• Journal of the Korean Society of Radiology
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• v.15 no.7
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• pp.943-948
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• 2021

The purpose of this study was to investigate changes in surface dose due to increased scattering of gamma rays from patients injected with ^99mTc and ¹⁸F, which are radioactive isotopes, in close contact with materials with high atomic number such as the walls of the stable room. Prepare ^99mTc and ¹⁸F by injecting 20 and 10 mCi respectively into the NEMA phantom, and then measuring the surface dose for 60 minutes by positioning the phantom at a height of 1 m above the surface, at a distance of 0, 5 and 10 cm from the wall, and at the same location as the phantom facing the wall. Each experiment was repeated five times for reproducibility of the experiment and one way analysis of variability (ANOVA) was performed for significance testing and Tukey was used as a post-test. The study found that surface doses of 220.268, 287.121, 243.957, and 226.272 mGy were measured at ^99mTc, respectively, in the case of empty space and in the case of 0, 5 and 10 cm, while those of ¹⁸F were measured at 637.111, 724.469, 657.107, and 640.365 mGy, respectively. In order to reduce changes in surface dose depending on the patient's location while waiting, it is necessary to keep the distance from the ground or the wall where the patient is closely adhered to, or install an air mattress, etc., to prevent the scattered lines as much as possible, considering the scattered lines due to the wall etc. in future setup of the patient waiting room and safety room, and in addition to the examination, the external skin width may be reduced.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.237-246
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• 2016

This study is therefore aimed at measuring the surface dose rate and the spatial dose rate in and outside the radionuclide facility in order to ensure safety of the patients, radiation workers and family care-givers in their use of such equipment and to provide a basic framework for further research on radiation protection. The study was conducted at 4 restrooms in and outside the radionuclide facility of a general hospital in Incheon between May 1 and July 31, 2014. During the study period, the spatial contamination dose rate and the surface contamination dose rate before and after radiation use were measured at the 4 places-thyroid therapy room, PET center, gamma camera room, and outpatient department. According to the restroom use survey by hospitals, restrooms in the radionuclide facility were used not only by patients but also by family care-givers and some of radiation workers. The highest cumulative spatial radiation dose rate was 8.86 mSv/hr at camera room restroom, followed by 7.31 mSv/hr at radioactive iodine therapy room restroom, 2.29 mSv/hr at PET center restroom, and 0.26 mSv/hr at outpatient department restroom, respectively. The surface radiation dose rate measured before and after radiation use was the highest at toilets, which are in direct contact with patient's excretion, followed by the center and the entrance of restrooms. Unsealed radioactive sources used in nuclear medicine are relatively safe due to short half lives and low energy. A patient who received those radioactive sources, however, may become a mobile radioactive source and contaminate areas the patient contacts-camera room, sedation room, and restroom-through secretion and excretion. Therefore, patients administered radionuclides should be advised to drink sufficient amounts of water to efficiently minimize radiation exposure to others by reducing the biological half-life, and members of the public-family care-givers, pregnant women, and children-be as far away from the patients until the dose remains below the permitted dose limit.

• Progress in Medical Physics
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• v.11 no.2
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• pp.117-122
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• 2000

The IP(imaging plate) has been widely used to measure the two-dimensional distribution of incident radiation since it has a high sensitivity, reusability, a wide dynamic range, a high position resolution. Particularly, the easiness of acquiring digitized image using IP poses a strong merit because recent trend of data handling prefers image digitization. In order to test its usefulness in photon beam dosimetry, we measured the off-axis ratio(OAR) on portal planes and percent depth dose(PDD) within a phantom using IP, and compared the results with the data based on EGS4 Monte Carlo particle transport code, ion-chambers, conventional films. For the measurement, we used 6 MV X-rays, various field sizes. As a result, IP showed significant deviation from ion-chamber measurement: a significant overresponse, 100% greater than that of ion-chamber measurement at deep part of the phantom. Filtration of low-energy scattered photons at deep part of the phantom using 0.5 mm thick lead sheets did improve the result, only to the unacceptable extent. However, portal dose measurement showed possibilities of If as a dosimeter by showing errors less than 5%, as compared with film measurement.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.05a
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• pp.423-427
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• 2006

