• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.271-278
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• 2004

This paper shows our experiment is performed to understand the exposure tendency of $^{137}Cs$ according to the height of area and also, to supplement it by considering chemical characters of $^{137}Cs$ exposed to the soil. The samples we use for this experiment are from the general flat area of Yeonggwang county where it has NPPs, the high places of Keumjung & Bulgap mountains, and Naejan mountain where it is quite far from the NPPs. The data from this experiment show that the exposure of $^{137}Cs$ is not harmful since its range is around 252 Bq/kg-dry in most of sampled soils such as from the general flat area, the high place of Keumjung mountain where is 2 km away from the NPPs, the other high place of Bulgap mountain where is about 20 km away from the NPPs, and Naejan mountain where it is far from the NPPs. Not like the general flat area, however, the data show that the higher the area is the more $^{137}Cs$ is exposed. That is, at the top of mountains, the more $^{137}Cs$ is exposed compared to at the bottom area. It is almost $2{\~}6$ times more than the general flat area of Yeonggwang county where it has NPPs. The data also show that the spread of $^{137}Cs$ is deeply related to the geographical(the height of area, rainfall, etc..) factors and chemical factors of soils. As the geographical factors, there are far more chances to be exposed of $^{137}Cs$ at the high area of mountains through the air compared to at lower area and therefore, we can get more high-leveled readings of $^{137}Cs$ at the high area while it is low-leveled ones at the general flat area even if both of them have the same soil conditions. Regarding the chemical factors of soil, it is clarified that the CEC is the key factor. The CEC means the capability of sticking $^{137}Cs$ accumulated into the soil. Hence, the more CEC it has the more high-leveled readings of $^{137}Cs$ we get under the same geographical condition.

• Progress in Medical Physics
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• v.25 no.3
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• pp.123-127
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• 2014

The Cs-137 irradiator is widely used to irradiate biological samples for radiobiological research. To obtain the accurate outcomes, correct measurements of the delivered absorbed dose to a sample is important. The IAEA protocols such as TRS-277 and TRS-398 were recommended for the Cs-137 reference dosimetry. However in TRS-398 protocol, currently known as the most practical dosimetry protocol, the quality factor ($k_{Q,Q_0}$) for Cs-137 gamma rays is not suggested. Therefore, the use of TRS-398 protocol is currently unavailable for the Cs-137 dosimetry directly. The calculation method previously introduced for high energy photon beams in radiotherapy was used for deriving the Cs-137 beam qualities ($k_{Q,Q_0}$) for the 15 commercially available farmer type ionization chambers in this study. In conclusion, $k_{Q,Q_0}$ values were ranged from 0.998 to 1.002 for Cs-137 gamma rays. These results can be used as the reference and dosimeter calibrations for Cs-137 gamma rays in the future radiobiological researches.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.12A
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• pp.1319-1332
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• 2004

Multicarrier direct sequence code-division multiple access CDMA(MC DS-CDMA) is an attractive technique for achieving high data rate transmission even if the potentially large peak-to-average power ratio(PAPR) is an important factor for its application. On the other hand, code select CDMA(CS-CDMA) is an attractive technique with constant amplitude transmission of multicode signal irregardless of subchannels by introducing code selection method. In this paper we propose a new multiple access scheme based on the combination of MC DS-CDMA and CS-CDMA. Proposed scheme, which we called MC CS-CDMA, includes the sutclasses of MC DS-CDMA and CS-CDMA as special cases. The performance of this system is investigated for multipath Sequency selective fading channel and maximal ratio combining with rake receiver. In addition the PAPR of proposed system is compare with that of both MC BS-CDMA and CS-CDMA. Simulation results show that proposed system improves PAPR reduction than MC DS-CDMA at the expense of the complexity of receiver and the number of available non. Also, the numerical result shows that the proposed system is better performance than MC DS-CDMA due to the increasing processing gain and the number of time diversity gain.

• Journal of Science and Technology Studies
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• v.18 no.2
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• pp.43-93
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• 2018

The concept of citizen science(CS) is defined as "scientific work carried out by citizens." Here, 'citizen' means someone who has knowledge of everyday life, regardless of whether they have formal expertise in a related field. This definition may encompass scientists, as many scientists participate in scientific democracy and use their expertise in a citizen-oriented manner. That work is derived from their citizenship, so their scientific work is CS. CS in Korea has expanded from the Korea Pollution Research Institute, which was founded in 1982, to the Center for Democracy in Science & Technology, which was founded in 1997. Furthermore, in recent years, government agencies have started using CS approach. In this paper, I introduce Korean CS and examine its accomplishments and difficulties through eight cases. I show that Korea's CS activities have made a significant impact on Korean society and the experience of these activities has implications for the future directions of CS. I do so by examining four modes of CS and explore practical messages for more varied roles of CS. Until now CS has been mainly considered in the context of "CS as education" or "CS as movement" in Korea. However, governance and the platform mode of social decision-making or research, though still rare, have recently emerged as additional CS activities. Although it cannot be said with certainty that CS is better, it is undoubtedly better the more varieties of its modes coexist. The four types of CS will contribute individually or complementarily to social learning. Thus, because of its distinctive potential, CS is not exhausted by the supplementary concept of science.

