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A study on the xylographica of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ ("의방류취(醫方類聚)"에 대한 판본(版本) 연구)

  • Shin, Soon-Shik;Choi, Hwan-Soo
    • Korean Journal of Oriental Medicine
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    • v.3 no.1
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    • pp.1-15
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    • 1997
  • ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$(1445) is a book compiled the medical achievements of China and Choseon in those times and it's our source of pride to have it In this country. It also deserves careful investigation since this book can provide some clues of features of missing books in China and Korea. The extent of accuracy of xylographica of old books determines the possiblity of in depth further study. So authors attempted to investigate the xylographica of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ one of the 3 main books in Korea. Previous investigation done by Miki Sakae and Kim Doo Jong are noticeable. On the basis of their respective works, we analyzed 'Annals of the Choseon Dynasty' to find records related with ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ and estimated the situation of its publication. We tried figure the situation of those times of China, Japan and Korea(including North Korea) and tried to estimate the book's original xylographica as much as we could. By King Sejong's command, the first draft of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisted of 365 books was made by collaboration of civil officials and medical officers during the period from 1443 to 1445. And then from 1451(first year of Moonjong's reign) to 1464(l0th year of Sejo's reign) lots of manpowers were employed and through the process of countless erasure, proofreading, arrangement and rearrangement revised version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which is called by Sejo text was completed. After 3 years of wood engraving work, the first printed form of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ (alternately called Seongjong text) in folding case consisted of 266 chapters, 264 volumes came into the world in 1477.(8th year of Seongjong's reign). This was 32 years after the initial completion of the edition. So ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ exists in three forms as Sejong text, Sejo text and Seongjong text respectively. Since those texts were plundered during the Japanese invasion of Korea in 1592, none of the original copy remains within korea. The texts were constantly moved to kadeungcheongieong, to Kongdeungpyeongio, Jesookoan of Edo, to East University of department of classic books, to Cheoncho archives, to the Imperial Museum and finally is kept in the royal palace at present. (Doseoryo text Eulhae printing type) Reduced-size republication books of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ in wooden type were imported at the time of 'Byeongja Korea-Japan Treaty in 1876' and of those 2 books, one copy was treasured in the Royal Household of the Yi Dynasty and than was lost during the Korean War circa 1950. The other remaining copy has been kept succesively by Kojong's imperial grant, Royal doctor Hong Cheol Bo, Hong Taek Joo, Hong Ik Pyo the book agent, and now is kept In Yonsei University Library and this is the only existing copy in Korea at present. In 1965, Dongyang Medical college published the transcription version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisting of 11 books and then in 1981 after edition and arrangement by Choonghoa(中華) publishing company, photoprint copy of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ was published in Keumgang(金剛) publishing company In 1991, October Yeokang(驛江) publishing company producd photocopies of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which were previously translated into Korean by North Korea Institute of Oriental Medicine and then issued by medical publishing company. In China, two institutes, Zhejiang Institute of Traditional Chinese Medicine and Huzhou Traditional Chinese Medical Hospital cooperated to publish a revised and marked text consiting of 11 books by adding marking points to japanse Edohakhoondang text which were used as a reference. Both the korean and chinese texts issued were grounded by the ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ kept in the royal palace. Any further study concerning ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ can acquire its accuracy and objectivity when the japanese text kept in the royal palace is taken as an original copy.

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Stress dissipation characteristics of four implant thread designs evaluated by 3D finite element modeling (4종 임플란트 나사산 디자인의 응력분산 특성에 대한 3차원 유한요소해석 연구)

  • Nam, Ok-Hyun;Yu, Won-Jae;Kyung, Hee-Moon
    • The Journal of Korean Academy of Prosthodontics
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    • v.53 no.2
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    • pp.120-127
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    • 2015
  • Purpose: The aim was to investigate the effect of implant thread designs on the stress dissipation of the implant. Materials and methods: The threads evaluated in this study included the V-shaped, buttress, reverse buttress, and square-shaped threads, which were of the same size (depth). Building four different implant/bone complexes each consisting of an implant with one of the 4 different threads on its cylindrical body ($4.1mm{\times}10mm$), a force of 100 N was applied onto the top of implant abutment at $30^{\circ}$ with the implant axis. In order to simulate different osseointegration stages at the implant/bone interfaces, a nonlinear contact condition was used to simulate immature osseointegration and a bonding condition for mature osseointegration states. Results: Stress distribution pattern around the implant differed depending on the osseointegration states. Stress levels as well as the differences in the stress between the analysis models (with different threads) were higher in the case of the immature osseointegration state. Both the stress levels and the differences between analysis models became lower at the completely osseointegrated state. Stress dissipation characteristics of the V-shape thread was in the middle of the four threads in both the immature and mature states of osseointegration. These results indicated that implant thread design may have biomechanical impact on the implant bed bone until the osseointegration process has been finished. Conclusion: The stress dissipation characteristics of V-shape thread was in the middle of the four threads in both the immature and mature states of osseointegration.

