• Progress in Medical Physics
• /
• v.21 no.2
• /
• pp.232-237
• /
• 2010

The shielding materials designed for replacement of lead equivalent materials for lighter apron than that of lead in diagnostic photon beams. The absorption characteristics of elements were applied to investigate the lead free material for design the shielding materials through the 50 kVp to 110 kVp x-ray energy in interval of 20 kVp respectively. The idea focused to the effect of K-edge absorption of variable elements excluding the lead material for weight reduction. The designed shielding materials composited of Tin 34.1%, Antimon 33.8% and Iodine 26.8% and Polyisoprene 5.3% gram weight account for 84 percent of weight of lead equivalent of 0.5 mm thickness. The size of lead-free shielder was $200{\times}200{\times}1.5\;mm^3$ and $3.2\;g/cm^3$ of density which is equivalent to 0.42 mm of Pb. The lead equivalent of 0.5 mm thickness generally used for shielding apron of diagnostic X rays which is transmitted 0.1% for 50 kVp, 0.9% for 70 kVp and 3.2% for 90 kVp and 4.8% for 110 kVp in experimental measurements. The experiment of transmittance for lead-free shielder has showed 0.3% for 50 kVp, 0.6% for 70 kVp, 2.0% for 90 kVp and 4.2% for 110 kVp within ${\pm}0.1%$. respectively. Using the attenuation coefficient of experiments for 0.5 mm Pb equivalent of lead-free materials showed 0.1%. 0.3%, 1.0% and 2.4%, respectively. Furthermore, the transmittance of lead-free shielder for scatter rays has showed the 2.4% in operation energy of 50 kVp and 5.9% in energy of 110 kVp against 2.4% and 5.1% for standard lead thickness within ${\pm}0.2%$ discrepancy, respectively. In this experiment shows the designed lead-free shielder is very effective for reduction the apron weight in diagnostic radiation fields.

• Journal of radiological science and technology
• /
• v.35 no.4
• /
• pp.335-343
• /
• 2012

Intensity-modulated radiotherapy(IMRT) have the ability to provide better dose conformity and sparing of critical normal tissues than three-dimensional radiotherapy(3DCRT). Especially, with the benefit of health insurance in 2011, its use now increasingly in many modern radiotherapy departments. Also the use of linear accelerator with high-energy photon beams over 10 MV is increasing. As is well known, these linacs have the capacity to produce photonueutrons due to photonuclear reactions in materials with a large atomic number such as the target, flattening filters, collimators, and multi-leaf collimators(MLC). MLC-based IMRT treatments increase the monitor units and the probability of production of photoneutrons from photon-induced nuclear reactions. The purpose of this study is to quantitatively evaluate the dose of photoneutrons produced from 3DCRT and IMRT technique for Rando phantom in cervical cancer. We performed the treatment plans with 3DCRT and IMRT technique using Rando phantom for treatment of cervical cancer. An Rando phantom placed on the couch in the supine position was irradiated using 15 MV photon beams. Optically stimulated luminescence dosimeters(OSLD) were attached to 4 different locations (abdomen, chest, head and neck, eyes) and from center of field size and measured 5 times each of locations. Measured neutron dose from IMRT technique increased by 9.0, 8.6, 8.8, and 14 times than 3DCRT technique for abdomen, chest, head and neck, and eyes, respectively. When using IMRT with 15 MV photonbeams, the photoneutrons contributed a significant portion on out-of-field. It is difficult to prevent high energy photon beams to produce the phtoneutrons due to physical properties, if necessary, It is difficult to prevent high energy photon beams to produce the phtoneutrons due to physical properties, if necessary, it is need to provide the additional safe shielding on a linear accelerator and should therefore reduce the out-of-field dose.

