• Journal of the Korean association of regional geographers
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• v.12 no.5
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• pp.571-582
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• 2006

This study look into a role change and geographical inertia of the central place. The place is selected and progressed as the center which is the joining of physical condition and social situation of the region. The central place is the role change according to social change but it has geographical inertia as the central place. The result is as follows. Firstly, the role of regional center is changed. This sample region is the center of a national defense and administration and traffic in Three-Country period. But the role of the national defense is disappeared with the unity of the three countries. A traffic center facility was lost because of traffic axis changed from the east-west line to the north-south line when Ko-Ryo period. A facility loss as a traffic center leads to diminish the administration function and the movement of the regional center within that area. Secondary. the new regional center function was maintained by the joining of an outside and inside peoples. It maintained the geographical inertia by Confucianism culture instead of administration function. Thirdly, it had geographical location movement within the area.

• Journal of Biomedical Engineering Research
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• v.28 no.1
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• pp.148-152
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• 2007

In this paper, we have synthesized $Gd_2O_3:Eu^{3+}$ nano phosphor particle using a low temperature solution-combustion method. We have investigated the structure and the luminescent characteristic as the sintering temperature and europium concentration. From XRD(X-ray diffraction) and SEM(scanning electron microscope) results, we have verified that the phosphor particle was fabricated a spherical shape with $30{\sim}40nm$ particle size. From the photoluminescence results, the strong peak exhibits at 611 um and the luminescent intensity depends on europium concentration. $Gd_2O_3:Eu$ fine phosphor particle has shown excellent luminescent efficiency at 5 wt% of europium concentration. The phosphors calcinated at $500^{\circ}C$ have possessed the x-ray peaks corresponding to the cubic phase of $Gd_2O_3$. As calcinations temperature increased to $700^{\circ}C$, the new monoclinic phase has identified except cubic patterns. From the luminescent decay time measurements, mean lifetimes were $2.3{\sim}2.6ms$ relatively higher than conventional bulk phosphors. These results indicate that $Gd_2O_3:Eu$ nano phosphor is possible for the operation at the low x-ray dose, therefore, the application as medical imaging detector.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.176-176
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• 2007

Flat-panel direct conversion detectors used in compound substance of semiconductor are being studied for digital x-ray imaging. Recently, such detectors are deposited by physical vapor deposition(PVD) generally. But, most of materials (HgI2, PbI2, TlBr, PbO) deposited by PVD have shown difficult fabrication and instability for large area x-ray imaging. Consequently, in this paper, we propose applicable potentialities for screen printing method that is coated on a substrate easily. It is compared to electrical properties among semiconductors such as $HgI_2$, $PbI_2$, PbO, HgBrI, InI, and $TlPbI_3$ under investigation for direct conversion detectors. Each film detector consists of an ~25 to $35\;{\mu}m$ thick layer of semiconductor and was coated onto the substrate. Substrates of $2cm{\times}2cm$ have been used to evaluate performance of semiconductor radiation detectors. Dark current, sensitivity and physics properties were measured. Leakage current of $HgI_2$ as low as $9pA/mm^2$ at the operation bias voltage of ${\sim}1V/{\mu}m$ was observed. Such a value is not better than PVD process, but it is easy to be fabricated in high quality for large area x-ray Imaging. Our future efforts will concentrate on optimization of growth of film thickness that is coated onto a-Si TFT array.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.29-29
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• 2007

TFT, LCD, OLED, PDP and FED를 비롯한 많은 디스플레이 장치가 개발, 연구되고 있으며, 이러한 디스플레이 장치에 대한 수 많은 application 연구 또한 진행되고 있다. TFT-LCD는 이미 방사선 검출기로서 연구가 오랜전에 연구되어 상용화가 되었으며, LCD는 XLV로서 적용을 위한 연구가 진행되고 있으며, 그 외 수 많은 디스플레이 장치에 대한 활발한 연구가 진행되고 있는 실정이다. PDP는 대면적, 낮은 제작 비용, 높은 contrast의 이점으로 디스플레이 장치로서 활발한 연구가 진행되고 있다. 본 논문에서는 PDP를 처음으로 방사선 검출기로 적용하기 위한 연구를 수행하였다. 제작된 7 인치 AC-PDP는 다양한 가스종류 및 압력을 가진 300um의 pixel pitch룰 가진 3 전극 구조로서, coplanar readout과 대항형 readout을 통해 신호량을 분석하였다. 결과 50-100Kvp의 진단 영역의 X-ray energy에서 줄은 민감도와 훌륭한 선형성을 보였으며, 가스 종류 및 압력, 신호 검출방식에 따라 각각 다른 특성을 보였다. 이는 PDP 내 X선과의 Interaction, R/O method. Material에 강하게 의존한다.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.726-731
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• 2010