The Adoption and Diffusion of Semantic Web Technology Innovation: Qualitative Research Approach (시맨틱 웹 기술혁신의 채택과 확산: 질적연구접근법)

  • Joo, Jae-Hun
    • Asia pacific journal of information systems
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    • v.19 no.1
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    • pp.33-62
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    • 2009
  • Internet computing is a disruptive IT innovation. Semantic Web can be considered as an IT innovation because the Semantic Web technology possesses the potential to reduce information overload and enable semantic integration, using capabilities such as semantics and machine-processability. How should organizations adopt the Semantic Web? What factors affect the adoption and diffusion of Semantic Web innovation? Most studies on adoption and diffusion of innovation use empirical analysis as a quantitative research methodology in the post-implementation stage. There is criticism that the positivist requiring theoretical rigor can sacrifice relevance to practice. Rapid advances in technology require studies relevant to practice. In particular, it is realistically impossible to conduct quantitative approach for factors affecting adoption of the Semantic Web because the Semantic Web is in its infancy. However, in an early stage of introduction of the Semantic Web, it is necessary to give a model and some guidelines and for adoption and diffusion of the technology innovation to practitioners and researchers. Thus, the purpose of this study is to present a model of adoption and diffusion of the Semantic Web and to offer propositions as guidelines for successful adoption through a qualitative research method including multiple case studies and in-depth interviews. The researcher conducted interviews with 15 people based on face-to face and 2 interviews by telephone and e-mail to collect data to saturate the categories. Nine interviews including 2 telephone interviews were from nine user organizations adopting the technology innovation and the others were from three supply organizations. Semi-structured interviews were used to collect data. The interviews were recorded on digital voice recorder memory and subsequently transcribed verbatim. 196 pages of transcripts were obtained from about 12 hours interviews. Triangulation of evidence was achieved by examining each organization website and various documents, such as brochures and white papers. The researcher read the transcripts several times and underlined core words, phrases, or sentences. Then, data analysis used the procedure of open coding, in which the researcher forms initial categories of information about the phenomenon being studied by segmenting information. QSR NVivo version 8.0 was used to categorize sentences including similar concepts. 47 categories derived from interview data were grouped into 21 categories from which six factors were named. Five factors affecting adoption of the Semantic Web were identified. The first factor is demand pull including requirements for improving search and integration services of the existing systems and for creating new services. Second, environmental conduciveness, reference models, uncertainty, technology maturity, potential business value, government sponsorship programs, promising prospects for technology demand, complexity and trialability affect the adoption of the Semantic Web from the perspective of technology push. Third, absorptive capacity is an important role of the adoption. Fourth, suppler's competence includes communication with and training for users, and absorptive capacity of supply organization. Fifth, over-expectance which results in the gap between user's expectation level and perceived benefits has a negative impact on the adoption of the Semantic Web. Finally, the factor including critical mass of ontology, budget. visible effects is identified as a determinant affecting routinization and infusion. The researcher suggested a model of adoption and diffusion of the Semantic Web, representing relationships between six factors and adoption/diffusion as dependent variables. Six propositions are derived from the adoption/diffusion model to offer some guidelines to practitioners and a research model to further studies. Proposition 1 : Demand pull has an influence on the adoption of the Semantic Web. Proposition 1-1 : The stronger the degree of requirements for improving existing services, the more successfully the Semantic Web is adopted. Proposition 1-2 : The stronger the degree of requirements for new services, the more successfully the Semantic Web is adopted. Proposition 2 : Technology push has an influence on the adoption of the Semantic Web. Proposition 2-1 : From the perceptive of user organizations, the technology push forces such as environmental conduciveness, reference models, potential business value, and government sponsorship programs have a positive impact on the adoption of the Semantic Web while uncertainty and lower technology maturity have a negative impact on its adoption. Proposition 2-2 : From the perceptive of suppliers, the technology push forces such as environmental conduciveness, reference models, potential business value, government sponsorship programs, and promising prospects for technology demand have a positive impact on the adoption of the Semantic Web while uncertainty, lower technology maturity, complexity and lower trialability have a negative impact on its adoption. Proposition 3 : The absorptive capacities such as organizational formal support systems, officer's or manager's competency analyzing technology characteristics, their passion or willingness, and top management support are positively associated with successful adoption of the Semantic Web innovation from the perceptive of user organizations. Proposition 4 : Supplier's competence has a positive impact on the absorptive capacities of user organizations and technology push forces. Proposition 5 : The greater the gap of expectation between users and suppliers, the later the Semantic Web is adopted. Proposition 6 : The post-adoption activities such as budget allocation, reaching critical mass, and sharing ontology to offer sustainable services are positively associated with successful routinization and infusion of the Semantic Web innovation from the perceptive of user organizations.

