• Journal of Korean Society for Atmospheric Environment
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• v.18 no.4
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• pp.285-295
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• 2002

In this study, several types of gravimetric methods (such as high, medium, low, and ultra low volume sampling methods) were applied to determine suspended particulate matter concentrations in both ambient and indoor environments. Comparative evaluations were undertaken with SPM data obtained using a variety of samplers (TSP, PM10, and PM4.0) at different sampling flow rates. Correlation coefficients between TSP and PM10 concentrations measured at different flow rates fell in the range of 0.73∼0.94 (n=40). In addition, correlation coefficients for PM concentrations measured by different TSP samplers were in the range of 0.90∼0.95 (n=36 or n=38), while 0.77∼0.91 (n=38) for PM10 samplers. Correlation analysis was also conducted on indoor monitoring data that were measured using ultra-low-volume samplers at both different or identical flow rates. The correlation coefficients were in the range of 0.98∼0.99 (n=38) between TSP and TSP and 0.92∼0.94 (n=38) between TSP and PM10. The mean ratio for high volume PM10 to TSP concentration that was monitored at identical flow rates in the ambient air appeared to be 0.72. The mean ratios of PM10 to TSP and PM4.0 to TSP observed with identical flow rates at indoor environments were 0.47 and 0.40. The results of this study may provide empirical information concerning the compatability of aerosol data obtained by gravimetric sampling methods at different flow rates.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.575-582
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• 2016

The purpose of this study was to analyse undergraduate medical students' perception of the complementary and alternative medicine(CAM) and Korean medicine. A total of 409 undergraduate medical students participated in the survey. Methodologically, descriptive statistics, MANOVA and logistic regression analysis were conducted. First grade students had more positive perception of CAM and Korean medicine than others. There were no significant differences in the perception of CAM in terms of students' grade and gender(affective attitude, compatability, effectiveness, intention to adoption). However, there was gender difference in perception of Korean medicine. Also, the result showed that students' perception of effectiveness had influence whether they recognize CAM and Korean medicine as medicine or not. Based on results, this study suggest that medical school should develop the curriculum that improve students decision-making ability and critical capacity, especially for lower grades, so that stdents can give reasonable advice for patients' needs.

• Journal of the Korea Safety Management & Science
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• v.10 no.3
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• pp.167-181
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• 2008

There are lack of labour and increase in logistics costs due to rapid change in logistics environments and the demand for logistics. The reality is that over spending on logistics costs are getting worse due to lack of logistics standardization. An example will be excessive logistics costs caused by unsatisfactory use of logistics equipments in wholesale markets. The logistics efficiency is falling due to delays in using logistics equipments and standardization. Therefore, there needs standardization of logistics functions and unit of handling in each stage from packing, unloading, storage, transporting, logistics information and needs logistics standardization on equipments, machineries used for the above. Standard unified with standardization is called specification and if standardization is applied broadly in manufacturing or processing, inspection than each process in terms of production can be managed rationally and labour skills will improve and product quality will be evenly maintained and compatability of each part in terms of assembly will be maintained thus materials and labour could be saved thus results in increasing productivity and lowering production costs. Also, if it is applied in industry at state-level then there will be rationalization in consumption in circulation as in purchase of raw materials, sales of products, purchase of products by consumers and contribute in improving compatibility and fair transactions. This paper is aimed to help in first solving factors affecting the most in improving logistic efficiency among unit load system and logistic hollowization, standardizing logistics base, standardizing logistics information. The study conducted surveys on limited companies but hope that in the future the target companies can be divided further into types, industries and conduct more demonstrative analysis.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.16.1-16.1
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• 2011

$TiO_2$ is a promising material for gas sensors. To achieve high sensitivities, the material should exhibit a large surface-to-volume ratio and possess the high accessibility of the gas molecules to the surface. Accordingly, a wide variety of porous $TiO_2$ nanomaterials synthesized by wet-chemical methods have been reported for gas sensor applications. Nonetheless, achieving the large-area uniformity and comparability with well-established semiconductor production processes of the methods is still challenging. An alternative method is soft-templating which utilizes nanostructured inorganic or organic materials as sacrificial templates for the preparation of porous materials. Fabrication of macroporous $TiO_2$ films and hollow $TiO_2$ tubes by soft-templating and their gas sensing applications have been reported recently. In these porous materials composed of assemblies of individual micro/nanostructures, the form of links or necks between individual micro/nanostructures is a critical factor to determine gas sensing properties of the material. However, a systematic study to clarify the role of links between individual micro/nanostructures in gas sensing properties of a porous metal oxide matrix is thoroughly lacking. In this work, we have demonstrated a fabrication method to prepare highly-ordered, embossed $TiO_2$ films composed of anatase $TiO_2$ hollow hemispheres via soft-templating using polystyrene beads. The form of links between hollow hemispheres could be controlled by $O_2$ plasma etching on the bead templates. This approach reveals the strong correlation of gas sensitivity with the form of the links. Our experimental results highlight that not only the surface-to-volume ratio of an ensemble material composed of individual micro/nanostructures but also the links between individual micro/nanostructures play a critical role in evaluating the sensing properties of the material. In addition to this general finding, the facileness, large-scale productivity, and compatability with semiconductor production process of the proposed fabrication method promise applications of the embossed $TiO_2$ films to high-quality sensors.

