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Driven by foundation models, recent progress in AI and machine learning has reached unprecedented complexity. For instance, the GPT-3 language model consists of 175 billion parameters and a training-data size of 570 GB. While it has achieved remarkable performance in generating text that is difficult to distinguish from human-authored content, a single training of the model is estimated to produce over 550 metric tons of CO2 emissions. Likewise, we see advances in GeoAI research improving large-scale prediction tasks like satellite image classification and global climate modeling, to name but a couple. While these models have not yet reached comparable complexity and emissions levels, spatio-temporal models differ from language and image-generation models in several ways that make it necessary to (re)train them more often, with potentially large implications for sustainability. While recent work in the machine learning community has started calling for greener and more energy-efficient AI alongside improvements in model accuracy, this trend has not yet reached the GeoAI community at large. In this work, we bring this issue to not only the attention of the GeoAI community but also present ethical considerations from a geographic perspective that are missing from the broader, ongoing AI-sustainability discussion. To start this discussion, we propose a framework to evaluate models from several sustainability-related angles, including energy efficiency, carbon intensity, transparency, and social implications. We encourage future AI/GeoAI work to acknowledge its environmental impact as a step towards a more resource-conscious society. Similar to the current push for reproducibility, future publications should also report the energy/carbon costs of improvements over prior work.

Objective To explore whether inhibiting autophagy can enhance the sensitivity of photothermal treatment under mild photothermal conditions. Methods CQ@PLGA@PDA NPs were prepared by an improved double emulsification method and a PDA-based surface modification method. After basic characterization, CCK-8 method was used to detect the cytotoxicity of nanoparticles; the near-infrared laser irradiation nanoparticle solution was used to detect the heating effect; CCK-8 method and live-dead cell staining were used to detect the killing effect of tumor cells; Western blot was used to detect the expression of autophagy-related proteins. Results The CQ@PLGA@PDA NPs were successfully prepared, with a particle size of 253.10±2.39 nm, a zeta potential of -22.57±0.80 mV, uniform particle size and good dispersion. The temperature of nanoparticle solution increased to 45℃ after the near-infrared laser irradiation for 10 min. CQ@PLGA@PDA NPs had no obvious toxicity to cells. The survival rates of breast cancer cell MDA-MB-231 and mouse embryonic fibroblast NIH-3T3 cell were above 95%. The inhibition of autophagy under mild photothermal conditions could improve the sensitivity of photothermal therapy. Conclusion The prepared CQ@PLGA@PDA NPs have good photothermal performance and high biological safety; by inhibiting autophagy, they can effectively kill tumor cells under mild photothermal conditions(< 50℃).

One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge Graphs: New Directions for Knowledge Representation on the Semantic Web" and described in its report is that of a: "Public FAIR Knowledge Graph of Everything: We increasingly see the creation of knowledge graphs that capture information about the entirety of a class of entities. [...] This grand challenge extends this further by asking if we can create a knowledge graph of "everything" ranging from common sense concepts to location based entities. This knowledge graph should be "open to the public" in a FAIR manner democratizing this mass amount of knowledge." Although linked open data (LOD) is one knowledge graph, it is the closest realisation (and probably the only one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides a unique testbed for experimenting and evaluating research hypotheses on open and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing evolution and long term preservation. We want to investigate this problem, that is to understand what preserving and supporting the evolution of KGs means and how these problems can be addressed. Clearly, the problem can be approached from different perspectives and may require the development of different approaches, including new theories, ontologies, metrics, strategies, procedures, etc. This document reports a collaborative effort performed by 9 teams of students, each guided by a senior researcher as their mentor, attending the International Semantic Web Research School (ISWS 2019). Each team provides a different perspective to the problem of knowledge graph evolution substantiated by a set of research questions as the main subject of their investigation. In addition, they provide their working definition for KG preservation and evolution.

One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge Graphs: New Directions for Knowledge Representation on the Semantic Web" and described in its report is that of a: "Public FAIR Knowledge Graph of Everything: We increasingly see the creation of knowledge graphs that capture information about the entirety of a class of entities. [...] This grand challenge extends this further by asking if we can create a knowledge graph of "everything" ranging from common sense concepts to location based entities. This knowledge graph should be "open to the public" in a FAIR manner democratizing this mass amount of knowledge." Although linked open data (LOD) is one knowledge graph, it is the closest realisation (and probably the only one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides a unique testbed for experimenting and evaluating research hypotheses on open and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing evolution and long term preservation. We want to investigate this problem, that is to understand what preserving and supporting the evolution of KGs means and how these problems can be addressed. Clearly, the problem can be approached from different perspectives and may require the development of different approaches, including new theories, ontologies, metrics, strategies, procedures, etc. This document reports a collaborative effort performed by 9 teams of students, each guided by a senior researcher as their mentor, attending the International Semantic Web Research School (ISWS 2019). Each team provides a different perspective to the problem of knowledge graph evolution substantiated by a set of research questions as the main subject of their investigation. In addition, they provide their working definition for KG preservation and evolution.