Real-Time Scheduling Scheme based on Reinforcement Learning Considering Minimizing Setup Cost (작업 준비비용 최소화를 고려한 강화학습 기반의 실시간 일정계획 수립기법)

  • Yoo, Woosik;Kim, Sungjae;Kim, Kwanho
    • The Journal of Society for e-Business Studies
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    • v.25 no.2
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    • pp.15-27
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    • 2020
  • This study starts with the idea that the process of creating a Gantt Chart for schedule planning is similar to Tetris game with only a straight line. In Tetris games, the X axis is M machines and the Y axis is time. It is assumed that all types of orders can be worked without separation in all machines, but if the types of orders are different, setup cost will be incurred without delay. In this study, the game described above was named Gantris and the game environment was implemented. The AI-scheduling table through in-depth reinforcement learning compares the real-time scheduling table with the human-made game schedule. In the comparative study, the learning environment was studied in single order list learning environment and random order list learning environment. The two systems to be compared in this study are four machines (Machine)-two types of system (4M2T) and ten machines-six types of system (10M6T). As a performance indicator of the generated schedule, a weighted sum of setup cost, makespan and idle time in processing 100 orders were scheduled. As a result of the comparative study, in 4M2T system, regardless of the learning environment, the learned system generated schedule plan with better performance index than the experimenter. In the case of 10M6T system, the AI system generated a schedule of better performance indicators than the experimenter in a single learning environment, but showed a bad performance index than the experimenter in random learning environment. However, in comparing the number of job changes, the learning system showed better results than those of the 4M2T and 10M6T, showing excellent scheduling performance.

A Study on the distinctive quality of the Younsijo(연시조) - The works of the 16th century - (연시조 성격의 대비적 고찰 - 16세기 작품을 대상으로 -)

  • Kim Sang-Jean
    • Sijohaknonchong
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    • v.22
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    • pp.195-223
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    • 2005
  • The Younsijo is a stream of Korean poem. not simply an aggregate of stanzas, but an organic structure. Younsijo was an appeared in the 16th century. The 16th century was focused on the literature of Sadaebu (noble family, 사대부). And the make an appearance is Danhyungsijo (simply-sijo, 단형시조), Yonsijo and Kasa(가사). In that case, a social stratum is why does singing each other form. The 16th century set metaphysics(성리학) as the national ideology. Metaphysics became most prevalent at the end of the 16th century. Yonsijo also appreared during the 16th century and was closeiy related to the idea of metaphysics. Both Younsijo and metaphysics were formulated by noble family, The Yonsijo was Formed in 16th century. And the 17th century was succession. The Yonsijo in 16th century is devide to Kanghosijo (강호시조) and Hunminsijo (훈민시조). Also, Kanghosijo is devide to Youkgaline Younsijo (육가계 연시조) and Sasigaline Yonsijo (사시가계 연시조). Hunminsijo used an expressive on the order of Oryoun(오륜). Therefore, this study is forced on , , and . These things, all of the end of the utility. This paper deals with Danhyungsijo and Kasa with main emphasis on works of Songgang(송강) Jungcheol(정철). The reason for dealing one writer's works is the discussion needs consistent standard. In analyzing Songgang's Danhyungsijo, Younsijoand and Kasa, one would discern the differences among three. As a result, one could conclude that both Danhyungsijo and Kasa mainly projects individual's emotional esthetic feeling, particularly, Danhyungsijo for emotional implication, and for in-depth emotional revealing. Younsijo were chosen as it supplements the shortcoming of Sijo(as it consists of three-line only) to effectively contain the ideas of metaphysics.

