• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.947-953
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• 2012

In this study we investigated the manufacturing method for the activated carbon using the char from the pyrolysis of waste tire. The physical activation method using the steam in the fixed-bed quartz reactor was used for preparation of activated carbon. The primary experiment parameters are the activation temperature, activation time, heating rate, and the injection quantity of active agent. From the results of pore distribution of activated carbon, the micropore which was made in $850^{\circ}C$ of activation temperature, $5^{\circ}C$/min of heating rate, and 3 hours of activation time was developed in biggest quantity, and mesopore and macropore were developed in the biggest quantity too. The optimum conditions for producing the activated carbon using the pyrolysis residue were $850^{\circ}C$ of activation temperature, 3 hours of activation time, $5^{\circ}C$/min of heating rate, and 3 g $H_2O/char-g{\cdot}hr$ of active agent through this study. The produced activated carbon in these conditions showed that the potentiality of utilization as activated carbon because the BET specific surface area was $517.6m^2/g$ and total pore volume was $0.648cm^3/g$.

• Korean Journal of Plant Resources
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• v.23 no.5
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• pp.399-405
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• 2010

Rosa rugosa has been used as a folk medicine with various pharmacological properties for a long time in Asia. Recently, it has been reported that the extract of fractions from different parts of Rosa rugosa have various pharmacological effects on diverse diseases including diabetes, inflammatory diseases and tumor. We investigated effects of fructus extracts of Rosa rugosa(RRF) and semen extracts of this herb(RRS) on macrophage to evaluate the possibilities as a biological response modifier. We showed increased effects on tumoricidal activity, phagocytic activity, TNF-$\alpha$ and NO production in RRF-treated groups without direct tumor cell cytotoxicity. RRS-treated groups increased direct tumor cell cytotoxicity at high dose without tumoricial activity except increasing of TNF-$\alpha$ release. These results provide further possibilities for the beneficial immunomodulating effects of RRF on immune system with relatively larger safety margin rather than RRS.

• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.188-195
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• 1999

The fMRI signals are composed of many various signals. It is very difficult to find the accurate parameter for the model of fMRI signal containing only neural activity, though we may estimating the signal patterns by the modeling of several signal components. Besides the nose by the physiologic motion, the motion of object and noise of MR instruments make it more difficult to analyze signals of fMRI. Therefore, it is not easy to select an accurate reference data that can accurately reflect neural activity, and the method of an analysis of various signal patterns containing the information of neural activity is an issue of the post-processing methods for fMRI. In the present study, fMRI data was analyzed with the Independent Component Analysis(ICA) method that doesn't need a priori-knowledge or reference data. ICA can be more effective over the analytic method using cross-correlation analysis and can separate the signal patterns of the signals with delayed response or motion related components. The Principal component Analysis (PCA) threshold, wavelet spatial filtering and analysis of a part of whole images can be used for the reduction of the freedom of data before ICA analysis, and these preceding analyses may be useful for a more effective analysis. As a result, ICA method will be effective for the degree of freedom of the data.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.604-610
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• 2007

Characteristics of steam gasification and combustion of naphtha tar pitch, which is the bottom product of naphtha cracking process, were investigated by using the thermo gravimetric analyzer to develop the technology for obtaining syngas by using the naphtha tar pitch as a carbon source. Friedman's and Ozawa-Flynn-Wall method were used to calculate activation energy, reaction order and frequency factor of reaction rate constant for both of steam gasification and combustion. The activation energy of combustion of naphtha tar pitch based on the fractional conversion by Friedman's method was in the range of 41.58 ~ 68.14 kJ/g-mol when the fractional conversion level was in the range of 0.2~0.6, but 183.07~191.17 kJ/g-mol when the conversion level was 0.9~1.0, respectively. In case of steam gasification of naphtha tar pitch, the activation energy was in the range of 31.87~44.87 kJ/g-mol in the relatively lower conversion level (0.2~0.6), but 70.63~87.79 kJ/g-mol in the relatively higher conversion level (0.8~0.95), respectively. Those results exhibited that the steam gasification as well as combustion would occur by means of two steps such as devolitilization followed by combustion or gasification.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.7
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• pp.361-370
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• 2016

