• Journal of Korean Society of Steel Construction
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• v.29 no.6
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• pp.443-453
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• 2017

In this study, a trapezoidal hollow ball is used, instead of a spherical hollow ball commonly used in void slab, to secure the high hollow ratio in the deck type void slab. The bending and shear performance was measured with consideration for the shape change of the hollow ball. And to confirm the effect of deck plate and truss wire on shear performance, experiments were performed depending on the installation directions of the one-way deck plate. As a result, the bending performance of the deck type void slab with a trapezoidal hollow ball was similar to that of the void slab with a spherical hollow ball. However, according to the data of shear strength examined, the contribution of shear performance enhancement of the truss wire had a more effect on the shear performance of deck type void slab, rather than the influence by changing of the shape of hollow ball. In the previous studies, the shear strength is reduced to about 60%, due to the reduction of the effective section of concrete by installation of hollow ball. But in this experiment, the maximum load of specimen, in which the deck was installed in horizontal direction, so expected to have no influence on the shear performance, was only reduced to about 87%, due to the truss framework of truss wire.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.242-251
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• 2010

In comparison with other terrestrial ecosystems, rice paddies are unique because they provide the primary food source for over 50% of the world's population, and act as major sources of global methane. The present paper summerizes a long-term field study that combine carbon isotopes, and canopy-scale flux measurements in an irrigated rice paddy, in conjugation with continuous monitoring of environmental, and vegetational factors. Both $CO_2$, and methane fluxes were largely influenced by soil temperature, and moisture conditions, especially across drainage events. Soil-entrapped $CO_2$, and methane showed a gradually increasing trend throughout growing season, but rapidly decreased upon flood water drainage. These variations in flux were well correlated with changes in concentration, and isotope ratio of soil $CO_2$, and methane, and of atmospheric $CO_2$, and methane within, and above the canopy. The isotopic signature of the gas exchange process varied markedly in response to change in contribution of soil respiration, belowground storage, fraction of $CO_2$ recycled, magnitude, and direction of $CO_2$ exchange, transport mechanism, and fraction of methane oxidized. Our results clearly demonstrate that stable isotope analysis can be a useful tool to study underlying mechanisms of gas exchange processes under natural conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.4
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• pp.259-274
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• 2017

To get some informations for sustainable paddy use, the productivities of soils with two years of cropping systems were estimated through pot experiment using two pretreated groups of not autoclaved 'natural'- and 'autoclaved'-soils without any fertilization. And then the relationship between the productivities, called yield potentials, and the characteristics of soils as affected by cropping systems, such as rice-rice (R-R), ricebarley-rice-barley (R-B-R-B), rice-barley-rice-wheat (R-B-R-W), soybean-barley-soybean-barley (S-B-S-B), of which barley and wheat were composted at a level of $10MT\;ha^{-1}$, and S-B-S-B without compost, was analyzed. These treatments were established in mid-mountainous loam paddy, which contained exchangeable Ca of $11.8cmol_c\;kg^{-1}$, located at the altitude of 285 m above sea level in Sangju of Korea. Crops for the estimation of soil productivity were rice cv. 'Seolemi' and soybean cv. 'Chamol'. As a result, under the natural soils condition, rice grain and straw were highly produced in composted S-B-S-B soils (p < 0.05) and lowly in R-R soils (p < 0.05). While soybean grain and stem were higher in R-R soils (p < 0.05) than other soils which not significantly different each other. In case of autoclaved soils, the yield potentials of rice and soybean were high together in either composted R-B-R-B/W or S-B-S-B soils compared to R-R and uncomposted S-B-S-B soils (p < 0.05). In especial, these yield potentials under the natural soils condition were commonly influenced by soil porosity showing negative correlation for rice (p < 0.01); positive for soybean (p < 0.05). And the porosity possibly reversed even the symbiotic contribution of indigenous Bradyrhizobium japonicum for soybean. Under autoclaved soils condition the potentials of rice and soybean showed negative correlations with soil C:N ratio (p < 0.05) similarly to the case of rice in the natural soils.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.171-176
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• 2008

The comparative molecular similarity indices analysis (CoMSIA) models between 3${\beta}$-Hydroxy-12-oleanen-28-oic acid (1-30) analogues as substrate molecule and their inhibitory activities ($pI_{50}$) against protein tyrosine phosphatase (PTP)-1B were derived and discussed quantitatively. Listing in order, the CoMFA>CoMSIA${\geq}$HQSAR>2D-QSAR model, these QSAR models had the better statistical values. The optimized CoMSIA F1 model at grid 3.0${\AA}$ had the best predictability and fitness ($q^2$=0.754 and $r^2$=0.976) by field fit alignment. The order of contribution ratio (%) of CoMSIA fields concerning the inhibitory activities was a H-bond acceptor (48.9%), steric field (25.8%) and hydrophobic field (25.4%), respectively. Therefore, the inhibitory activities of substrate molecules against PTP-1B were dependent upon H-bond acceptor field (A) of $R_4$-group. From the analytical results of CoMSIA contour maps, oleanolic acid derivatives will have better inhibition activities if $R_1$ group has H-bond acceptor disfavor, $R_3$group has steric disfavor and $R_4$ group has steric, hydrophobic, H-bond favor.

