• 제목/요약/키워드: 상변화 문제

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Shielding Design Optimization of the HANARO Cold Neutron Triple-Axis Spectrometer and Radiation Dose Measurement (냉중성자 삼축분광장치의 차폐능 최적화 설계 및 선량 측정)

  • Ryu, Ji Myung;Hong, Kwang Pyo;Park, J.M. Sungil;Choi, Young Hyeon;Lee, Kye Hong
    • Journal of Radiation Protection and Research
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    • v.39 no.1
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    • pp.21-29
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    • 2014
  • A new cold neutron triple-axis spectrometer (Cold-TAS) was recently constructed at the 30 MWth research reactor, HANARO. The spectrometer, which is composed of neutron optical components and radiation shield, required a redesign of the segmented monochromator shield due to the lack of adequate support of its weight. To shed some weight, lowering the height of the segmented shield was suggested while adding more radiation shield to the top cover of the monochromator chamber. To investigate the radiological effect of such change, we performed MCNPX simulations of a few different configurations of the Cold-TAS monochromator shield and obtained neutron and photon intensities at 5 reference points just outside the shield. Reducing the 35% of the height of the segmented shield and locating lead 10 cm from the bottom of the top cover made of polyethylene was shown to perform just as well as the original configuration as radiation shield excepting gamma flux at two points. Using gamma map by MCNPX, it was checked that is distribution of gamma. Increased flux had direction to the top and it had longer distance from top of segmented shield. However, because of reducing the 35% of the height, height of dissipated gamma was lower than original geometry. Reducing the 35% of the height of the segmented shield and locating lead 10cm from the bottom of the top cover was selected. After changing geometry, radiation dose was measured by TLD for confirming tester's safety at any condition. Neutron(0.21 ${\mu}Svhr^{-1}$) and gamma(3.69 ${\mu}Svhr^{-1}$) radiation dose were satisfied standard(6.25 ${\mu}Svhr^{-1}$).

A Study on Retrieval of Storage Heat Flux in Urban Area (우리나라 도심지에서의 저장열 산출에 관한 연구)

  • Lee, Darae;Kim, Honghee;Lee, Sang-Hyun;Lee, Doo-Il;Hong, Jinkyu;Hong, Je-Woo;Lee, Keunmin;Lee, Kyeong-sang;Seo, Minji;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.34 no.2_1
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    • pp.301-306
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    • 2018
  • Urbanization causes urban floods and urban heat island in the summer, so it is necessary to understanding the changes of the thermal environment through urban climate and energy balance. This can be explained by the energy balance, but in urban areas, unlike the typical energy balance, the storage heat flux saved in the building or artificial land cover should be considered. Since the environment of each city is different, there is a difficulty in applying the method of retrieving the storage heat flux of the previous research. Especially, most of the previous studies are focused on the overseas cities, so it is necessary to study the storage heat retrieval suitable for various land cover and building characteristics of the urban areas in Korea. Therefore, the object of this study, it is to derive the regression formula which can quantitatively retrieve the storage heat using the data of the area where various surface types exist. To this end, nonlinear regression analysis was performed using net radiation and surface temperature data as independent variables and flux tower based storage heat estimates as dependent variables. The retrieved regression coefficients were applied to each independent variable to derive the storage heat retrieval regression formula. As a result of time series analysis with flux tower based storage heat estimates, it was well simulated high peak at day time and the value at night. Moreover storage heat retrieved in this study was possible continuous retrieval than flux tower based storage heat estimates. As a result of scatter plot analysis, accuracy of retrieved storage heat was found to be significant at $50.14Wm^{-2}$ and bias $-0.94Wm^{-2}$.

Oxidation of Geosmin and 2-MIB in Water Using $O_3/H_2O_2$: Kinetic Evaluation (오존과 과산화수소를 이용한 Geosmin과 2-MIB 산화: 동력학적 평가)

