Management of spatial data for visualization on mobile devices

Vector-based mapping is emerging as a preferred format in Location-based Services(LBS), because it can deliver an up-to-date and interactive map visualization. The Progressive Transmission(PT) technique has been developed to enable the ecient transmission of vector data over the internet by delivering various incremental levels of detail(LoD). However, it is still challenging to apply this technique in a mobile context due to many inherent limitations of mobile devices, such as small screen size, slow processors and limited memory. Taking account of these limitations, PT has been extended by developing a framework of ecient data management for the visualization of spatial data on mobile devices. A data generalization framework is proposed and implemented in a software application. This application can signicantly reduce the volume of data for transmission and enable quick access to a simplied version of data while preserving appropriate visualization quality. Using volunteered geographic information as a case-study, the framework shows exibility in delivering up-to-date spatial information from dynamic data sources. Three models of PT are designed and implemented to transmit the additional LoD renements: a full scale PT as an inverse of generalisation, a viewdependent PT, and a heuristic optimised view-dependent PT. These models are evaluated with user trials and application examples. The heuristic optimised view-dependent PT has shown a signicant enhancement over the traditional PT in terms of bandwidth-saving and smoothness of transitions. A parallel data management strategy associated with three corresponding algorithms has been developed to handle LoD spatial data on mobile clients. This strategy enables the map rendering to be performed in parallel with a process which retrieves the data for the next map location the user will require. A viewdependent approach has been integrated to monitor the volume of each LoD for visible area. The demonstration of a exible rendering style shows its potential use in visualizing dynamic geoprocessed data. Future work may extend this to integrate topological constraints and semantic constraints for enhancing the vector map visualization

Polygon Processing on OpenStreetMap XML Data

Abstract included in text

Polygon Processing on OpenStreetMap XML Data

Abstract included in text

Agricultural trade between Malaysia and China: Competitiveness and complementarity

The discernment of trade competitiveness and complementarity findings holds crucial implications for policymakers, facilitating the formulation and implementation of strategies conducive to fostering economic growth. This study aims to determine the latest level of competitiveness and complementarity of the agricultural trade between Malaysia and China. This investigation uses quantitative research methodologies to draw upon data extracted from the UN Commodity Trade Statistics Database, specifically employing the HS2012 (HS12) classification system from 2017 to 2019. The empirical findings illuminate significant trends. China displays a pronounced comparative advantage in exporting agricultural products classified by HS12 items 05, 13, and 16, whereas Malaysia exhibits a pronounced comparative advantage in exporting HS12 items 14, 15, 18, 19, and 21. The examination of trade dynamics unveils that HS12 item 07 demonstrates a complementary relationship in terms of China’s exports and Malaysia’s imports, while HS12 items 14, 15, and 19 exhibit complementarity from the perspective of Malaysia’s exports and China’s imports. The trade intensity index (>1) substantiates the profound interconnectedness characterizing bilateral agricultural trade ties between the two nations. The investigation uncovers inter-industry advantages within HS12 items 06, 07, 11, 14, and 16, juxtaposed with intra-industry advantages specifically about HS12 item 23. The findings provide evidence of the inherent comparative advantages prevalent within diverse agricultural product categories. Consequently, this study not only aids policymakers but also furnishes traders within Malaysia and China with strategic insights, thereby facilitating the development of plans to augment the competitive prowess within their respective agricultural sectors

Student Modeling and Analysis in Adaptive Instructional Systems

There is a growing interest in developing and implementing adaptive instructional systems to improve, automate, and personalize student education. A necessary part of any such adaptive instructional system is a student model used to predict or analyze learner behavior and inform adaptation. To help inform researchers in this area, this paper presents a state-of-the-art review of 11 years of research (2010-2021) in student modeling, focusing on learner characteristics, learning indicators, and foundational aspects of dissimilar models. We mainly emphasize increased prediction accuracy when using multidimensional learner data to create multimodal models in real-world adaptive instructional systems. In addition, we discuss challenges inherent in real-world multimodal modeling, such as uncontrolled data collection environments leading to noisy data and data sync issues. Finally, we reinforce our findings and conclusions through an industry case study of an adaptive instructional system. In our study, we verify that adding multiple data modalities increases our model prediction accuracy from 53.3% to 69%. At the same time, the challenges encountered with our real-world case study, including uncontrolled data collection environment with inevitably noisy data, calls for synchronization and noise control strategies for data quality and usability