• Journal of Korea Technology Innovation Society
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• v.12 no.2
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• pp.291-311
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• 2009

Intellectual Property(IP) investment and its management are an key driver to create corporate value and intangible asset value through corporate's competitiveness. The purposes of this study are to survey capability of IP management and assess the effects of IP investment and its management on the separation into groups of intangible asset value. In order to attain those purposes of this study, sample companies were taken and categorized into three groups by the level of intangible asset value ratio, and data for IP investment such as R&D expenditure and advertising expenditure were collected from 90 manufacturing companies, and data for IP management capability about patent, design and brand were taken through survey. The final results showed as followed: First, IP management capability were generally not sufficient in the results of survey. Second, mean vector for the four variables were significantly different among three groups in multivariate analysis variance. Third, the order of their contribution to separating the groups were R&D expenditure, advertising expenditure, patent management, management of design and brand in canonical variate analysis. Fourth, R&D and patent management capability were significantly related to the separation of three groups, while advertising expenditure were not significant and management of design and brand were not sure of Significance in multinomial logit discriminant analysis. Fifth, exploratory power of the discriminant model were estimated by 53% in classification analysis. Finally, strategic policy for IP investment and its management should be taken urgently to create intangible asset value and to improve the capability of its management.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.5
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• pp.480-496
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• 2017

CMAQ (Community Multiscale Air Quality)-HDDM (High-order Direct Decoupled Method) simulations with MICS-Asia 2010 and INTEX-B 2006 emissions inventories were performed to investigate the impact of Chinese $NO_x$ and VOC emissions on 1-hr ozone concentrations over South Korea during May to July in 2014. Chinese $NO_x$ and VOC emissions in MICS-Asia 2010 were 60% higher and 100% lower than those in INTEX-B 2006 during the simulation period. It makes the ratio of Chinese VOC to $NO_x$ emissions in INTEX-B 2006 (Case 1) is 3.2 times higher than that in MICS-Asia 2010 (Case 2). When the observed period mean 1-hr ozone concentration averaged across 106 air monitoring sites in the SMA (Seoul Metropolitan Area) was 37.6 ppb, the modeled values were similar to each other; 37.3 ppb for Case 1, and 40.4 ppb for Case 2. Both cases show that daily maximum 1-hr ZOC (Zero-Out Contribution) of Chinese $NO_x$ and VOC emissions were as high as 55 ppb and 35 ppb for the episode respectively. Correlation coefficients between ZOC of Chinese $NO_x$ and VOC emissions and the SMA daily maximum 1-hr ozone were 0.49~0.69. It indicates that Chinese emissions occasionally affect the SMA daily ozone peaks. On the other hand, Case 2 predicted 7 ppb and 1 ppb higher ZOC of Chinese $NO_x$ and VOC emissions than Case 1, when simulated ozone in the SMA is over 80 ppb. It implies that upwind $NO_x$ emissions would be more important than upwind VOC emissions for the long-range transport of ozone in Northeast Asia.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.170-177
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• 2020

The Korean government's R&D budget has risen steadily annually, reaching 24.2 trillion won in 2020, and the ratio of R&D expenditure to GDP ranked high among OECD countries. However, national science and technology innovation ranked low among OECD countries. This study focused on Korean government-funded research institutes in the field of science and technology by analyzing the effects of budget and workforce input on research performance in order to provide directions for management. Multiple regression analysis was conducted with budget and workforce input as independent variables, which influence major research outcomes (SCI paper, patent, royalty). In the research budget, only government contribution had a positive effect on SCI thesis performance, and the increase in the government project and private project funding had a negative effect on the number of patents and technology royalties. For the workforce, the positive effect of regular workers on all research achievements was 3-6 times more than that of non-regular workers. Through this study, policy implications such as establishment of institutional performance indicators according to research types were derived for the outcome driven management of government-funded research institutes in the field of science and technology.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4597-4601
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• 2015

