affected not only by its topic, but also by the embedding vector of its surrounding words and the context. The Gaussian mixture components and the topic of documents, sentences and words can be learnt jointly. Extensive experiments show that our model can learn better topics and more accurate word distributions for each topic. Quantitatively, comparing to state-of-the-art topic modeling approaches, GMNTM obtains significantly better performance in terms of perplexity, retrieval accuracy and classification accuracy.Comment: To appear in proceedings of AAAI 201

Translating Phrases in Neural Machine Translation

Phrases play an important role in natural language understanding and machine translation (Sag et al., 2002; Villavicencio et al., 2005). However, it is difficult to integrate them into current neural machine translation (NMT) which reads and generates sentences word by word. In this work, we propose a method to translate phrases in NMT by integrating a phrase memory storing target phrases from a phrase-based statistical machine translation (SMT) system into the encoder-decoder architecture of NMT. At each decoding step, the phrase memory is first re-written by the SMT model, which dynamically generates relevant target phrases with contextual information provided by the NMT model. Then the proposed model reads the phrase memory to make probability estimations for all phrases in the phrase memory. If phrase generation is carried on, the NMT decoder selects an appropriate phrase from the memory to perform phrase translation and updates its decoding state by consuming the words in the selected phrase. Otherwise, the NMT decoder generates a word from the vocabulary as the general NMT decoder does. Experiment results on the Chinese to English translation show that the proposed model achieves significant improvements over the baseline on various test sets.Comment: Accepted by EMNLP 201

He who helps others becomes helpless : the paradox between organisational values and workforce sustainability in the UK third sector

This research aims to question and uncover the social sustainability paradox arising from the inconsistent practice of third sector organisations’ values, for both their external stakeholders and internal workforce. To achieve so, this thesis discusses how the values are created, delivered and affected through the topology of the third sector, the organisational theories, sustainability theory and game theory. It is identified that altruism is a common trait for the workforce, which works to serve the public benefits. However, the workforce can be impacted through the donor control under the professionalism influences. Hence, there appeared tensions between the third sector organisations and their workforce. Such tensions are associated concerns of social sustainability. In the efforts to unravel the themes behind the tensions, various sets of theories are reviewed and compared. Through the theoretical emergence and evidence of employment hardship, the social sustainability theory is used to examine the tensions between internal value realisation and external value delivery. The lenses of stewardship/democracy governance theories and managerial leadership are applied to develop subset models of sustainability as the hypotheses to reach value consistency. Lastly, the examinations are placed under the prisoner’s dilemma theory to echo the importance of consistency of third sector’s intrinsic and extrinsic values. In turn, the cooperation links for governance theories and managerial leadership through horizontal communications and power relations are verified for the strategic importance to achieve social sustainability for the third sector workforce. The limitations of this research can be attributable to the simplification and generalisation processes of the theory applications and the definition of the third sector. In addition, the possibility of undiscovered theories and practices, adding to the test of research, can entail the likelihood of different findings or prove otherwise the findings of emergent theories as discovered hereunder

Quantum coherence of the molecular states and their corresponding currents in nanoscale Aharonov-Bohm interferometers

By considering a nanoscale Aharonov-Bohm (AB) interferometer containing a parrallel-coupled double dot coupled to the source and drain electrodes, we investigate the AB phase oscillations of transport current via the bonding and antibonding state channels. The results we obtained justify the experimental analysis given in [Phys. Rev. Lett. \textbf{106}, 076801 (2011)] that bonding state currents in different energy configurations are almost the same. On the other hand, we extend the analysis to the transient transport current components flowing through different channels, to explore the effect of the parity of bonding and antibonding states on the AB phase dependence of the corresponding current components in the transient regime. The relations of the AB phase dependence between the quantum states and the associated current components are analyzed in details, which provides useful information for the reconstruction of quantum states through the measurement of the transport current in such systems. With the coherent properties in the quantum dot states as well as in the transport currents, we also provide a way to manipulate the bonding and antibonding states by the AB magnetic flux.Comment: 10 pages, 7 figure

Building Web Based Collaboration Systems in Supply Chain Management: A Conceptual Framework

Good collaboration plays an important role in effective supply chain management. The main obstacle to collaboration within a supply chain is a conflict between each enterprise’s local optimization and the chain’s global optimization. We show that in addition to relationships, trust, contract and other social factors, sharing and reallocation of payoff are critical to align the objective of each member enterprise from local optimization to global optimization. We propose collaboration systems, which take advantage of information technology in the digital economy, to set up payoff reallocation and information sharing mechanism. These systems can be used to foster solid collaboration relationships within one supply chain. We identify the system requirements and outline the Web-based systems schema. The collaboration systems have four indivisible components: measuring performance; monitoring performance and payoff re-allocation; global optimization algorithm, and reconfiguration: planning, forecasting and recommendation. The challenges, impediments and enablers to implement the proposed collaboration systems are also discussed in the paper

Virus Attack Uncertainty, Moral Hazard and Proposed Solution in Antivirus Software Market

This paper investigates the antivirus market from the perspective of social welfare and market efficiency. It analyzes the uncertainty characteristic of virus attacks and the moral hazard problem from the antivirus software vendor. It also proposes one potential solution, that is, antivirus contracting between IT users and the antivirus software vendor, to reduces the transaction cost and alleviate the moral hazard problem in the antivirus market

Peer-and-Self Assessment to Reveal the Ranking of Each Individual\u27s Contribution to a Group Project

Teamwork and virtual teamwork are becoming more and more important in IS professions. Group project assignments play an important role to train students\u27 skills in teamwork in IS education. To reduce the free-rider problem and treat each group member fairly, the instructor needs to distinguish each individual\u27s contribution to a group project. In this paper, we analyze one commonly used peer-and-self assessment application and point out its critical drawback: the deduced ranking might be wrong as some members do not tell the truth. Alternatively, we propose an effective mechanism to modify the peer-and-self assessment. Under the revised peer-and-self assessment, truth-telling is each individual\u27s dominant strategy and the instructor can effectively distinguish each member\u27s contribution to a group project. A field experiment and the associated survey are used to validate the revised self-and-peer assessment approach. Generally, the revised peer-and-self assessment is acceptable to students and it is a valid, effective, and useful tool to the instructor