• The Korean Journal of Nuclear Medicine Technology
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• v.28 no.1
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• pp.1-11
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• 2024

Hypoxia, defined as the deficiency of oxygen, is a significant hallmark of cancers presenting in the majority of solid tumors. Detection of tumor hypoxia is essential in cancer diagnosis to prevent cancer progression, metastasis, and resistance to cancer therapies in clinical practices. Single-photon emission computed tomography (SPECT) is one of the methods studied and applied for hypoxia detection with the use of radiolabeled imaging agents in which ^99mTc is the common radioisotope used for radiolabeling. Nitroimidazoles are the hypoxia-targeting moieties presenting in numerous ^99mTc-radiolabeled imaging agents due to their bio-reducible ability in hypoxic environments. Recently, in addition to ^99mTc-labeled radiopharmaceuticals containing one nitroimidazole unit, there has been considerable attention given to ^99mTc-radiopharmaceuticals bearing two or more nitroimidazole units. This review summarizes the synthesis of hypoxia-targeting chelators and radiolabeling processes to produce these ^99mTc-radiopharmaceuticals for SPECT imaging.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.194-205
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• 2006

The purpose of this study is to develop a pedestrian multi-agent model and simulation system using multi-agent theory, which may be utilized as a planning support system for building a comfort and safe environment of pedestrian street. Differing from existing pedestrian models, however, every single pedestrian was regarded as an individual agent in the model. Multiple agents like multiple pedestrians in the street then maintain their own characteristics and respond to surrounding environment. In addition their moving behavior are made by their own decision rules that they have or had acquired through the interactive communications or learning between agents like real world. After verifying the model validation, as the $R^2$ between the predicted value and observed value was up to 0.781, the developed model was applied to Gazwa district within Gyeongsang university village. The simulation system was developed by Flash MX action scripts and the physical environment of the streets was configured with the digital map and ArcGis within computer virtual space. The attribute data of buildings such as type and size of commercial business were collected through the field survey and combined with physical features. Then the effect of the variation of building attractiveness and the occurrence of street events to pedestrian environment were simulated. Through the experiments this study could make suggestions to improve pedestrian environment.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.10a
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• pp.99-102
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• 2000

In the supply chain network design, how to select the best location, capacity configuration of the suppliers and to assign manufacturers orders are a challenging issue. Especially when multi-tiers'suppliers are existed, the performance of supply chain is influenced by 2$\^$nd/ and 3$\^$rd/ suppliers. Supplier selection is multi-criteria problem which includes both qualitative and quantitative factors in supply chains. In order to select the best supplier it is necessary to make a trade off between these two factors such as cost, product quality, capacity, production lead time, deliver lead time and transportation lead tine of supplier constraints existed in multi-tiers supplier purchasing chain. In these circumstances, purchasing agents should decide two problems: which is the best supplier in each tier and how much should be purchased from each selected supplier. This research is intended to develop an integration of an analytical hierarchy process (AHP) and mathematical modeling proposed to consider two factors which may be conflicted in choosing the best supplier in each tier and placing the optimum order quantities to the supplier among multi-tiers suppliers.

• Journal of Internet Computing and Services
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• v.5 no.5
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• pp.69-77
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• 2004

As the internet is widely distributed. the intelligent search agent is commonly used to meet the needs of user. But these Intelligent multi-agents are so independent each other that they can not give reliability of information and also have difficulty in coping with the dynamic distributed environments due to the short of cooperation abilities among multiagent. To resolve these problems. this paper proposes the mechanism for efficient cooperation and information processing by creating agency within broker agent and clustering multi agent's agency using neural network. For reliability of information. we also propose the multiagent management mechanism that can improve the information update problems which are in existing search systems and evaluate the performance of this research through simulation.

