• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.10C
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• pp.1032-1041
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• 2007

The global navigation satellite system (GNSS), which is the core technique for the location based service, adopts the direct sequence/spread spectrum (DS/SS) as its modulation method. The success of a DS/SS system depends on the synchronization between the received and locally generated pseudo noise (PN) signals. As a step in the synchronization process, the tacking scheme performs fine adjustment to bring the phase difference between the two PN signals to zero. The most widely used tracking scheme is the delay locked loop with early minus late discriminator (EL-DLL). In the ideal case, the EL-DLL is the best estimator among various DLL. However, in the band-limited multipath environment, the EL-DLL has tracking bias. In this paper, the timing offset range of correlation function is divided into advanced offset range (AOR) and delayed offset range (DOR) centering around the correct synchronization time point. The tracking bias results from the following two reasons: symmetry distortion between correlation values in AOR and DOR, and mismatch between the time point corresponding to the maximum correlation value and the synchronization time point. The former and latter are named as the type I and type II tracking bias, respectively. In this paper, when the receiver has finite bandwidth in the presence of multipath signals, it is shown that the type II tracking bias becomes a more dominant error factor than the type I tracking bias, and the correlation values in AOR are not almost changed. Exploiting these characteristics, we propose a novel tracking bias mitigation scheme and demonstrate that the tracking accuracy of the proposed scheme is higher than that of the conventional scheme, both in the presence and absence of noise.

• Journal of Korean Society for Geospatial Information Science
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• v.6 no.1 s.11
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• pp.11-17
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• 1998

Recently, 3D GIS based on 3D geo-processing methodology and Internet environment are emerging issues in GIS fields. To design and implement 3D GIS, the strategic linkage of Java and VRML is first regarded: 3D feature format definition in the passion of conventional GIS including aspatial attributes, 3B feature indexing, 3D analytical operators such as selection, buffering, and Near, Metric operation such as distance measurement and statistical description, and 3D visualization. In 3D feature format definition, the following aspects are implemented: spatial information for 3D primitives extended from 2D primitives, multimedia data, object texture or color of VRML specification. DXF-format GIS layers with additional attributes are converted to 3D feature format and imported into this system. While, 3D analytical operators are realized in the form of 3D buffering with respect to user-defined point, line, polygon, and 3D objects, and 3D Near functions; furthermore, 'Lantern operator' is newly introduced in this 3D GIS. Because this system is implemented by Java applet, any client with Java-enable browser including VRML browser plug-in can utilize the new style of 3D GIS function in the virtual space. Conclusively, we present prototype of WWW-based 3D GIS, and this approach will be contribute to development of core modules on the stage of concept establishment and of real application model in future.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.388-402
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• 2017

This paper presents an enhancement of the two-step floating catchment area (2SFCA) method for measuring spatial accessibility between three age groups, addressing the problem of uniform access within the catchment by applying multiple impedance function to account for distance decay and by applying weights to different age groups to account for medical service preference. The enhancement is provided to be another special care of the gravity model. When applying this modified three-step floating catchment area to measure the spatial access to emergency medical services in a study area, Chungnam province in South Korea, we find that it reveals the variation of spatial accessibility patterns between cities and rural areas and delineates more spatially explicit medical service shortage areas in southern Chungnam areas, especially remoted local rural areas. Finally, this method may be used to help the health and medical service divisions and the state departments improve designation of medical shortage areas. From the discussions, it is easy to implement in planning spatial policies of medical service and straightforward to be used as a basic, but core element for health and medical strategies in the province.

• Cartoon and Animation Studies
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• s.43
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• pp.1-22
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• 2016

So far, the Studio Ghibli's major masterpieces, and have been studied extensively from mythical and psychological perspectives due to the films' intrinsic symbolism within their characters and events. However, there have been insufficient in-depth research on the types of love the two works have. Therefore, this study will focus on how the types of love in the two animations mirror the concept of love in Plato's theory of Eros through the analysis of two films' characters. The desire for memory and recovery can be seen in , and glimpses of each phase of aim towards changes in physical appearance can be shown in . These describe the function and the purpose of Eros that Plato states in Socrates' terms in Phaedrus and Symposium. Plato ultimately defined Eros as a spirit that leads to the world of Ideas and suggested the five stages of love that are divided in accordance with the ultimate purpose and attitude of mankind towards Eros. The cognition area, changes in appearance of the characters and spatial ranks in and critically reveal such core concepts of the theory of Eros. It is noteworthy that the two works show the origin of the most universal ideology of the West. These two animation films are particularly significant in terms of that they reflect the western epistemology while covering exclusive and covert ethnic emotions.

