• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.401-408
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• 2009

A compression lap splice becomes an important issue due to development of ultra-high strength concrete. Current design codes regarding compression lap splice do not utilize merits of the improved strength of ultra-high strength concrete. Especially, a compression lap splice can be calculated longer than a tension lap splice according to the codes because they do not consider effects of compressive strength of concrete and transverse reinforcement. This anomaly confuses engineers in practice. Design equation is proposed for compression lap splice in 40 to 70 MPa of compressive strength of concrete. The proposed equation is based on 51 specimens conducted by authors. Basic form of the equation includes main parameters which are derived from investigating test results. Through two-variable non-linear regression analysis of measured splice strengths, a strength equation of compression lap splices is then derived. A specified splice strength is defined using a 5% fractile coefficient and a lap length equation is constructed. By the proposed equation, the anomaly of lap lengths in tension and compression is got rid of. In addition, the equation has a reliability equivalent to those of the specified strengths of materials.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.496-502
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• 2017

The purpose of this study is to investigate the applicability of surface-wave techniques for the evaluation of the crack-repairing performance of an epoxy injection method in concrete. In this study, box-shaped concrete specimens with four different crack depths were made with identical mix proportions. The specimens with different crack depths were completely repaired using the same epoxy injection method. The spectral energy transmission ratio of surface waves is used as an index to differentiate the effects of crack depth and crack-repairing performance. The decrease of spectral energy transmission ratio in accordance with the increase of crack depth was identified before repairing. Furthermore, the spectral energy transmission ratio increased after the crack-repairing process in all specimens. The spectral energy transmission ratio is considered as a great indicator for estimating the crack-repairing performance of the epoxy injection method; the ratio was recovered up to almost 95% of the uncracked condition.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.59-73
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• 2011

The purpose of this study is to establish a marketing strategy for the makgeolli manufacturing industry. We fractionized cousumer types depending on motives for purchase of customers who had bought makeolli or drunk it for the last six months. We also examined the relationship between makgeolli selection attributes and customer satisfaction by the cousumer types. SPSS 15.0 statistical package was used to process data. Frequency analysis, factor analysis, a reliability test, K-means cluster analysis, one-way ANOVA, and multiple regression were executed. As a result, the motives to purchase and drink were divided into four factors - marketing, effect on health, self-desires, outside environment; consumers into three types - dependent type, loving type, indifferent type; makgeolli selection attributes into five factors - health characteristics, visual elements, brand characteristics, drinking characteristics, purchase characteristics. It was shown that the makgeolli loving type considered all the makgeolli selection attributes as most important; the dependent type considered the health characteristics and visual elements as less important than the loving type did. The indifferent type considered all the makgeolli selection attributes as less important compared with the other types. Among the makgeolli selection attributes, drinking characteristics and the purchase characteristics had effects on customer satisfaction.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.173-178
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• 2018

The direct metal laser sintering (DMLS) technique would be promising for the full-arch implant-supported restorations due to reduced cost and manufacturing time without potential human errors and casting defects. The aims of this case report were to describe the successful outcome of an implant-supported fixed dental prosthesis in the edentulous maxilla by using the DMLS technology and computer-aided design and computer-aided manufacturing (CAD/CAM) monolithic zirconia crowns, and to describe its clinical implications. A healthy 51-year-old Korean woman visited Seoul National University Dental Hospital and she was in need of a rehabilitation of her entire maxilla due to severe tooth mobility. In this case, all maxillary teeth were extracted and an implant-supported fixed dental prosthesis was fabricated that involved a cobalt-chromium (Co-Cr) framework with the DMLS technique and CAD/CAM monolithic zirconia crowns. Six months after delivery, no distinct mechanical and biological complications were detected and the prosthesis exhibited satisfactory esthetics and function. In this case report, with the DMLS system, the three-dimensional printed prosthesis was created without additional manual tooling and thus, reliable accuracy and passive fit were obtained.

• The Korean Journal of Elementary Counseling
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• v.8 no.1
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• pp.95-107
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• 2009

The purpose of this study was to investigate the effect of social skill training on the class cohesiveness of Elementary School students. The experimental group received 12 times of the social skills training for 6 week period. And each training session which lasted for 40 minutes took place twice a week. A total of 59 5th grade students in randomly selected two classes of D Elementary School in N. Gyongsang participated in this study. They were divided into the two groups, again at random; an experimental group(N=30, Male=18, Female=12) and a control group(N=29, Male=15, Female=14). In this study, the class cohesiveness performance test reorganized into 20 items for the level of elementary students by Shin-suk Gang, was applied, after complemented. And, the collected data were analysed through SPSS 14.0. T-test was applied to find out the difference of the average between the experimental group and the control group and the average difference in the pre-and post-test of the experimental group alone, and to see whether the control group and the experimental group are homogeneous. The research design of this study is pre-and post-test control group design. The result of this study is as follows: The result of Independent t-test and Paried t-test on the cohesiveness score and sub-factor scores tells us that the experimental group which received the social skills training showed better achievement that deserves our attention compared to the control group. This result suggests that student's class cohesiveness(class atmosphere, mutual trust, morale, a sense of unity, communication) is positively affected by the social skill training. Accordingly, social skill training which develops class cohesiveness can be an effective strategy for elementary school students to make them more intimate and cooperative with their classmates.