  • Lee, Hwa-Ja;Son, Hee-Jong;Roh, Jae-Soon;Lee, Sang-Won;Ji, Ki-Won;Yoo, Pyung-Jong;Kang, Lim-Seok
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.7
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    • pp.826-832
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    • 2007
  • Unpleasant tastes and odors in drinking water cause same problems for water utilities across Korea. Even though tastes and odors do not create health problems, they are main concerns for consumers who determine the safety of their drinking water. In this study, two different odor producing compounds(geosmin 2-MIB) in the Nakdong river water and rapid sand filtered rater were treated by advanced oxidation of $O_3/H_2O_2$ process. The experimental results showed that the removal efficiency of geosmin with the use of 5 mg/L of $O_3$ and $H_2O_2$ was higher than efficiency with the use of $O_3$ alone for both the raw water and the sand filtered water. And in general, the removal efficiency of geosmin was higher than 2-MIB in the sand filtered water. Under the range of $O_3$ concentration $0.5\sim2.0$ mg/L, the removal rate constants(k) of geosmin for the raw and sand filtered waters, and the one of 2-MIB in the sand filtered water were increased rapidly as doses of $O_3$, and $H_2O_2$, increased. The removal rate constants(k) do not increase any more when $H_2O_2/O_3$ ratio increases above the optimum ratio. The optimum ratio of $H_2O_2/O_3$, dose was $1.0\sim2.0$ for both geosmin and 2-MIB. The removal rate constant(k) becomes lower when OH radical consuming materials are present in raw water. The half-life of geosmin decreased rapidly as the $O_3$ and $H_2O_2$ doses increase in the sand filtered water. The half life decreased about 8.5 times with the use of 2 mg/L of $O_3$ and 10 mg/L of $H_2O_2$ than with the use of 2 mg/L of $O_3$ alone for the sand filtered water.

Phenotype-genotype correlations and the efficacy of growth hormone treatment in Korean children with Prader-Willi syndrome (프래더 윌리 증후군의 유전학적 발병 기전에 따른 표현형 및 성장 호르몬 치료 효과에 관한 연구)

  • Bae, Keun Wook;Ko, Jung Min;Yoo, Han Wook
    • Clinical and Experimental Pediatrics
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    • v.51 no.3
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    • pp.315-322
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    • 2008
  • Purpose : Prader-Willi syndrome (PWS) is a complex genetic disorder, caused by the deletion of the paternally derived 15q11-13 region or the maternal uniparental disomy of chromosome 15 (mUPD(15)). In this study, we compared phenotypic differences between those patients whose disease was caused by microdeletion and those caused by mUPD(15). In addition, a comparison of the efficacy of growth hormone (GH) therapy between these two PWS genotypes was analyzed. Methods : Fifty-three patients were diagnosed as having PWS based on molecular and cytogenetic analyses and clinical features. Data that included maternal age, birth weight, a feeding problem in the neonatal period, cryptorchidism, developmental delay or mental retardation, short stature, hypopigmentation, changes in height, weight, and body mass indexes (BMI) before and after GH treatment were obtained by a retrospective review of medical records. The data from the patients with microdeletion were compared with those from the patients with mUPD(15). Results : Of the 53 patients with genetically confirmed PWS, 39 cases had microdeletion and 14 mUPD(15). Maternal ages were significantly higher in the mUPD(15) group, and hypopigmentation and a feeding problem in the neonatal period were more frequent in the microdeletion group. Growth hormone was administered to 20 patients [14 with microdeletion, 6 with mUPD(15)]. There were no differences between the two groups in height velocity, weight and height SDS, and BMI after GH therapy. Conclusion : Phenotype and genotype correlations were observed in Korean PWS patients, such as more advanced maternal ages in the mUPD(15) group and more feeding problems and hypopigmentations in the microdeletion group. Further long-term prospective studies are needed to correlate other aspects of the phenotypes.

Reduction of Carbon-Dioxide Emission Applying Carbon Capture and Storage(CCS) Technology to Power Generation and Industry Sectors in Korea (국내 전력 발전 및 산업 부문에서 탄소 포집 및 저장(CCS) 기술을 이용한 이산화탄소 배출 저감)