Purpose: Autologous fat grafting is a popular procedure for the correction of the soft tissue depression and deformity. But there are several issues required to be carefully considered in relation to this procedure, mainly about the unpredictability and the low survival rate of the grafted fat due to absorption and partial necrosis. Sphingosine-1-phosphate (S1P) is a lysophospholipid mediator that has been proposed to promote angiogenesis and to regulate the differentiation of adipose derived stromal cells (ASCs). In this study, we analyzed the viability of the grafted fat tissue mixed with S1P into each 12 nude mice (cann.cg-fox1nu/crlori) compared to the group of mice grafted fat tissue only. Methods: Human aspirated fat was grafted subcutaneously into the backs of 8-week-old nude mice with or without S1P. Eight weeks later, the grafted fat was harvested and the weight and volume were checked. The fat was stained with hematoxylin-eosin and 4',6-diamidino-2-phenylindole. Results: S1P group weighed significantly more than the control group (p=0.009), and the volume from the S1P group was considerably larger than that of the control group (p=0.004) either. In histological features, the surviving layer of the S1P group was thicker than the control group and microvasculature appeared to be prominent in the S1P group, especially in the outer layers. Conclusion: These findings suggest that S1P plays a vital role in the soft tissue augmentation, potentially providing a novel point of the control in adipose tissue for microfat graft.

• Journal of Powder Materials
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• v.30 no.6
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• pp.516-520
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• 2023

Highly safe lithium-ion batteries (LIBs) are required for large-scale applications such as electrical vehicles and energy storage systems. A highly stable cathode is essential for the development of safe LIBs. LiFePO₄ is one of the most stable cathodes because of its stable structure and strong bonding between P and O. However, it has a lower energy density than lithium transition metal oxides. To investigate the high energy density of phosphate materials, vanadium phosphates were investigated. Vanadium enables multiple redox reactions as well as high redox potentials. LiVPO₄O has two redox reactions (V⁵⁺/V⁴⁺/V³⁺) but low electrochemical activity. In this study, LiVPO₄O is doped with fluorine to improve its electrochemical activity and increase its operational redox potential. With increasing fluorine content in LiVPO₄O_1-xF_x, the local vanadium structure changed as the vanadium oxidation state changed. In addition, the operating potential increased with increasing fluorine content. Thus, it was confirmed that fluorine doping leads to a strong inductive effect and high operating voltage, which helps improve the energy density of the cathode materials.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.170-181
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• 2011

This Research will explore the meaning indicated in the landscape meaning and feature of literary group culture, focusing in Gurujeong(九老亭: pavilion for nine elders) and Samgaeseokmun(三溪石門: stone gate in three valleys) located in Dundeok-myun, Imshil-gun, and will seek to understand the implications by studying the cultural landscape spread out in the area. The place where Gurojeong and Samgaeseokmun is located is the meeting point of the three valleys, Dunnam stream, Osu stream, and Yul stream, which is the main location to view the beautiful scenery, which has the nickname as the dwelling place of a celestial being. Especially, based on the description of old maps, "Samgae(three valleys)" and "Samgaeseokmun" possesses significance as a landmark and shows a characteristic feature of landscape structures of low hills. Dangugurohwe(丹丘九老會: nine elders gathering on the dwelling of a celestial being) originated from Hyangsangurohwe(香山九老會: gathering of nine elders on a fragrant mountain), where Baekgeoi(白居易) of China was one of the main people. This group was organized by nine elders over the age of 60 desiring to view the scenery of Doyeonmyeong. The group enhanced the literary spirit on the low hill, erecting a tower, and enjoying the beautiful scenery changing every season with scholars from the same region. This phenomenon seems to have been formed upon the positive response to gatherings of elders, which were prevalent in the Joseon Dynasty. If the internal idea pursued by the group was "longevity," the external idea pursued can be summarized as "the spirit the respect for the elders." Naming the groups as 'Dangudae(place where the celestial being lives), Guseondong(valley of seeking a celestial life), Bangjangsan(mountain of a high priest), and Daecheondae(place of communicating with God) was likely a device to introspect oneself and symbolize one's life process. Furthermore, the reason Samgaeseokmun, which is an imitation of Choi, Chiwon's work, was built near Soyocheo, was probably to yearn the celestial land and based on the desire to follow Choi, Chiwon, who was the most self-fulfilling being presumed to have become a celestial being by practicing the pursuit of freedom, escaping from the reality. After tracing the symbolizing meaning of the four letters carved in the left side of the stone wall of Dangudae, the conclusion that this place was not only a place for literary gatherings of the nine elders of Saseong(four families), but was a place where the celestial being dwelled could be inferred. Corresponding with Dangudae and Gurojeong, which are places where the order of human and nature is harmonized and where its meaning associated with the location intensifies, arouses strong bond, can be said to be the symbol of the traces of celestial beings where the spirits of attachment to a certain place is embedded. The acts performed in Dangugurohwe were those of traditional leisure including strolling, viewing the scenery, drinking, composing poems, and playing instruments, and sometimes listening to stories, tea ceremony, prayers, and fishing were added, which indicates that the gathering had a strong tendency towards pastoral and hermit life.

