• Journal of the Korean association of regional geographers
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• v.13 no.3
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• pp.301-320
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• 2007

In Korean academic societies, old maps has not yet been properly investigated in terms of their genealogy, classification, detailed place names, historical backgrounds and the other aspects. With publication of the bibliographies and papers on old maps reserved in museum and library, the scope of research enlarged gradually its scope from 1970s. In 1980s, with the development of theoretical geography, scientific analysis were applied to investigate the projection method of Daedongyeo-jido. The 1990s proved a prominent decade for researches. The photo-copies of old maps enabled researchers to investigate the in-depth comparative study. The more important thing is that old maps became to be powerful instrument in the research of historical geography, such as territorial disputes and marine name(東海). And county old maps compiled by region became to be regional-cultural contents of local areas. Important issues in old map research in Korean academic societies are about Cheonha-do which is unique old world map in Korea, grid-system projection in old county maps and the genealogy of Daedongyeo-jido(manuscript and block print edition). This study shows that bibliography of all old maps preserved in each library and museum should be standardized. This could enable the exchange of information of old maps between institutes. The more important thing is that conciliation of human, social and natural sciences should be applied in the research of old maps.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.397-404
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• 1991

The steady state and decay characteristics of primary fluorescenece of phytoplanktons including Cyanophyceae and Cryptophyceae were investigated in vivo. At 580-640 nm region, fluorescence emission spectra were obtained from all algae examined. The observed fluorescence emission maxima were similiar$(\pm3\;nm)$ except Synechocorcus sp. (SYN). Considered $\lambda_{max}$ of emission spectra of phycobiliproteins and the excitation spectra with $\lambda_{max}=540-560nm$, it seems to be originated from biliproteins. Fluorescence lifetimes $(\tau)$ and decay curves were compared with standard solution of candidate organic compounds, b-phycoerythrin. The $\tau$ values obtained for phytoplankton with $\lambda_{max}=580nm$ were different depending upon the species of algae. The observed $\tau$ values were ranged from 1.39 ns to 1.95 ns. These are considerably shorter than $\tau(3.23\;us)$ for standard solution of b-phycoerythrin. The reduction of $\tau$ for phycoerythrin in vivo seems to be originated from effective energy transfer system between Chl. a and phycobiliprotein in intact cell. There are subtantial differences in fluorsecence spectra and lifetimes at the class level. At the species level, differences seems to be much smaller. The result of experiment suggests that measurement of fluorescence lifetimes may be helpful in the rapid characterization of algae. Direct application will likely be found in combination with the measurement of other luminescence parameters.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.103-107
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• 2008

Purpose: This paper describes a electron field presence of magnetic field, intensity and shape surface dose variation to clinical application possibility. Materials and Methods: The using 6 MeV electron and $10{\times}10\;cm^2$ field size, 9 hole to shielding block make the by measure the film, when the magnetic field position inside and outside of the X-Omat film and parallel plate ionization chamber using the surface dose measured. Results: Present of 4 cm to the side at angle about 3 degree from beam center, use of ring type magnetic is 0.9% increase the surface dose, lens block located in the magnetic field the surface dose 1.58% increase, half magnetic field's position on the side of them at the field center of the 3.6% increase of the surface dose. Conclusion: Surface dose variation is with magnetic field about the mean electron beam of progress direction change, orbit region patient's is inconvenient without surface dose increase percentage case goodness will be used as a useful way.