• Journal of Sensor Science and Technology
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• v.9 no.5
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• pp.341-349
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• 2000

CsI(Br) single crystals doped with 1, 3, 5 or 10 mole% $Br^-$ ions, as an activator, were grown by Czochralski method. The lattice structure of grown CsI(Br) single crystal was bcc and its lattice constant was $4.568\;{\AA}$. The absorption edge of the CsI(Br) single crystals was observed at 243 nm. The spectral range of the luminescence excited by 243 nm of wavelength was $300{\sim}600\;nm$, and its peak emission appeared at 440 nm. The luminescence intensity was maximum when CsI(Br) was doped with 3 mole % $Br^-$ ions. The energy resolutions of the CsI(Br) scintillator doped with 3 mole % $Br^-$ ions were 15.0% for $^{137}Cs$(662 keV), 13.1% for $^{54}Mn$(835 keV), and 18.0% and 6.3% for $^{22}Na$(511 keV and 1275 keV), respectively. The decay curves had fast and slow components, and the fast component was about 41 ns independent on the concentration of the $Br^-$ ions. The time resolution of CsI(Br) scintillators decreased with increasing of the concentration of $Br^-$ ions.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.1-12
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• 2011

To improve the mechanical properties, such as durabilities and antioxidative characteristics, the covalently cross-linked (CL-) SPEEK (sulfonated polyether ether ketone)/Cs-substituted HPA (heteropoly acid) organic-inorganic composite membranes (CL-SPEEK/Cs-HPAs), have been intensively investigated. The composite membrane were prepared by blending cesium-substituted HPAs (Cs-HPAs), including tungstophosphoric acid (TPA), molybdophosphoric acid (MoPA), and tungstosilicic acid (TSiA) with cross-linking agent content of 0.01 mL. And composite electrolytes composed of Cs-HPAs, prepared by immersion (imm.) and titration (titr.) methods to increase the stability of HPAs in water, were applied to polymer electrolyte membrane electrolysis (PEME). As a result, the proton conductivity of Cs-substituted composite membranes increased rapidly over $60^{\circ}C$ but mechanical properties, such as tensile strength, decreased in accordance with added Cs content. The bleeding-out of Cs-TPA membranes by titration method (50 vol.% Cs) decreased steadily to 2.15%. In the oxidative stability test by Fenton solution, the durability of membranes with Cs-HPA significantly increased. In case of CL-SPEEK/ Cs-TPA membrane, duration time increased more than 1200 hours. It is expected that even though CL-SPEEK/Cs-MoPA membrane shows the high proton conductivity, electrocatalytic activity and cell voltage of 1.80 V for water electrolysis, the CL-SPEEK/Cs-TPA (imm.) is more suitable as an alternative membrane in real system with the satisfactory proton conductivity, mechanical properties, anti-oxidative stability and cell voltage of 1.89 V.

• Journal of Oral Medicine and Pain
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• v.48 no.3
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• pp.87-95
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• 2023