Jingjing Li,1,2,* Jia You,2,3,* Chen Wu,2 Yue Dai,1 Meilin Shi,2 Lina Dong,2 Kai Xu1,2 1Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221006, People’s Republic of China; 2School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, People’s Republic of China; 3Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, People’s Republic of China *These authors contributed equally to this work Background: The development of T1–T2 dual contrast agent (CA) favors the visualization of the lesion in a more accurate and reliable manner by magnetic resonance imaging (MRI). The relaxivity and the interference between T1 and T2 CA are the main concerns for their design. Methods: In this work, we constructed an Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex where BSA-Gd2O3 NPs and Fe3O4 NPs were chosen as T1 and T2 MRI CAs and a 20nm mesoporous silica (mSiO2) nanoshell was introduced to reduce the interference between them. We performed transmis­sion electron microscopy, X-ray powder diffraction, UV-vis absorption spectra, and Fourier transform infrared absorption (FTIR) spectra to characterize the prepared nanocomplex and MRI scanning to evaluate their MRI behaviors. Furthermore, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and hematologic and biochemical analyses were introduced to evaluate their in vitro and in vivo toxicity. Finally, the specific MRI of 786-0 cells with Fe3O4@mSiO2/PDDA/BSA-Gd2O3-AS1411 nanoprobe invitro was realized. In vivo biodistribution of Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex in the mouse was determined by the quantification of the Gd element by inductively coupled plasma-mass spectrometry. Results: The prepared Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex possessed high longitudinal (r1=11.47 mM s-1 Gd) and transverse (r2=195.1 mM s-1 Fe) relaxivities, enabling its use as a T1–T2 dual contrast agent for MRI. MTT testing and hematologic and biochemical analysis indicated the good biocompatibility of Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex in vitro and invivo. After further conjugation with AS1411 aptamer, they could target tumor cells successfully by T1 and T2 MRI in vitro. The possible metabolic pathway of the tail vein-injected Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex in mouse was mainly via kidney. Conclusion: A T1–T2 dual-mode contrast agent, Fe3O4@mSiO2/PDDA/BSA-Gd2O3 nanocomplex, was developed and its good performance for tumor cell targeting in vitro and kidney contrast-enhanced MRI in mice indicated its promising potential as an effective T1–T2 dual-mode contrast agent for in vivo MRI with self-confirmation. Keywords: molecular magnetic resonance imaging, nano-contrast agent, aptamer, T1–T2, MRI

Concurrency control has always been one of the most important issues in the design of synchronous groupware systems with fully-replicated architecture. An ideal strategy should be able to support natural and flexible human-to-computer and human-to-human interactions while maintaining the consistency of the system. This paper summarizes previous researches on this topic and points out the deficiencies of the existing results. A novel semantics-based concurrency control framework,oodOPT, is proposed. The main idea of the framework is to resolve conflicts by utilizing semantics of the operations and the accessed data objects. With this approach, complexities in concurrency control are shifted completely from application developers to the framework. Conflicts among operations on objects with different semantics and the strategies resolving these conflicts are analyzed. After describing the algorithm in full detail, the discussion ends up with a comparison with other related work and some considerations for open problems.

This paper proposes a knowledge-based specification technique (KST) for protocol development. This technique semi-automatically translates a protocol described in an informal description (natural languages or graphs) into one described in formal specifications (Estelle and SDL). The translation processes are supported by knowledge stored in the knowledge base. This paper discusses the concept, the specification control mechanism of KST and the rules and algorithms for production of FSM's which is the basis of Estelle and SDL.

In the vehicle communication system based on ADHOC network, besides fairness, QoS, hidden and exposed terminal problems, the MAC protocol must fulfill the requirement of practical applications. In order to decrease the transmission collisions in VANETs, a reliable and efficient medium access control (MAC) protocol is needed. Firstly, this paper introduces the applications, the characteristics of VANETs, and the difficulties of MAC protocols in VANETs. Secondly, based on different reactive routing protocols, various MAC protocols (wireless LAN and Adhoc MAC) applied to VANETs are theoretically compared and analyzed for sub-urban, urban, and freeway situations. A qualitative comparison of VANETs MAC protocols were given. Finally, the goals and the design essentials of transmission control in VANET are proposed.

