• Journal of Radiation Protection and Research
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• v.23 no.3
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• pp.185-196
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• 1998

현재의 방사선방호 원칙과 체계는 국제방사선방호위원회 (ICRP)의 권고에 기반을 두고 있 다. ICRP 의 권고는 대부분 히로시마/나카사키 원폭피해 생존자들에 대한 역학조사 및 수명 연구결과 그리고 관련 방사선생물학 연구결과를 바탕으로 전세계 5개 인구집단(일본, 미국, 푸에리토리코, 영국과 중국)에 대한 방사선위험계수의 예측 및 평가결과에 근거를 두고 있다. 이 저선량 방사선의 (확률적 영향) 위험계수는 인체피폭 방사선량과 그 영향간에는 선형 비례관계가 있으며 영향유발의 문턱값이 존재하지 않는다는 가정인 '선형 무문턱값 선량-영향 모델 (Linear No-Threshold Dose-Effect Model, 이른바 LNT 모텔)' 을 도입하여 유도된 것이다(譯者 밑줄). 그러나 이 LNT 가정의 과학적 근거와 정당성에 대한 비난이 원자력산업계나 일부 과학자들에 의해 제기된 이래, 최근에는 미국 보건물리학회 (HPS)에서 'LNT 가정이 선량과 영향의 관계를 단순화하며 낮은 선량의 위험음 과대평가한다'는 성명서를 발표하기도 했다. 이후 이에 대한 논쟁이 다시 시작되어, 1997 년에 스페인의 Sevill에서는 IAEA와 WHO의 공동주최와 UNSCEAR의 협조로 '저준위 방사선 영향에 대한 국제회의'가 개최되기도 하였으나 아직 어느 쪽에도 유리한 결론이 단정적으로 나지 않았으며, 실질적인 대안이 없는 현실에서 이 LNT 가정은 여전히 방사선방호의 철학적 기초로 남아 있다(譯者 밑줄). 한편, 저선량 방사선의 영향에 대해서는 우리나라에서도 '방사선방어학회, ‘98 년 춘계 심포지움' 및 '원자력학회, '98 년 춘계 학술발표회 워크??????'에서 한양대학교의 이재기 교수에 의하여 소개, 논의된 바 있다.이 논문은 이러한 논의의 후속으로 역자중 일인이 위원으로 있는 OECD/NEA 방사선방호위원회 (CRPPH)가 최근에 ('98.7.) 발간한 보고서를 번역, 주해한 것으로, 과학지식의 진보에 따라 방사선방호분야에서 관심이 되는 주제들에 대한 위원회의 검토의견을 소개하고 있다. 따라서 이 논문이 국내의 방사선방호분야 관계자들에게 최신정보 습득과 지식함양에 좋은 도움이 되기를 기대한다.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.122.2-122.2
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• 2011

For more than a decade, NEA (Near-Earth Asteroid) survey teams equipped with 1 meter-class telescopes discovered thousands of NEAs in the northern sky. As of August 2011, some 8,200 NEAs have been cataloged, yet only five percent of them has been investigated for their physical and chemical properties. In order to improve current situation, we propose a deep ecliptic survey utilizing KMTNet, for detection and characterization of NEAs in the southern sky. Thanks to the wide-field capability (four square degrees) of the telescopes, we will be able to considerably expand the search volume carrying out precision photometry down to 21.5th magnitude. We plan to focus our survey on opposition and two "sweet spots" in the ecliptic belt. Since SDSS colors characterize mineralogical properties of NEAs, g', r', i', z' filters will be employed. Based on the round-the-clock observation, we will study their rotational properties; for multiple systems, mass, density and other physical parameters can be obtained. We plan to maintain a dedicated database of the physical and mineralogical properties of NEAs. With this archive, it is expected that our understanding on the population will see a drastic change. We also plan to participate in the GAIA Follow-Up Network for ground based observation of the Solar System Objects (GAIA-FUN-SSO). The follow- up astrometry will be performed upon alerts issued by the GAIA-FUN-SSO Central Node in France.