1) 바실러스는 불리한 환경조건에서 포자를 형성하며 포자는 균체가 죽어도 살아 남고, 외부 환경이 좋아지면 다시 발아하여 영양형 균체를 형성하게 된다. 본 연구에서 바실러스를 우점화와 포자의 활성화를 위해 열처리(80$^{\circ}C$, 10min)를 한다 울산분뇨처리장 슬러지 Cake를 배양하여 포자화 전 후 상태의 미생물의 EPS 추출결과 RCF법을 적용하였을 때 Carbohydrate물질이 다른 추출법에 비해 가장 많이 추출되었고, Steaming extraction법을 적용하였을 때 Protein이 가장 많이 추출되는 것으로 나타났으며, 포자화 전 보다 포자화 후의 EPS 양이 더 많이 추출될 것이라는 가설을 가지고 실험한 결과 포자화 전보다 포자화 후의 EPS 양이 더 많이 추출되었다. 울산분뇨처리장의 슬러지 Cake를 배양하여 포자화 전 후의 Cu의 제거정도를 비교한 결과 포자화 후의 EPS물질이 포자화 전의 EPS물질보다 Cu를 더 많이 제거하는 것으로 나타났으며 EPS 물질이 중금속 제거능력이 탁월하다고 할 수 있겠다. 2) 용인분뇨처리장과 천안하수처리장의 MLSS의 중금속 제거능력을 알아보기 위해 미생물량을 고려했을 경우와 미생물량을 고려하지 않은 경우로 나누어서 실험을 하였는데 울산분뇨처리장의 슬러지 Cake를 가지고 실험한 결과와 마찬가지로 Bacillus의 EPS물질이 중금속 제거에 탁월하다는 것을 알 수 있다. 3) Baillus를 사용하는 김천 식품폐수 처리장과 활성슬러지를 사용하는 천안하수처리장과의 EPS 함량을 비교한 결과 김천 식품폐수 처리장의 EPS 물질중 Protein과 Carbohydrate가 천안하수처리장의 활성슬러지보다 더 많은 것으로 나타났다.TEX>, DIN/DIP비 표층수 $23.91\pm3.42$, 저층수 $23.43\pm3.38$이었으며, 전반적으로 해역별 수질기준 I등급 내지는 II등급을 유지하고 있었고, 공간적으로는 외해측으로 갈수록 외해수와 혼합 확산되어 양호한 수질을 나타내었다. 장기적인 변동특성은 세그룹으로 구분되어진다.기 실험결과 용출용매로 증류수와 해수를 이용했을 때, 제강 슬래그에서 용출되는 납, 구리, 카드뮴, 수은의 용출 경향의 차이를 확인할 수 있었고 이에 따라서, 납, 구리, 카드뮴의 용출 유해성은 낮기 때문에 해양구조물로의 제강슬래그 유효이용은 적합할 것으로 판단되었다.im80%$로 계산되었다. 열형광선량계로 측정된 방사선량은 각각 1.8, 1.2, 0.8, 1.2, 0.8 (70 cm 거리) cGy로 측정되었으며, 환자의 복부 표면에서의 서베이메터를 이용한 측정량은 10.9 mR/h였다. 차폐구조물의 사용 시 전체 치료 동안에 태아선량은 약 1 cGy 정도로 평가되었다. 결론 : AAPM Report No.50의 자료에 따르면, 임산부의 방사선 치료 시 태아의 방사선 피폭선량은 5 cGy 이하일 경우에 방사선 피폭에 따른 태아의 위험이 거의 없는 것으로 제시되고 있다. 본원에서 차폐 구조물을 설치하였을 경우에 측정된 태아선량은 약 1 cGy로 측정되었고, 고안된 차폐구조물은 태아에 도달하는 방사선량을 감소시키기에 적합한 설계임이 입증되었다. 아니라 일반종합병원에서도 CTX-M형 ESBL 생성 E. coli와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필

• Korean Journal of Heritage: History & Science
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• v.50 no.3
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• pp.110-125
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• 2017

The purpose of this study is to investigate the constructional facts and the operational features of Hamchunwon(含春苑), a wonyu(苑?, a royal garden) constructed in Dongbu(Eastern District) of the capital city of Hanyang. As the living quarters of the queen dowagers were scheduled for relocation after the construction of Changgyeonggung Palace(昌慶宮) during the reign of King Seongjong(成宗), it is presumed that the screening tree planting project discussed around tongmangcheo(通望處, a place allowing open view) was the original form of Dongbu Hamchunwon. Dongbu Hamchunwon was a longitudinal royal garden built in the area across the section from Wolgeunmun Gate(月覲門) to Seoninmun Gate(宣仁門), which were both attached to the east side walls of Changgyeonggung Palace. The area corresponds to the west side area of the newly built main building of Seoul National University Hospital today. During the Joseon Dynasty, only royal gardens built within a palace were referred to as geumwon(禁苑, a palace garden). But Dongbu Hamchunwon which was built outside a palace was recognized as a symbolic and hierarchical space comparable to geumwon. The site location of Donbu Hamchunwon was an important place that corresponded to Naecheongnyong(內靑龍) according to Hanyang's geomancy, and large-scale public works were prohibited in order to protect the vein of Naecheongnyong. During the reign of King Injo(仁祖), part of Dongbu Hamchunwon was partitioned as a ranch. The area around the ranch was called Madongsan(馬東山) and Bangmawon(放馬苑) and was an open space used for rest and pleasure (amusement). In the early days of Hamchunwon's construction, fast growing trees were planted to screen the view to Changgyeonggung Palace. However, after the construction of Gyeongmogung Shrine(景慕宮), a broad scale tree planting project was undertaken to complement Naecheongnyong's vapor of the earth. In particular, after the construction of Yugeunmum Gate(?覲門) and Yucheommun Gate(?瞻門) during the reign of King Jeongjo(正祖), Dongbu Hamchunwon functioned as a key point on the King's progress for paying respects to the ancestors, which followed the route of Palace(Changgyeonggung)-Wonyu(Hamchunwon)-Ancestral Shrine(Gyeongmogung).