  • Wee, Jung-Ho;Kim, Jeong-In;Song, In-Sung;Song, Bo-Yun;Choi, Kyoung-Sik
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.9
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    • pp.961-972
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    • 2008
  • In 2004, total emissions of Greenhouse Gases(GHGs) in Korea was estimated to be about 590 million metric tons, which is the world's 10th largest emissions. Considering the much amount of nation's GHG emissions and growing nation's position in the world, GHG emissions in Korea should be reduced in near future. The CO$_2$ emissions from two sub-sections of energy sector in Korea, such as thermal power plant and industry section(including manufacturing and construction industries), was about 300 million metric tons in 2004 and this is 53.3% of total GHG emissions in Korea. So, the mitigation of CO$_2$ emissions in these two section is more important and more effective to reduce the nation's total GHGs than any other fields. In addition, these two section have high potential to qualitatively and effectively apply the CCS(Carbon Capture and Storage) technologies due to the nature of their process. There are several CCS technologies applied to these two section. In short term, the chemical absorption technology using amine as a absorbent could be the most effectively used. In middle or long term, pre-combustion technology equipped with ATR(Autothermal reforming), or MSR-$H_2$(Methane steam reformer with hydrogen separation membrane reactor) unit and oxyfuel combustion such as SOFC+GT(Solid oxide fuel cell-Gas turbine) process would be the promising technologies to reduce the CO$_2$ emissions in two areas. It is expected that these advanced CCS technologies can reduce the CO$_2$ avoidance cost to $US 8.5-43.5/tCO$_2$. Using the CCS technologies, if the CO$_2$ emissions from two sub-sections of energy sector could be reduced to even 10% of total emissions, the amount of 30 million metric tons of CO$_2$ could be mitigated.

Introduction and Application for Advanced Group Underwriting Skill (단체보험 언더라이팅 선진기법 도입방안)

  • Kim, C.N.;Back, J.K.;Lee, S.H.;An, J.W.;Chung, S.W.;Lee, S.M.;Jang, J.H.
    • The Journal of the Korean life insurance medical association
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    • v.22
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    • pp.139-169
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    • 2003
  • 국내 보험 산업은 경제발전에 따라 많은 성장을 이루어왔으나 단체보험은 보험 회사의 외부적 또는 내부적 환경으로 인해 활성화가 미흡한 상황이다. 개인보험시장의 포화, 해외시장에서 단체보험의 지속적인 성장, 사회보험 민영화 논의, 방카슈랑스와 보험시장의 개방 등 급격한 변화를 겪고 있는 보험영업환경을 고려한다면 향후 확대될 기업복지시장에서의 성공적 역할수행을 위해서는 단체보험 영업과 지원시스템의 보완이 시급한 과제라고 할 수 있다. 특히 언더라이팅 기법은 단체보험의 핵심역량이며 회사의 경쟁력 강화와 사차익 안정화를 위해서는 단체보험 인수기법의 선진화가 필수요건이다. 단체보험은 대수의 법칙, 수지상등의 원칙 등 보험의 기본원리라는 측면에서는 개인보험과 다른 점이 없지만 하나의 계약을 통해 집단의 피보험자에게 보장을 제공하기 때문에 가지게 되는 역선택 축소, 비용절감, 기업에 의한 1차선택 등 몇 가지 특성들은 인수기법에서의 차이를 필요로 한다. 하지만 국내의 단체보험 언더라이팅은 기본개념조차 제대로 정립되어 있지 못한 초기단계로 단체보험의 특성을 제대로 반영할 수 있는 위험평가를 위해서는 선진기법의 도입이 절실하다. 첫째, 자유보장한도(FREE COVER LIMIT)의 도입이다. 자유보장한도는 단체에 대한 위험과 피보험자 개인의 위험을 구분하는 기준으로 자유보장한도내의 피보험자에 대해서는 고지나 의적 검사를 요구하지 않고 개인별 언더라이팅을 하지 않으며 거절체나 표준하체이더라도 자유보장한도 금액까지는 나머지 정상 피보험자들과 동일한 보장을 제공하는 것을 말한다. 이는 피보험자별 위험을 중심으로 심사하고 있는 현재의 국내 단체보험 인수방법에서 발생되는 고객측 불만과 심사의 비효율성을 개선할 수 있는 방안이다. 둘째, 단체별 특성에 따른 보험요율 차등화이다 단체는 산업의 종류, 피보험자의 직무, 지역적 위치, 크기(피보험자수), 성별구성비 등 여러 가지 특성들을 가지고 있으며 이런 특성들은 보장급부에 따라 발생위험에 영향을 미칠 수 있다. 하지만 현재 나이와 성별에 따라서 피보험자별로 정해지는 요율체계만으로는 이런 위험들을 적절하게 반영하지 못하고 단체별 형평성에도 문제가 생긴다. 따라서 정확한 data 구축을 통해 단체 특성별로 어떤 보장에 어느 정도로 위험 발생에 영향을 미치는지를 분석하여 보험요율을 차등부과 할 수 있는 체계를 갖추어야 한다. 셋째, 경험을 활용한 보험료 산정기법이다. 이것은 개인보험과 구분되는 가장 큰 단체보험만의 특성이라 할 수 있는데 해당 단체의 과거 경험 data 즉 청구로 인한 지급금액을 토대로 당해 계약 보험료를 결정하는 방법이다. 이를 위해서는 과거 경험 data가 얼마나 신뢰할 수 있는 지의 정도(신뢰도)를 측정하는 것이 필요하다. 과학적이고 효율적인 단체보험 인수를 위해서 경험율의 활용은 반드시 이루어져야 할 선결과제이다. 넷째, 관련규정의 정비가 필요하다 단체보험의 특성을 갖기 위해서는 가입가능한 피보험자들의 자격규정(eligibility), 활동적근무 조건(actively at work)이 요구되어야 하며 참여비율(가입비율)과 보장수준의 구성방법에 대해서도 가이드라인 설정을 통해 역선택을 최소화 할 수 있는 제도적 보완이 마련되어야 한다. 이런 선진인수기법의 도입과 함께 단체보험 언더라이터의 필요역량을 개발하고 향상시키는 노력도 병행되어야만 종합금융화, 대형화가 진전되면서 대경쟁의 구도로 바뀌고 있는 국내 보험시장에서의 경쟁력 확보가 가능할 것이다.

