Multi-Player War of Attrition with Asymmetric Incomplete Information

This paper models a multi-player war of attrition game with asymmetric incomplete information on the private provision of one public good to investigate the effect of ex-ante asymmetry. In the unique equilibrium, asymmetry leads to a stratified behavior pattern such that one player provides the good instantly with a positive probability, while each of the others has no probability of provision before a certain moment which is idiosyncratic. Comparative statics show that one with less patience, lower cost of provision, and higher reputation in valuation provides uniformly faster. The cost of delay is mainly determined by the strongest type, namely the highest type of the instant-exit player. This paper considers two types of introduction of asymmetry: raising the strongest type tends to improve efficiency, whereas controlling the strongest type aligns the effect of asymmetry with the sign of an intuitive measure of the cost of symmetry

Energy efficient cutting parameter optimization

Mechanical manufacturing industry consumes substantial energy with low energy efficiency. Increasing pressures from energy price and environmental directive force mechanical manufacturing industries to implement energy efficient technologies for reducing energy consumption and improving energy efficiency of their machining processes. In a practical machining process, cutting parameters are vital variables set by manufacturers in accordance with machining requirements of workpiece and machining condition. Proper selection of cutting parameters with energy consideration can effectively reduce energy consumption and improve energy efficiency of the machining process. Over the past 10 years, many researchers have been engaged in energy efficient cutting parameter optimization, and a large amount of literature have been published. This paper conducts a comprehensive literature review of current studies on energy efficient cutting parameter optimization to fully understand the recent advances in this research area. The energy consumption characteristics of machining process are analyzed by decomposing total energy consumption into electrical energy consumption of machine tool and embodied energy of cutting tool and cutting fluid. Current studies on energy efficient cutting parameter optimization by using experimental design method and energy models are reviewed in a comprehensive manner. Combined with the current status, future research directions of energy efficient cutting parameter optimization are presented

An Examination of the Causal Relationship Between Tourism and Economic Growth in Ghana from 1987 to 2018

The growth of every nation is its ability to improve every sector of the economy that provides better outcomes through revenue mobilization and investment. With the Ghana’s attention shifted to tourism, it is imperative to identify how tourism could trigger growth in the country. Thus, the study sought to examine the causal relationship between tourism and economic growth of Ghana and its related challenges. The study adopted a mixed method approach in the collection and analysis of data. Both secondary and primary data were used in the analysis of the study. In analyzing the quantitative study, data on tourism and GDP from 1987 to 2018 were used. The study adopted the Johansen Cointegration test and the instrumental variable estimation to identify the causal relationship among the variables. The outcome of the study from the Johansen and Co-integration test instrumental variable showed that there is a unidirectional causal relationship between tourism receipt and GDP growth both in the short run and the long run and a positive significant effect of tourism on economic growth of Ghana. The result showed that government has been the major contributor to the sector. Also, the most challenging issue curtailing the sector was found to be the issue of the COVID 19 pandemic. As such, the study recommended that ensuring public-private partnership could improve the sector to ensure growth in the economy. Further extensive research is required to understand the effects of tourism on host communities. Keywords: Tourism, Gross Domestic Product (GDP), Economic Growth, Ghana, Tourism industry, Climate Change. DOI: 10.7176/JESD/11-20-04 Publication date:October 31st 202

Organic Sulphur Transfers in Coke Oven Gas via Noncatalytic Partial Oxidation

The organic sulfur transformation was studied during coke oven gas to produce syngas via noncatalytic partial oxidation. The concentration of CS2 and thiophene was examined in syngas by sulfide detector. For comparison, the sulfur transfer was also studied in coke oven gas under dry and hydrous conditions. When the ratio of O2 / Gas was 0.32, complete thiophene and about 83% of CS2 in feed gas could be transformed via noncatalytic partial oxidation in the dry condition. It was mainly because of burner nozzle unique structure forming local hyperthemia, which benefited OH, O free radical and active atoms. During steam transforming to produce syngas, the ratio of water to carbon was less than 3, a higher ratio of O2/Gas favored sulfur transformation. However, compared to dry feed, transforming rate of CS2 and thiophene was decreased. This indicates that the steam added was disadvantageous to the transformation of organic sulphur during the production of syngas by noncatalytic partial oxidation, steam and mass H2S in feed gas, resulting in the decrease of local hyperthermia temperature and the formation of organic sulfu