While data and path redundance avoids, to some extent, data damages and mission failures resulting from node failures in networks, users must face up to the great challenge of Quality of Service(QoS), i.e., how to select optimal data sources and paths among different data sources. We address ourselves to the problem of Multiple Data Sources Selection(MDSS) for data sharing and propose a precomputation algorithm, namely PAMDSS. PAMDSS decomposes MDSS into two sub-problems, and introduces the concept of Pareto optimization which reduces the search space greatly. By means of nonlinear path length based precomputation, PAMDSS achieves good QoS effects. Extensive simulations show the efficiency of our algorithm.

This paper presents a knowledge empowered automated negotiation system for buyer-centric multi-bilateral multi-attribute e-Procurement. We propose two knowledge empowered models namely KERM and KACM. KERM is used for the buyer to determine a list of suppliers which are the best qualified candidates to negotiate with. KERM also allows the flexibility to assign appropriate weights, based on buyer's interests, to each knowledge factor affecting the overall evaluation result of a quote. The resulted list of quotes of high rank is believed to produce satisfactory negotiation result for the buyer. KACM enables an automated concession process, while at the same time facilitates a flexible negotiation via the use of concept switch and tagged rules. KACM emphasizes the utilization of knowledge originated from the historical negotiation data in estimating and fine-tuning the negotiation parameters for improving the performance of automated negotiation. Our results show that the prototype makes significant improvement in the satisfaction level of negotiation results.

Mobile Ad-hoc networks (MANETs) are non-infrastructure networks which consist of mobile nodes equipped with limited battery. In order to use energy efficiently, several energy consuming balance routing protocols have been proposed. These approaches use various metrics related to residual battery capacity in routing metric, but do not take the channel busy ratio into concerns. In this paper, we propose a novel routing protocol, called Busy-zone Avoidable Energy consume Balance Routing (BAEBR), combining the nodes' residual energy, channel busy ratio and hop counts together. Considering the mobility, we preferred on-demand routing protocol, and implemented based on the improvement of Ad hoc on demand Distance Vector (AODV) protocol. Simulation results show that there are about 10% improvement on total delivered packets and delivery ratio at the same time control the packet delay.

To automate the agent negotiation process, it has been widely accepted that two important tasks must be done: (1) formalize the negotiation process, and (2) incorporate necessary negotiation knowledge and intelligence. However, due to the fuzzy and complex nature, the lack of knowledge interoperability and knowledge-reuse in most agent-based services deployed has posed certain drawback to automated negotiation. An object-oriented ontology-based building block for knowledge representation, namely, knowledge bead (KB), has been proposed in (S. Fong, et al., 2002). It was designed as a foundation to enable automated agent negotiation in e-trading environment in a systematic way. This paper features the research work of KB on constructing its taxonomy and methodology, and the use of the knowledge carried by KB's in automated negotiation process. We anticipate the more efficient electronic commerce achieved with the support of the knowledge-empowered agent negotiation

With the development of network technologies, data management systems are required to work under distributed, heterogeneous and autonomous environments. Computer supported cooperative work (CSCW) provides an improved method to manage data comparing with current database management systems. In this paper, we generally describe the traditional multi-database management systems at first. Then, by introducing the idea of cooperative, an agent supported data management under cooperative environment (CoDMS) is developed to meet the requirement of cooperative applications. The intercommunicating and cooperating between users and databases is solved by using cooperative agents.

Large-scale cooperation support for learners becomes even more important, when e-Learning is implemented in scalable, open, dynamic and heterogeneous environment. We have designed grid architecture and implemented grid middleware and higher CSCW services for establishing collaborative platform for e-Learning. A Learning Assessment Grid, abbreviated as LAGrid, is built on top of these services. This paper introduces the layered LAGrid architecture and presents how to implement grid middleware to support collaborative platform for e-Learning using Web services technologies. The work shows service-oriented grid middleware layer provides a good middleware platform for collaborative applications in large-scale cross-organization environment.