• Nuclear Engineering and Technology
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• v.42 no.5
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• pp.552-561
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• 2010

This study investigates the solubility of neptunium (Np) in the deep natural groundwater of the Korea Atomic Energy Research Institute Underground Research Tunnel (KURT). According to a Pourbaix diagram (pH-$E_h$ diagram) that was calculated using the geochemical modeling program PHREEQC 2.0, the redox potential and the carbonate ion concentration both control the solubility of neptunium. The carbonate effect becomes pronounced when the total carbonate concentration is higher than $1.5\;{\times}\;10^{-2}$ M at $E_h$ = -200 mV and the pH value is 10. Given the assumption that the solubility-limiting stable solid phase is $Np(OH)_4(am)$ under the reducing condition relevant to KURT, the soluble neptunium concentrations were in the range of $1\;{\times}\;10^{-9}$ M to $3\;{\times}\;10^{-9}$ M under natural groundwater conditions. However, the solubility of neptunium, which was calculated with the formation constants of neptunium complexes selected in an OECD-NEA TDB review, strongly deviates from the value measured in natural groundwater. Thus, it is highly recommended that a prediction of neptunium solubility is based on the formation constants of ternary Np(IV) hydroxo-carbonato complexes, even though the presence of those complexes is deficient in terms of the characterization of neptunium species. Based on a comparison of the measurements and calculations of geochemical modeling, the formation constants for the "upper limit" of the Np(IV) hydroxo-carbonato complexes, namely $Np(OH)_y(CO_3)_z^{4-y-2z}$, were appraised as follows: log $K^{\circ}_{122}\;=\;-3.0{\pm}0.5$ for $Np(OH)_2(CO_3)_2^{2-}$, log $K^{\circ}_{131}\;=\;-5.0{\pm}0.5$ for $Np(OH)_3(CO_3)^-$, and log $K^{\circ}_{141}\;=\;-6.0{\pm}0.5$ for $Np(OH)_4(CO_3)^{2-}$.

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.73-78
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• 2000

The Sit-and-Reach Test (SRT) is commonly nea to assess flexibility of the spine and length of the hamstring muscle, The purpose of this study was to describe hamstring muscle length as reflected by use of the SRT, the Hip Joint Angle (HJA) and Sack length(from C7 to S2) in children, to examine the correlation between Back length, SRT and HJA measurements and to examine gender differences. The 162 subjects were participated without known musculoskeletal and neurological impairments of their spine or lower exeremities. In the Long-silting position, the Back length, SRT and HJA measurements were obtained. A mean Back length value of 46.2cm, a mean SRT value of 29.4cm and a mean HJA of 77,0 degrees were obtained including all subjects. There was a strong correlation between the SRT and HJA measurements (r=.66). There were a difference between boys and girls in Back(p=.0019) and HJA measurements (p=.015). The results of this study suggest that measurements for the SRT and HJA were correlated than Back. The HJA measurements guide treatment more effectively than do Back length and SRT measurements.

• Nuclear Engineering and Technology
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• v.41 no.7
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• pp.945-952
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• 2009

The Three Mile Island Unit 2 (TMI-2) accident provides unique full scale data, thus providing opportunities to check the capability of codes to model overall plant behavior and to perform a spectrum of sensitivity and uncertainty calculations. As part of the TMI-2 analysis benchmark exercise sponsored by the Organization for Economic Cooperation and Development Nuclear Energy Agency (OECD NEA), several member countries are continuing to improve their system analysis codes using the TMI-2 data. The Republic of Korea joined this benchmark exercise in November 2005. Seoul National University has analyzed the TMI-2 accident as well as the currently proposed alternative scenario along with a sensitivity study using the Modular Accident Analysis Program Version 4.03 (MAAP4.03) code in collaboration with the Korea Hydro and Nuclear Power Company. Two input files are required to simulate the TMI-2 accident with MAAP4: the parameter file and an input deck. The user inputs various parameters, such as volumes or masses, for each component. The parameter file contains the information on TMI-2 relevant to the plant geometry, system performance, controls, and initial conditions used to perform these benchmark calculations. The input deck defines the operator actions and boundary conditions during the course of the accident. The TMI-2 accident analysis provided good estimates of the accident output data compared with the OECD TMI-2 standard reference. The alternative scenario has proposed the initial event as a loss of main feed water and a small break on the hot leg. Analysis is in progress along with a sensitivity study concerning the break size and elevation.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.1
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• pp.239-257
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• 2007

