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1.
《Information processing & management》2023,60(3):103254
Viewer gifting is an important business mode in live streaming industry, which closely relates to the income of the platforms and streamers. Previous studies on gifting prediction are often limited to cross-section data and consider the problem from the macro perspective of the whole live streaming. However, the multimodal information and the time accumulation effect of live streaming content on viewer gifting behavior are ignored. In this paper, we put forward a multimodal time-series method (MTM) for predicting real-time gifting. The core module of the method is the multimodal time-series analysis (MTA), which targets at effectively fusing multimodal information. Specifically, the proposed orthogonal projection (OP) model can promote cross-modal information interaction without introducing additional parameters. To achieve the interaction of multi-modal information at the same level, we also design a stackable joint representation layer, which makes each target modality's representation (visual, acoustic and textual modality) can benefit from all the other modalities. The residual connections are introduced as well to ensure the integration of low-level and high-level information. On our dataset, our model shows improved performance compared to other advanced models by at least 8% on F1. Meanwhile, the MTA is able to meet the real-time requirements of the live streaming setting, and has demonstrated its robustness and transferability in other tasks. Our research may offer some insights about how to efficiently fuse multimodal information, and contribute to the research on viewer gifting behavior prediction in the live streaming context. 相似文献
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《Information processing & management》2023,60(2):103224
Artificial intelligence (AI) is rapidly becoming the pivotal solution to support critical judgments in many life-changing decisions. In fact, a biased AI tool can be particularly harmful since these systems can contribute to or demote people’s well-being. Consequently, government regulations are introducing specific rules to prohibit the use of sensitive features (e.g., gender, race, religion) in the algorithm’s decision-making process to avoid unfair outcomes. Unfortunately, such restrictions may not be sufficient to protect people from unfair decisions as algorithms can still behave in a discriminatory manner. Indeed, even when sensitive features are omitted (fairness through unawareness), they could be somehow related to other features, named proxy features. This study shows how to unveil whether a black-box model, complying with the regulations, is still biased or not. We propose an end-to-end bias detection approach exploiting a counterfactual reasoning module and an external classifier for sensitive features. In detail, the counterfactual analysis finds the minimum cost variations that grant a positive outcome, while the classifier detects non-linear patterns of non-sensitive features that proxy sensitive characteristics. The experimental evaluation reveals the proposed method’s efficacy in detecting classifiers that learn from proxy features. We also scrutinize the impact of state-of-the-art debiasing algorithms in alleviating the proxy feature problem. 相似文献
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离岸集装箱码头因其岛屿面积限制,难以通过扩建码头内部堆场增加吞吐能力。为解决这个问题,提出一种离岸集装箱码头新装卸工艺模式。新装卸工艺模式是通过在离岸集装箱码头附近的陆域地带建设陆域集疏运堆场,与离岸集装箱码头进行协同装卸作业的模式。陆域集疏运堆场堆存空间分配的目标是满足离岸集装箱码头装卸作业预翻倒要求;单批次输送集装箱的量受到陆岛运输最大通行能力限制。根据上述目标与特点,构建新装卸工艺模式下陆域集疏运堆场堆存空间分配模型,并设计蒙特卡洛树搜索算法进行求解。通过算例分析验证模型的有效性。结果表明该方法能够满足陆域集疏运堆场堆存空间分配需求并提高离岸集装箱码头的吞吐能力。 相似文献
5.
John P. Helveston Yanmin Wang Valerie J. Karplus Erica R.H. Fuchs 《Research Policy》2019,48(1):206-222
A vast literature on technology transitions within industries suggests that early phases of new technologies are marked by periods of intense experimentation, but we know little about the conditions under which these periods emerge. We apply inductive, grounded theory-building techniques to examine what prompts firms to experiment across one emerging technology platform—plug-in electric vehicles (PEVs)—in China. Triangulating annual vehicle make and model sales data from 2003 to 2016 (plus monthly data from 2010 to 2016); 112 English and Mandarin archival documents from industry, academic, and news outlets; and 51 semi-structured interviews with industry, government, and academic stakeholders, we develop four in-depth case studies. We find that in contrast to the innovation trajectories of multinational and Chinese arms of joint venture (JV) firms, independent domestic Chinese firms (those with no history of international JV partnerships) are undertaking significant experimentation across multiple levels—infrastructure, core system, subsystem, and component—of the emerging PEV technology platform. We propose the concept of “institutional complementarities” to describe how interactions among institutions—here the national JV regulation and local market support and subsidies—may have turned regional markets into protected laboratories, extending the incubation periods for independent domestic firm experimentation. While this diverse experimentation may be an important antecedent of technology transition, consolidation induced by national policy standardization or competitive pressure may be required for PEV innovations to scale beyond their early, protected regional markets. 相似文献
6.