Widespread attacks involving multiple hosts/networks happen more frequently as internetworking among computer systems via the Internet becomes more widely and keeps rapid increase. Due to lack of information, it can be quite difficult for conventional intrusion detection systems to identify such attacks in progress. Cooperative intrusion detection, on the basis of information sharing, is proved as a necessary measure to detect widespread attacks by other researcher D. Frincke (2000), Polla, D. et al., (1998). This paper presents a cooperative approach for intrusion detection that provides a method for individual ID components working cooperatively to perform concerted detections. Being constructed on the basis of ID components, CoIDS can adopt both existed (usually more mature) and new ID techniques. This makes CoIDS extensible and scalable. In addition, an ID component is essentially an autonomous agent, which makes CoIDS available with certain loss of functionality even when the intrusion detection manager does not work. Its reliability is also improved because failure of one ID component will not cause any other to stop working. Furthermore, it improved the accuracy of detection for conventional intrusions by validating analysis result with data from different ID components.

The technology of using computer Agents for B2B trading in Cyberworld is getting prevalent nowadays. Much of the research work has been done on the models, architectures and service provision in the past. However, agent negotiation remains as a challenge in making the whole trading process fully automated, due to its fuzzy and complex nature. The lack of interoperability and knowledge-reuse that limits to case-based, pose certain drawback. An object-oriented ontology-based Knowledge Bead (KB) method for knowledge representation has been proposed (S. Fong et al., 2002). It was designed as a foundation to enable agent negotiation in e-trading environment in a systematic way. This paper continues the research work of KB on formulating its theorems and methodology. Some typical negotiation paradigms using appropriate strategies based on the KB's methodology are presented as well. In particular, KB's taxonomies and their use in the whole negotiation process are discussed. The main advantage of this approach is the ability to describe the deal that is under negotiation in an object-oriented format which in turn allows reasoning, optimizing, knowledge reuse and management.

Online negotiation for today's B2B e-commerce plays a promising role in assisting traders to best fulfill their business deals. But existing uncertain constraints and sophisticated strategies presented in e-trading environment make negotiation a rather complex process. As business intelligence and efficient protocols are essential to successful negotiation, we defined an object-oriented ontology knowledge bead (KB) for knowledge representation and enabling agent negotiation in e-trading environment [S. Fong et al. (2002)]. We continue the research work of KB on formulating its theorems and methodology. Some typical negotiation paradigms using appropriate strategies based on the KB's methodology are presented. In particular, KB's taxonomies and their use in the negotiation process are discussed.

The objective is to design an agent-based B2B trading system that has both the dynamic negotiation ability and knowledge management functionality. Achieving both agent negotiation and knowledge management (KM) is believed to be possible when the "knowledge" that is used to describe the product and the deal are commonly represented by an object-oriented ontology called Knowledge Bead (KB) [S. Fong, et al. (2002)]. We focus on the knowledge context of agent negotiation process in electronic marketplace, discuss how knowledge can be formulated and managed, and further be utilized to assist in the competent negotiation process. This is the continued research work on knowledge beads [S. Fong, et al. (2002)][Z. Yan, et al. (2003)]. The anticipated contribution will be a clearer understanding on knowledge management utilization for intelligent negotiation in electronic commerce.

CSCW (computer supported cooperative work) has been a promising research field in recent years. CSCW is based on interdisciplinary principles, and it promotes the alternation from traditional isolated work to group cooperative work. The paper introduces the basic background of CSCW. A computer conferencing system belongs to real-time CSCW application and is one of the most significant parts in the CSCW research field. The paper analyzes the functional requirement for desktop computer conferencing system. Then the author describes a full schematic software design for a desktop computer conferencing system, and explains the strategies adopted in the design. In this design, the author also advances a client-server model for multimedia synchronization. Finally, the paper presents some prospects on future work.

The protocol conformance test system (PCTS) is the principal facility used to verify the conformance between the communication protocol implementation and its international standard. We first discuss the importance and function of reference implementation (RI) in the PCTS, and give a general abstract model of the RI with the method of object-oriented design (OOD). After introducing the UNIX STREAMS mechanism, we present the basic abstract model for developing the RI in a UNIX kernel, and introduce the IP/X25 RI, which is implemented with this model, as a example.

As research and development on CSCW advance rapidly, there is an increasing need for a general purpose platform based on which various types of CSCW applications can be developed. The platform should provide not only necessary services that minimize development efforts, but also sufficient flexibility for the construction of applications. This paper describes DICSE, a platform providing data management services based on the characteristics of data flow in CSCW systems, detailing its underlying cooperative work model, the services, the architecture and some considerations for the implementation.

Workflow management systems can help business goals to be achieved with high efficiency by means of sequencing work activities and invoking appropriate human and/or information resources associated with these activities. As computer networks are used more and more widely in daily work, workflow management attracts more and more attention from both industry and research communities. This paper summarizes the state of art in WfMS research, detailing some workflow-related concepts and its typologies, the WfMS reference model proposed by WfMC, and some of the current research trends and hotspots.