• Journal of Broadcast Engineering
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• v.19 no.3
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• pp.329-341
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• 2014

Kernel-based mean-shift object tracking has gained more interests nowadays, with the aid of its feasibility of reliable real-time implementation of object tracking. This algorithm calculates the best mean-shift vector based on the color histogram similarity between target model and target candidate models, where the color histograms are usually produced after uniform color-space quantization for the implementation of real-time tracker. However, when the image of target model has a reduced contrast, such uniform quantization produces the histogram model having large values only for a few histogram bins, resulting in a reduced accuracy of similarity comparison. To solve this problem, a non-uniform quantization algorithm has been proposed, but it is hard to apply to real-time tracking applications due to its high complexity. Therefore, this paper proposes a fast non-uniform color-space quantization method using the histogram equalization, providing an adjusted histogram distribution such that the bins of target model histogram have as many meaningful values as possible. Using the proposed method, the number of bins involved in similarity comparison has been increased, resulting in an enhanced accuracy of the proposed mean-shift tracker. Simulations with various test videos demonstrate the proposed algorithm provides similar or better tracking results to the previous non-uniform quantization scheme with significantly reduced computation complexity.

• Journal of Internet Computing and Services
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• v.19 no.5
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• pp.1-11
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• 2018

The Blockchain is a technique that prevents data from being manipulated and guarantees the integrity and reliability of the data by all participants in the network jointly owning and validating the data. Since the Blockchain characterized by security, scalability and transparency, it is used in a variety of fields including logistics, distribution, IoT and healthcare, including remittance. In particular, there is a growing interest in smart contract that can create different forms of contracts and automate implementation based on Blockchain. Smart Contract can be used to pre-programme contracts and are implemented immediately when conditions are met. As a result, digital data can be more reliable. In this paper, we are conducting a study on the smart contract design as a way to solve such problems as illegal misuse of funds on virtual currency, which has become an issue recently. Through this process, we applied the customer identification and money laundering prevention process using smart contract, and then check the possibility of preventing money laundering and propose the ASM (AML SmartContract Mechant) design.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.3
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• pp.22-30
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• 2010

This paper proposes a combination system of Adaptive Modulation and Coding (AMC) and Multiple Input Multiple Output (MIMO), which improves the throughput and has a better reliability. In addition, the system includes Precoding, Antenna Subset Selection and MIMO Mode Selection scheme. Finally, we make a performance analysis of the proposed system. The principal environmental parameters for the simulation experiment consist of a frequency non-selective rayleigh fading channel and a Spreading Factor (SF) of 16. Other parameters may be included in order to fulfill the requirements of the HSDP A Standard. The proposed system has a higher throughput and more reliability than the conventional system, which does not include MIMO Mode Selection scheme, Precoding or Antenna Subset Selection. According to the simulation results, the proposed system reaches the maximum throughput at 8dB, presentlng an improvement of 6dB and twice higher throughput, respect to the conventional system. Specifically, at the point of -6dB, the conventional system reaches 2.5Mbps, while the proposed system reaches 6.4Mbps at the same SNR. Also, at the point of 2dB, each system reaches 7.5Mbps (conventional system) and 15.3Mbps (proposed system), with near twice the difference. According to the results exposed above, we can conclude that the system proposed in this paper has, as the greatest contribution, the improvement of the throughput, especially, the average throughput.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.2
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• pp.46-54
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• 2012

We propose a continuously varying contact pressure(CVCP)-adaptive feature extraction algorithm for pulse diagnostic analysis. The CVCP method measures the pulse waveform with continuously increasing contact pressure(CP). This method offer a high resolution signal of the pulse waveform amplitude(PWA) as a function of the contact pressure. Therefore it enables us to overcome the limitation of commercially available pulse-taking devices whose analysis rely on a few number of PWA-CP pairs. We show that an efficient feature extraction algorithm which covers the features of the CVCP-method can be developed by sequentially applying Fast Fourier Transform, peak detection by center-to-edges method, baseline drift removal, detection of the percussion wave upstroke by intersecting tangent method and detection of the analysis region. Finally, by a clinical study with 30 subjects, we show that our CVCP-adaptive feature extraction algorithm detected the upstroke with accuracy of 99.46% and sensitivity of 99.51%, which were about 4.82% and 2.46% increases respectively, compared to a conventional feature extraction method. The proposed CVCP method and the CVCP-adaptive feature extraction algorithm are expected to improve the accuracy in the pulse diagnostic algorithms such as floating/sunken pulse qualities and deficient/excess pulse qualities.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.12 no.1
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• pp.53-62
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• 2018

In this study, we developed a smart 1RM system for national health management and physical fitness, which enables quantitative 1RM measurement in various types of exercise using digital pulley technology, and to test the effect on training by using it. We developed the smart 1RM system, which is composed of portable muscle strength measuring device, Bluetooth communication based mobile phone data transmission and circuit diagram, and height adjustable system body. We recruited the 30 participants with 20th aged and divided into training and non-performing groups with 15 participants randomly. The participants performed 5 sets of elbow, lumbar, knee extension / flexion 10 times using smart 1RM system and the experimental period was 3 days a week for a total of 8 weeks. The experimental results showed that the maximum strength of the elbow, lumbar, and knee joints was significantly improved before and after maximal muscle strength training in the training group. Oxygen intakes during 1RM exercise mode showed 10.91% than endurance. To verify the validity of the smart 1RM maximal strength data, the reliability was 0.895 (* p <0.00). This study can be applied to the early rehabilitation treatment of the elderly and rehabilitation patients more quantitatively using the national health care.