• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.43-48
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• 2016

3-Dimensional System in Package (3-D SiP) structure (Amkor calls it mPossum-molded Possum) using double side Surface Mount Technology (SMT) and double side molding was evaluated in order to achieve small/thin form factor as well as good functionality by integration and double side layout. As the new platform on laminate substrate basis, molding process was challenge in mold flow balance at top and bottom side and package warpage control over the overall assembly process. There were two types of different molding process evaluated with 1) 1-step molding which was done at both side at the same time and 2) 2-step molding which was done at the conventional molding process twice. Mold simulation helped to narrow down the material selections and parameters available before actual sample build. There were many challenges for this first trial in design/ parameter and material types but optimized them to enable this structure.

• International journal of advanced smart convergence
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• v.9 no.1
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• pp.63-69
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• 2020

The rapid development in modern industrialization pollutant the water and atmospheric air across the globe that have a major impact on the human and livings health. In worldwide, every country government increasing the importance to improve the outdoor air pollution monitoring and control to provide quality of life and prevent the citizens and livings life from hazard disease. We proposed the environmental dust level detection method for outdoor facilities using sensor fusion technology to measure precise micro-dust level and monitor in realtime. In this proposed approach use the camera sensor and commercial dust level sensor data to predict the micro-dust level with data fusion method. The camera sensor based dust level detection uses the optical flow based machine learning method to detect the dust level and then fused with commercial dust level sensor data to predict the precise micro-dust level of the outdoor facilities and send the dust level informations to the outdoor air pollution monitoring system. The proposed method implemented on raspberry pi based open-source hardware with Internet-of-Things (IoT) framework and evaluated the performance of the system in realtime. The experimental results confirm that the proposed micro-dust level detection is precise and reliable in sensing the air dust and pollution, which helps to indicate the change in the air pollution more precisely than the commercial sensor based method in some extent.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.11
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• pp.1-9
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• 1999

As our society turns into the information age from the industrial one, the ministry of information and communication has set up functional software standards for electronic approval systems Several software houses have developed such systems in the client/server environment and subsequently for the intranet. Although electronic approval systems for the intranet have the advantages of less costly implementation and ease of use, they create heavy network traffic, and have a poor document processing functionality resulting from the lack of document processor in web environments. This paper describes a system design that web browsers utilize the resources of clients by adopting the ActiveX technique in order to improve such mallets mentions above. In other words, to use the Hangul word processor as a document processor, the ActiveX control and the Hangul DDE API have been implemented in the form of the DDE server/client, which is capable of mutual communication, and the flow of electronic approve system has been controled by connecting. As a result of running the implemented system lot three months through a real company in multi-server environment, it shows the high usage of electronic approval system as the tate roaches 75%-93% for some departments.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.5
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• pp.442-455
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• 2016

The resistance and seakeeping performance of a high-speed monohull vessel were investigated through a series of model tests in a towing tank. The hull had a slender wave-piercing bow, round bilge, and small deadrise angle on stern. Tests on the bare hull in calm water were first conducted and tests on spray rails followed. The spray rails were designed to control the flow direction and induce a hydrodynamic lift force on the hull bottom to reduce trim angle and increase rise of the hull. The maximum trim of the bare hull was $4.65^{\circ}$ at the designed speed, but the spray rails at optimum location reduced trim by $0.97^{\circ}$. The ship motion in head seas was examined after the calm water tests. Attaching the rails on the optimum location effectively reduced the pitch and heave motion responses. The vertical acceleration at the fore perpendicular reduced by 11.3%. The effective power in full scale was extrapolated from the model test results and it was revealed that the spray rails did not have any negative effects on the resistance performance of the hull, while they effectively stabilized the vessel in calm water and waves.

• Journal of the Korea Society of Computer and Information
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• v.19 no.3
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• pp.55-62
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• 2014

This paper has proposed Hybrid QoS Routing Link State Update(LSU) Algorithm that has had a both advantage of LSU message control in periodic QoS routing LSU algorithm and QoS routing performance in adaptive LSU algorithm. Hybrid LSU algorithm can adapt the threshold based network traffic information and has the mechanism that calculate LSU message transmission priority using the flow of statistical request bandwidth and available bandwidth and determine the transmission of the message according to update rate per a unit of time. We have evaluated the performance of the proposed algorithm and the existing algorithms on MCI simulation network using the performance metric as the QoS routing blocking rate and the mean update rate per link, it thus appears that we have verified the performance of this algorithm that it can diminish to 10% of the LSU message count.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1482-1504
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• 2007

