This paper aims to integrate the previous models about mean object transfer latency in one framework and analyze the result through the computational experience. The analytical object transfer latency model assumes the multiple packet losses and the Internet of Things(IoT) environment including multi-hop wireless network, where fast re-transmission is not possible due to small window. The model also considers the initial congestion window size and the multiple packet loss in one congestion window. Performance evaluation shows that the lower and upper bounds of the mean object transfer latency are almost the same when both transfer object size and packet loss rate are small. However, as packet loss rate increases, the size of the initial congestion window and the round-trip time affect the upper and lower bounds of the mean object transfer latency.
In this paper, we propose a system that monitors and controls the environment of a server room in real-time based on IoT. Recently, as the information society has been maximized, the damage has been significant when the computer system is down. In particular, damage such as a fire in the server room leads to loss of data and data recovery becomes impossible. In order to reduce such damage, a node capable of real-time monitoring using an IoT system was proposed. In addition, we proposed a coordinator node that can collect and monitor node information. In order to verify that the proposed system works, we have developed software that can control node monitoring and air conditioning. As a result of the experiment, we confirmed that the proposed system detects fire and controls the air conditioner.
In this paper, an error tracking platform is designed for enhanced-reliable IOT system. The platform is designed to enhance reliability of IOT system by analysing additional informations(OS, Browser, Device) and by notifying error detection to developers. Especially, in the case of an error in the service which it is difficult for developers to recognize it, The platform also supports notification services through various communication media(Email, Slack, SMS). The common interface is designed to accommodate many languages(typescript, Swift, and Android) in the development process, and the interface allows users to analyze errors that occur on various platforms, including mobile/web/desktop applications. By presenting each error in groups through issues, developers can easily identify issues in the service. The visualizing function is included to recognize various error type by dashboard.
The purpose of this paper is to verify the differences of the effect of the support between the number of employment of those who have experienced employment and the unemployment period of those who have not experienced employment for the participants of the Jeollanam-do Youth Job Search Allowance Support Project. In addition, this study attempted to find out the ways to develop the system using the Internet of Things by figure out how to use the allowance, the field of help, the average investment time per day, the average monthly expenditure, the difficulties of job search activities, and the differences in the youth job search activities for the required programs. In this study, 602 people who participated in the Jeollanam-do Youth Job Search Allowance Support Project from February 19 to March 9, 2020 are surveyed. The collected data was processed using the SPSS 21.0 program. The research results are as follows. First, there was a difference in satisfaction according to the number of jobs employed. Second, there was a difference in the effectiveness according to the number of employment. Third, there was a difference in satisfaction according to the period of unemployment. Fourth, there was a difference in effectiveness according to the period of unemployment. In order to enhance the effectiveness of the youth job search allowance support project, the Edutech industry and technology that can share various information using the Internet of Things environment in the untact era must be improved together.
The cloud computing industry is regarded as a key element of the ICT industry and an important industry that will be a watershed for the future development of ICT industry. Korea has established the 1st~2nd cloud computing development basic plan to induce the growth of the cloud industry. However, the domestic information security guide provides technical vulnerability analysis criteria for Unix and Windows servers, DBMS, network equipment, and security equipment, but fails to provide vulnerability analysis criteria for hypervisors that are key elements of cloud computing. Organizations that have deployed cloud systems will be able to assist in vulnerability analysis using the criteria presented in this paper.
In this paper, we propose a SDN-based fog computing service mobility support scheme. Fog computing architecture has been attracted because it enables task offloading services to IoT(Internet of Things) devices which has limited computing and power resources. However, since static as well as mobile IoT devices are candidate service targets for the fog computing service, the efficient task offloading scheme considering the mobility should be required. Especially for the IoT services which need low-latency response, the new connection and task offloading delay with the new fog computing node after handover can occur QoS(Quality of Service) degradation. Therefore, this paper proposes an efficient service mobility support scheme which considers both task migration and flow rule pre-installations. Task migration allows for the service connectivity when the fog computing node needs to be changed. In addition, the flow rule pre-installations into the forwarding nodes along the path after handover enables to reduce the connection delay and service interruption time.
