• 제목/요약/키워드: U-Value

검색결과 2,054건 처리시간 0.028초

잡지 『농민생활』과 일상 아카이브 연구 (A Study on the Magazine Farmer's Life and the Daily Archives)

  • 원종훈
    • 기록학연구
    • /
    • 제68호
    • /
    • pp.151-204
    • /
    • 2021
  • 잡지는 동시대 보통사람들의 일상을 담고 있기도 하다. 이러한 특성은 일상 아카이브의 가능성으로 작용한다. 본 연구는 대전에서 발행된 잡지 『농민생활』의 내용과 기록가치를 분석하여 일상 아카이브로 구축하는 데 있다. 이를 위해, 1954년부터 1967년까지 14년 간 발행된 『농민생활』에 수록된 기사를 대상으로 기사의 내용을 분류하고 분석하였다. 『농민생활』의 분석을 통해 나온 결과는 다음 다섯 가지로 정리할 수 있다. 첫째, 대전지역의 민간기록물의 가치를 알 수 있었다. 둘째, 사회 각 분야에서 활동하던 인물들의 인명 정보를 수집할 수 있었다. 정치인, 농업학자, 교수, 의사, 만화가 등 전문직업별로 분류하였다. 셋째, 농업분야조직에 관한 정보를 수집할 수 있었다. 정부조직, 민관조직, 미국원조 및 4H조직이 있었던 것으로 파악되었다. 넷째, 기독교잡지, 문학, 예술분야에서 오기 또는 누락되어 있거나 추정에 의존하는 기록들 중에서 수정할 수 있는 내용을 찾아 제시하였다. 다섯째, 농촌사회와 농민들의 일상생활을 시리즈로 분류하여 일상 아카이브로 구성할 수 있었다. 본 연구는 1950, 60년대 농촌사회와 농민의 일상세계에 접근하기 위한 기초자료로서 제시하였다.

교육 격차 해소를 위한 민간단체의 교육지원 활동: 미국의 Teach For America와 한국의 Dream Touch For All을 중심으로 (Educational Support Activities of Private Organizations to Alleviate the Educational Gap: Focusing on Teach For America in USA and Dream Touch For All in Korea)

  • 민윤경;박근아;이해니
    • 비교교육연구
    • /
    • 제28권6호
    • /
    • pp.85-109
    • /
    • 2018
  • 본 논문은 동일한 목표를 가지고 설립된 미국의 'TFA'와 한국의 '드림터치포올' 두 단체를 1) 목표 및 핵심 가치, 2) 교사 지원 자격 및 양성 과정, 3) 교육적 성과의 측면에서 비교하고 그 두 단체가 다르게 운영될 수밖에 없는 각국의 교사양성 체제의 성격까지 살펴보는 것을 목적으로 하였다. 분석 결과, 두 단체는 교육 불평등 해소라는 목표 하에 교육 소외계층의 학업 성취 향상을 위해 교사의 역할에 주목하였다는 공통점을 보인다. 그러나, 이를 위해 미국의 TFA가 공교육 내에서 기능할 수 있었던 반면, 한국의 드림터치포올은 공교육의 보완재로서의 역할을 수행하고 있다. 미국의 경우 TFA와 같은 대안 교사 단체에서의 교원 양성을 허용하는 '준개방적' 교원 양성 체제로 변화한 반면, 한국에서는 이러한 대안 교사 단체가 허용되지 않는 '폐쇄적' 교원 양성 체제이기 때문이다. 이러한 이유로 두 단체는 핵심 가치, 교사 양성 및 운영 프로그램 등에서 차이를 보였고 그 결과 지향하는 교육 모델 또한 다르게 설정하고 있음을 알수 있다. 연구 결과를 바탕으로 결론 및 논의 부분에서는 두 단체의 활동을 통해 결국 한국 교육에서 가장 중요한 본질적인 문제는 교사라는 근본적인 문제를 제기하였다.