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A Study about modification of Gejitang that showed on sympton and prescription about Soumin (소음인(少陰人) 병증(病證) 및 처방(處方)에 나타난 계기장(桂技場)의 변용(變用)에 대한 고찰(考察))

  • Kim, Jeong-hee;Song, Jeong-mo
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.201-220
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    • 1999
  • We got these results after studying about modification of Gejitang(桂枝湯) that showed on sympton and prescription about Soumin(少陰人). 1. There are totally eleven prescriptions related to Gejitang appeared on Dongyi-Soose-Bowon(東醫壽世保元). Among them, one is prescription of Danguisayoktang(當歸四逆湯) in prescription of Discussion of Cold Induced Disorder(傷寒論) and another is Gejibujatang(桂枝附子湯) in Won-Myung dynasty period(元明時代). There are nine prescriptions in LeeJae-Ma(李濟馬)'s pre-scription and we can see there are many prescriptions used prescriptions related to Gejitang for Mang Yang(亡陽). 2. Pre-scriptions related to Gejitang has seven prescriptions in Extra-disease(表病證), and two prescriptions in Intra-disease(裏病證) which are analyzed as modified prescription from Gejitang. 3. Although 藿香正氣散, 香蘇散, 芎歸香蘇散, 八物君子湯 etc. are not modified prescriptions of Gejitang, We can see that its are brought up to be on the same with alternative remedy of Gejitang in each step of symptoms. 4. Symptoms are exactly classified in Soumin, the prescription which is used in different symptoms of diseases is similar in raw materials. It's because the remedy of Acending and Descending(升降) is used under the same purpose that maintain Yangnan Qi(陽暖之氣). 5. We could realize that Panax gienseng(人蔘), Cinnamomum Cassia(肉桂) and Aconitum Carrnichali(附子) are commonly important to reinforce Yangnan Qi because the more disease got worse, the more patient lost Yangnan Qi on both Extra-disease and Intra-disease in the Soumin's disease.

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Establishment of Waste Collection and Transportation System for Composting I. Estimation of Unit Garbage Generation (퇴비화촉진을 위한 쓰레기 수거체계의 확립 I. 음식물찌꺼기 원단위 발생량의 산정)

  • Shin, H.S.;Hwang, E.J.;Kang, H.;Lee, S.J.;Jang, W.
    • Journal of the Korea Organic Resources Recycling Association
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    • v.3 no.2
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    • pp.25-36
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    • 1995
  • It is important to separate the compostables from waste for successful operation of composting plant, since various compositions are mixed in it. For the separation of compostables, it is necessary to estimate total amounts of compostables from several sources. Based on it, required capacity and number of composting plant as well as proper waste collection and transportation system can be determined. So, amounts of garbage, major target material for composting. were estimated in this study. In survey of unit garbage generation(UGG). different estimation results would be obtained depending on the basis of its measurement. However, previous researches did not consider it. In this paper, the correlations between area and the number of user of garbage source were analyzed to find the related equations which were apllyed to estimation of total generation. Obtained results are as the following. Relative variations of measured UGG based on area and custumer are 62.5 and 52.8, respectively. In linear regression, related equation between area and custumer was Y=0.244X+59.0 (X=area, Y=custumer). The correlation factor r is 0.904. Equation Y=616.5X/(X+1215.4) was also obtained from linear regression using Monod equation (r=0.720). From the first order equation and measured data of UGG based on custumer, amounts of garbage generation from restaurant in Seoul and the whole country were calculated to 2043.9 ton/d and 9014.0 ton/d, respectively. But, the values calculated from measured data of UGG based on area were as low as 821.3 ton/d Cin Seoul) and 3821.0 ton/d(in the whole country). Consequently, the measurement of unit garbage generation based on the number of custumer was more favorable to lessen the points of survey and to guarantee the representative values. Especially, it would fit well on restaurant having statistics of area.