With the Internet and "information highway" being established, CSCW finds a new application. We first discuss the three fields of the combination of CSCW and the Internet, and then illustrate how to apply the cooperation effects to the Internet and make the Internet elements, including cache servers and Web servers, work cooperatively, to improve the functionality of the Internet. For cache cooperation, the cooperation mechanism and cooperation scheme are discussed in detail, while for the Web servers, we discuss the cooperation policy.

The self-organized network consists of mobile radio nodes (hosts, routers or switches), self-forming a temporary network, without any aid from existing infrastructure or centralized system administration. Designing a self-organized networking system is a real challenge, which mainly stems from three aspects: dynamic topology, lack of centralized entities, internetworking. To meet this challenge, the Computer Network and CSCW Laboratory in Tsinghua University proposes the wireless mobile router, designed to organize the self-organized network system. This paper describes the logical structure of self-organized network, presents the hardware architecture, the software architecture, as well as the main protocols of the wireless mobile router.

A self-organized network is a kind of wireless network that can be deployed instantly and provide easy network communication without the support of pre-established network infrastructures, such as base stations. This network architecture brings promise of much better mobility and communication capacity. Various routing protocols have been presented. This paper gives a detailed study of whether each of them works and whether there is a superior one that can function successfully under all kinds of situations. We conclude that there is no superior protocol for all situations and look at the main issues to be considered when designing routing protocols for a self-organized network.

A self-organized network is a multi-hop temporary autonomous system of mobile nodes with wireless transmitters and receivers but without a preestablished network infrastructure. In such an environment, it may be necessary for one mobile node, in order to communicate with another node, to depend on a chain of intermediate nodes to forward packets, due to the limited propagation range of each mobile node. Conventional routing protocols can not adapt well to such an environment. For finding and maintaining the routes, this paper proposes a distributed adaptive routing protocol which is most likely to meet QoS requirements. It is based on two characteristics: average bit error rate and life time.

A converged network tries to merge existing PSTN, CATV networks and computer networks into one unitary network. It makes better use of network resources, provides new kinds of services, and brings great effect and profit in the fields of both economy and society. This paper proposes a novel LAN-based IP telephone system that merges traditional PSTN and computer networks together to meet the demands of the next-generation converged network. The design of its architecture, system management server (SMS), Internet-PSTN gateway, and digital terminals are presented. With this approach, the traditional telephone service can be provided on LAN. Therefore, the redundancy in constructing both computer networks and PSTN can be avoided. The system can also make more efficient use of the bandwidth and provide some novel value-added services that are very useful.

The goal of a CSCW system is to enable users to cooperate conveniently no mater when and where. Currently, most CSCW users rely on the existing network infrastructures. The self-organized network is a multi-hop temporary autonomous system of mobile nodes equipped with wireless transmitters and receivers without the aid of any existing network infrastructure. In such an environment, it may be necessary for one mobile node, in order to communicate another node, to need a chain of intermediate nodes to forward packets due to the limited propagation range of each mobile node's wireless transmissions. The self-organized networking can provide a communication supporting environment when the network infrastructure is absent, thus extending the CSCW application environment. This paper describes the conception and characteristics of the self-organized network, then proposes its architecture.

At present most workflow management systems independently manage workflows but ignore the resource constraint between them. A workflow management system based on agents can solve this problem effectively. This paper mainly discusses issues on workflow management based on agents including the configuration of the workflow system, dynamic scheduling of workflows, multi-agent system organization and communication.

Workflow management systems provide an ideal environment and a set of tools for enterprise-wide cooperation by automating business processes. An intelligent workflow management system should have the ability to analyze and re-engineer workflow process to improve performance and efficiency. There are two possible ways to do this: technology-based re-engineering and re-engineering based on relations between people or organizations. The latter forms the basic topics of business process re-engineering (BPR). This paper discusses workflow process re-engineering (WPR), which focuses on static analyzing of data flow and control flow of workflow definitions for process optimizing, so that system performance and cooperation efficiency can be improved while original intentions and executing results of the optimized process remain unchanged.

As the Internet/intranet/WWW technologies become more and more mature and Web-based applications become richer and richer, we are provided with an ideal computing environment to construct workflow management systems (WfMSs). Web-based WfMSs can help business goals to be achieved effectively by means of integrating various distributed resources and applications and coordinating work activities in an easy to access environment. This paper describes a Web-based general purpose workflow management system named Wowww!, detailing its architecture, the workflow engine, the workflow model and the algorithms used for workflow instance execution. Other features and some considerations for future work are also discussed.