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Interpretation of the Umbrella Clause in Investment Treaties (국제투자조약상 포괄적 보호조항(Umbrella Clauses)의 해석에 관한 연구)

  • Jo, Hee-Moon
    • Journal of Arbitration Studies
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    • v.19 no.2
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    • pp.95-126
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    • 2009
  • One of the controversial issues in investor-state investment arbitration is the interpretation of "umbrella clause" that is found in most BIT and FTAs. This treaty clause requires on Contracting State of treaty to observe all investment obligations entered into with foreign investors from the other Contracting State. This clause did not receive in-depth attention until SGS v. Pakistan and SGS v. Philippines cases produced starkly different conclusions on the relations about treaty-based jurisdiction and contract-based jurisdiction. More recent decisions by other arbitral tribunals continue to show different approaches in their interpretation of umbrella clauses. Following the SGS v. Philippines decision, some recent decisions understand that all contracts are covered by umbrella clause, for example, in Siemens A.G. v. Argentina, LG&E Energy Corp. v. Argentina, Sempra Energy Int'l v. Argentina and Enron Corp. V. Argentina. However, other recent decisions have found a different approach that only certain kinds of public contracts are covered by umbrella clauses, for example, in El Paso Energy Int'l Co. v. Argentina, Pan American Energy LLC v. Argentina and CMS Gas Transmission Co. v. Argentina. With relation to the exhaustion of domestic remedies, most of tribunals have the position that the contractual remedy should not affect the jurisdiction of BIT tribunal. Even some tribunals considered that there is no need to exhaust contract remedies before bringing BIT arbitration, provoking suspicion of the validity of sanctity of contract in front of treaty obligation. The decision of the Annulment Committee In CMS case in 2007 was an extraordinarily surprising one and poured oil on the debate. The Committee composed of the three respected international lawyers, Gilbert Guillaume and Nabil Elaraby, both from the ICJ, and professor James Crawford, the Rapportuer of the International Law Commission on the Draft Articles on the Responsibility of States for Internationally Wrongful Acts, observed that the arbitral tribunal made critical errors of law, however, noting that it has limited power to review and overturn the award. The position of the Committee was a direct attack on ICSID system showing as an internal recognition of ICSID itself that the current system of investor-state arbitration is problematic. States are coming to limit the scope of umbrella clauses. For example, the 2004 U.S. Model BIT detailed definition of the type of contracts for which breach of contract claims may be submitted to arbitration, to increase certainty and predictability. Latin American countries, in particular, Argentina, are feeling collectively victims of these pro-investor interpretations of the ICSID tribunals. In fact, BIT between developed and developing countries are negotiated to protect foreign investment from developing countries. This general characteristic of BIT reflects naturally on the provisions making them extremely protective for foreign investors. Naturally, developing countries seek to interpret restrictively BIT provisions, whereas developed countries try to interpret more expansively. As most of cases arising out of alleged violation of BIT are administered in the ICSID, a forum under the auspices of the World Bank, these Latin American countries have been raising the legitimacy deficit of the ICSID. The Argentine cases have been provoking many legal issues of international law, predicting crisis almost coming in actual investor-state arbitration system. Some Latin American countries, such as Bolivia, Venezuela, Ecuador, Argentina, already showed their dissatisfaction with the ICSID system considering withdrawing from it to minimize the eventual investor-state dispute. Thus the disagreement over umbrella clauses in their interpretation is becoming interpreted as an historical reflection on the continued tension between developing and developed countries on foreign investment. There is an academic and political discussion on the possible return of the Calvo Doctrine in Latin America. The paper will comment on these problems related to the interpretation of umbrella clause. The paper analyses ICSID cases involving principally Latin American countries to identify the critical legal issues arising between developing and developed countries. And the paper discusses alternatives in improving actual investor-State investment arbitration; inter alia, the introduction of an appellate system and treaty interpretation rules.