• The Journal of Information Systems
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• v.25 no.4
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• pp.87-104
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• 2016

Purpose As the smartphone market arrived at its saturation, from world leading information and communications technologies (ICT) businesses to startups, companies are competing to develop innovative wearable device products and suitable contents. Utility, technology, design, price, and various killer contents development targeting every customer's need should be considered for a success in the wearable device market. Design/methodology/approach Prior studies on innovation technology of ICT field have mainly focused on the innovation diffusion theory, expectation confirmation theory, and technology acceptance model, this study suggested the innovation resistance factors of adopting the smart wearable devices based on the innovation resistance model and theory of perceived risk. The model comprises the following two characteristics factors: 1) innovation characteristics which include perceived relative advantages, perceived compatability, perceived complexity, and perceived risk, 2) consumer characteristics which include attitudes towards innovation and existing products (i.e., mobile devices and analog watches). This study developed an extended innovation resistance model to explain the intention to acceptance of wearable devices consumers and collected 284 online survey responses from the non-consumers of the wearable devices. Findings The findings of this study suggest that perceived relative advantage, perceived compatibility, perceived complexity, perceived risk, attitudes towards innovation and attitudes towards existing analog watches affected the innovation resistance which has negative influence on the intention to adoption of wearable devices.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.3
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• pp.258-264
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• 2004

In this paper, MMIC double balanced star mixer for 40 ㎓ was implemented on GaAs substrate with backside vias. In the design of the MMIC mixer, the design of balun and diode was required. A novel balun structure using microstrip to CPS was presented. The 40 ㎓ balun was designed based on the design experience of the scale-down balun by 2 ㎓. The balun may be suitable for fabrication in MMIC process with backside via and can easily be applied for DBM(Double Balanced Mixer). A Schottky diode was designed and implemented using p-HEMT process considering the compatability with other high frequency MMIC's fabricated on p-HEMT base process. Finally, the double balanced star mixer was fabricated using the balun and the p=HEMP Schottky diode. The measured performance of mixer shows 30 ㏈ conversion loss at 18 ㏈m LO power. This insufficient performance is caused by the unwanted diode at AlGaAs junction in vertical structure of p-HEMT. If the p-HEMT's gate is recessed to AlGaAs layer, and so the diode is eliminated, the mixer's performances will be improved.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.193-197
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• 2003

As one of the core technologies in the field of the optical communication with WDM, the optical cross connector with movements of micro mirrors is getting important day by day. The packaging structure of 2-dimensional NxN MOEMS switch should be determined by the harmonization of the following items such as the geometrical compatability between optical and structural components, the characteristics of optical input and output parts with device, and the electrical performance for the operation of micro mirrors. Therefore, the packaging process could be defined as the integrated technology completed by the optical and electrical science and the material science for the understanding of its thermo-mechanical properties with packaging materials. In the present study, the harmonization between the optical and structural components as well as the optical characteristics of lens system used will be investigated.

• Polymer(Korea)
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• v.24 no.6
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• pp.869-876
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• 2000

In order to improve the cell-compatability of poly(L-lactide-co-glycolide) (75 : 25 by mole ratio of lactide to glycolide, PLGA) surfaces, the physicochemical treatments have been demonstrated. Chemical treatments were 70% perchloric acid. 50% sulfuric acid and 0.5 N sodium hydroxide solution and physical methods were corona and plasma treatment. The water contact angle of surface treated PLGA decreased from 73$^{\circ}$ to 50~60$^{\circ}$, i.e., increased hydrophilicity, due to the introduction of oxygen-containing functional group onto PLGA backbone by the measurement of an electron spectroscopy for chemical analysis. It could be observed that the adhesion and growth of fibroblast cell on physicochemically treated PLGA surfaces, especially perchloric acid treated PLGA surface, were more active than on the controt. In conclusion, it seems that surface wettability as hydrophilicity of PLGA plays an important role in cell adhesion, spreading and growth.

• Journal of KIISE:Information Networking
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• v.32 no.2
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• pp.236-243
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• 2005

Most of the existing legacy DSL networks, about 80 million lines world-widely, adopted ‘ATM(Asynchronous Transfer Mode) over DSL’protocol architecture for the effective interworking with the ATM-based regional backbone networks and for the effective support of native ATM-based multimedia application services. Recently, however, the regional backbone networks are moving towards Metro Ethernet networks, instead of the ATM networks, and most of the current multimedia applications are If-based, not native ATM-based. These environmental changes push the architecture of DSL networks to be accordingly changed, and the‘Ethernet over DSL’protocol architecture, instead of existing‘ATM over DSL’, is tried to be applied to the implementation of next generation DSL networks such as VDSL(Very high-rate DSL) . In this paper, we propose two different implementation models for next generation DSL networks in Metro Ethernet backbone environments, respectively EA(Ethernet-to-ATM) implementation model and RE(Ethernet-to-Ethernet) implementation model. And, a comparative analysis focused on the performance and the backward compatability with the legacy DSL networks will be presented.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.3102-3107
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• 2013

Inorganic pigments were prepared from $Al_2O_3$, CoO, $Cr_2O_3$, ZnO, $SrO_2$ and Kaolin. The pigment was prepared through the processes of mixing and crushing of the raw materials, sintering, milling and drying. The color of the pigments was changed from blue to green as $Cr_2O_3$ contents in the pigment increased. The color became brighter irrespective of the pigment composition as pigment particle size became smaller. Maximum sintering temperature was the most suitable at around $1,250^{\circ}C$. In the test of compatability between the pigment and glaze, the color became close to green as $Cr_2O_3$ contents in the pigment increased, and became close to blue as CoO contents increased.