An electrical railway system uses high voltage system for train traction and low voltage system for train control. Railway systems are broadly distributed across mountains, sea sides and cities. Electrical accidents provoke the death and injury of a human being and the damage of the equipment by the overcurrent due to the catenary dropping and by the overvoltage due to lightning. Grounding systems are adopted for the protections of the system from the overcurrent and the overvoltage. Isolation grounding for each system can be easily installed. However, the closed circuits between grounding systems can be occurred. The currents flow through the closed circuits cause the abnormal operation of the system. To overcome the problem of the isolation grounding, the equipotential bonding is usually adopted. The equipotential bonding should have very small grounding resistance. In this paper, we showed the transition from the isolation grounding system to the common grounding system and presented the comparison and the analysis of two grounding systems by simulation. In addition, we proposed the direction for a new grounding system of electric railway.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.2
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• pp.57-70
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• 2010

Purpose: In this study, we investigated the effects of GDB(Gidaebang) on the immune response to establish the treatment mechanism of vaginitis. Methods: We examined the effects of GDB on the DCs(Dendritic cells) phenotypic and functional maturation. iDCs were cultured in the presence of GM-CSF and the generated iDCs were respectively stimulated by GDB or LPS as the control group for 24 hours. To evaluate the DCs phenotypic and functional maturation, we used flow cytometric analysis, RT-PCR and ELISA. Results: 1. GDB upregulated the expression of class II MHC and CD40 on DCs. 2. GDB upregulated the expression of CD80 and CD86 on DCs. 3. GDB induced cytokine IL-12 production and mRNA expression in DCs. Conclusion: These results suggest that GDB is able to improve the antigen-presenting capacity of DCs through the upregulation of their maturation, and might induce proliferation of T cells. In conclusion, this immunomodulatory properties of GDB may be useful in the treatment of vaginitis.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.281-281
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• 2017

Recently, global warming by greenhouse gas effect is getting danger and danger for human life and agriculture at present. In Indonesia, according to heavy rain in the agriculture land is often covered by excess water in result crop growth would be affected negative. This water stress triggers roots failure in anaerobic condition for upland crop because of limiting roots respiration. Chili pepper grows in upland sometimes in touch with waterlogging due to rainfall and /or over flow water from river in Indonesia. In this case, roots growing is inhibited by effect of shortage of oxygen at root cap. Therefore, the objective of this study is to observe the plant behavior in waterlogging using mahor local genotypes (Ferosa, Laris, Romario) in Sumatra. The experiment was kept by at 1cm depth water above the soil surface as a waterlogged treatment for ---days. As a result, waterlogging affected plant growth of chili negatively, especially for roots growth. Almost roots were getting bad and changed color for brown during waterlogging. A significant negative effect for nutrient absorption by roots was found in dry weight of all varieties during waterlogging. Dry weight of roots was decreased by 81.4% and 67.6%, and those of aerial part decreased by 74% and 67.2% compared with control in Ferosa and Romario at 1week after treatment. On the other hand, dry weight of roots was decreased only 35% in Laris. Therefore, Laris has a tolerance for waterlogging compared to with other varieties. Also, Laris in SPAD value was kept initial level during waterlogging however those of Ferosa and Romario decreased. Finally, due to impact of waterlogging, it may be the roots become failure because of less aerenchyma formation under anaerobic condition. We need confirm aerenchyma formation morphologically in the future.

• Economic and Environmental Geology
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• v.39 no.5 s.180
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• pp.537-554
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• 2006

Water levels of thermal groundwater ($>30^{\circ}C$) were recorded from March 2002 to June 2006 at several monitoring wells within the Yuseong spa area. Using these data, we elucidated the long-term cyclic fluctuations of thermal groundwater levels with 1 year period. We also observed a noticeable water level variation with periods of 0.5, 1 and 7 days in most monitoring wells, which indicates relatively good hydraulic connectivity within the main hotspring area. By comparing water level variations among several wells, we found out that E-W and N-S trending geological structures should be an important control factor for emplacement and flow of thermal groundwater in the study area. It may be also inferred that geothermal source is highly associated with the hydraulic connectivity of aquifers at the Yuseong spa area.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3351-3369
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• 2017

In recent years, datacenters, network devices and computers have proliferated. The power consumed by information and communication technology (ICT) devices has inflated in an extraordinary manner. Green communication has emerged as a new approach to reduce and optimize power consumption in ICT sector. Many methods and protocols have been proposed and implemented to achieve green communication. Nevertheless, the increase of power consumption remains a problem. In this work, we attempt to reduce and optimize power consumption of network devices in datacenters environment utilizing software defined network (SDN) paradigm. To gain more insight of the power consumption requirements of network switches, a power measurement system is constructed to measure power consumption levels of network devices. Subsequently, we propose a duplication resolver algorithm (DRA) to power off/on switches reactively. DRA algorithm reduces the required time by switches to construct their flow tables after rebooting. To this end, DRA-based external circuit has been constructed utilizing Ethernet module and an Arduino kit to control power supplies of network devices. To facilitate our work, a testbed has been constructed utilizing Ryu SDN controller, HP2920-24G switches and Arduino kits. Our results show that DRA algorithm can reduce both the power usage and start-up time delay of network switches after failures.