• Management & Information Systems Review
• /
• v.38 no.1
• /
• pp.23-41
• /
• 2019

Smart Factory is different from existing factory automation in that it aims to produce personalized products with minimum time and cost through ICT. However, previous researches, not from consumers but from product suppliers, have focused on technology trends and technology application methods. In order for Smart Factory to be successful, it must go beyond supplier-focus to meet the needs of consumers. In this study, we surveyed the purchase intention of the personalized product manufactured by smart factory. Influencing factors of purchase intention were drawn as consumers' need for uniqueness, innovativeness, need for touch, and privacy concern, based on previous research. As results of data analysis, it was confirmed that respondents were willing to purchase personalized products, and that consumers' need for uniqueness, innovativeness, and need for touch had a significant impact on purchase intention of personalized products. Our findings can be summarized as follows. First, Consumers' need for uniqueness was found to have positive effects(${\beta}=0.168$) on purchase intention of personalized products. The desire to differentiate themselves from others will be reflected in their personalized products. Therefore, consumers with a higher desire for uniqueness tend to be more willing to purchase personalized products. Second, consumer innovativeness was found to have positive effects(${\beta}=0.233$) on purchase intention of personalized products. Personalized shoes suggested in this study is a new type of personalized product that is manufactured by the latest information and communication technologies such as multi-function robots and 3D printing. Therefore, consumers seeking innovative new experiences are more willing to purchase personalized products. Third, need for touch was found to have positive effects(${\beta}=0.299$) on purchase intention of personalized products. In a smart factory environment, prosuming participation is given to consumers. If consumers participate in the product development process and reflect their requirements on the product, they are expected to increase their purchase intention by virtually satisfying the need for touch. Fourth, privacy concern was found to have no significantly related to purchase intention of personalized products. This is interpreted as a willingness to tolerate the risk of exposing personal information such as home address, telephone number, body size, and preference for consumers who feel highly useful in personalized products.

• (The)Study of the Eastern Classic
• /
• no.37
• /
• pp.93-126
• /
• 2009

This study is about a event, which happened on January of 1603 in Hamheung. It has covered from the beginning through the conclusion of the event. The event was ignited by a naturalized citizen, Guilsang's coming to the capital city without permission from the government. With this study I've wished to find the situations of specific management of naturalized citizens as well as popular attitudes towards them at the time. Concerning with the event of Guilsang, I could find more detailed situations from "Naturalization Registration". The reason why Guilsang came to Seoul was that he wanted to ask for living together with his son-in-law's family in Yang-Ju. Before his coming, Bie-Byun-Sa had sent a official letter to the governor of Hamkyung-Do so that he had had to move somewhere between Anbyun and Yung-heung. But Guilsang had wanted to live with his whole family in Seoul. The place he visited first was Sa-Yuk-Won. He presented his petition through Yeozin language translator there. Sa-Yuk-Won then informed Ye-Jo to have him investigated. After its investigation, Ye-Jo reported to the king. There were arguments about Guilsang family in the government. Guilsang had wanted to live with his whole family, including his relatives and son-in-law. Guilsang's request had more pros than cons in terms of humanism. But letting him live in Seoul was a difficult decision for the government. but his family strenuously insisted on living in Seoul, trying to kill itself. Finally Government selected Yong-In which was a compromise between the naturalized citizens' wish and difficult position of Government. Yong-In Miejo-Hyun was a poor region where naturalized citizens had lived before but now empty after the wars. In the process of the event of Guilsang, Government differentiated naturalized citizens from general citizens and regarded them foreign. A man from Yeozin was naturalized due to economic reason. But, he couldn't accept to live somewhere except Seoul, separating from his family. Government concerned with dangers of naturalized citizen becoming into foreign agents and stabilization of borders. These concerns caused the policy of residential control and decentralization of naturalized citizens failed.