The Effect of Export on R&D Cost Behavior: Evidence from Korea

  • Chang Youl Ko;Hoon Jung
    • Journal of Korea Trade
    • /
    • 제26권5호
    • /
    • pp.23-38
    • /
    • 2022
  • Purpose - This research intends to find out whether R&D cost stickiness shows differentiated aspects depending on exports in Korea. A cost behavior that indicates a lower rate of costs decrease when sales decrease than the rate of costs increase when sales increase is called cost stickiness. This sticky cost behavior is caused by considering the adjusting costs. This study aims to empirically verify that R&D cost stickiness is greater in export firms than in non-export firms. We also investigate the effect of exports on R&D cost stickiness is nonlinear. Design/methodology - We obtain data for the analysis from Kis-Value and TS2000 from 2012 to 2020. This study tests for R&D cost stickiness of exports using the cost stickiness model developed by Anderson et al. (2003) that is used in a lot of prior literature. To explore the nonlinear behavior of R&D cost stickiness we include a quadratic term of exports in our model. Findings - The results of our analysis are as follows. First, we observed that R&D costs of export firms are more sticky than that of non-export firms. Our result indicated that export firms are less likely to reduce R&D costs in decreasing sales periods in preparation for future sales recovery. Second, our empirical evidence shows that export firms view R&D costs much favorably. However, we hypothesize that the effect of export intensity on R&D costs may not necessarily be linear. Our result shows the effect of exports intensity on R&D stickiness is thus nonlinear, forming a reverse U-shaped curve. When export intensity exceeds a certain threshold, the growth rate of R&D costs appears to be viewed negatively. Firms with relatively high export intensity do not support R&D costs, viewing them as taking away firms' resources from other more productive costs. On the contrary, those with export intensity under the threshold view R&D costs as beneficial and therefore promote further R&D costs when revenue decreases. Originality/value - The results of this research can contribute academically to the expansion of empirical research on R&D cost stickiness. R&D cost stickiness varies by industry. As a result of our research, the managers of export firms recognize the importance of R&D to lead innovation. We expected that this research contributes to further studies on R&D costs and cost stickiness. Second, this research has implications from a business perspectives. Our findings of export firms' R&D stickiness suggest that export firms' managers should consider keeping the stickiness of R&D when revenue decreases because it is essential for exporting firms to maintain their R&D stickiness to secure long-term competitiveness. R&D stickiness can be used on a practical basis to emphasize the need for continuous investment in exporting firms' R&D activities.

엔트로피 개념을 이용한 관수로내의 유속분포에 관한 연구 (A Study on The Velocity Distribution in Closed Conduit by Using The Entropy Concept)

  • 추태호;옥치율;김진원;맹승진
    • 대한토목학회논문집
    • /
    • 제29권4B호
    • /
    • pp.357-363
    • /
    • 2009
  • 일반적으로 사용되는 관수로의 평균유속을 구하려면 Darcy-Weisbach의 마찰손실수두공식을 사용하면 되나, 그러나 이 식의 마찰손실계수 f는 Reynolds수와 상대조도(${\varepsilon}$/d)의 함수이므로 사용하기에 매우 불편하며 따라서 보다 편리한 식이 요구된다. 이에 본 연구에서 Chiu 유속공식의 신뢰성과 정확성을 증명하기 위하여 관수로에서 비삽입식 유속측정 장치인 레이저 유속계(Laser Doppler Velocimeter: LDV) 및 초음파 유량계(Ultrasonic Flowmeter: U/F), 삽입식 유속측정장치인 피토관 (Pitot Tube)을 이용하여 실측한 유속측정 자료와 Chiu의 공식을 이용한 유속분포가 매우 잘 일치함을 증명하였다. 유량의 증감에 관계없이 실험실 수로에서의 최대유속과 평균유속간의 이론적인 선형관계를 증명함으로써 관수로내 유속의 평형상태, 즉 엔트로피 파라미터 M값에 대응하는 평형상태에 도달하려 하고 이 평형상태를 지속적으로 유지하려고 하는 경향이 있음을 증명하였다. 또한, 한 단면을 대표하는 엔트로피 파라미터 M값이 결정되면 최대유속이 발생하는 지점에서의 유속 측정만으로 단면 전체의 평균유속을 쉽게 구할 수 있고 이로부터 간단히 유량을 산정할 수 있음을 증명하였으며, 이는 추후 관수로 설계 및 운영관리 시 가장 중요한 평균유량을 측정할 수 있는 이론적인 도구로 사용될 수 있음을 의미하는 것이다.