Background: Macrophage migration inhibitory factor (MIF) -173G/C (rs755622) gene polymorphism has been associated with cancer risk. Previous studies have revealed that MIF -173G/C gene polymorphism may increase cancer in the Chinese population, while results of individual published studies remain inconsistent and inconclusive.We performed this meta-analysis to derive a more precise estimation of the relationship. Materials and Methods: We conducted a search on PubMed, Embase, MEDLINE, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Wanfang, Weipu on Dec 31, 2014.Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the association. A total of eight studies including 2,186 cases and 2,285 controls were involved in this meta-analysis. Results: The pooled results indicated the significant association between MIF -173G/C polymorphism and the risk of cancer for Chinese population (CC + CG vs GG: OR=1.14, 95%CI=1.02-127, pheterogeneity<0.01; P=0.023; CC vs CG+GG: OR=1.12, 95%CI=1.02-1.23, pheterogeneity<001; P=0.017;CC vs GG: OR=1.18, 95%CI=1.04-1.33, pheterogeneity<001; P=0.008; CG vs GG:OR=1.03, 95%CI=0.91-1.15, pheterogeneity<001; P=0.656; C vs G:OR=1.24, 95%CI=1.14-1.25, pheterogeneity<001; P<001). Subgroup analysis showed that in patients with "solid tumors", heterogeneity was very large (OR=0.94,95%CI=0.83-1.06,pheterogeneity=0.044; p=0.297). Within "non-solid tumors", the association became even stronger (OR=6.62, 95 % CI=4.32-10.14, pheterogeneity<0.001; p<0.001). Conclusions: This study suggested that MIF -173G/C gene polymorphism may increase increase cancer in the Chinese population.Furthermore, more larger sample and representative population-based casees and well-matched controls are needed to validate our results.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.64-71
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• 2015

Silica fume is generally adopted as admixture for Ultra High Strength Concrete (UHSC) owing to its remarkable contribution to the strength and durability but increases significantly the fabrication cost of UHSC. Accordingly, this study investigates the replacement of silica fume by blast furnace slag (BS) and fly ash (FA) in order to lower the fabrication cost of 80MPa-UHSC. To that goal, experiment is conducted on the mix proportions of mortar in terms of its binder combination, water-to-binder ratio (W/B) and unit binder content. Based on the experimental data, a mix design of concrete is derived and its properties are verified. The results reveal that a W/B of 21% and unit binder content of $720kg/m^3$ are appropriate to achieve 80MPa-UHSC using a binder composed of 60% of OPC, 30% of BS and 10% of FA. The properties of the corresponding UHSC are seen to be satisfactory with a slump flow of 715mm and compressive strength of 97MPa at 28days. The application of the binder combination derived in this study is analyzed to reduce the cost by 50% of binder compared to the mix using silica fume while realizing equivalent performance.

• Smart Structures and Systems
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• v.4 no.2
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• pp.221-232
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• 2008

This paper represents the final results of a research program sponsored by the European Commission through project WIND-CHIME ($\underline{W}$ide Range Non-$\underline{IN}$trusive $\underline{D}$evices toward $\underline{C}$onservation of $\underline{HI}$storical Monuments in the $\underline{ME}$diterranean Area), in which the possibility of using advanced seismic protection technologies to preserve historical monuments in the Mediterranean area is investigated. In the current research, the dynamic characteristics of two outstanding Mamluk-Style minarets, which similar minarets were reported to experience extensive damage during Dahshur 1992 earthquake, are investigated. The first minaret is the Qusun minaret (1337 A.D, 736 Hijri Date (H.D)) located in El-Suyuti cemetery on the southern side of the Salah El-Din citadel. The minaret is currently separated from the surrounding building and is directly resting on the ground (no vaults underneath). The total height of the minaret is 40.28 meters with a base rectangular shaft of about 5.42 ${\times}$ 5.20 m. The second minaret is the southern minaret of Al-Sultaniya (1340 A.D, 739 H.D). It is located about 30.0 meters from Qusun minaret, and it is now standing alone but it seems that it used to be attached to a huge unidentified structure. The style of the minaret and its size attribute it to the first half of the fourteenth century. The minaret total height is 36.69 meters and has a 4.48 ${\times}$ 4.48 m rectangular base. Field investigations were conducted to obtain: (a) geometrical description of the minarets, (b) material properties of the minarets' stones, and (c) soil conditions at the minarets' location. Ambient vibration tests were performed to determine the modal parameters of the minarets such as natural frequencies and mode shapes. A $1/16^{th}$ scale model of Qusun minaret was constructed at Cairo University Concrete Research Laboratory and tested under free vibration with and without SMA wire dampers. The contribution of SMA wire dampers to the structural damping coefficient was evaluated under different vertical loads and vibration amplitudes. Experimental results were used along with the field investigation data to develop a realistic 3-D finite element model that can be used for seismic risk evaluation of the minarets. Examining the updated finite element models under different seismic excitations indicated the vulnerability of such structures to earthquakes with medium to high a/v ratio. The use of SMA wire dampers was found feasible for reducing the seismic risk for this type of structures.