Smart cities employ information and communication technologies to improve: the quality of life for its citizens, the local economy, transport, traffic management, environment, and interaction with government. Due to the relevance of smart cities (also referred using other related terms such as Digital City, Information City, Intelligent City, Knowledge-based City, Ubiquitous City, Wired City) to various stakeholders and the benefits and challenges associated with its implementation, the concept of smart cities has attracted significant attention from researchers within multiple fields, including information systems. This study provides a valuable synthesis of the relevant literature by analysing and discussing the key findings from existing research on issues related to smart cities from an Information Systems perspective. The research analysed and discussed in this study focuses on number of aspects of smart cities: smart mobility, smart living, smart environment, smart citizens, smart government, and smart architecture as well as related technologies and concepts. The discussion also focusses on the alignment of smart cities with the UN sustainable development goals. This comprehensive review offers critical insight to the key underlying research themes within smart cities, highlighting the limitations of current developments and potential future directions. 相似文献
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《Information processing & management》2019,56(4):1234-1244
The impact of online reviews on businesses has grown significantly during last years, being crucial to determine business success in a wide array of sectors, ranging from restaurants, hotels to e-commerce. Unfortunately, some users use unethical means to improve their online reputation by writing fake reviews of their businesses or competitors. Previous research has addressed fake review detection in a number of domains, such as product or business reviews in restaurants and hotels. However, in spite of its economical interest, the domain of consumer electronics businesses has not yet been thoroughly studied. This article proposes a feature framework for detecting fake reviews that has been evaluated in the consumer electronics domain. The contributions are fourfold: (i) Construction of a dataset for classifying fake reviews in the consumer electronics domain in four different cities based on scraping techniques; (ii) definition of a feature framework for fake review detection; (iii) development of a fake review classification method based on the proposed framework and (iv) evaluation and analysis of the results for each of the cities under study. We have reached an 82% F-Score on the classification task and the Ada Boost classifier has been proven to be the best one by statistical means according to the Friedman test. 相似文献
8.
Internet of things (IoT) coupled with mobile cloud computing has made a paradigm shift in the service sector. IoT-assisted mobile cloud based e-healthcare services are making giant strides and are likely to change the conventional ways of healthcare service delivery. Though numerous approaches for preventing unauthorized access to information exchanged between a mobile phone and cloud platform do exist, but there is no security mechanism to prevent unauthorized access by the cloud administrators. With an aim to ensure security of client data such as Electronic Patient Records (EPR), we propose a novel high-capacity and reversible data hiding approach for securely embedding EPR within the medical images using Optimal Pixel Repetition (OPR). OPR converts every pixel of the input image to a 2 × 2 block to facilitate reversibility by ensuring all the pixels in a 2 × 2 block to have different values. Since a 2 × 2 block is comprised of 4-pixel elements, which could be arranged in sixteen possible ways; we generate a lookup table corresponding to sixteen possible positions of pixels. EPR hiding in each block is achieved by permuting the pixels of a block according to the four-bit word of secret data, resulting in a histogram invariant stego image. The histogram invariance improves the robustness of the proposed scheme to statistical attacks. A stego image is said to hide embedded data securely, when it provides better imperceptivity for an appreciably high payload. Thus, while using information embedding approach for securing client data on a mobile-cloud platform, high imperceptivity is a desirable feature. Experimental results show that average PSNR obtained is 42 dB for payload 1.25 bpp by our scheme, showing its effectiveness for preventing unauthorized access to client’s sensitive data. 相似文献
9.
《Research Policy》2019,48(9):103789
This paper analyses Amsterdam’s Startup-in-Residence (SiR) programme as new type of policy to engage startups in the development of urban innovation through a challenge-based public procurement of innovation (PPI) process. The programme is being mimicked by other cities and government agencies, but so far there has not been a rigorous, theoretically-informed analysis of the approach. In this paper, we specify and focus on the role of city-based, public-affiliated intermediaries as initiators, moderators and influencers of conversations between startups and the local government. The main contribution of SiR as a PPI intermediation programme has been to launch new types of fruitful conversations on several levels, that lead to institutional innovations rather than direct solutions for urban problems or startup development. In this sense, SiR fulfils a role inquiring and ascribing urban challenges with values and notions of “worth” that preceded and shaped innovation directions. We also suggest that engaging startups is effective for only a limited bandwidth urban challenges; different types of intermediation are required to foster collaborative innovation in more complex settings. 相似文献
10.
《Information processing & management》2019,56(6):102084
We propose a topic-dependent attention model for sentiment classification and topic extraction. Our model assumes that a global topic embedding is shared across documents and employs an attention mechanism to derive local topic embedding for words and sentences. These are subsequently incorporated in a modified Gated Recurrent Unit (GRU) for sentiment classification and extraction of topics bearing different sentiment polarities. Those topics emerge from the words’ local topic embeddings learned by the internal attention of the GRU cells in the context of a multi-task learning framework. In this paper, we present the hierarchical architecture, the new GRU unit and the experiments conducted on users’ reviews which demonstrate classification performance on a par with the state-of-the-art methodologies for sentiment classification and topic coherence outperforming the current approaches for supervised topic extraction. In addition, our model is able to extract coherent aspect-sentiment clusters despite using no aspect-level annotations for training. 相似文献