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The Analysis of a Cerrobend Compensator and a Electronic Compensator Designed by a Radiation Treatment Planning System (방사선치료계획장치로 설계된 Cerrobend 선량보상체와 전자 선량보상체의 제작 및 특성 분석)

  • Nah Byung-Sik;Chung Woong-Ki;Ahn Sung-Ja;Nam Taek-keun;Yoon Mi-Sun;Song Ju-Young
    • Progress in Medical Physics
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    • v.16 no.2
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    • pp.82-88
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    • 2005
  • In this study, the physical compensator made with the high density material, Cerrobend, and the electronic compensator realized by the movement of a dynamic multileaf collimator were analyzed in order to verify the properness of a design function in the commercial RTP (radiation treatment planning) system, Eclipse. The CT images of a phantom composed of the regions of five different thickness were acquired and the proper compensator which can make homogeneous dose distribution at the reference depth was designed in the RTP. The frame for the casting of Cerrobend compensator was made with a computerized automatic styrofoam cutting device and the Millennium MLC-120 was used for the electronic compensator. All the dose values and isodose distributions were measured with a radiographic EDR2 film. The deviation of a dose distribution was $\pm0.99 cGy\;and\;\pm1.82cGy$ in each case of a Cerrobend compensator and a electronic compensator compared with a $\pm13.93 cGy$ deviation in an open beam condition. Which showed the proper function of the designed compensators in the view point of a homogeneous dose distribution. When the absolute dose value was analyzed, the Cerrobend compensator showed a $+3.83\%$ error and the electronic compensator showed a $-4.37\%$ error in comparison with a dose value which was calculated in the RTP. These errors can be admtted as an reasonable results that approve the accuracy of the compensator design in the RTP considering the error in the process of the manufacturing of the Cerrobend compensator and the limitation of a film in the absolute dosimetry.

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Diagnosis and Monitoring of Chronic Myeloid Leukemia: Chiang Mai University Experience

  • Tantiworawit, Adisak;Kongjarern, Supanat;Rattarittamrong, Ekarat;Lekawanvijit, Suree;Bumroongkit, Kanokkan;Boonma, Nonglak;Rattanathammethee, Thanawat;Hantrakool, Sasinee;Chai-Adisaksopha, Chatree;Norasetthada, Lalita
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.2159-2164
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    • 2016
  • Background: A diagnosis of chronic myeloid leukemia (CML) is made on discovery of the presence of a Philadelphia (Ph) chromosome. The success of the treatment of this form of leukemia with tyrosine kinase inhibitor (TKI) is monitored by reduction of the Ph chromosome. Objective: To compare the role of conventional cytogenetic (CC) methods with a real time quantitative polymerase chain reaction (RQ-PCR) and fluorescence in situ hybridization (FISH) for diagnosis and treatment monitoring of CML patients. The secondary outcome was to analyze the treatment responses to TKI in CML patients. Materials and Methods: This was a retrospective study of CML patients who attended the Hematology clinic at Chiang Mai University Hospital from 2005-2010. Medical records were reviewed for demographic data, risk score, treatment response and the results of CC methods, FISH and RQ-PCR. Results: One hundred and twenty three cases were included in the study, 57.7% of whom were male with a mean age of 46.9 years. Most of the patients registered as intermediate to high risk on the Sokal score. At diagnosis, 121 patients were tested using the CC method and 118 (95.9%) were identified as positive. Five patients failed to be diagnosed by CC methods but were positive for BCR-ABL1 using the FISH method. Imatinib was the first-line treatment used in 120 patients (97.6%). In most patients (108 out of 122, 88.5%), a complete cytogenetic response (CCyR) was achieved after TKI therapy and in 86 patients (70.5%) CCyR was achieved long term by the CC method. Five out of the 35 analyzed patients in which CCyR was achieved by the CC method had a positive FISH result. Out of the 76 patients in which CCyR was achieved, RQ-PCR classified patients to only CCyR in 17 patients (22.4%) with a deeper major molecular response (MMR) in 4 patients (5.3%) and complete molecular response (CMR) in 55 patients (72.4%). In the case of initial therapy, CCyR was achieved in 95 patients (79.1%) who received imatinib and in both patients who received dasatinib (100%). For the second line treatment, nilotinib were used in 30 patients and in 19 of them (63.3%) CCyR was achieved. In half of the 6 patients (50%) who received dasatinib as second line or third line treatment CCyR was also achieved. Conclusions: CML patients had a good response to TKI treatment. FISH could be useful for diagnosis in cases where CC analysis failed to detect the Ph chromosome. RQ-PCR was helpful in detecting any residual disease and determining the depth of the treatment response at levels greater than the CC methods.