Effective acquisition technology is an important factor determining the competitiveness of companies(Roxas et al., 2011). Since the importance of technology transfer has been increased, there has been a growing interest in company, government, university and research institutes (Bozeman et al., 2015). Despite the national efforts for activating technology transfer, a lot of technology is still in universities and R&D center(Ockwell et al., 2009). The barriers of technology transfer are a main reason to inhibit the technology transfer. In order to be lower technology transfer barriers, it is necessary to derive the technology transfer broker based on social network analysis. However, most studies related to technology transfer broker had been focused on empirical study(Bozeman et al., 2015). Therefore, it is needed to suggest the method to grasp the opportunity that can lead to technology innovation based on analyzing and visualizing the network of technology transfer. The method in this study provides the company with the connectable path, technology transfer broker and strategy to classify the technology actor within the network. Finally, the method is applied to Global MVP for verifying the feasibility of method.

• Investigative Magnetic Resonance Imaging
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• v.3 no.1
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• pp.53-59
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• 1999

Purpose : To evaluate the usefulness of functional MR imaging (fMRI) for language mapping and determination of language lateralization. Materials and Methods : Functional maps of the language area were obtained during word generation tasks and decision task in ten volunteers (7 right handed, 3 left-handed). MR examinations were performed at 1.5T scanner with EPI BOLD technique. Each task consisted of three resting periods and two activation periods with each period of 30 seconds. Total acquisition time was 162 sec. SPM program was used for the postprocessing of images. Statistical comparisons were performed by using t-statistics on a pixel-by- pixel basis after global normalization by ANCOVA. Activation areas were topographically analyzed (p>0.001) and activated pixels in each hemisphere were compared quantitatively by lateralization index. Results : Significant activation signals were demonstrated in 9 of 10 volunteers. Activation signals were found in the premotor and motor cortices, the inferior frontal, inferior parietal, and mid-temporal lobes during stimulation tasks. In the right handed seven volunteers, activation of language areas was lateralized to the left side. Verb generation task produced stronger activation in the language areas and higher value of lateralization index than noun generation task or decision task. Conclusion : fMRI could be a useful non-invasive method for language mapping and determination of language dominance.

• Korean Chemical Engineering Research
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• v.47 no.2
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• pp.169-173
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• 2009

Effects of variations sulfur/accelerator ratio on cross-linking and thermal degradation behavior of NR/CR rubber compounds were studied using both dynamic DSC and non-isothermal TGA. DSC thermograms of the given samples were obtained with several different heating rates, and after cross-liked in DSC, TGA thermograms with the same samples also obtained. Kissinger analysis was applied to assess the activation energies for the cross-linking and thermal decomposition processes. Results showed that the formation and thermal decomposition reaction of the samples occurred in the overall temperature range of $120{\sim}180^{\circ}C$ and $350{\sim}450^{\circ}C$, respectively, exhibiting that data could be well-fittable by Kissinger method. Furthermore, formation activation energy by DSC was estimated as $83.0{\pm}5.0kJ/mol$, which was much smaller than that of degradation by TGA, $147.0{\pm}2.0kJ/mol$. From these results, it was considered that, although variations of sulfur/accelerator ratio in the present experiments affected little on the formation mechanism and/or thermal degradation, they could play roles as the catalysts which lower the activation energy of formation. Because of stabilization after formation reaction, however, they have no more effects on the lowering the activation energy, showing higher values when decomposition, caused by main-chain scissions.