A Comparative Analysis on the Competitiveness of Korean and Japanese Fashion Industry by Applying Generalized Double Diamond Model

  • Son, Mi Young;Kenji, Yokoyama
    • Asia Marketing Journal
    • /
    • 제15권1호
    • /
    • pp.57-81
    • /
    • 2013
  • The purpose of this paper is to seek ways to improve the competitiveness of Korea's fashion industry by utilizing the source of competitiveness of Japan's fashion industry, which represents the world's leading countries in terms of fashion, so that Korea can better enter the global fashion market. The study shall first compare the competitiveness of the Japanese and Korean fashion industries by utilizing the generalized double diamond model; second, provide an understanding of what the Japanese fashion industry can offer to Korean fashion industry and companies - that is, understand what the Japanese fashion industry's competitive edge is; and third, study the kind of global competitiveness that Korea's fashion industry must achieve. To adopt a generalized double diamond model to compare the competitiveness of the Korean and Japanese fashion industries, we selected 31 sub-variables to act as determinants of the model. That is, we extracted 31sub-variables by doing research of literature to analyze national competitiveness of the fashion industries. To measure these 31 sub-variables, secondary data was gathered. We collected data related to each sub-variable from various sources of Korea and Japan. And to calculate the competitiveness index, we took three steps with reference to previous studies. We found that status of the fashion industry of the two countries as it stands. That is, Japan is an advanced country of which fashion industry is domestic market-oriented while Korea is a small open economy that mainly focuses on the foreign market. Out of 31 proxy variables, Korea's fashion industry shows higher measurements relating to production and export than Japan, but Japan's fashion industry reports higher measurements than Korea in the fields of R&D, design and brand power, the rate of value added, the efficiency of companies and globalization. In order for Korea's fashion industry to achieve competitiveness in the global market, it should pursue the following development direction. First, it is very difficult for Korea to follow the footsteps of the U.S. and Japanese fashion industries that are able to take advantage of economies of scale, because Korea is smaller than those countries. Therefore, in the case of small economies such as Singapore, strengthening of international activities will practically improve domestic determinants that Korea should improve its domestic diamond by enhancing the current competitiveness of its international diamond. In other words, Korea needs to further endeavor to develop and expand global resources and markets as well as improve its competitiveness in terms of R&D, design and brand power, the rate of value-added, and the efficiency of companies. As the Korean fashion industry shows relatively advanced level of information technology and the fashion education system, it has considerable potential to grow. Korea is expected to have a huge growth potential since it has relatively higher level of information technology, fashion education system and activities than those of Japan in both the domestic diamond and international diamond. In particular, a better environment is laid out before Korea to gain competitiveness in the fashion industry due to the recently growing influence of the Korean Wave that Korea is expected to grow as a leader in the Asian market as well as in the global market.

  • PDF

가치구조와 환경소비주의에 관한 타 문화간 비교연구: 한국과 미국 소비자사례 (A Cross-Cultural Study of Value Structure and Environmental Consumerism: The Case of Korean and United States Consumers)

  • 김연신;최세정;노라 리폰
    • Asia Marketing Journal
    • /
    • 제10권4호
    • /
    • pp.35-64
    • /
    • 2009
  • 친환경구매행위에 대한 이해를 도모하고 소비자에게서 나타나는 환경의식과 실제 행위간의 차이를 좁히기 위한 노력으로, 본 논문은 소비자들의 차별적 환경태도 및 행위의 원인을 소비자의 가치구조와 연결시켰다. 이를 위해 본 연구에서는 소비자가치구조와 친환경소비주의간의 관계를 설명하는 포괄적 연구모형을 제안하고 한국과 미국의 소비자를 대상으로 실증 분석하였다. 두 나라는 문화적 측면에서 이질적이며, 따라서 소비자들의 친환경성향과 관계 있는 가치체계도 다를 것이다. 연구를 위한 자료는 각 나라에 거주하는 대학생 소비자들을 대상으로 실시한 설문조사를 통해 수집되었으며 구조방정식모형을 이용하여 각 나라별 그리고 다중 집단 수준(multi-group level)에서 분석하였다. 분석결과, 특정 가치체계와 환경태도 및 친환경구매행위의 중요한 관련성이 발견되어진 반면, 구체적으로 고려된 세 가지 가치체계, 태도, 행위의 관계유형들이 두 나라 사이에 차이가 있는 것으로 나타났다. 즉, 소비자의 가치체계가 그들의 친환경태도 및 소비행위에 중요한 영향을 미치지만 어떤 가치체계가 어떻게 구매행위에 영향을 미치는지는 그 나라의 문화적 특성에 따라 다를 수 있음을 발견하였다. 본 연구의 결과는 글로벌 친환경마케팅을 시도하는 국제 마케터들에게 중요한 시사점을 제공한다.

