442 research outputs found
Being recognized in an algorithmic system: Cruel optimism in gay visibility on Douyin and Zhihu
© The Author(s) 2022. This article is distributed under the terms of the Creative Commons Attribution-Non Commercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/)Drawing upon “algorithmic ethnography” (Christin, 2020), this article enrolls algorithms to gather qualitative data to examine how Chinese social media platforms and their algorithms intersect with gay visibility. By looking critically into the ways that gay romance and HIV-related content are generated on Douyin and Zhihu, respectively, we argue that algorithmic gay visibility serves as a form of cruel optimism, which becomes a profitable convenience for corporate social media platforms and operates in an exclusionary matrix. The content that ordinary Chinese gay men are presented with (for example, the able-bodied, romanticized normative gay relationship and overly optimistic self-help advice for gay men living with HIV) is economically viable, which produces trending and monetizable items, including music tracks, viral dance routines and challenges, personas, medicine promotions, as well as commercial healthcare training and marketing. In contrast, non-conforming bodies, non-monogamous and queer relationships, as well as the depression, stigma and discrimination experienced by gay men living with HIV are algorithmically invisible.Peer reviewe
Dynamic Evolutionary Game Analysis of Symbiosis System in E-commerce Industrial Park
Based on the evolutionary game theory and the bounded rational and asymmetric information assumptions, we construct the dynamic evolutionary game model between the three game players and analyze the replication dynamic equations. Furthermore, we analyze the strategy of three symbiosis units and the evolution mechanism of E-commerce industrial park symbiosis system. Finally, two conclusions are drawn: Conclusion 1, the probability that three symbiosis units of E-commerce Industrial Park choosing the symbiosis strategy increases with increase of the probability that the other two symbiosis units selecting the symbiosis strategy. Conclusion 2, the probability of the symbiosis unit to choose the symbiosis strategy increase with the increase of the benefit and decrease with the increase of the cost, risk and loss
Influence of variability and uncertainty of wind and waves on fatigue damage of a floating wind turbine drivetrain
publishedVersio
Technical and Economic Feasibility Analysis of a Conceptual Subsea Freight Glider for CO2 Transportation
This study analyses the technical and economic aspects of a novel subsea freight glider (SFG). The SFG is an excellent replacement for tanker ships and submarine pipelines transporting liquefied CO2. The main aim of the SFG is to ship CO2 from an offshore facility to an underwater well where the gas can be injected; as an advantage, the SFG vehicle may be used to transport all kinds of cargo. The SFG travels below the sea surface, making the vessel weather-independent. The research is divided into two steps. Firstly, the technical feasibility analysis is performed by designing a baseline design with a length of 56.5 m, a beam of 5.5 m, and a cargo volume of 1194 m3. The SFG is developed using DNVGL-RU-NAVAL-Pt4Ch1, which was initially created for military submarine designs. Two additional half-scaled 469 m3 and double-scaled 2430 m3 models are created when the baseline design fulfils the technical requirements. Secondly, the economic analysis is carried out using the freely accessible MUNIN D9.3 and ZEP reports. The economic feasibility analysis is illustrated through a case study with a CO2 transport capacity range of 0.5 to 2.5 mtpa (million tons per annum) and a transport length range of 180 km to 1500 km. The prices of CO2 per ton for the SFG, crew and autonomous tankers, and offshore pipelines are comprehensively compared. According to the results, SFGs with capacities of 469 m3, 1194 m3, and 2430 m3 are technically possible to manufacture. Moreover, the SFGs are competitive with a smaller CO2 capacity of 0.5 mtpa at distances of 180 and 500 km and a capacity of 1 mtpa at a distance of 180 km.publishedVersio
Determination of extreme responses of USFG’s equilibrium glide path hovering in ocean current
The UiS subsea-freight glider (USFG) is a state-of-the-art autonomous vessel designed to be an alternative to existing transportation technologies and serve the demands of small-scale fields for CO2 transportation. Generally, these smaller fields cannot economically justify the costs of large tankers, cargo ships, or underwater pipelines on the seabed, as the transport volume is nominal compared to larger fields. The USFG can travel underwater at an operational depth of 200 m, allowing the glider to carry freight operations without considering ideal weather windows. It can manoeuvre itself underwater by monitoring the flow between the ballast tanks aboard. During the entire mission of the USFG, from capturing to injection locations, it follows a pre-laid saw-tooth path while experiencing transient loads from the ocean current. The extreme surge and heave responses of the USFG are vital for its design. Extreme motion along the surge direction affects the range of the glider (vital for battery design) and the dynamic controller parameters concerning manoeuvrability. For this paper, the averaged conditional exceedance rate (ACER) is employed to scrutinize the extreme motion (surge direction) of the USFG while gliding to a defined depth. This is done when the glider is exposed to an average current velocity of 0.5 m/s and 1.0 m/s. The data used for analysis in this study is obtained from the time-domain simulations carried out on a two-dimensional mathematical model developed in Simulink. The presented ACER method efficiently uses the available data points and accurately predicts the extreme surge responses precisely and accurately. This study can effectively promote the design improvement of the USFG; thus, the safety and economic benefits can be essentially enhanced.publishedVersio