• Journal of Life Science
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• v.25 no.1
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• pp.1-7
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• 2015

Cyclin D is a member of the cyclin protein family, which plays a critical role as a core member of the mammalian cell cycle machinery. D-type cyclins (D1, D2, and D3) bind to and activate the cyclin-dependent kinases 4 and 6, which can then phosphorylate the retinoblastoma tumor suppressor gene products. This phosphorylation in turn leads to release or derepression of E2F transcription factors that promote progression from the G1 to S phase of the cell cycle. Among the D-type cyclins, cyclin D3 encoded by the CCND3 gene is one of the least well studied. In the present study, we have investigated the biochemistry of the proteolytic mechanism that leads to loss of cyclin D3 protein. Treatment of human prostate carcinoma PC-3-M cells with lovastatin and actinomycin D resulted in a loss of cyclin D3 protein that was completely reversible by the peptide aldehyde calpain inhibitor, LLnL. Additionally, using inhibitors for various proteolytic systems, we show that degradation of cyclin D3 protein involves the $Ca^{2+}$-activated neutral protease calpain. Moreover, the half-life of cyclin D3 protein half-life increased by at least 10-fold in PC-3M cells in response to the calpain inhibitor. We have also demonstrated that the transient expression of the calpain inhibitor calpastatin increased cyclin D3 protein in serum-starved NIH 3T3 cells. These data suggested that the function of cyclin D3 is regulated by $Ca^{2+}$-dependent protease calpain.

• Journal of Preventive Medicine and Public Health
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• v.27 no.2 s.46
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• pp.274-285
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• 1994

The effects of resin on the respiratory health have been investigated in 309 workers from four iron and steel foundries and the results compared with those from 122 workers who were not significantly exposed to resin gas and silica dust at the same industries. Phenol-formaldehyde resin was used in the core making and molding processes and workers were exposed to their decomposition products as well as to silica dust containing particulates. The subjects were grouped according to formaldehyde, dust and other gas exposures, and smoking habits were considered also in thi analysis. Standardized respiratory symptom questionnaire was administered by trained interviewers. Chest radiograph, pulmonary funtion tests, and methacholine challenge tests were done. Environmental measurements at the breathing zone were carried out to determine levels of formaldehyde, respiable dust and total dust. Foundry workers had a higher prevalence of symptoms of chronic bronchitis with chronic phlegm and chronic cough when exposed to dust. Exposure to gas was significantly associated with lowered $FEV_1$ and obstructive pulmonary function changes. Exposure to formaldehyde and phenol gas was associated with wheezing symptom among workers, but $FEV_1$ changes after methacholine challenge were not significantly different among different exposure groups. When asthma was defined as the presence of bronchial hyperreactivity with more than 20% decrease in $FEV_1$ after methacholine challenge, 17 workers out of 222 tested had asthma. Fewer asthmatic welters were found among groups exposed to formaldehyde, gas and dust, which indicates a healthy worker effects ill a cross-sectional study. The concentration of formaldehyde gas ranged from 0.24 to 0.43 ppm among studied foundries. The authors conclude that formaldehyde and phenol gas from combusted resin is probably the cause of asthmatic symptoms and also a selection force of those with higher bronchial reactivity away from exposures.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.3
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• pp.221-230
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• 2006

Recently, the need for esthetic results has increased the interest for all-ceramic crown prosthesis. Furthermore, the development of zirconium core via CAD/CAM system has allowed the all ceramic restorations to be applied to almost all fixed prosthesis situations. But, the increased strength has been reported to increase in proportion with the bond strength of cement, and recently, the tribochemical system which increases the bond strength through, silica coating and silanization has been introduced. The purpose of this study was to compare the $Rocatec^{TM}$ system and $CoJet^{TM}$ system with the traditional acid etching and silanization method of the irconium based ceramic. The surface character was observed via SEM(X2000), and the bond strength with the resin cement were measured. 50 In-Ceram Zirconia (Adens, Korea) discs were fabricated and embedded in resin, group 1 was treated with glass-bead blasting and cleaning, group 2 was treated with 20% HF for 10 minutes and silanized, group 3 was treated with the $Rocatec^{TM}$ system, and group 4 was treated with the $CoJet^{TM}$ system. Each group was comprised of 10 specimens. The specimens were cemented to a $3mm{\times}5mm$ resin block with Super-Bond C&B. The shear bond strength was measured with the $Instron^{(R)}$ 8871 at a crosshead speed of 0.5mm/min. The results were as follows. 1. According to SEM results, there were little difference between group 1 & group 2, but in group 3 and 4, silica coating was detected and there was increase in surface roughness. 2. The shear bond strength decreased in the order of group 3(46.28MPa), group 4(42.04MPa), group 2(31.56MPa), and group 1(27.46MPa). 3. There was significant differnce between group 1&2 and group 3&4(p<0.05). From the results above, it can be considered that the conventional method of acid etching and silane treatment cannot increase the bond strength with resin cements, and that by applying the tribochemical system of $Rocatec^{TM}$ system and $CoJet^{TM}$ system, we can achieve a stronger all ceramic restoration. Further studies on surface treatments to increase the bond strength are thought to be needed.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.1
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• pp.13-25
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• 2000

