• Explosives and Blasting
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• v.8 no.3
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• pp.3-13
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• 1990

First ot of all, under given condition such as bit gage of 36mm Drill bit with right class of jack-leg-experimental test carried out from two face of Bench, firing of each hole brought 90 degree Angle face and them measured length of Burden and charged ammount of powder as following. $ca=\frac{A}{SW}$ A=Activated Area A=nd i=m S=Peripheral length of charged, room Ca=Rock Coeffiecency d: di=Hole diameter When constructed subway of Seoul in 1980 the blasting works increased complaint of ground vibration, in order to prevent the damage to structures. Some empirical equations were made as follows on condition with Jackleg Drill (Bit Gage 36mm) and within 30 meter distance between blasting site and structures. $V=K(D/W)^{-n}$ N=1.60 - 1.78 K= 48 - 138 Project is one of contineous works to above a determination of empirical equation on the cautious blasting vibration with Crawler Drill (70-75mm) in long distance. $V=41(D/\sqrt[3]{W})^{-1.41}$ $30m\le{D}\le{100m}$ $V=124(D/\sqrt[3]{W})^{-1.66}$ $100m\le{D}\le{285m}$.

• Journal of the Korean Applied Science and Technology
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• v.20 no.2
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• pp.154-164
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• 2003

This paper has applied a simple model to the mass transfer mechanism of Cr(VI) with crownether in a batch-type, supported liquid membrane module. Concentration at pH 3 are as follows : 0.012 kmol/$m^3{\le}$18-crown-6${\le}$0.036 kmol/$m^3$ and 20 g/$m^3{\le}$ Cr(VI)${\le}$500 g/$m^3$. The measured values of forward- and backward-reaction rate constants between Cr(VI) and 18-crown-6 were used to simulate the model with the mass conservation equation and associated boundary conditions. Comparison between the experimental and simulated facilitated factor of Cr(VI) transport led to classification of reaction regions.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.1
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• pp.120-124
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• 1996

The postoperative maxillary cyst develops as a delayed complication after surgical intervention or Caldwell-Luc operation in the maxillary sinus and was also reported that it could occur after Le Fort I osteotomy. This is also called as surgical cliated cyst because of its lining epithelium is usually lined by a pseudo-stratfied ciliated columnar epithelium. This report represents a case of postoperative maxillary cyst which developed within the anterior of maxilla and in association with nasal mucosa 6 years after a Le Fort I osteotomy. In 1989, 26-year-old male complained of his mandibular prognathism and underwent orthogmathic surgery, Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, partial glossectomy.

• Journal of the Korean Mathematical Society
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• v.43 no.3
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• pp.529-538
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• 2006

In this paper we derive the central limit theorem for ${\sum}^n_{i=l}\;a_{ni}{\xi}_{i},\;where\;\{a_{ni},\;1\;{\le}\;i\;{\le}n\}$ is a triangular array of non-negative numbers such that $sup_n{\sum}^n_{i=l}\;a^2_{ni}\;<\;{\infty},\;max_{1{\le}i{\le}n\;a_{ni}{\to}\;0\;as\;n{\to}{\infty}\;and\;{\xi}'_{i}s$ are a linearly positive quadrant dependent sequence. We also apply this result to consider a central limit theorem for a partial sum of a generalized linear process of the form $X_n\;=\;{\sum}^{\infty}_{j=-{\infty}}a_{k+j}{\xi}_{j}$.

• Journal of the Optical Society of Korea
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• v.17 no.1
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• pp.22-26
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• 2013

The author analyzes the luminous efficiency of the phosphor-conversion white light-emitting diode (LED) that consists of a blue LED chip and a yellow phosphor. A theoretical model is derived to find the relation between luminous efficiency (LE) of a white LED, wall-plug efficiency (WPE) of a blue LED chip, and the phosphor absorption ratio of blue light. The presented model enables to obtain the theoretical limit of LE and the lower bound of WPE. When the efficiency model is applied to the measured results of a phosphor-conversion white LED, the limit theoretical value of LE is obtained to be 261 lm/W. In addition, for LE of 88 lm/W at 350 mA, the lower bound of WPE in the blue LED chip is found to be ~34%. The phosphor absorption ratio of blue light was found to have an important role in optimizing the luminous efficiency and colorimetric properties of phosphor-conversion white LEDs.

• 중국학논총
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• no.71
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• pp.23-40
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• 2021

'过' and '了' are the key points, as well as difficult ones, in the academic study of Chinese grammar and language teaching. This article analyzes this language use by taking two sentence structures as example, namely 'Pao le.' and 'Pao guo le.'. As the semantic meanings of 'V+了2' and 'V+过1+了2' are very similar. Therefore, it can be confusing for non-native speakers to master this usage. This article attempts to sort out and analyze the usage environment and pragmatic characteristics of 'V+过1+了2' by employing the examples from the data of Corpus of the Chinese Linguistics Research Center of Peking University. By focusing on the usage environment and pragmatic characteristics of '过' and it is desirable for teachers to combine semantics, syntax and pragmatics while explaining the grammar point, in order for learners to understand accurate information quickly and learn how to use it.

