• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.32B no.12
• /
• pp.1545-1551
• /
• 1995

As the modern industrial processes become more complex, it is getting more difficult to model and control the processes. Naturally, an advanced type of DCS(Distributed Control System) with higher level functions is being sought. Advanced DCS is a DCS with advanced functions such as fault diagnosis, GPC(Generalized Predictive Control), NN(Neural Network), and Fuzzy Control. In this thesis, we have studied a fuzzy control algorithm for realizing an advanced DCS. Its algorithm is implemented in a form of function code which is a process control language, being used by the industrial engineers. To verify the realized function code of the fuzzy control, the function code is applied to a continuous casting process of the Pohang Iron & Steel Works in Kwangyang. The rules of the fuzzy control were collected via interviews of the field operators and their operation documents. Finally under a real-time operating system environment, usability of the function code of the fuzzy control is shown via simulation for the continuous casting process.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.31B no.8
• /
• pp.172-180
• /
• 1994

Implantable biotelemetry systems are indispensable tools not only in animal research but also in clinical medicine as such systems enable the acquisition of otherwise unavailable physiological data. We present the manufacture of CMOS IC and its system for implantable multichannel biotelemeter system. The internal circuits of this system are designed not only to achieve as multiple functions and low power dissipation as possible but also to enable continuous measurement of physiological data. Its main functions are to enable continuous measurement of physiological data and to accomplish on-off power swiching of an implantable battery by receiving appropriate commanc signals from an external circuit. The implantable circuits of this system are designed and fabricated on a single silicon chip using $1.5\mu$m n-well CMOS process technology. The total power dissipation of implantable circuits for a continuous operation was 6.7mW and for a stand-by operation was 15.2$\mu$ W. This system used together with approriate sensors is expected to contribute to clinical medicine telemetry system of measuring and wireless transmitting such significant physiological parameters as pressure pH and temperature.

• Korean Journal of Mathematics
• /
• v.27 no.2
• /
• pp.445-463
• /
• 2019

Let C[0, T] denote the space of continuous real-valued functions on [0, T]. On the space C[0, T], we introduce a Banach algebra of series of functions which are generalized Fourier-Stieltjes transforms of measures of finite variation on the product of simplex and Euclidean space. We evaluate analytic Feynman integrals of the functions in the Banach algebra which play significant roles in the Feynman integration theory and quantum mechanics.

• Bulletin of the Korean Mathematical Society
• /
• v.57 no.3
• /
• pp.751-762
• /
• 2020

We define the average of a set of continuous functions of two variables (surfaces) using the structure of the two-parameter Wiener space that constitutes a probability space. The average of a sample set in the two-parameter Wiener space is defined employing the two-parameter Wiener process, which provides the concept of distribution over the two-parameter Wiener space. The average defined in our work, called an average function, also turns out to be a continuous function which is very desirable. It is proved that the average function also lies within the range of the sample set. The average function can be applied to model 3D shapes, which are regarded as their boundaries (surfaces), and serve as the average shape of them.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.241-246
• /
• 2002

Usually vibration properties are obtained from frequency response functions or impulse response functions of a system. Since the contact type sensors can affect the characteristics of vibrating systems, the non-contact type sensors such as laser Doppler vibrometer (LDV) are being widely used. Currently researches are being carried out in terms of modal analysis using a scanning vibrometer. For the continuous scan; the Chebyshev demodulation (or polynomial) is apparently suggested to extract the mode shapes. With single frequency sinusoidal excitation, this approach is well fitted. In this research, the Chebyshev demodulation technique has been applied to the impact excitation case. The vibration of the tested structure is modeled using impulse response functions. The technique is also adopted to the random excitation case. In order to verify the technique, a simply supported beam was chosen as the test rig. The calculation modules are developed by using MATLAB$\^$(R)/ in WindowsNT$\^$(R)/ environment.

• Proceedings of the KSME Conference
• /
• 2004.04a
• /
• pp.756-761
• /
• 2004

The effects of two important numerical procedures on the high precision structural analysis are investigated in this study. The two numerical procedures include continuous variable approximation and time integration. For the continuous variable approximation, polynomial mode functions generated by the Gram-Schmidt process are introduced and the numerical results obtained by employing the polynomial mode functions are compared to those obtained by classical beam mode functions. The effect of the time integration procedure on the analysis precision is also investigated. It is found that the two procedures affect the precision of structural analysis significantly.

• Kyungpook Mathematical Journal
• /
• v.48 no.2
• /
• pp.195-206
• /
• 2008

The purpose of this note is to compare the rings of continuous functions, integer-valued or real-valued, in pointfree topology with those in classical topology. To this end, it first characterizes the Boolean frames (= complete Boolean algebras) whose function rings are isomorphic to a classical one and then employs this to exhibit a large class of frames for which the functions rings are not of this kind. An interesting feature of the considerations involved here is the use made of nonmeasurable cardinals. In addition, the integer-valued function rings for Boolean frames are described in terms of internal lattice-ordered ring properties.

• Honam Mathematical Journal
• /
• v.30 no.3
• /
• pp.435-442
• /
• 2008

We introduce the concepts of weakly ${\gamma}$-continuity, strongly ${\gamma}$-closed graph and ${\gamma}-T_2$ spaces. And we study some characterizations and properties or such concepts.

• Communications of the Korean Mathematical Society
• /
• v.24 no.4
• /
• pp.595-603
• /
• 2009

We obtain some characterizations of continuous, open and closed functions in intuitionistic topological spaces. Moreover we reveal that the category of topological spaces is a bireflective full subcategory of the category of intuitionistic topological spaces.

• Journal of Computing Science and Engineering
• /
• v.5 no.4
• /
• pp.294-304
• /
• 2011

Enhancing continuous queries over data streams with temporal functions and predicates enriches the expressive power of those queries. While traditional continuous queries retrieve only the values of attributes, temporal continuous queries retrieve the valid time intervals of those values as well. Correctly evaluating such queries requires the coalescing of adjacent timestamps for value-equivalent tuples prior to evaluating temporal functions and predicates. For many stream applications, the available computing resources may be too limited to produce exact query results. These limitations are commonly addressed through load shedding and produce approximated query results. There have been many load shedding mechanisms proposed so far, but for temporal continuous queries, the presence of coalescing makes theses existing methods unsuitable. In this paper, we propose a new accuracy metric and load shedding algorithm that are suitable for temporal query processing when memory is insufficient. The accuracy metric uses a combination of the Jaccard coefficient to measure the accuracy of attribute values and $\mathcal{PQI}$ interval orders to measure the accuracy of the valid time intervals in the approximate query result. The algorithm employs a greedy strategy combining two objectives reflecting the two accuracy metrics (i.e., value and interval). In the performance study, the proposed greedy algorithm outperforms a conventional random load shedding algorithm by up to an order of magnitude in its achieved accuracy.