Mast Cells Modulate Acute Toxoplasmosis in Murine Models

The role of mast cells (MCs) in Toxoplasma gondii infection is poorly known. Kunming outbred mice were infected intraperitoneally with RH strain T. gondii, either treated with compound 48/80 (C48/80, MC activator) or disodium cromoglycate (DSCG, MC inhibitor). Compared with infected controls, infected mice treated with C48/80 exhibited significantly increased inflammation in the liver (P \u3c 0.01), spleen (P \u3c 0.05), and mesentery (P \u3c 0.05) tissues, higher parasite burden in the peritoneal lavage fluids (P \u3c 0.01), and increased levels of mRNA transcripts of T. gondii tachyzoite surface antigen 1 (SAG1) gene in the spleen and liver tissues (P \u3c 0.01), accompanied with significantly increased Th1 cytokine (IFN-γ, IL-12p40, and TNF-α) (P \u3c 0.01) and decreased IL-10 (P \u3c 0.01) mRNA expressions in the liver, and increased IFN-γ (P \u3c 0.01) and IL-12p40 (P \u3c 0.01) but decreased TNF-α (P \u3c 0.01) and IL-4 (P \u3c 0.01) in the spleens of infected mice treated with C48/80 at day 9-10 p.i. Whereas mice treated with DSCG had significantly decreased tissue lesions (P \u3c 0.01), lower parasite burden in the peritoneal lavage fluids (P \u3c 0.01) and decreased SAG1 expressions in the spleen and liver tissues (P \u3c 0.01), accompanied with significantly increased IFN-γ (P \u3c 0.01) and IL-12p40 (P \u3c 0.05) in the liver, and decreased IFN-γ (P \u3c 0.05) and TNF-α (P \u3c 0.01) in the spleens; IL-4 and IL-10 expressions in both the spleen and liver were significantly increased (P \u3c 0.01) in the infected mice treated with DSCG. These findings suggest that mediators associated with the MC activation may play an important role in modulating acute inflammatory pathogenesis and parasite clearance during T. gondii infection in this strain of mice. Thus, MC activation/inhibition mechanisms are potential novel targets for the prevention and control of T. gondii infection

Tourism experiences reduce the risk of cognitive impairment in the Chinese older adult: A prospective cohort study

Background: Given the etiological complexity of cognitive impairment, no effective cure currently exists for precise treatment of dementia. Although scholars have noted tourism’s potential role in managing cognitive impairment and mild dementia, more robust empirical investigation is needed in this area. This study aimed to examine the associations between tourism and cognitive impairment and dementia in older Chinese adults. Method: From a nationwide community-based cohort, 6,717 individuals aged ≥ 60 were recruited from 2011 to 2014, of whom 669 (9.96%) had had at least one tourism experience in the 2 years prior to enrollment. All the participants were then prospectively followed up until 2018. The association between tourism and cognitive impairment was examined by the Cox proportional hazards regression model. The adjusted hazard ratio (aHR) and its 95% confidence interval (CI) were calculated to evaluate the effect of tourism experience on cognitive impairment and dementia. Results: A total of 1,416 individuals were newly diagnosed with cognitive impairment and 139 individuals with dementia onset during follow-up. The incidence of cognitive impairment was significantly lower among participants with tourism experiences (316.94 per 10,000 person-years) than those without such experiences (552.38 per 10,000 person-years). Cox regression showed that tourism decreased the risk of cognitive impairment (aHR = 0.69, 95% CI: 0.41–0.62) when adjusted for behavioral covariates and characteristics. Compared with participants without tourism experiences, those with 1, 2, and ≥ 3 tourism experiences had a lower risk of cognitive impairment with the aHRs of 0.72 (95% CI: 0.52–0.99), 0.65 (0.42–1.01), and 0.68 (0.44–0.98), respectively. Tourism experiences also reduced participants’ risk of dementia (aHR = 0.41, 95% CI: 0.19–0.89). Conclusion: Our findings demonstrated associations between tourism and reduced risks of cognitive impairment and dementia in older Chinese adults. Thus, tourism could serve as a novel approach to dementia prevention