Purpose: To quantify the relationship between perceived pain intensity and psychological variables in a sample of participants with temporomandibular disorder, with or without central sensitization (CS). Methods: A cross-sectional study with nonprobability convenience sampling was conducted from January 1, 2022, to June 30, 2023. Pain intensity (Numeric Pain Rating Scale), anxiety (State-Trait Anxiety Questionnaire, STAI), catastrophizing (Pain Catastrophizing Scale, PCS), perceived stress (Perceived Stress Scale, PSS), and sleep quality (Pittsburgh Sleep Quality Index, PSQI) were assessed. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 20.0 (IBM Co.), which included descriptive and normality analyses and the calculation of strength of multiple correlational regression. Results: A total of 52 (n=34 female 65.4%; n=18 male 34.6%) subjects with diagnosis of temporomandibular disorders (TMD) were finally included. A total of 26 participants (n=26, 50.0%) were cases suffered from CS (TMD-CS mean=46.62±11.24) while the remaining participants (n=26, 50.0%) were the controls (TMD-nCS mean=26.77, standard deviation [SD]=8.42). The pain intensity was moderate in both groups TMDCS (mean=7.62, SD=0.83) and TMD-nCS (mean=7.05, SD=0.86), anxiety (TMD-CS STAI mean=53.27, SD=11.54; TMD-nCS STAI mean=49, SD=11.55), catastrophizing (TMD-CS PCS mean=46.27, SD=9.75; TMD-nCS PCS mean=26.69, SD=4.97), perceived stress (TMDCS PSS mean=30.35, SD=4.91; TMD-nCS PSS mean=26.12, SD=6.60) and sleep quality (TMD-CS PSQI mean=15.81, SD=3.65; TMD-nCS PSQI mean=12.77, SD=2.76) levels were measured in both groups. In TMD-CS and TMD-nCS, higher anxiety levels were moderately and significantly associated with greater pain intensity β=0.4467 (t=2.477, p=0.021) and β=0.5087 (t=2.672, p=0.014). Nevertheless, catastrophizing, perceived stress and sleep quality were not associated to pain intensity in neither of group. Conclusions: In both TMD-CS and TMD-nCS patients, elevated anxiety levels were moderately and significantly associated with increased pain intensity. However, heightened levels of pain catastrophizing, perceived stress, and poor sleep quality were not significantly associated with increased pain intensity in either of the two analyzed groups.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.26-27
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• 2004

This study was conducted to evaluate the value of chicken keel cartilage as a source of mucopoly-saccharide-protein containing chondroitin sulfate (CS) and to find the optimum extraction conditions. The hot water extraction and alcalase hydrolysis methods were performed for extraction mucopolysaccharide in lyophilized chicken keel cartilage. The most efficient condition was hydrolysis with 2 % alcalase in 10 volumes of distilled water for 120 min. The yield of hydrolysate and CS content were 75.87 % and 25.61 %, respectively. For further separation of CS from hydrolysate by alcalase, ethanol precipitation was performed. The yield of ethanol precipitate and its CS content were 21.41 % and 46.31 %, respectively.

• Toxicological Research
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• v.26 no.3
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• pp.163-170
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• 2010

Cyclosporine A (CsA) is a potent immunosuppressor that is widely used in transplant surgery and the treatment of several autoimmune diseases. However, major side effects of CsA such as nephrotoxicity, hepatotoxicity, neurotoxicity and cardiovascular diseases have substantially limited its usage. Although molecular mechanisms underlying these adverse effects are not clearly understood, there is some evidence that suggests involvement of reactive oxygen species (ROS). In parallel, protective effects of various antioxidants have been demonstrated by many research groups. Extensive studies of CsA-induced nephrotoxcity have confirmed that the antioxidants can restore the damaged function and structure of kidney. Subsequently, there have appeared numerous reports to demonstrate the positive antioxidant effects on liver and other organ damages by CsA. It may be timely to review the ideas to envisage the relationship between ROS and the CsA-induced toxicity. This review is comprised of a brief description of the immunosuppressive action and the secondary effects of CsA, and a synopsis of reports regarding the antioxidant treatments against the ROS-linked CsA toxicity. A plethora of recent reports suggest that antioxidants can help reduce many CsA's adverse effects and therefore might help develop more effective CsA treatment regimens.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.2
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• pp.126-136
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• 2010

Objectives The purpose of this study was to investigate the antiallergic and antioxidative effects of Chaenomeles Sinensis (CS). Methods CS pretreatments inhibited anti-DNP IgE in RBL-2H3 mast cells for an hour. we measured cell viability, $\beta$-hexosaminidase release, IL-4, TNF-$\alpha$ secretion, and IL-4, TNF-$\alpha$ mRNA expression CS pretreatments inhibited DNP-HSA($10\;{\mu}g/ml$) for ten minutes, we measured Dicholrodihydrofluorescein(DCF) and DPPH radical-scavenging activity in 0.5 mM 1,1-diphenyl-2-picrydrazyl(DPPH) radical solution, 0.1ml, 99% ethanol 0.8ml, and CS 0.1 ml mixed solution. Results 0, 1, 2, 3, 4, 5 mg/ml CS treatments were not affect on cell viability and inhibited b-hexosaminidase release, IL-4, TNF-$\alpha$ secretion, CS treatments also decreased IL-4, TNF-$\alpha$ mRNA expression in RBL-2H3 cells. CS treatments inhibited reactive oxygen species(ROS) and DPPH radical-scavenging activity. Conclusions These results suggest that CS may be useful for the prevention or treatment of allergic disease.