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A Study on the Applicability of Social Security Platform to Smart City (사회보장플랫폼과 스마트시티에의 적용가능성에 관한 연구)

  • Jang, Bong-Seok
    • Journal of the Korea Convergence Society
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    • v.11 no.11
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    • pp.321-335
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    • 2020
  • Given that with the development of the 4th industry, interest and desire for smart cities are gradually increasing and related technologies are developed as a way to strengthen urban competitiveness by utilizing big data, information and communication technology, IoT, M2M, and AI, the purpose of this study is to find out how to achieve this goal on the premise of the idea of smart well fair city. In other words, the purpose is to devise a smart well-fair city in the care area, such as health care, medical care, and welfare, and see if it is feasible. With this recognition, the paper aimed to review the concept and scope of smart city, the discussions that have been made so far and the issues or limitations on its connection to social security and social welfare, and based on it, come up with the concept of welfare city. As a method of realizing the smart welfare city, the paper reviewed characteristics and features of a social security platform as well as the applicability of smart city, especially care services. Furthermore, the paper developed discussions on the standardization of the city in terms of political and institutional improvements, utilization of personal information and public data as well as ways of institutional improvement centering on social security information system. This paper highlights the importance of implementing the digitally based community care and smart welfare city that our society is seeking to achieve. With regard to the social security platform based on behavioral design and the 7 principles(6W1H method), the present paper has the limitation of dealing only with smart cities in the fields of healthcare, medicine, and welfare. Therefore, further studies are needed to investigate the effects of smart cities in other fields and to consider the application and utilization of technologies in various aspects and the corresponding impact on our society. It is expected that this paper will suggest the future course and vision not only for smart cities but also for the social security and welfare system and thereby make some contribution to improving the quality of people's lives through the requisite adjustments made in each relevant field.

The NACUFOK Business Consulting's Influence on the Management Performance of the Primary Credit Unions (신협중앙회 경영컨설팅이 단위신협의 경영성과에 미치는 영향)

  • Kang, Seong Moo;Ryu, Duk Wi
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.4
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    • pp.101-112
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    • 2012
  • Business consulting which aims at advising overall management, comparative advantage in competitive environment, administration and so forth is deemed to be significant so that a credit union may flexibly respond to rapid and complicated financial environment. Accordingly, business consulting has been initiated and implemented in credit union since 2002, which seemingly leads to positive outcome to enhance its competitiveness. However, very few research exists which analyze the credit union's competitiveness and business performance after the business consulting. Thus, the research intends to verify how consulting influences on management performance by its various factors. With the above studies in mind, hypothesis is formed that the characteristics of a consulting comsumer and the characteristics of supplier will give a meaningful impact on management performance. The test shows the result as followings: Firstly, a primary credit union's trust and NACUFOK's expertise demonstrate that they are closely relevant to financial and non financial management performance. Secondly, support and willingness to apply states that they influences on non financial performance, while no direct impact is found to financial performance. Thirdly, NACUFOK's capability is rarely interrelated to financial and non financial performance. The present study implies that the credit union as a consulting beneficiary should participate in the consulting, accept the result, and make effort to solve the management problems. In addition, NACUFOK as a consulting supplier should initiate the organization in exclusive charge, perform the professional group, and foster the professional consultant for the development of consulting method, the improvement of consulting process, and the specialization of consultant including the enhancement of core competencies. When these perspectives are sufficient, it will be connected to the management outcomes, further, it will be boosted up the competitiveness of the Credit Union. Hopefully the present study helps to motivate the consulting of primary credit union, boost up the effectiveness of consulting, further, providing the perspective on consulting the credit union. And these may result in the indication of consulting development direction and the competitiveness of Credit Union.

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