  • PDF

Development and Validation of 18F-FDG PET/CT-Based Multivariable Clinical Prediction Models for the Identification of Malignancy-Associated Hemophagocytic Lymphohistiocytosis

  • Xu Yang;Xia Lu;Jun Liu;Ying Kan;Wei Wang;Shuxin Zhang;Lei Liu;Jixia Li;Jigang Yang
    • Korean Journal of Radiology
    • /
    • 제23권4호
    • /
    • pp.466-478
    • /
    • 2022
  • Objective: 18F-fluorodeoxyglucose (FDG) PET/CT is often used for detecting malignancy in patients with newly diagnosed hemophagocytic lymphohistiocytosis (HLH), with acceptable sensitivity but relatively low specificity. The aim of this study was to improve the diagnostic ability of 18F-FDG PET/CT in identifying malignancy in patients with HLH by combining 18F-FDG PET/CT and clinical parameters. Materials and Methods: Ninety-seven patients (age ≥ 14 years) with secondary HLH were retrospectively reviewed and divided into the derivation (n = 71) and validation (n = 26) cohorts according to admission time. In the derivation cohort, 22 patients had malignancy-associated HLH (M-HLH) and 49 patients had non-malignancy-associated HLH (NM-HLH). Data on pretreatment 18F-FDG PET/CT and laboratory results were collected. The variables were analyzed using the Mann-Whitney U test or Pearson's chi-square test, and a nomogram for predicting M-HLH was constructed using multivariable binary logistic regression. The predictors were also ranked using decision-tree analysis. The nomogram and decision tree were validated in the validation cohort (10 patients with M-HLH and 16 patients with NM-HLH). Results: The ratio of the maximal standardized uptake value (SUVmax) of the lymph nodes to that of the mediastinum, the ratio of the SUVmax of bone lesions or bone marrow to that of the mediastinum, and age were selected for constructing the model. The nomogram showed good performance in predicting M-HLH in the validation cohort, with an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.686-0.971). At an appropriate cutoff value, the sensitivity and specificity for identifying M-HLH were 90% (9/10) and 68.8% (11/16), respectively. The decision tree integrating the same variables showed 70% (7/10) sensitivity and 93.8% (15/16) specificity for identifying M-HLH. In comparison, visual analysis of 18F-FDG PET/CT images demonstrated 100% (10/10) sensitivity and 12.5% (2/16) specificity. Conclusion: 18F-FDG PET/CT may be a practical technique for identifying M-HLH. The model constructed using 18F-FDG PET/CT features and age was able to detect malignancy with better accuracy than visual analysis of 18F-FDG PET/CT images.

CT Angiography-Derived RECHARGE Score Predicts Successful Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion

  • Jiahui Li;Rui Wang;Christian Tesche;U. Joseph Schoepf;Jonathan T. Pannell;Yi He;Rongchong Huang;Yalei Chen;Jianan Li;Xiantao Song
    • Korean Journal of Radiology
    • /
    • 제22권5호
    • /
    • pp.697-705
    • /
    • 2021
  • Objective: To investigate the feasibility and the accuracy of the coronary CT angiography (CCTA)-derived Registry of Crossboss and Hybrid procedures in France, the Netherlands, Belgium and United Kingdom (RECHARGE) score (RECHARGECCTA) for the prediction of procedural success and 30-minutes guidewire crossing in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Materials and Methods: One hundred and twenty-four consecutive patients (mean age, 54 years; 79% male) with 131 CTO lesions who underwent CCTA before catheter angiography (CA) with CTO-PCI were retrospectively enrolled in this study. The RECHARGECCTA scores were calculated and compared with RECHARGECA and other CTA-based prediction scores, including Multicenter CTO Registry of Japan (J-CTO), CT Registry of CTO Revascularisation (CT-RECTOR), and Korean Multicenter CTO CT Registry (KCCT) scores. Results: The procedural success rate of the CTO-PCI procedures was 72%, and 61% of cases achieved the 30-minutes wire crossing. No significant difference was observed between the RECHARGECCTA score and the RECHARGECA score for procedural success (median 2 vs. median 2, p = 0.084). However, the RECHARGECCTA score was higher than the RECHARGECA score for the 30-minutes wire crossing (median 2 vs. median 1.5, p = 0.001). The areas under the curve (AUCs) of the RECHARGECCTA and RECHARGECA scores for predicting procedural success showed no statistical significance (0.718 vs. 0.757, p = 0.655). The sensitivity, specificity, positive predictive value, and the negative predictive value of the RECHARGECCTA scores of ≤ 2 for predictive procedural success were 78%, 60%, 43%, and 87%, respectively. The RECHARGECCTA score showed a discriminative performance that was comparable to those of the other CTA-based prediction scores (AUC = 0.718 vs. 0.665-0.717, all p > 0.05). Conclusion: The non-invasive RECHARGECCTA score performs better than the invasive determination for the prediction of the 30-minutes wire crossing of CTO-PCI. However, the RECHARGECCTA score may not replace other CTA-based prediction scores for predicting CTO-PCI success.