In the paper, we propose a system that measures various agricultural parameters that affect crop yield and monitors location information. According to an analysis by international organizations, 60% of the world's population lives on agriculture. In addition, 11% of the world's soil is used for growing crops. For this reason, agriculture plays an important role in national development. If a problem occurs in agriculture due to weather or environmental problems, it can be a problem for national development. In order to solve these problems, it is important to modernize agriculture using modern IoT technology. It is possible to improve the agricultural environment by applying IoT technology in agriculture to build a smart environment. Through such a smart environment, it is possible to increase the yield of agricultural products, reduce water waste, and prevent overuse of fertilizers. In order to verify the proposed system, an experiment was performed in a soybean cultivation farm. Experimental results showed that using the proposed system, the moisture in the cultivated soil can be automatically maintained at 40%.
The purpose of this study was to explore the experience of relational aggression that old users of institutions for seniors have, understanding what that experience means. In detail, the study tried to determine the nature of the experience through a structural description of what and how the elderly users experience relational aggression. For the purpose, this study made profound interviews with 7 elderly persons who sustained such aggression while using the seniors’ institution in Busan. In the interview, a non-structured questionnaire survey was conducted. Data were analyzed using Colaizzi’s phenomenological approach. As a result, the study identified 32 meanings of relational the experience which were in turn divided into 16 subjects, and 5 categories like ‘I who am powerless’, ‘I who am in an unmanned island’, ‘whirlwinds in my mind’, ‘I who send myself into the world’ and ‘I who am dwindling’. Based on this result, this research made practical suggestions for preventing relational aggression as mentioned above.
The Internet of Things (IoT) era, in which all items used in daily life are equipped with a network connection function, and they are closely linked to increase the convenience of life and work, has opened wide. Robots also need to develop according to the IoT environment. A use of new type of evolved fuzzy machine (EFM) for generating legged robot trajectory in IoT enviornmentms is discussed in this paper. Fuzzy system has been widely used for describing nonlinear systems. In fuzzy system, determination of antecedent and consequent structures of fuzzy model has been one of the most important problems. EFM is described which carries out evolving antecedent and consequent structure of fuzzy system for legged robot. To generate the robot trajectory, parameters of each structure in the fuzzy system are tuned automatically by the EFM. The results demonstrate the performance of the proposed approach for the legged robot.
The research status of endangered amphibians in Korea was mainly studied the life-cycle and distribution status of species from the 1980s to the early 2000s. Although a relatively diverse range of studies have been conducted on mackerels, studies on habitat prediction, analysis, change and management are insufficient. WEB, which provides biota information using location information in Korea, is a site operated by the National Bio Resource Center under the Ministry of Environment, but there is no information on endangered species and general species information has also been found to be very scantily. For this research, we secured a database of location information of Narrow-mouth frog, an endangered species, by combining literature and field research, and established a system by applying new technologies and open-based platform technologies that can be easily accessed by non-technical personnel of IT among IT technologies. The system was divided into administrator functions and user functions to prevent indiscriminate sharing of information through authentication procedures through user membership of users. The established system was authorized to show the distance between the current location and the location of the Narrow-mouth frog. Considering the ecological characteristics of the Narrow-mouth frog, which is an endangered species, a radius of 500m was marked to determine the habitat range. The system is expected to be applied to the legal system to change existing protected areas, etc. and to select new ones. It is estimated that practical reduction measures can be derived by utilizing the development plan for reviewing the natural environment. In addition, the deployed system has the advantage of being able to apply to a wide variety of endangered species by modifying the information entered.
Recently, the size of the IoT sensor has been decreased and the collecting direction of the IoT sensor for acquiring the data have been changed from 2D to 3D. It makes sensor structure complex. In the fabrication of the complex structure, 3D printing technology has more useful than traditional manufacturing technologies. Among 3D printing technologies, FDM (fused deposition modeling) is a candidate technology to fabricate a small IoT sensor because the price of the machine and the material is cheap. In the FDM process, a 3D shape is made by depositing the melted filament. Recently, the patent of FDM technology is expired and cheat machines are developed based on the open-source. In the FDM process, mechanical properties of a fabricated part is affected by a lots of factors such as the kind of material and process parameters. Among them, infill is affecting the mechanical properties and the production lead time as well. In this work, a new method to optimize the FDM process with the consideration of mechanical property and production lead time was proposed. To verify the method, the fabrications were performed with the different infill rates. The results of tensile tests were analyzed to verify the proposed method.