Quasiphoton at the Subcycle Level in Strong-Field Ionization

Photon is an energy quanta of light that does not exist at the sub-optical-cycle level. Exploiting the dynamical rotational symmetry of circularly or elliptically polarized light pulses, however, we demonstrate the existence of quasiphotons down to the subcycle level. We illustrate the concept of quasiphotons in strong-field ionization through the correlated spectrum of angular momentum and energy (SAME) of photoelectrons, both at the tunnel exit and in the asymptotic region. Moreover, we propose a protocol based on electron vortices to directly visualize the existence of quasiphotons. Our work paves the pathway towards a deeper understanding of fundamental light-matter interactions with photonic characteristics on the subcycle scale.Comment: 6 pages, 4 figure

M2C: Towards Automatic Multimodal Manga Complement

Multimodal manga analysis focuses on enhancing manga understanding with visual and textual features, which has attracted considerable attention from both natural language processing and computer vision communities. Currently, most comics are hand-drawn and prone to problems such as missing pages, text contamination, and aging, resulting in missing comic text content and seriously hindering human comprehension. In other words, the Multimodal Manga Complement (M2C) task has not been investigated, which aims to handle the aforementioned issues by providing a shared semantic space for vision and language understanding. To this end, we first propose the Multimodal Manga Complement task by establishing a new M2C benchmark dataset covering two languages. First, we design a manga argumentation method called MCoT to mine event knowledge in comics with large language models. Then, an effective baseline FVP-M$^{2}$ using fine-grained visual prompts is proposed to support manga complement. Extensive experimental results show the effectiveness of FVP-M$^{2}$ method for Multimodal Mange Complement.Comment: EMNLP2023. arXiv admin note: text overlap with arXiv:2210.1546

MSG-BART: Multi-granularity Scene Graph-Enhanced Encoder-Decoder Language Model for Video-grounded Dialogue Generation

Generating dialogue grounded in videos requires a high level of understanding and reasoning about the visual scenes in the videos. However, existing large visual-language models are not effective due to their latent features and decoder-only structure, especially with respect to spatio-temporal relationship reasoning. In this paper, we propose a novel approach named MSG-BART, which enhances the integration of video information by incorporating a multi-granularity spatio-temporal scene graph into an encoder-decoder pre-trained language model. Specifically, we integrate the global and local scene graph into the encoder and decoder, respectively, to improve both overall perception and target reasoning capability. To further improve the information selection capability, we propose a multi-pointer network to facilitate selection between text and video. Extensive experiments are conducted on three video-grounded dialogue benchmarks, which show the significant superiority of the proposed MSG-BART compared to a range of state-of-the-art approaches.Comment: 5 pages,3 figure

Uneven-Layered Coding Metamaterial Tile for Ultrawideband RCS Reduction and Diffuse Scattering

In this paper, a novel uneven-layered coding metamaterial tile is proposed for ultra-wideband radar cross section (RCS) reduction and diffuse scattering. The metamaterial tile is composed of two kinds of square ring unit cells with different layer thickness. The reflection phase difference of 180° (±37°) between two unit cells covers an ultra-wide frequency range. Due to the phase cancellation between two unit cells, the metamaterial tile has the scattering pattern of four strong lobes deviating from normal direction. The metamaterial tile and its 90-degree rotation can be encoded as the ‘0’ and ‘1’ elements to cover an object, and diffuse scattering pattern can be realized by optimizing phase distribution, leading to reductions of the monostatic and bi-static RCSs simultaneously. The metamaterial tile can achieve −10 dB RCS reduction from 6.2 GHz to 25.7 GHz with the ratio bandwidth of 4.15:1 at normal incidence. The measured and simulated results are in good agreement and validate the proposed uneven-layered coding metamaterial tile can greatly expanding the bandwidth for RCS reduction and diffuse scattering