Management of spatial data for visualization on mobile devices

Vector-based mapping is emerging as a preferred format in Location-based Services(LBS), because it can deliver an up-to-date and interactive map visualization. The Progressive Transmission(PT) technique has been developed to enable the ecient transmission of vector data over the internet by delivering various incremental levels of detail(LoD). However, it is still challenging to apply this technique in a mobile context due to many inherent limitations of mobile devices, such as small screen size, slow processors and limited memory. Taking account of these limitations, PT has been extended by developing a framework of ecient data management for the visualization of spatial data on mobile devices. A data generalization framework is proposed and implemented in a software application. This application can signicantly reduce the volume of data for transmission and enable quick access to a simplied version of data while preserving appropriate visualization quality. Using volunteered geographic information as a case-study, the framework shows exibility in delivering up-to-date spatial information from dynamic data sources. Three models of PT are designed and implemented to transmit the additional LoD renements: a full scale PT as an inverse of generalisation, a viewdependent PT, and a heuristic optimised view-dependent PT. These models are evaluated with user trials and application examples. The heuristic optimised view-dependent PT has shown a signicant enhancement over the traditional PT in terms of bandwidth-saving and smoothness of transitions. A parallel data management strategy associated with three corresponding algorithms has been developed to handle LoD spatial data on mobile clients. This strategy enables the map rendering to be performed in parallel with a process which retrieves the data for the next map location the user will require. A viewdependent approach has been integrated to monitor the volume of each LoD for visible area. The demonstration of a exible rendering style shows its potential use in visualizing dynamic geoprocessed data. Future work may extend this to integrate topological constraints and semantic constraints for enhancing the vector map visualization

Management of spatial data for visualization on mobile devices

Vector-based mapping is emerging as a preferred format in Location-based Services(LBS), because it can deliver an up-to-date and interactive map visualization. The Progressive Transmission(PT) technique has been developed to enable the ecient transmission of vector data over the internet by delivering various incremental levels of detail(LoD). However, it is still challenging to apply this technique in a mobile context due to many inherent limitations of mobile devices, such as small screen size, slow processors and limited memory. Taking account of these limitations, PT has been extended by developing a framework of ecient data management for the visualization of spatial data on mobile devices. A data generalization framework is proposed and implemented in a software application. This application can signicantly reduce the volume of data for transmission and enable quick access to a simplied version of data while preserving appropriate visualization quality. Using volunteered geographic information as a case-study, the framework shows exibility in delivering up-to-date spatial information from dynamic data sources. Three models of PT are designed and implemented to transmit the additional LoD renements: a full scale PT as an inverse of generalisation, a viewdependent PT, and a heuristic optimised view-dependent PT. These models are evaluated with user trials and application examples. The heuristic optimised view-dependent PT has shown a signicant enhancement over the traditional PT in terms of bandwidth-saving and smoothness of transitions. A parallel data management strategy associated with three corresponding algorithms has been developed to handle LoD spatial data on mobile clients. This strategy enables the map rendering to be performed in parallel with a process which retrieves the data for the next map location the user will require. A viewdependent approach has been integrated to monitor the volume of each LoD for visible area. The demonstration of a exible rendering style shows its potential use in visualizing dynamic geoprocessed data. Future work may extend this to integrate topological constraints and semantic constraints for enhancing the vector map visualization

Management of spatial data for visualization on mobile devices

Vector-based mapping is emerging as a preferred format in Location-based Services(LBS), because it can deliver an up-to-date and interactive map visualization. The Progressive Transmission(PT) technique has been developed to enable the ecient transmission of vector data over the internet by delivering various incremental levels of detail(LoD). However, it is still challenging to apply this technique in a mobile context due to many inherent limitations of mobile devices, such as small screen size, slow processors and limited memory. Taking account of these limitations, PT has been extended by developing a framework of ecient data management for the visualization of spatial data on mobile devices. A data generalization framework is proposed and implemented in a software application. This application can signicantly reduce the volume of data for transmission and enable quick access to a simplied version of data while preserving appropriate visualization quality. Using volunteered geographic information as a case-study, the framework shows exibility in delivering up-to-date spatial information from dynamic data sources. Three models of PT are designed and implemented to transmit the additional LoD renements: a full scale PT as an inverse of generalisation, a viewdependent PT, and a heuristic optimised view-dependent PT. These models are evaluated with user trials and application examples. The heuristic optimised view-dependent PT has shown a signicant enhancement over the traditional PT in terms of bandwidth-saving and smoothness of transitions. A parallel data management strategy associated with three corresponding algorithms has been developed to handle LoD spatial data on mobile clients. This strategy enables the map rendering to be performed in parallel with a process which retrieves the data for the next map location the user will require. A viewdependent approach has been integrated to monitor the volume of each LoD for visible area. The demonstration of a exible rendering style shows its potential use in visualizing dynamic geoprocessed data. Future work may extend this to integrate topological constraints and semantic constraints for enhancing the vector map visualization