An analysis of horizontal deformation of a pile in soil using a beam-on-spring model for the prediction of the eigenfrequency of the offshore wind turbine (해상풍력터빈의 고유진동수 예측을 위한 지반에 인입된 파일의 탄성지지보 모델 기반 수평 거동 해석)

  • Ryue, Jungsoo;Baik, Kyungmin;Kim, Tae-Ryong
    • The Journal of the Acoustical Society of Korea
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    • v.35 no.4
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    • pp.261-271
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    • 2016
  • In the prediction of response of a pile in soil, numerical approaches such as a finite element method are generally applied due to complicate nonlinear behaviors of soils. However, the numerical methods based on the finite elements require heavy efforts in pile and soil modelling and also take long computing time. So their usage is limited especially in the early design stage in which principal dimensions and properties are not specified and tend to vary. On the contrary, theoretical approaches adopting linear approximations for soils are relatively simple and easy to model and take short computing time. Therefore, if they are validated to be reliable, they would be applicable in predicting responses of a pile in soil, particularly in early design stage. In case of wind turbines regarded in this study, it is required to assess their natural frequencies in early stages, and in this simulation the supporting pile inserted in soil could be replaced with a simplified elastic boundary condition at the bottom end of the wind turbine tower. To do this, analysis for a pile in soil is performed in this study to extract the spring constants at the top end of the pile. The pile in soil can be modelled as a beam on elastic spring by assuming that the soils deform within an elastic range. In this study, it is attempted to predict pile deformations and influence factors for lateral loads by means of the beam-on-spring model. As two example supporting structures for wind turbines, mono pile and suction pile models with different diameters are examined by evaluating their influence factors and validated by comparing them with those reported in literature. In addition, the deflection profiles along the depth and spring constants at the top end of the piles are compared to assess their supporting features.

Development of 2.5D Electron Dose Calculation Algorithm (2.5D 전자선 선량계산 알고리즘 개발)

  • 조병철;고영은;오도훈;배훈식
    • Progress in Medical Physics
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    • v.10 no.3
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    • pp.133-140
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    • 1999
  • In this paper, as a preliminary study for developing a full 3D electron dose calculation algorithm, We developed 2.5D electron dose calculation algorithm by extending 2D pencil-beam model to consider three dimensional geometry such as air-gap and obliquity appropriately. The dose calculation algorithm was implemented using the IDL5.2(Research Systems Inc., USA), For calculation of the Hogstrom's pencil-beam algorithm, the measured data of the central-axis depth-dose for 12 MeV(Siemens M6740) and the linear stopping power and the linear scattering power of water and air from ICRU report 35 was used. To evaluate the accuracy of the implemented program, we compared the calculated dose distribution with the film measurements in the three situations; the normal incident beam, the 45$^{\circ}$ oblique incident beam, and the beam incident on the pit-shaped phantom. As results, about 120 seconds had been required on the PC (Pentium III 450MHz) to calculate dose distribution of a single beam. It needs some optimizing methods to speed up the dose calculation. For the accuracy of dose calculation, in the case of the normal incident beam of the regular and irregular shaped field, at the rapid dose gradient region of penumbra, the errors were within $\pm$3 mm and the dose profiles were agreed within 5%. However, the discrepancy between the calculation and the measurement were about 10% for the oblique incident beam and the beam incident on the pit-shaped phantom. In conclusions, we expended 2D pencil-beam algorithm to take into account the three dimensional geometry of the patient. And also, as well as the dose calculation of irregular field, the irregular shaped body contour and the air-gap could be considered appropriately in the implemented program. In the near future, the more accurate algorithm will be implemented considering inhomogeneity correction using CT, and at that time, the program can be used as a tool for educational and research purpose. This study was supported by a grant (#HMP-98-G-1-016) of the HAN(Highly Advanced National) Project, Ministry of Health & Welfare, R.O.K.

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