• Journal of Magnetics
• /
• v.22 no.2
• /
• pp.238-243
• /
• 2017

In this research, we report the preliminary results of an insertional type parallel transmission (pTx) array that has 7-elements that are placed in the space above a patient table as a transmit (Tx) coil to give an RF transmission ($B_1{^+}$) field for the body object of a 3 Tesla (T) MRI system. In previous research, we have tried to compare the performances of different coil elements and array geometries for a pTx body image. Based on these results, we attempt to obtain a human image with the proposed pTx array. Through the simulation and experimental results, we introduce a possible structure of multi-channel Tx array and verify the utility of a multi-channel Tx body image using $B_1{^+}$ shimming. The insertional pTx array, combined with a receiver (Rx) array coil, provides an enhanced $B_1{^+}$ field homogeneity in a large ROI image as a result of $B_1{^+}$ shimming applied over the full body size object. Through this research, we hope to determine the usefulness of the proposed insertional type RF coil combination for 3 T body imaging.

• Journal of Korea Multimedia Society
• /
• v.22 no.2
• /
• pp.194-202
• /
• 2019

In the information society represented by the Fourth Industrial Revolution, various types of data and information that are difficult to see are produced, processed, and processed and circulated to enhance the value of existing goods. The IoT(Internet of Things) paradigm will change the appearance of individual life, industry, disaster, safety and public service fields. In order to implement the IoT paradigm, several elements of technology are required. It is necessary that these various elements are efficiently connected to constitute one system as a whole. It is also necessary to collect, provide, transmit, store and analyze IoT data for implementation of IoT platform. We designed and implemented a big data processing IoT platform for IoT service implementation. Proposed platform system is consist of IoT sensing/control device, IoT message protocol, unstructured data server and big data analysis components. For platform testing, fixed IoT devices were implemented as solar power generation modules and mobile IoT devices as modules for table tennis stroke data measurement. The transmission part uses the HTTP and the CoAP, which are based on the Internet. The data server is composed of Hadoop and the big data is analyzed using R. Through the emprical test using fixed and mobile IoT devices we confirmed that proposed IoT platform system normally process and operate big data.

• Coupled systems mechanics
• /
• v.10 no.1
• /
• pp.1-19
• /
• 2021

Composite nature of the masonry structures in general causes complex and non-linear behaviour, especially in intense vibration conditions. The presence of different types and forms of structural elements and different materials is a major problem for the analysis of these type of structures. For this reason, the analysis of the behaviour of masonry structures requires a combination of experimental tests and non-linear mathematical modelling. The famous UNESCO Heritage Old Bridge in Mostar was selected as an example for the analysis of the global behaviour of reinforced stone arch masonry bridges. As part of the experimental research, a model of the Old Bridge was constructed in a scale of 1:9 and tested on a shaking table platform for different levels of seismic excitation. Non-linear mathematical modelling was performed using a combined finite-discrete element method (FDEM), including the effect of connection elements. The paper presents the horizontal displacement of the top of the arch and the failure mechanism of the Old Bridge model for the experimental and the numerical phase, as well as the comparison of the results. This research provided a clearer insight into the global behaviour of stone arch masonry structures reinforced with steel clamps and steel dowels, which is significant for the structures classified as world cultural heritage.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.15 no.1
• /
• pp.12-18
• /
• 1978

From the state table of sequential machines, Roomers) obtained minimal k co-mapping chain(k-CC) and proposed an algorithm obtaining binary partitions which were seed partitions of S-shift registers. By comparing and processing bits simply, this paper obtained two different algorithms more efficient than that of Roome's for obtaining such binary partitions and defined the concept of the triple pair of the basis partitions. By using the concept, given set of basis partitions was reduced to the set containing elements of the triple pair only and the algorithm became quite simple.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.15 no.6
• /
• pp.66-78
• /
• 1978

An assembly package program is developed for a computerize4 operation of a drilling machine system utilizing a microprocessor. Different drilling instruction requires merely the input of different sets of input data. To make pulse motors to follow their input pulse trains with fidelity, an optimum start-stop rate matrix is proposed, whose elements are determined according to the pulse motor torque and the load inertia of the mechanical system composed of a workpiece and a worktable.

• Earthquakes and Structures
• /
• v.11 no.2
• /
• pp.281-295
• /
• 2016

This paper presents a study on a non-seismically designed reinforced concrete (RC) frame structure. The structure was a existing three-story office building constructed according to the 1990s practice in Vietnam. The 1/3 scaled down versions of structure was tested on a shake table to investigate the seismic performance of this type of construction. It was found that the inter-story drift and the overall behavior of structure meet the requirements of the actual seismic design codes. Then, nonlinear time history analyses are carried out using the fiber beam- column elements. The comparison between the experimental and simulation results shows the performance of the time history analysis models.

• 전기의세계
• /
• v.18 no.3
• /
• pp.15-23
• /
• 1969

A combinational circuit is one of the fundamental elements in digital circuits, containing electronic computers. W.A. Davis presented a new approach to the problem of assigning binary input codes so that the combinational circuits necessary to realize the given output functions may be minimized. This paper has derived an algorithm for determining the actual cost of a given assignment scheme in Davis method. First, the combinations of partitions realizing the output functions are obtained and then those among them implementing all of the output functions are found by using a table. In consequence it has been proved that by this algorithm the process of the assignment in a schcme with 16 states and 3 determined partitions can be reduced to 1/10$^{6}$ .

• Journal of the Korean housing association
• /
• v.10 no.1
• /
• pp.63-73
• /
• 1999

The purpose of this study is to provide new design techniques for designers to design energy saving balcony in the apartment house using solar energy passively. These design techniques are examined with some samples of foreign buildings used solar energy passively. To classify these design techniques, this study sorts out the energy saving design elements from the preliminary studies. The results of this study show how to apply each design technique to the design of balcony in the apartment house and present a classification table of these techniques. Finally, this study suggests a design solution which can be applied in the design of balcony in existing apartment house.

• Journal of the Korean Society for information Management
• /
• v.24 no.3
• /
• pp.83-92
• /
• 2007

Semantic libraries can be used for EDI messages to exchange by implementing the semantic dictionaries. This paper describes the design information of semantic libraries for the field engineers to implement the semantic dictionary using metadata. The components of semantic libraries are semantic elements, semantic units and mapping tables. The basic characteristics and design methods related implementing are proposed. Also the metadata semantic dictionaries including the components and rules are introduced.

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.1195-1198
• /
• 1987

This paper develops algorithms of element generation, addition, multiplication and inversion based on GF($2^m$). Since these algorithms are implemented by general purpose computer, these are more efficient than the conventional algorithms(Table Lookup, Euclid's Algorithm) in each operation. It is also implied that they can be applied to not only the normally defined elements but the arbitrarily defined ones for constructing multi-valued logic function.