Sparkover Voltage Estimation of Standard Sphere Gaps for Negative Polarity by Calculation of Ionization Index

  • Nishikori, Yasuo;Kojima, Soji;Kouno, Teruya
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • 제4C권2호
    • /
    • pp.45-50
    • /
    • 2004
  • The field utilization factor (equation omitted) (the mean electric field / the maximum electric field) of standard sphere gaps was calculated by the charge simulation method, taking into account the ground plane and shanks. n changes mainly with g/r and slightly with 1$_1$, 1$_2$ and 1, where D=2r is the sphere diameter, g is the gap length, 1$_1$ and 1$_2$, respectively, are the lengths of the upper and lower shank, and t is the shank diameter. Generally, (equation omitted) increases as 1$_1$,1$_2$ and t each becomes larger. IEC standard 60052(2002) limits t$\leq$0.2D 1$_1$$\geq$1D and prescribes A=1$_2$+D+g where A is the height of the spark point on the upper sphere. Therefore, (equation omitted) is the largest when A=9D and the smallest when A=3D. The simple equation of a straight line, (equation omitted)=1- (g/3r), can generally be used as a representative value of (equation omitted) for a wide variety of sphere diameters that are permitted by the IEC standard. The maximum electric field E$_{m}$ at sparkover of standard air gaps has also been calculated by the relation E$_{m}$=V/(equation omitted)g). E$_{m}$ describes a U-curve for g/r, up to the sphere diameter of 1 m. Moreover, for 1.5-m and 2-m diameters and especially .for negative polarity, sparkover voltages have been calculated by integration of the ionization index.index.

Effect of Family Size and Genetic Correlation between Purebred and Crossbred Halfsisters on Response in Crossbred and Purebred Chickens under Modified Reciprocal Recurrent Selection

  • Singh, Neelam;Singh, Raj Pal;Sangwan, Sandeep;Malik, Baljeet Singh
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제18권1호
    • /
    • pp.8-12
    • /
    • 2005
  • Response in a modified reciprocal recurrent selection scheme for egg production was evaluated considering variable family sizes and genetic correlation between purebred and crossbred half sisters. The criteria of selection of purebred breeders included pullet's own performance, purebred full and half sisters and crossbred half sister's performance. Heritability of egg production of crossbreds (aggregate genotype) and purebred's was assumed to be 0.2 and genetic correlation between purebred and crossbred half sisters ($r_{pc}$) as 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, -0.1, -0.2, -0.3, -0.4, -0.5 and -1.0. Number of dams per sire to produce purebred and crossbred progenies assumed to be 5, 6, 7, 8, while number of purebred female progeny ($N_p$) and crossbred progeny ($N_c$) per dam were considered to be 3, 4, 5 and 6 in each case. Considering phenotypic variance as unity, selection indices were constructed for different combinations of dams and progeny for each value of $r_{pc}$. Following selection index theory, response in crossbred and purebred for egg production was computed. Results indicated that response in crossbreds depended mainly on crossbred family size and also on magnitude of$r_{pc}$ irrespective of its direction, and response was greater with large crossbred family size than the purebred families. Correlated response in purebreds depends both on magnitude and direction of $r_{pc}$ and was expected to be greater with large purebred family size only. Inclusion of purebred information increased the accuracy of selection for crossbred response for higher magnitude of$r_{pc}$ irrespective of its direction. Present results indicate that desirable response in both crossbred and purebred performance is a function of $r_{pc}$ and family sizes. The ratio of crossbred and purebred family sizes can be optimized depending on the objective of improving the performance of crossbreds and/or of purebreds.