Purpose : In the part of Ob & Gy disease, the health insurance application is very limited. This study has been performed for gaining the basic data of enlargement of insurance coverage and reform of the insurance system corresponded with real clinical conditions. Methods : The survey has been practiced twice, the subjective questionnaire was used at the first survey. Then the questionnaire written using the results of first survey was distributed to the Korean medical doctors(KMD) who participated in the autumn symposium of the society of Oriental Obstetrics & Gynecology. Results : 1. The main Ob & Gy disease that the acupuncture treatment has been used actually or thought be positively necessary on the clinic were Dysmenorrhea(including premenstrual syndrome), Climacteric syndrome, Menstrual disorder, Postpartum Pain syndrome. Amenorrhea, Low back pain with pregnancy, JingHa(pelvic tumor), Infertility etc. 2. The main additional complex the sick and wounded names given to visiting patients for Ob & Gy disease as the limits of acupuncture items of insurance coverage were Low back Pain(J10), Qi-stasis(B13.0), SimHwaHangYeom(C2l.1). 3. Suitable the sick and wounded name of Ob & Gy disease thought be added in BokGangNae(Intra-abdominal acupuncture: CV13 ${\cdot}$CV16${\cdot}$CV10). TuJa(Puncture each adjoining acu-points in one insertion : SP6-GB39), TuJa(PC6-TE5) among acupuncture items of insurance coverage were Dysmenorrhea(K05). Menstrual disorder(K02) and Dysmenorrhea(K05), Hyperemesis(K16.0). 4. Climacteric syndrome(K04) and Dysmenorrhea(K05) should be added as suitable the sick and wounded name of TuJa(SP6-GB39), and Postpartum pain syndrome(K29) as KwanJeolGangNea(Intra-articular acupuncture: S35, LE201). Conclusion : Standing on this study, additional survey to general KMD should be continued. And the academic verifications through the oriental medical literatures and RCT papers on acupuncture should be also required.

• Journal of the Korean association of regional geographers
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• v.21 no.2
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• pp.319-341
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• 2015

Eupseong (county seat) represents the Korean historic city which had constructed intentionally by central government during Joseon Dynasty. There were variety of government or county offices which named as Gaeksa, Dongheon, Nea, Jilcheong, and so on. Also, there are houses of the people in many Eupseong but not all of them. This study aims to reconstruct the landscape elements and its overall construction of Eupseong in the Late Joseon dynasty on the original land registration map(1913). For this purpose, the author underlines to set-up target period for reconstruction. This study considers the early 19th century in Joseon as completion period of Eupseong landscape, and then researches distribution of Eupseong and major elements of its landscape in national scale. Based on those results, the author tries to reconstruct location of major landscape elements and layout of Eupseong landscape in the early 19th century on the original land registration map in case of Taean Eupseong, Seosan Eupseong, and Haemi Eupseong in Chungcheongnam-do (province), Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.12
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• pp.654-662
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• 2017

When emergency core cooling system (ECCS) is operated during loss of coolant accident (LOCA) in a pressurized water reactor (PWR), pressurized thermal shock (PTS) phenomenon can occur as cooling water is injected into a cold leg, mixed with hot primary coolant, and then entrained into a reactor vessel. Insufficient flow mixing may cause temperature stratification and steam condensation. In addition, flow vibration may cause thermal stresses in surrounding structures. This will reduce the life of the reactor vessel. Due to the importance of PTS phenomenon, in this study, calculation was performed for Test 1 among six types of OECD/NEA ROSA tests with ANSYS CFX R.17. Predicted results were then compared to measured data. Additionally, because temperature difference between the hot coolant at the inlet of the cold leg and the cold cooling water at the inlet of the ECCS injection line is 200 K or more, buoyancy force due to density difference might have significant effect on thermal-hydraulic characteristics of flow. Therefore, in this study, the necessity to include buoyancy force term in governing equations for accurate prediction of single phase thermal stratification in both cold legs and downcomer by ECCS injection was numerically studied.

• Food Science and Preservation
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• v.13 no.5
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• pp.581-588
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• 2006

Dynamic changes of free sugar and amino acid in the mixture of red bean paste sediment by corn syrup concentration and heating conditions were monitored. Glucose and fructose contents of red bean paste increased with an increasing blown color intensity. Amino acid content was affected by the heating temperature, increased with an increase in browning color intensify. Browning color intensity of each samples increased up to $95^{\circ}C$, but decreased above $95^{\circ}C$. This result was the same tend as changes of glucose and amino acid. The result of correlation coefficients among free sugar amino acid and browning color intensity show that increase in browning color intensity was not correlated directly with changes of free sugar and amino acid content. It seems that the contents of free sugar and amino acid resolved from saccharides and protein were much mote than contents nea for browning reaction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3698-3707
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• 2015

In this study, wet surface heat transfer and friction characteristics of non-symmetric slit-finned heat exchangers are experimentally investigated. Louver-finned heat exchangers are also tested for comparison purpose. The effect of fin pitch on j and f factor is negligible. Louver fin samples yield higher j and f factors than slit fin samples. For one row, j and f factors of louver fin are 27% and 31% higher than those of slit fin. For two row, j and f factors of louver fin are 15% and 30% higher. Both j and f factor decrease as the number of tube row increases. For one row, average j/f ratios of slit fin samples are 3.4% larger than those of louver fin samples. For two row, average j/f ratios of slit fin samples are 11.5% larger. A new correlation was developed using the present data.