• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.101-115
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• 2005

We propose in this article a procedure for testing unit and fractional orders of integration, with the roots simultaneously occurring in the trend, the seasonal and the cyclical component of the time series. The tests have standard null and local limit distributions. However, finite sample critical values are computed, and several Monte Carlo experiments conducted across the paper show that the rejection frequencies against unit (and fractional) orders of integration are relatively high in all cases. The tests are applied to the UK consumption and income series, the results showing the importance of the roots corresponding to the trend and the seasonal components and, though the unit roots are found to be fairly suitable models, we show that fractional processes (including one for the cyclical component) may also be plausible alternatives in some cases.

• Journal of the Korea Society of Computer and Information
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• v.21 no.10
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• pp.107-114
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• 2016

In this paper, we propose the building method for the unified IoT service platform between the variety of legacy systems with the heterogeneous structures and the operating environments. To accommodate the structural diversity of legacy systems, we develop a virtual integrated structure and interface abstracting method. By this, the new platform can use the data sources of the legacy systems as if the data source is in the new platform. In a manner without modification of the legacy systems with performing minimum tasks, we proposes a model that can be integrated without affecting the availabilities of the legacy systems.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.948-950
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• 1999

In this paper, a monitoring system is desigend for a GPS/INS integration system. The function of the monitoring system is to acquire real-time data from system and displayed them. The monitoring system supervises the operation of navigation system. Visual C++ was used in the implementation. The performance of the monitoring system was verified through a real-time test for a GPS/INS Integration system which is composed of a GPS Receiver. IMU(Inertial Measurement Unit), NCU (Navigation Computer Unit)

• Journal of Aerospace System Engineering
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• v.1 no.1
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• pp.60-66
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• 2007

The importance of software development in the integration of an avionics system is continuously increasing. And we can expect enlarged soft ware portion in the system integration for the more intelligent, reliable, and automated avionics system. For an avionics system software development the selection of a real-time operating system and internal avionics data bus protocol is very important from the viewpoint of the integration with the system hardware. In this paper, we present current trend of an avionics system software development including software development methodology, software development process, and international software process assessment improvement model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.127-132
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• 2006

The Global Positioning System (GPS), Inertial Navigation System (INS) and Pseudolite (PL) technologies all play very important roles in navigation systems. As an independent navigation system, GPS can provide high precision positioning results which are independent of time. However, the performance will become unreliable when the system experiences high dynamics, or when the receiver is exposed to jamming or RF interference. In comparison to GPS, though INS is autonomous and provides good short-term accuracy, its use as a standalone navigation system is limited due to the time-dependent growth of the inertial sensor errors. PLs are ground-based transmitters that can transmit GPS-like signals. They have some advantages in that their positions can be determined precisely, and the Signal-to-Noise Ratios (SNR) are relatively high. Because their combined performance, in principle, overcomes the shortcomings of the individual systems, the integration of GPS, INS and PL is increasingly receiving attention from researchers. Depending on the desired performance vs complexity, system integration can be carried out at different levels, namely loose, tight and ultra-tight coupling. Compared with loose and tight integration, although it is more complex in terms of system design, ultra-tight integration will be the basis of the next generation of reliable and robust navigation systems. Its main advantages include improved performance under exposure to high dynamics, and jamming and RF interference mitigation. This paper presents an overview of the ultra-tight integration developments and discusses some of the challenging issues.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• v.6 no.1
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• pp.44-50
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• 2003

If the accelerometers are used in measuring the response, the absolute values of the velocity and displacement are not usually obtainable because their initial values are not accounted for in the integration of the acceleration response. A new dynamic response conversion algorithm of both the time domain and the frequency domain is proposed for the problem in estimating the displacement data by defining the transformed responses. In this algorithm, the displacement response can be obtained from the measured acceleration records by integration without requiring the knowledge of the initial velocity and displacement information. The applicability of the technique is tested by an example problem using the real bridge's superstructure under several cases of moving load. In the response conversion procedure of the frequency domain, the identified response according to the frequency can be estimated by changing over the limits of integration. If the reliability of the identified responses is ensured, it is expected that the proposed method for estimating the impact factor can be useful in the bridge's dynamic test. This method can be useful in those practical cases when the direct measurement of the displacement is difficult as in the dynamic studies of huge structure.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.184-188
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• 2009

To interactively share High Definition (HD)-quality visualization over emerging ultra-high-speed network infrastructure, several lossless and low-delay real-time media (i.e., uncompressed HD video and audio) transport systems are being designed and prototyped. However, most of them still rely on expensive hardware components. As an effort to reduce the building cost of system, in this paper, we propose the integration of both transmitter and receiver machines into a single bi-directional transport system. After detailed bottleneck analysis and subsequent refinements of embedded software components, the proposed integration can provide Real-time Transport Protocol (RTP)-based bi-directional transport of uncompressed HD video and audio from a single machine. We also explain how to interface the Gbps-bandwidth display output of uncompressed HD media system to the networked tiled display of 10240 $\times$ 3200 super-high-resolution. Finally, to verify the feasibility of proposed integration, several prototype systems are built and evaluated by operating them in several different experiment scenarios.

• Journal of Digital Convergence
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• v.13 no.2
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• pp.153-158
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• 2015

Biologists are pursuing genetics related researches that can provide the core information to understand a certain cancer or inherent diseases. However, biological experimentations can produce different results by the difference of various elements or environments at the time of experimentation and/or difference of interpretations. Therefore, currently existing research results can possibly provide different information. These inconsistency can be found through integration of gene information. Biologists can save their time and efforts to find certain gene information if the gene information is integrated without inconsistency. An efficient gene integration and augmentation scheme of gene information generated through different researches is introduced in this paper.

• Journal of Korea Port Economic Association
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• v.34 no.3
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• pp.183-200
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• 2018

This study empirically tests the presence of rational bubbles in the ship prices using time series data from October 1996 to April 2017. To detect the existence of ship prices' rational bubbles, we use integration and cointegration tests, which were proposed by Campbell and Shiller(1987) and Diba and Grossman(1988), for circumventing misspecification of ship price model and applying the bubble test to nonstationary time series. The result of integration test supports existence of tanker price's rational bubble. The co-integration test also shows that drybulk ship and containership prices have been overvalued relative to the market fundamental, drybulk and container freight rates, due to non-stationary rational bubbles. These results provide Korean shipping industry and authorities implications that anticyclical ship investment and long-term and steady fleet capacity expansion policy are needed.

• ETRI Journal
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• v.41 no.3
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• pp.396-407
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• 2019

Laser-assisted bonding (LAB) is an advanced technology in which a homogenized laser beam is selectively applied to a chip. Previous researches have demonstrated the feasibility of using a single-tier LAB process for 3D through-silicon via (TSV) integration with nonconductive paste (NCP), where each TSV die is bonded one at a time. A collective LAB process, where several TSV dies can be stacked simultaneously, is developed to improve the productivity while maintaining the reliability of the solder joints. A single-tier LAB process for 3D TSV integration with NCP is introduced for two different values of laser power, namely 100 W and 150 W. For the 100 W case, a maximum of three dies can be collectively stacked, whereas for the 150 W case, a total of six tiers can be simultaneously bonded. For the 100 W case, the intermetallic compound microstructure is a typical Cu-Sn phase system, whereas for the 150 W case, it is asymmetrical owing to a thermogradient across the solder joint. The collective LAB process can be realized through proper design of the bonding parameters such as laser power, time, and number of stacked dies.