• The Journal of Korean Association of Computer Education
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• v.7 no.1
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• pp.97-106
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• 2004

Recently, the demand for the customized courseware which is required from the learners is increased. Therefore the needs of the efficient and automated education agents in the web-based instruction are recognized. In this paper we propose a multi-agent system for course scheduling of learner-oriented using weakness analysis algorithm. At first proposed system analyze learner's result of evaluation and calculates learning accomplishment. From this accomplishment the multi-agent schedules the suitable course for the learner. The learner achieves an active and complete learning from the repeated and suitable course.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.8
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• pp.573-580
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• 2020

One of challengeable problems of multi-agent systems is a positioning control. Augmented Cucker-Smale model is using for controlling position and velocity of the multi-agent system. The original model applies same coefficients to all agents in same group, so that does not consider characteristic of each agent. To enhance performance of the original model, this paper transforms original coefficients to Mahalanobis distance coefficients that reflects an initial distribution of multi-agent systems and applies statistical degrees of freedom. This paper not only confirms tendency of enhanced performance of the suggested model by using monte-carlo simulation, but also additionally compares trajectory of the original model with the suggested model to confirm coefficients of Mahalanobis distance performing correctly.

• The Journal of Korea Robotics Society
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• v.2 no.3
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• pp.234-241
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• 2007

Effective tools which can alleviate the complexity and computational load problem in collision-free motion planning for multi-agent system have steadily been demanded in robotics field. To reduce the complexity, the extended collision map (ECM) which adopts decoupled approach and prioritization is already proposed. In ECM, the collision regions which represent the potential collision of robots are calculated using the computational power; the complexity problem is not resolved completely. In this paper, we propose a mathematical analysis of the extended collision map; as a result, we formulate the collision region as an equation with 5-8 variables. For mathematical analysis, we introduce realistic assumptions as follows; the path of each robot can be approximated to a straight line or an arc and every robot moves with uniform velocity or constant acceleration near the intersection between paths. Our result reduces the computational complexity in comparison with the previous result without losing optimality, because we use simple but exact equations of the collision regions. This result can be widely applicable to coordinated multi-agent motion planning.

• Restorative Dentistry and Endodontics
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• v.43 no.3
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• pp.29.1-29.13
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• 2018

Objectives: The aims of this study were to conduct a systematic review of the microtensile bond strength (${\mu}TBS$) of multi-mode adhesives to dentin and to perform a meta-analysis to assess the significance of differences in the ${\mu}TBS$ of one of the most commonly used universal adhesives (Scotchbond Universal, 3M ESPE) depending on whether the etch-and-rinse or self-etch mode was used. Materials and Methods: An electronic search was performed of MEDLINE/PubMed, ScienceDirect, and EBSCOhost. Laboratory studies that evaluated the ${\mu}TBS$ of multi-mode adhesives to dentin using either the etch-and-rinse or self-etch mode were selected. A meta-analysis was conducted of the reviewed studies to quantify the differences in the ${\mu}TBS$ of Scotchbond Universal adhesive. Results: Only 10 studies fulfilled the inclusion criteria for the systematic review. Extensive variation was found in the restorative materials, testing methodologies, and failure mode in the reviewed articles. Furthermore, variation was also observed in the dimensions of the microtensile testing beams. The meta-analysis showed no statistically significant difference between the etch-and-rinse and self-etch modes for Scotchbond Universal adhesive (p > 0.05). Conclusions: Multi-mode 'universal' adhesives can achieve substantial bonding to dentin, regardless of the used modes (either etch-and-rinse or self-etch).

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2002.05a
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• pp.222-229
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• 2002

A value net is a business design that uses digital supply chain concepts to achieve both superior customer satisfaction and company profitability. In order to implement the value net model, information processing and distribution needs to occur in real time. Software agent technology is becoming popular due to the inherent characteristics of autonomy, distributedness and modularity. In this paper, we adopt agent technology to handle all real time decision process, making the value net model a complex multi-agent network of decision makers. For the agents to properly coordinate their respective activities we develop MAVN model, a Web-based multi-agent language grounded in the XML and Java.

• Journal of Intelligence and Information Systems
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• v.9 no.3
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• pp.1-21
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• 2003

In this research, we developed a Multi-Agent based Negotiation Support System to be able to increase the competitive power of a company in dynamic environment and correspond to various orders of customers by diffusion of electronic commerce. The system uses the agent technology that is being embossed as new paradigm in dynamic environment and flexible system framework. The multi-agent technology is used to solve these problems through cooperation of agent. The system consists of six sub agents: Mediator, manufacturability Analysis Agent, Process Planning Agent, Scheduling Agent, Selection Agent, Negotiation-strategy Building Agent. In this paper, the proposed Multi-Agent based Negotiation Support System takes aim at the automation of transaction process from ordering to manufacturing plan through the automation of negotiation that is the most important in order-taking transaction.