A comparison study of power performance and extreme load effects of large 10-MW offshore wind turbines
The utilisation of offshore wind turbines has rapidly increased in the last decade, which has resulted in a steady increase in wind turbine sizes. The global average offshore wind turbine size has increased from 1.5 MW to 6 MW in the last two decades. The research community has started to investigate huge 10 to 15 MW offshore wind turbines in recent years, resulting in the study of very innovative floating wind turbines using various substructure technologies. With this backdrop, this paper will investigate and thoroughly compare the power performance of extreme load effects of a large offshore 10 MW turbine installed on the monopile, spar, and semisubmersible substructures. This is performed by using the average conditional exceedance rate (ACER) and Gumbel methods to predict the extreme responses under the operating conditions of 8, 12, and 16 m/s mean wind speed, representing the below-rated, rated, and above-rated regions, respectively. The results show that the power performance and extreme loads experienced depends significantly on the operating regions. The mean power generation between the three different types of offshore wind turbines (OWTs) are closely in the whole operating range, which standard deviations differ significantly. Large standard deviations of power generation appear in the spar turbine under the below-rated condition. Further, it was observed that the spar wind turbine generally experiences larger extreme loads due to larger platform pitch motion. In addition, the ACER method shows a better prediction for the 1, 2 and 5-year extreme responses than the Gumbel method, which is due to the relatively poor data fitting of the Gumbel method at the upper tail. The study is believed to consolidate and close the knowledge gap in understanding wind turbine responses across the most common offshore substructure technologies and provide a basis for design and deployment of OWTs.publishedVersio
Semantic Communications with Ordered Importance using ChatGPT
This letter proposes a novel semantic communication scheme with ordered
importance (SCOI) using the chat generative pre-trained transformer (ChatGPT).
In the proposed SCOI scheme, ChatGPT plays the role of a consulting assistant.
Given a message to be transmitted, the transmitter first queries ChatGPT to
output the importance order of each word. According to the importance order,
the transmitter then performs an unequal error protection transmission strategy
to make the transmission of essential words more reliable. Unlike the existing
semantic communication schemes, SCOI is compatible with existing source-channel
separation designs and can be directly embedded into current communication
systems. Our experimental results show that both the transmission bit error
rate (BER) of important words and the semantic loss measured by ChatGPT are
much lower than the existing communication schemes
‘Sissy capital’ and the governance of non-normative genders in China’s platform economy
This article examines Chinese government censorship in the intersection between queer and fan cultures and its regulation of big tech companies and platform economies in the 2020s conjuncture. In the context of booming platform industries and proliferating queer representations, the government issued explicit directives to censor the representation of 'sissy men', or androgynous and effeminate male celebrities, on video-streaming platforms in 2021. Accused of encouraging 'sissy capital', the digital platforms that produce or host these videos have also been closely scrutinized. Focusing on the discourse of sissy capital, this article traces how the term has been used in state policies and mainstream media to discern the power relations that produce such a discourse. It argues that in the context of China's fast-developing digital platform economy in which the pink economy plays a part, the governance of non-normative sexualities and platform industries has converged in the government's efforts to define and regulate culture in an era of digital capitalism. The term sissy capital points to the gendered dimension of capita
Improving extreme anchor tension prediction of a 10-MW floating semi-submersible type wind turbine, using highly correlated surge motion record
Extreme value prediction of the load-effect responses of complex offshore structures such as the floating wind turbine (FWT) is crucial in ultimate limit state (ULS) design. This paper considers two cases to understand the feasibility of the bivariate correction on the extreme load and motion responses of a 10-MW semi-submersible type FWT. The empirical anchor tension force and surge motion used in this study are obtained from the FAST simulation tool (developed by the National Renewable Energy Laboratory) with the load cases stimulated at under-rated, rated and above rated speeds. Then, the bivariate correction method is applied to model FWT extreme response for a 5-years return period prediction with a 95% confidence interval (CI), based on just 2 min short response record. The proposed methodology permits accurate correction of the bivariate extreme value in case of, for example, corrupted measurement sensor data. Based on the proposed novel method’s performance, it is concluded that the bivariate correction method can offer better robust and precise bivariate predictions of coupled surge motion and anchor tension of the FWT.publishedVersio
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