• Geomechanics and Engineering
• /
• v.33 no.6
• /
• pp.611-624
• /
• 2023

Soil properties make it attractive as a building material due to its mechanical strength, aesthetically appearance, plasticity, and low cost. However, it is frequently necessary to improve and stabilize the soil mechanical properties with binders. Soil-cement is applied for purposes ranging from housing to dams, roads and foundations. Unconfined compression strength (UCS) and split tensile strength (CD) are essential mechanical parameters for ascertaining the aptitude of soil-cement for a given application. However, quantifying these parameters requires specimen preparation, testing, and several weeks. Methodologies that allowed accurate estimation of mechanical parameters in shorter time would represent an important advance in order to ensure shorter deliverable timeline and reduce the amount of laboratory work. In this work, an extensive campaign of UCS and CD tests was carried out in a sandy soil from the Leiria region (Portugal). Then, using the machine learning tool Neural Pattern Recognition of the MATLAB software, a prediction of these two parameters based on six input parameters was made. The results, especially those obtained with resource to a Bayesian regularization-backpropagation algorithm, are frankly positive, with a forecast success percentage over 90% and very low root mean square error (RMSE).

• ETRI Journal
• /
• v.46 no.2
• /
• pp.184-193
• /
• 2024

This paper presents the performance evaluation of an amplify-and-forward (AF) relay-assisted multiuser multiple input-multiple output (MU-MIMO) downlink transmission system for correlated fading channels. The overall system performance was improved by incorporating a double-quadrature spatial modulation (DQSM) scheme. The bit error rate (BER) performance and detection complexity of the AF-MU-MIMO-DQSM system were analyzed and compared with those of a conventional AF-MU-MIMO system under the same conditions and parameters. The results showed that the correlated fading channel severely affected the performance of systems with higher spectral efficiency (SE). Considering an SE of 12 bpcu/user, the AF-MU-MIMO-DQSM system yielded a gain of up to 3 dB in BER performance compared with that of its conventional counterpart for the analyzed cases. In terms of detection complexity, the AF-MU-MIMO-DQSM system showed a reduction of up to 56 % compared with that of the conventional system for the optimal maximum likelihood detection criterion.

• Communications for Statistical Applications and Methods
• /
• v.13 no.3
• /
• pp.587-605
• /
• 2006

Recent results in applied statistics have shown that the presence of periodicities in time series may influence the estimation and testing of the fractional differencing parameter. In this article, we provide further evidence on the issue by using several procedures of fractional integration. The results show that in the presence of periodicities, the order of integration can be erroneously detected. An empirical application in the context of seasonal data is also carried out at the end of the article.

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.93.5-93
• /
• 2002

Distributed Artificial Intelligence (DAI) aims to study and develop techniques that allow interaction among intelligent entities. In the last two decades, some types of DAI architecture have been proposed for various fields. However, it can be noticed that the inconsistency phenomenon has not been dealt with properly. This is probably due to the fact that this phenomenon cannot be handled (at least directly) with classical logic. Hence, to deal with such inconsistencies directly, one should employ a logic other than the classical one. The DAI Architecture described in this work is based on a nonclassical logic called Annotated Paraconsistent Logic.

• Korean Journal of Crystallography
• /
• v.12 no.4
• /
• pp.227-232
• /
• 2001

Structure-physical properties relationships for Aurivillius ceramics are discussed, with empha-sis in symmetry considerations. Single-crystal materials and polycrystal ceramics are analysed. Electric and magnetic coupling properties are considered. Colour Symmetry Groups and Texture Analysis tool are emploed. Symmetry conditions for polarisation vectors and inverse pole figures related to Aurivillius phases are given. The influence of crystallographic texture of the physical properties of polycrystalline Aurivillius ceramics is evaluated.

• Journal of the Korean Mathematical Society
• /
• v.44 no.3
• /
• pp.647-659
• /
• 2007

Relationships between the Ricci curvature and the squared mean curvature and between the shape operator associated with the mean curvature vector and the sectional curvature function for slant submanifolds of an S-space-form are proved, particularizing them to invariant and anti-invariant submanifolds tangent to the structure vector fields.

• The Bulletin of The Korean Astronomical Society
• /
• v.39 no.1
• /
• pp.42.2-42.2
• /
• 2014

We present high-resolution optical spectra of newly selected candidates of intermediate-mass black holes. The sample was selected based on the variability and spectral shape in X-ray. The spectra was taken with Magellan 6.5 m Clay Telescope and cover the rest-frame region 3500-10000A. The high spectral resolution (R~4000) of the spectrum allows us to estimate BH masses of the sources. Interestingly, the majority of the sample appears to have broad emission lines. Using this dataset, we will estimate the BH masses and Eddington ratio in order to understand their physical properties.

• Korean Architects
• /
• no.9 s.47
• /
• pp.20-25
• /
• 1972

-편집주- ㆍ이사진들(ARCHITECTURE WITHOUT ARCHITECTS)은 1964년 11월 9일부터 1965년 2월 7일까지 약 4개월간에 걸쳐서 미국의 현대미술관에서 전시된 작품들로서 이 전시회는 현대미술관의 국제부의 협찬하에서 건축가 B. Rudofsky가 연구, 제작, 편집, 전시 및 디자인까지 도맡아 완성한 것이며, ㆍ이 비형식적이라 할 수 있는 건축물의 전시를 함에 있어서는 죤ㆍ시몬ㆍ구겐하임재단과 포드재단의 재정적인 지원을 받아서 이 계획의 연구를 이룰 수 있었으며 또한 건축가 Walter Gropius, Pietro Belluschi, Jose' Luis Sert, Richard Neutra, Gio Ponti, Kenzo Tange 등의 열광적인 협조와 추천으로서 이들 작품의 전시가 가능했다고 한다. ㆍ본 자료를 제공해주신 조창한 선생님에게 감사를 드립니다.

• Korean System Dynamics Review
• /
• v.6 no.2
• /
• pp.37-52
• /
• 2005

Conflict resolution in decision-making groups is studied using a System Dynamics model. The model is developed using a grounded-theory approach. Some preliminary results are shown. The results seem to be in line with much empirical research done in the management literature about conflict and conflict resolution at the group level of analysis. Ideas for further research are discussed.

• Journal of Veterinary Science
• /
• v.19 no.6
• /
• pp.862-864
• /
• 2018

An elective laparoscopic ovariectomy on a healthy dog revealed a cystic structure in the left ovary. The surgical procedure was successful. Histopathological examination showed the presence of a teratoma adjacent to the ovary. To the best of the authors' knowledge, this is the first reported case of an ovarian teratoma removed by laparoscopic ovariectomy in a dog by using a multiport laparoscopic ovariectomy technique.