• Wind and Structures
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• v.1 no.3
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• pp.255-269
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• 1998

Second-order moments of considerable magnitude arise in tall and slender RC chimneys and towers subject to along-wind loading, on account of eccentricities in the distributed self-weight of the tower in the deflected profile. An accurate solution to this problem of geometric nonlinearity is rendered difficult by the uncertainties in estimating the flexural rigidity of the tower, due to variable cracking of concrete and the 'tension stiffening' effect. This paper presents a rigorous procedure for estimating deflections and second-order moments in wind-loaded RC tubular towers. The procedure is essentially based on a generalised formulation of moment-curvature relationships for RC tubular towers, derived from the experimental and theoretical studies reported by Schlaich et al. 1979 and Menon 1994 respectively. The paper also demonstrates the application of the proposed procedure, and highlights those conditions wherein second-order moments become too significant to be overlooked in design.

• International Journal of Ocean System Engineering
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• v.1 no.3
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• pp.155-164
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• 2011

The second-order motion characteristics of a semi-submersible are investigated in regular waves. A higher-order boundary element method in a frequency domain and a finite element method in a time-domain were applied to the numerical analysis of the nonlinear hydrodynamic force and motion characteristics of semi-submersibles in view point of potential flow. Various aspects of nonlinear effects on the heave and roll of a semi-submersible were numerically investigated and some selected cases were compared with the model test data.

• Korea Trade Review
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• v.46 no.5
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• pp.31-47
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• 2021

Recently, third-party logistics and second-party logistics are well known as a form of logistics service. However, there are several opinions about the effectiveness of second-party logistics and third-party logistics. In this study, the efficiency of second-party logistics companies and third-party logistics companies, which are the main providers of logistics services, was compared and the sales impact on the logistics market was measured. Efficiency was measured using DEA's CCR and BCC models. Debt and equity were used as input variables, and sales, operating profit, and net income were used as output variables. As a result of measuring the efficiency of logistics companies, the efficiency of third-party logistics companies was higher than that of second-party logistics companies in 2019 and 2020, and it had a positive effect on the rate of change in sales.

• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.407-414
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• 2003

The aim of this study was to investigate the effect of third molar extraction on the periodontal status of the adjacent second molar. A total of 61 second molars in 31 adult periodontitis patients were examined. Among them, 27 second molars without adjacent third molars were included in the test group, and 34 second molars with third molar were included in the control group. Clinical parameters including plaque index, gingival index, and pocket depth and radiographic bone loss were measured around the second molar both in test and control group. The result showed that: (1) the mean plaque index and gingival index of control group were higher than these of the test group but the difference was not statistically significant, (2) the mean pocket depth of the control group was higher than the test group significantly at distal and buccal surface, (3) radiographic hone loss was greater in control group than test group significantly, (4) in Pearson correlation analysis between the age of extraction and radiographic bone loss in the test group, a positive relationship was shown(p<0.01). Within limitation of this study, it may be concluded that third molar extraction in periodontitis patients showed an improvement in periodontal status in contrast the patients group having third molar, therefore earlier a removal of third molar may minimize radiographic hone loss of the adjacent second molar.

• Korean Journal of Veterinary Service
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• v.38 no.3
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• pp.155-162
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• 2015

The incidence of second-grade milk production in 9 dairy farms of South Korea was investigated from May 2011 to March 2012, and the serum composition of cows producing first- and second-grade milk in 14 farms including the 9 farms was analyzed. The incidence rate of second-grade milk production of 402 cows in nine dairy farms located in the central and southwestern regions of Korea was 15.4% with the highest rate being 34.4%. Seasonal morbidity was higher during late winter (February) and early summer (June) with the highest rate observed in February (32.6%) followed by November (33.3%). Second-grade milk was most frequently found within one month postpartum (34.1%) while only 3.5% was found during the first 60~90 days of lactating period (n=785, 5 herds). The morbidity increased thereafter (P<0.05) with the highest observed between 270~300 days of lactation (36.1%). The acidity was not significantly different between second-grade ($0.159{\pm}0.026%$) and first-grade milk ($0.158{\pm}0.027%$). Blood serum analysis of 371 cows in the 14 dairy farms indicated that aspartate aminotransferase (AST) level was significantly higher (P<0.001) in cows producing second-grade milk while albumin was significantly lower (P<0.001) than cows producing first-grade milk. Total protein and triglyceride was also significantly low along with glucose, non-esterified fatty acid and blood urea nitrogen in cows producing second-grade milk. Statistical analysis including sensitivity, specificity and positive/negative prediction values showed that lactating cows with high AST, low albumin, total protein and triglyceride levels in the serum tended to produce second-grade milk. It was concluded that serological parameters, especially live functional and metabolic-related serum compositions (AST, albumin, total protein and triglyceride), were significantly influenced in cows producing second-grade milk.

• Journal of Fashion Business
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• v.14 no.3
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• pp.97-115
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• 2010

The purpose of this study is to compare and analyze the relationship among image, customer satisfaction and loyalty of fashion Extension brands. It is expected that this study will provide guidance to fashion companies that are planning to expand their brand in setting up marketing strategies and service strategies. The results of the study are the following. First, women consumers in their 20s had an perception that second brands provided diverse and unique products at cheap prices. However, after purchasing the products, they recognized that the second companies' service level was not so satisfying. Second, consumers were satisfied with the brand awareness, reputation, image, design, color, and packing conditions of the second brands while being not satisfied with the pricing. Third, when the study examined brand loyalty of second brands, consumers have shown high loyalty to the four subsidiary brands. Fourth, the satisfaction level for the four second brands had a significant effect on the brand loyalty for each second brands.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.3
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• pp.359-366
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• 2009

In this paper, we study a tube in a Euclidean 3-space satisfying some equation in terms of the Gaussian curvature, the mean curvature and the second Gaussian curvature.

• Korean Journal of Crystallography
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• v.12 no.2
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• pp.81-87
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• 2001

We have studied the effect of sintering temperature and time on the cation ordering and second phase formation in Ba(Mg/sub 1/3/Nb/sub 2/3/)O₃(BMN) microwave ceramics by using transmission electron microscopy. The relationship between the structural-chemical behavior arid microwave dielectric properties has also been investigated. It is revealed that according to the sintering conditions the BMN ceramics show very diverse local ordering behavior, such as the development of domain twinning and "core-shell"-structured grains and the formation of local disordered domains, though having 1 : 2 cation ordering structure basically. The disordered structure is found in Mg-excess region. Such local chemical variation seems to be caused by the formation of BaNb₂O/sub 6/-like second phase in its neigh-boring grain boundary. The microwave dielectric quality factor of the ceramics decreases greatly with the increase of the structural-chemical inhomogeneity and diversity.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1246-1251
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• 2009

Second Life is a massive multi-user on-line environment; "a 3D virtual world where users can socialize, connect and create using voice and text chat" (http://www.secondlife.com). The paper explores the process and methods to establish a contemporary art exhibition that incudes various shapes and characteristics of art; paintings, 3D sculptures, time-based video arts, technical based arts, and so on. We have also discuss about the technical limitations to make virtual museums in the Second Life and recognitions between human and art works.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1015-1016
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• 2006

The microstructures and properties of pure molybdenum wire and $Mo-La_2O_3$ alloy wire annealed at different temperatures are investigated systematically in this paper. It is shown that the recrystallization temperature, toughness and strength at room temperature of this wire was increased greatly by addition of $La_2O_3$. The room temperature embrittlement of this wire annealed at high temperature is improved remarkably.