• Communications of the Korean Mathematical Society
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• v.38 no.1
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• pp.1-9
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• 2023

An le-module M over a commutative ring R is a complete lattice ordered additive monoid (M, ⩽, +) having the greatest element e together with a module like action of R. This article characterizes the le-modules _RM such that the pseudo-prime spectrum X_M endowed with the Zariski topology is a Noetherian topological space. If the ring R is Noetherian and the pseudo-prime radical of every submodule elements of _RM coincides with its Zariski radical, then X_M is a Noetherian topological space. Also we prove that if R is Noetherian and for every submodule element n of M there is an ideal I of R such that V (n) = V (Ie), then the topological space X_M is spectral.

• International Journal of High-Rise Buildings
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• v.13 no.2
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• pp.187-194
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• 2024

The 53-meter tall Albizzia Tower is a white, mineral building with a mixed concrete and wood structure. It harmoniously interacts with the high rises of La Confluence. Its base is largely open, in direct relation to the public space. The spaces are mutable, reversible, moldable thanks to a streamlined structure: posts, beams in glued laminated wood, with posts pushed back on the facade to facilitate the layout of office and housing floors, CLT floors with a span of 7 meters.

• Journal of architectural history
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• v.7 no.3 s.16
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• pp.151-170
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• 1998

This study is about Le Corbusier's early years of loarning and training at La Chaux-de-Fonds. It is an attempt to show how Le Corbusier's groundwork was laid which characterize his work throughout the life. Charles Edouard Jeanneret was trained as a watch engraver and wished to be a painter. C. L'Eplattenier was to play a decisive role in shaping the young introspective boy's future. He encouraged Jeanneret's habit of the close study and observation of nature. Jeanneret was not the product of an established school, but instead made the unusual choice of educating himself. He found two indispensible sources of inspiration in study the past and in contemplating nature. His four years of self-education consisted of extensive reading, summer travels and winter layovers in larger cities-Vienna, Paris, Berlin-while sketching in museums or apprenticing local architects-Pellet, Behrens-. All these impressions then blended together to become part of a comprehensive source book of knowledge and imagination of the later Le Corbusier. A largely self-taught man, he never stopped making notes, drawing and writing, always aspiring to a clearer understanding of the meaning and underlying principles of objects and architecture. Jeanneret's five villas in La Chaux-de-Fonds are barometers which show the sequences of his development and change as an architect. In 1917, being thirty, he uprooted himself from his hometown to get a wider range of opportunities and moved to Paris. By that time Jeanneret was almost ready to blossom into Le Corbusier It was during this formative years of his life that Le Corbusier established the working method, mind-set and philosophical basis that determined the course of an architect in the making.

• The Journal of Advanced Prosthodontics
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• v.10 no.1
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• pp.73-78
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• 2018

PURPOSE. The purpose of this study was to analyze the effects of two different implant surface treatments on initial bone connection by comparing the Removal Torque Values (RTQs) at 7 and 10 days after chemically modified, sandblasted, large-grit and acid-etched (modSLA), and Laser-etched (LE) Ti implant placements. MATERIALS AND METHODS. Twenty modSLA and 20 LE implants were installed on the left and right tibias of 20 adult rabbits. RTQs were measured after 7 and 10 days in 10 rabbits each. Scanning electron microscope (SEM) photographs of the two implants were observed by using Quanta FEG 650 from the FEI company (Hillsboro, OR, USA). Analyses of surface elements and components were conducted using energy dispersive spectroscopy (EDS, Horiba, Kyoto, Japan). RESULTS. The mean RTQs were $12.29{\pm}0.830$ and $12.19{\pm}0.713$ Ncm after 7 days (P=.928) and $16.47{\pm}1.324$ and $16.17{\pm}1.165$ Ncm after 10 days (P=.867) for LE and modSLA, respectively, indicating no significant inter-group differences. Pore sizes in the LE were $40{\mu}m$ and consisted of numerous small pores, whereas pore sizes in the modSLA were $5{\mu}m$. In the EDS analysis, Ti, O, and C were the only three elements found in the LE surfaces. Na, Ca, Cl, and K were also observed in modSLA, in addition to Ti, O, and C. CONCLUSION. The implants showed no significant difference in biomechanical bond strength to bone in early-stage osseointegration. LE implant can be considered an excellent surface treatment method in addition to the modSLA implant and can be applied to the early loading of the prosthesis clinically.