Optimal Pressable Ceramic is one of the all-ceramic restorations with a shaded translucent pressed core and layering porcelains. The purpose of this study was to evaluate the marginal fidelity according to margin types and measurement sites, and to evaluate fracture strength according to margin types. Twenty seven OPC crowns made according to 3 types of cervical finishing lines were used in this study. Marginal gaps were measured before and after cementation. A Steromicroscope(SZ-ST(R), Olympus, Japan) was used to measure the space between the margin of OPC crown and the finishing line of metal model. Marginal gaps were measured at the labial, mesial, lingual and distal site, which were demonstrated in advance. Fracture strength testing was carried out using an Instron(Model M100EC, Mecmesin, England) at a cross head speed of 5 mm/min. All crowns were loaded until catastrophic failures occurred. The result were as follow: 1. In comparison according to variable margin before cementation, the marginal gap were increased in chamfer margin($47.50{\pm}18.39{\mu}m$), $120^{\circ}$shoulder margin ($55.21{\pm}14.4{\mu}m$) and $90^{\circ}$shoulder margin($71.18{\pm}13.30{\mu}m$) in ascending order, and there were significant differences between chamfer margin and $90^{\circ}$shoulder margin, $120^{\circ}$shoulder margin and between $120^{\circ}$shoulder margin and $90^{\circ}$shoulder margin respectively(p<0.05). 2. In comparison according to variable margin after cementation, the gap discrepancies were increased in chamfer margin($60.78{\pm}30.37{\mu}m$), $120^{\circ}$shoulder margin($66.67{\pm}11.18{\mu}m$) and $90^{\circ}$shoulder margin($85.78{\pm}17.23{\mu}m$) in ascending order, but there was significant difference only between chamfer margin and $90^{\circ}$shoulder margin(p<0.05). 3. Labio-lingual points showed a better marginal fidelity than that of proximal point(p<0.05). 4. Chamfer margin($48.76{\pm}8.45kgf$) showed higher fracture strength than $120^{\circ}$ shoulder margin($40.57{\pm}7.90kgf$) and $90^{\circ}$ shoulder margin(32.7.90kgf) (p<0.05), but there was significant difference only between chamfer margin and $90^{\circ}$ shoulder margin(p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.86-92
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• 2014

Cordycepin is the major functional component of Cordyceps species and is widely used in traditional oriental medicine. Cordycepin has been shown to possess many pharmacological properties, such as enhancement of immune function along with anti-inflammatory, antioxidant, anti-aging, and anti-cancer effects. Here, we investigated the inhibitory effects of cordycepin on cell migration and invasion, which are two critical cellular processes that are often deregulated during metastasis, using HCT116 human colorectal carcinoma cells. According to our data, cordycepin at non-cytotoxic concentrations markedly inhibited the motility and invasiveness of HCT116 cells in a time-dependent manner. RT-PCR and Western blotting results indicated that cordycepin reduced the levels of claudin proteins, which are major components of tight junctions (TJs), and induced tightening of TJs. Cordycepin also attenuated the expression and activities of matrix metalloproteinases (MMPs)-2 and -9, whereas levels of tissue inhibitor of metalloproteinases (TIMPs)-1 and -2 were simultaneously elevated. These findings suggest that cordycepin reduces the migration and invasion of HCT116 cells by modulating the activities of TJs and MMPs.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.157-168
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• 2014

In buildings on the street, indiscriminate redevelopment are being made by overlooking the relationship with surrounding landscape to create their own unique meaning, due to industrialization progressed rapidly with human needs of longing for something constantly. Selection and methods of two plans, conservation and utilization should be required, considering heritage values on industrial buildings which are being lost and aged in this redevelopment higher. The attempt for the use of modern industrial heritage becomes a hot topic, and several experimental challenges are being made. However, there are rather many cases of causing industrial buildings' depreciation and one-size-fits-all reproduction performance as it applies other examples as standards by recognizing the reproduction of modern industrial heritage as one trend, not focusing on the trend of the times or paradigm, what the times want. To minimize these problems, we focus on how to utilize industrial buildings beyond the importance of industrial buildings' reproduction, considering the quality of local residents' life as well as the expected effect obtainable due to security of local identity and reproduction of buildings, focusing on the concept of community design that offers and forms a way of community life as the design of shares based on unspecified individuals' common life. Community design's core can be called to have diversity rather than undifferentiated unity by pursuing whole unification, since local residents become those who plan design and all people participate in it. In addition, community design achieves integration with other fields as an enlarged design area without limiting in an environmental area, by making indigenously natural characteristics combined with cultural factors in one context so that people may understand the flow of the place. The importance of effects acquired from modern industrial heritage's reproduction has well-known, and the attempt for utilizing aged heritage as a new value and a function has constantly been made. Now, it's time to focus on how long it lasts through this method, rather than modern industrial heritage's reproduction itself. There can be a significance in this study in proposing methodological solutions on modern industrial heritage's reproduction, not to cause depreciation of industrial buildings by recognizing contemporary trends and uniform regeneration performance, multifaceted research is needed for creative, effective development on modern industrial heritage which will occur constantly.