• Journal of the Korean Society of Radiology
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• v.14 no.2
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• pp.169-178
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• 2020

The number of CT scans is increasing every year due to the improvement of the medical standards of the public, and thus the annual dose of medical radiation is also increasing. In this study, we evaluated the effective dose of the human body exposed to CT scans and estimated LAR. First, five region were selected from the CT diagnostic reference level guideline, and the effective dose of human body exposed to each examination was evaluated by clinical CT device. Second, the human organs and effective dose were calculated using the ALARA-CT program under the same conditions. Third, lifetime attributable risk (LAR) estimated by the effective dose exposed through the previous CT scan was estimated. As a result, the most effective dose was 21.18 mSv during the abdomen 4 phase scan, and the dose level was below DRL for all other tests except for the abdominal examination. As a result of evaluating effective dose using a dose calculation program under the same conditions, the results showed about 1.1 to 1.9 times higher results for each examination. In the case of organ dose, the closer the organ to the scan site, the higher the scattering ray. The lifetime attributable risk to CT radiation dose in adults was gradually decreased with age, and the results were somewhat different according to gender.

• Journal of the Korean Society of Radiology
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• v.12 no.2
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• pp.123-131
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• 2018

This study compared PENELOPE with measured values from low energy peak to high energy peak to reduce peak to compton ratio and continuum background spectrum using $^{60}Co$, $^{137}Cs$ and mixed volume source. In addition, the change in backscattering and compton edge efficiency was compared with that of PENELOPE through changes in the vicinity of low energy. The results from the mixed volume source are applied to the soil samples to determine how much the minimum detection limits of the soil samples are reduced in the suppression and unsuppressed mode. The compton suppression of the low energy region of $^{60}CO$ (1,173 keV) was considerable, and the Compton edge RF for the $^{137}Cs$ (661 keV) peak was 2.8. In particular, the $^{60}Co$ source emits coincidence gamma rays of 1,173.2 keV and 1,332.5 keV, so compton inhibition was reduced by approximately 21%. RF of compton edges of 1,173 keV and 1,332 keV emitted from a $^{60}Co$ source was 3.2 and 3.4, and the peak to compton edge ratio was improved to 8: 1. And Compared with Penelope, the uncertainty was well within 2%. In compton unsuppressed mode, MDA values of 661 keV, 1,173 keV and 1,332 keV were 0.535, 0.173 and 0.136 Bq/kg, respectively, but decreased in compton suppressed mode to 0.121, 0.00826 and 0.00728 Bq/kg. Thus, Compton suppressed could reduce the background radioactivity and the radioactivity contained in the detector itself.

• Journal of the Korean Society of Radiology
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• v.11 no.3
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• pp.123-129
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• 2017

Compton suppression apparatus using the Compton scattering response, by inhibiting part of the spectrum Compton continuum Compton continuum in the area of the peak analysis of the gamma rays that enables a clearer device. In order to find out the geometry structure of high-purity germanium detector(HPGe) -NaI(TI) and to optimize the effect of movement, Monte Carlo simulation was used to grasp the behavioral characteristics of Compton suppression and compare several layout structures. And applied to the cylinder beaker used for the environmental measurement by using the efficiency according to the distance. For the low-energy source such as 81 keV, the Compton continuum is scarcely developed and the suppression effect is also insignificant because the scattering cross-section of the Compton effect is relatively low. In the spectrum for the remaining energy, it can be seen that the Compton continuum part is suppressed in a certain energy range. Compton suppression effect was not significantly different from positional shift. average reduction factor(ARF) value was about 1.08 for 81 keV and about 1.23 for 1332.4keV energy at the highest value. It can be seen that suppression over the Compton continuum region of the energy spectrum is a more appropriate arrangement. Therefore, it can be applied to various environmental sample measurement through optimized structure.

• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.227-253
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• 1997

Twenty-first century will be in the era of culture and art as postmodernims progresses, therefore, geography which is is traditionally concerned with regional study needs to deeply study the culture of region. Regional symbols are clue to identify regional culture which is environments of symbolic space. Especially the study of urban culture come to the needs of times with occurring global city, urban symbols make clear urban culture and urban identity. The aim of this paper is to analyze urban symbols, that is urban songs, urban birds, urban trees, urban flowers to study urban culture in korean cities, urban symbols make clear urban spatial environment which is natural and human, and then, urban symbols make clear urban identity. The analytical results of lyrics of urban songs in the 76 cities of korea include names of mountain, river, sea and place, the names of mountain and river make clear urban identies which is natural and human characteristics, it is environment of symbolic space which brings unity, one body. Especially it is environment of symbolic space which comprise fung-soo(風水) aspects, place names well represent symbolic space. The analytical results of symbolic things, that is urban birds, urban trees, urban flowers in the 78 cities of korea indicate they are gain and gain established, they are also our environments of symbolic space which is curtual settlings of our life, but they are imported not native species but foreign species which have not environment of symbolic space. The results of this paper implicate urban symols should review. because urban symbols fit to our natural and human environments of symbolic space.

• Journal of the Korean association of regional geographers
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• v.9 no.3
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• pp.276-296
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• 2003

This study is to analyze the adoption of environmentally friendly fanning(EFF) by Actor-Network Theory(ANT). ANT declares that the world is full of hybrid entities containing both human and non-human elements and maintains that adoption of an innovation comes as a consequence of the action of everyone in the chain of actors who has anything to do with it. In this study, adoption of EFF will be analysed through the role of actors and networks. And this paper try to identify the intermediaries and obligatory passage point(OPP) in each networks. In study area, 5 actors, -nature, governmental institute, food processors, consumers and farmers-, have each roles in their networks, But only 18 farmers adopted EFF. This study revealed that three OPPs were not overcome in each network. The one is nature, such as water and soil pollution. Another is shortage of reliability between farmers and governmental institute. The other is shortage of information about agricultural commodity trade. And through this application of ANT to the EFF, we contend that ANT can be useful for studies of diffusion of EFF and sustainability of rural systems in situations where interactions of the social, technological and political are regarded as particularly important.

• The Journal of the Acoustical Society of Korea
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• v.39 no.5
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• pp.379-389
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• 2020

In this study, the flow and noise performances of high-speed fan motor unit for cordless vacuum cleaner is improved by optimizing the impeller which drives the suction air through flow passage of the cordless vacuum cleaner. Firstly, the unsteady incompressible Reynolds averaged Navier-Stokes (RANS) equations are solved to investigate the flow through the fan motor unit using the computational fluid dynamics techniques. Based on flow field results, the Ffowcs-Williams and Hawkings (FW-H) integral equation is used to predict flow noise radiated from the impeller. Predicted results are compared to the measured ones, which confirms the validity of the numerical method used. It is found that the strong vortex is formed around the mid-chord region of the main blades where the blade curvature change rapidly. Given that vortex acts as a loss for flow and a noise source for noise, impeller blade is redesigned to suppress the identified vortex. The response surface method using two factors is employed to determine the optimum inlet and outlet sweep angles for maximum flow rate and minimum noise. Further analysis of finally selected design confirms the improved flow and noise performance.

• Korean Journal of Acupuncture
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• v.30 no.1
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• pp.64-72
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• 2013

Objectives : The aim of this study was to investigate whether warm-needling is more effective than acupuncture in relieving the pain and improving the symptoms of knee osteoarthritis(OA). Methods : 76 volunteers with knee OA participated in the study. The subjects were randomly assigned to one of two groups. One group received warm-needling(n=38), while the other group received acupuncture(n=38). Sixteen sessions of warm-needling or acupuncture were conducted on the pain region of each problematic knee over a period of 8 weeks. The Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC) scores, physical health score based on the 36-Item Short-Form Health Survey(SF-36) and the Global Assessment(PGA) was measured. Results : Compared to the acupuncture group, the warm-needling group showed a significant decrease in pain, function, and total WOMAC scores according to the Mann-Whitney U-test. The PGA scores of the warm-needling group also showed a significant improvement compared to the acupuncture group. Conclusions : Warm-needling showed a greater pain relief effect on knee OA compared to the acupuncture group. These findings suggest that warm-needling may be a promising alternative therapy for treating knee OA.