• Clean Technology
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• v.29 no.4
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• pp.272-278
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• 2023

There is a lot of interest in methods for pollutants using adsorption, and recent research is being conducted to show that biochar can be used to remove organic and inorganic pollutants. In particular, wood waste as waste biomass requires a biomass recycling method, and a method to increase the adsorption capacity of biochar produced using wood waste is needed. Biochar is created by Hydrothermal carbonization (HTC) using, which uses low temperature and high pressure, has low energy consumption and does not require moisture removal pretreatment, and biochar is created through chemical activation using KOH, NaOH, and ZnCl₂ chemicals. The adsorption characteristics of biochar were determined by analyzing iodine adsorptivity, specific surface area, pore diameter, pore volume, pore distribution, and SEM according to the activation. The results of analyzing the selecting biochar by activating the biochar produced at HTC 300℃, 4 hr by KOH, NaOH, and ZnCl₂ chemicals, the specific surface area was 774~1.387 m²/g, showing a high specific surface area similar to activated carbon, and it was confirmed that micropores with an average pore diameter in the range of 21~24 Å were formed. As a result of SEM observation, the surface was uniform with a certain shape depending on activation. It was confirmed that one pore was developed and the number of pores increased.

• Journal of Korean society of Dental Hygiene
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• v.24 no.3
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• pp.219-227
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• 2024

Objectives: The pulp is the center of the tooth containing nerves and blood vessels. The condition in which the pulp becomes inflamed due to caries or periodontitis is called pulpitis. Pulpitis is a difficult-to-treat disease and causes peripheral nerve tissue changes and severe pain; however, the relationship between neuronal activity and voltage-gated sodium channel 1.7 (Nav1.7) expression in the trigeminal ganglion (TG) during pulpitis has not been well studied. In this study, we found that experimentally induced pulpitis activates Nav1.7 expression in the periphery, leading to neuronal overexpression in the TG. Thus, we sought to identify ways to regulate this process. Methods: Acute pulpitis was induced in rat maxillary molars by treating the pulp with allyl isothiocyanate (AITC). Three days later, in vivo optical imaging was used to record and compare neural activities in the TG. Western blotting was used to identify molecular changes in terms of the expression of extracellular signal-regulated kinase (ERK), c-Fos, transient receptor potential ankyrin 1 (TRPA1), and collapsin response mediator protein-2 (CRMP2) in the brain stem. Results: The results confirmed the neurological changes in the TGs of the pulpitis model, and histological and molecular biological evidence confirmed that increased Nav1.7 expression induced by pulpitis leads to pain. Furthermore, selective inhibition of Nav1.7 resulted in changes in neural activity, suggesting that pulpitis induces increased Nav1.7 expression, and that effective control of Nav1.7 could potentially reduce pain. Conclusions: The inhibition of overexpressed Nav1.7 channels may modulate nociceptive signal processing in the brain and effectively control pain associated with pulpitis.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.7-10
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• 2008

본 논문에서는 국내에서 DTV 전환에 대비한 기술적 보호조치 방안 마련을 위하여 기술적 보호조치의 방법들에 대하여 간략히 살펴보고 이를 바탕으로 유통활성화를 도모하기 위한 기술적 보호조치 방법을 제안하였다. 디지털 방송프로그램을 보호하기 위한 기술적 보호조치는 인터넷을 통한 불법유통을 방지하여 저작권자의 이익을 도모하려는 목적이나, 이로 인하여 방송프로그램 유통의 지나친 억제는 저작권자의 권익보호를 위하여 바람직하지 않다. 따라서 사용자가 보다 편리하고 저렴한 비용으로 방송프로그램을 재시청 및 재활용할 수 있도록 방송프로그램의 기술적 보호조치를 마련하는 것이 저작권자의 권익을 극대화 할 수 있다. 이러한 방법의 하나로 방송프로그램에 콘텐츠 보호선호 및 콘텐츠의 이용을 위한 연결정보를 포함하여 송출하고 방송수선단말에서 사적이용범위 내에서는 방송프로그램을 자유롭게 녹화 및 복사하여 시청할 수 있지만, 사적이용범위 밖으로 복사/전송 시에는 콘텐츠 연결정보만을 복사하고, 이를 재생할 때는 콘텐츠 연결정보를 이용하여 방송프로그램 유통서버로 연결하며, 유통서버와의 통신을 통하여 저렴하고 편리하게 방송프로그램을 사용할 수 있는 기술적 보호조치의 한 방법을 제안하였다.