• (The)Study of the Eastern Classic
• /
• no.55
• /
• pp.265-291
• /
• 2014

Cheongeumrok is the journal of Gwonwoo(卷宇) Hong Chan-yu(1915-2005) during the period of January 9, 1969~January 14, 1982. He was personally involved in the foundation of a corporation called Yudohoi and also all of its operation, which makes him the most knowledgeable person about its history. His Cheongeumrok thus seems worthy enough as a proper material to arrange its history. Cheongeumrok consists of total 19 books, amounting to approximately 3,300 pieces of squared manuscript paper containing 200 letters per piece. He wrote it in Chinese and sometimes followed the Hangul-style word order while writing in Chinese. Many parts of the manuscript were written in a cursive hand with many Chinese poems embedded throughout it. The manuscript offers major information related to the corporation Yudohoi extracted from his journal. 1. There was a meeting of promoters to commemorate the foundation of the corporation in November, 1968, and it was in January, 1969 that it was established after getting a permit from the Ministry of Culture and Communication in January, 1969(Permit No. of Ministry of Culture and Communication: Da(다)-2-3(Jongmu(宗務)1732.5)). 2. Its office was moved from the original location of the 3rd floor of Wonnam Building, 133-1 Wonnam-dong, Jongro-gu, Seoul(currently Daekhak Pharmacy in front of Seoul National University Hospital) to Room 388 of Gwangjang Company, 4 Yeji-dong, Jongro-gu(office of Heungsan Social Gathering) and to second floor of KyungBo building, 21 Kyansu-dong, and to 3rd floor of Geongguk Building in Gyeongwoon-dong. 3. Its operational costs were covered by the supports of Seong Sang-yeong, the eldest son of Seong Jong-ho, the chairman of the board, later Kim Won-tae and Gwon Tae-hun, next chairmen of the board, and Hong Chan-yun, a director, since 1979. 4. His Confucian activities include participating in Seonggyungwan Seokjeonje (成均館 釋奠), joining in the erection of the Parijangseo(巴里長書) Monument and the publication of its commemorative poetry book, compiling the biographies(not completed) of Confucian patriotic martyrs for independence, and participating in the establishment of family rituals and regulations as a practice member. 5. His Yudohoi had a dispute with Seonggyungwan and lost a suit at the High Court in July, 1975 and Supreme Court in February, 1976. 6. There were discussions about its unification with Seonggyungwan Yudohoi, but there was hardly any progress. 7. Yudohoi started to provide full-scale courses on Confucian and Chinese classics under the leadership of Director Hong Chan-yu in 1979, and they have continued on today. Its courses for scholarship students including those for common citizens boast a history of 29 years and 220 graduates.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.1
• /
• pp.51-56
• /
• 2009

Purpose: Recently, most hospitals are introducing the PACS system and use of the system continues to expand. But small-scaled PACS called MicroPACS has already been in use through open source programs. The aim of this study is to prove utility of operating a MicroPACS, as a substitute back-up device for conventional storage media like CDs and DVDs, in addition to the full-PACS already in use. This study contains the way of setting up a MicroPACS with open source programs and assessment of its storage capability, stability, compatibility and performance of operations such as "retrieve", "query". Materials and Methods: 1. To start with, we searched open source software to correspond with the following standards to establish MicroPACS, (1) It must be available in Windows Operating System. (2) It must be free ware. (3) It must be compatible with PET/CT scanner. (4) It must be easy to use. (5) It must not be limited of storage capacity. (6) It must have DICOM supporting. 2. (1) To evaluate availability of data storage, we compared the time spent to back up data in the open source software with the optical discs (CDs and DVD-RAMs), and we also compared the time needed to retrieve data with the system and with optical discs respectively. (2) To estimate work efficiency, we measured the time spent to find data in CDs, DVD-RAMs and MicroPACS. 7 technologists participated in this study. 3. In order to evaluate stability of the software, we examined whether there is a data loss during the system is maintained for a year. Comparison object; How many errors occurred in randomly selected data of 500 CDs. Result: 1. We chose the Conquest DICOM Server among 11 open source software used MySQL as a database management system. 2. (1) Comparison of back up and retrieval time (min) showed the result of the following: DVD-RAM (5.13,2.26)/Conquest DICOM Server (1.49,1.19) by GE DSTE (p<0.001), CD (6.12,3.61)/Conquest (0.82,2.23) by GE DLS (p<0.001), CD (5.88,3.25)/Conquest (1.05,2.06) by SIEMENS. (2) The wasted time (sec) to find some data is as follows: CD ($156{\pm}46$), DVD-RAM ($115{\pm}21$) and Conquest DICOM Server ($13{\pm}6$). 3. There was no data loss (0%) for a year and it was stored 12741 PET/CT studies in 1.81 TB memory. In case of CDs, On the other hand, 14 errors among 500 CDs (2.8%) is generated. Conclusions: We found that MicroPACS could be set up with the open source software and its performance was excellent. The system built with open source proved more efficient and more robust than back-up process using CDs or DVD-RAMs. We believe that the operation of the MicroPACS would be effective data storage device as long as its operators develop and systematize it.