• Journal of the Daesoon Academy of Sciences
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• v.41
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• pp.1-25
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• 2022

This paper examines whether the dynamic and practical nature of Daoism has a significant relationship with the messianic figure Kang Jeungsan (姜甑山) via Honam (湖南) Daoism's Jinindaemangron (眞人待望論, discourse on awaiting an immortal). To this end, the historical implementation of Daoism's social transformation of consciousness in China and Korea is explored, and then the circumstances of Honam Daoism, in particular, are considered. Following that, analysis turns to the 'Jinindaemangron' in the late Joseon Dynasty that developed in Honam. As a result of the discussion, Daoism's social transformation of consciousness was expressed in China through the anti-establishment activities of the early Daoist groups such as Wudoumidao (五斗米道) and Taipingdao (太平道), movements that sought to build utopias. Throughout this process, the term, zhenren (眞人, 'jinin' in Korean), that originally meant 'master,' was transformed into the idea of a future savior. In the case of Korea, the dynamic and practical nature of Daoism can be found in the preface of Nanrang tombstone (鸞郎碑序) written by Choi Chi-won (崔致遠) which was later inherited by the Danhak sect (丹學派) practitioners who struggled against Buddhist monastics. Additionally, examined is the Docham theory of geomancy (圖讖說) that rose after Goryeo, the prophecy of 'Mokjadeuksul (木子得國說 a Lee clansman shall attain the kingdom)' that appeared thereafter, and the Prophecies of Jeong Gam (鄭鑑錄)'s 'Jinindaemangron' in the Joseon Dynasty. Next, the circumstances of Honam Daoism can be considered with regards ti Choi Chi-won and Doseon (道詵) in ancient times, and it can be confirmed that Nam Gung-du (南宮斗) and Kwon Geuk-jung (權克中) were entangled behind Kang Jeungsan. The close relationship among the Daoist Jeong family of Onyang (溫陽鄭氏), the Koh family of Jangheung (長興 高氏), and Kwon Geuk-jung was also confirmed in this study. Finally, in dealing with the 'Jinindaemangron' of Honam in the late Joseon Dynasty and the birth of Kang Jeungsan, Honam Daoism's intense consciousness of social transformation receives first focus, and this is expressed through Prophecies of Jeong Gam, and the religious ideologies of Donghak (東學) and Namhak (南學). These expressions are analyzed through Song of Gungeul (弓乙歌), composed by Jeongryeom (鄭磏), and through Daesoon Jinrihoe's The Canonical Scripture (典經). As a result, it can be confirmed that the messianic significance of the Kang Jeungsan's advent lay on the basis of the people's desire for an ideal future, which is a notion that had been ripening for several centuries.

• Journal of radiological science and technology
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• v.31 no.1
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• pp.83-87
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• 2008

The purpose of this study is to get the correction factor to correct the measured values of the absolute absorbed dose proportional to the water equivalent depth. The measurement conditions in white polystyrene and water phantoms for 10MV X-ray beam are that the distance of source to center of ionization chamber is fixed at SAD 100 cm, the field sizes are $10{\times}10\;cm^2$, $20{\times}20\;cm^2$ and the depths are 2.3 cm, 5 cm, 10 cm, and 15 cm, respectively. The mean value of ionization was obtained by three times measurements in each field size and depths after delivering 100 MU from linear accelerator with output of 400 MU per min to the two phantoms. The correction factor and the percentage deviation in TPR were obtained below 0.97% and 0.53%, respectively. Therefore, we can get high accuracy by using the correction factor and the percentage deviation in TPR in measuring the absolute absorbed dose with the solid water equivalent phantom.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.791-797
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• 2011

Purpose: Angiosarcoma is a rare and aggressive malignant soft tissue tumor. Due to a lack of the established optimal treatment modalities, however, an extensive resection followed by an early detection has been reported to be the best treatment of choice. We analyzed the clinical course of six patients, hence attempted to contribute to making a treatment plan for patients with angiosarcoma. Methods: Six patients who have been surgically treated between 2005 and 2010 are included. Through a retrospective analysis of the medical records, we evaluated the pattern of disease detection, a past history, time span between the detection and the primary surgery, surgical treatment modalities, time span between the primary surgery and the recurrence/metastasis, the sites of metastasis and the secondary treatment modalities. Results: The mean age of patients was 70.5 years; all male; and the sites were the scalp. Four patients underwent the reconstruction using a local flap with a skin graft and two patients using a free flap. The mean period elapsed until the primary operation since the identification was 7.3 months and until a recurrence or a metastasis occurred following the primary operation was 12 months. Four patients had pulmonary metastasis. As a secondary therapy, four patients underwent the radiotherapy and one was treated with the chemotherapy. At the present, five patients died and one undergoes a monitoring of the clinical course. Conclusion: It would be mandatory to shorten the length of hospital stay and to return patients to their daily lives as the earliest as possible using relatively simpler surgical methods, thus attempting to give them opportunity to resume their previous normal life.