• 한국콘텐츠학회논문지
• /
• 제20권7호
• /
• pp.223-232
• /
• 2020

본 연구의 목적은 토픽 모델링과 주제어 네트워크 분석방법을 활용하여, 20대 청년세대에 관한 연구동향을 분석하는 것이다. 이를 위해, 지난 10년간 국내에서 20대 청년을 대상으로 발표한 학술논문 530편을 분석하였다. 연구 결과, 핵심 주제어는 '소득', '프로그램', '창업', '문화'였고, 6개의 토픽(취업 지원 서비스, 가치관, 불안정한 삶, 정부 지원 정책, 종교관, 창업 지원 서비스)이 도출되었다. 또한, 연구를 통해 20대 청년세대는 높은 디지털 기술 효용감, 효율적인 디지털 정보의 소비 추구, 의미 전복적이고 심미적인 소비패턴, 자신의 정체성을 온라인 세계에서 찾고, 현실을 지향하는 모습을 보이는 것으로 나타났다. 분석 결과를 토대로, 세대 간 가치관 격차, 지역간 발전의 불균형 문제, 소득 불평등의 주요 양극화 문제를 제기하였고, 향후 대안적 정책으로 단편적이고 일회성에 그치는 미봉책이 아닌, 장기적으로 지속성 있는 20대 청년세대 문제 해결책을 제시해야 한다는 점을 제안하였다.

• 한국IT서비스학회지
• /
• 제17권2호
• /
• pp.83-100
• /
• 2018

Demand for stone products used as building materials is increasing. The construction industry, the value of the stone industry is sufficient, but the domestic stone industry is very lag regarding IT utilization. However, the overseas stone industry produces high-quality products using IT. In this study, we want to offer an IT application technology priority fit for the stone industries. We identify the current status and production process of the stone industries, then set the priority of various IT, so that obtain competitiveness in the domestic stone industries, and minimize the gap between the overseas stone industries. Therefore, we used AHP method; stone industry production processes were selected as the Enterprise Operation Management, Quarrying, Manufacturing, Construction and Maintenance of first-tier. The second-tier ones are consisted of 30 factors out of IT elements. Focus group interviews were conducted to confirm the validity of each factor. As a result, most important factors of first-tier was selected as the order of Manufacturing, Quarrying, Enterprise Operation Management, and Construction & Maintenance. The top 5 of 30 factors in the second-tier were selected Smart Sensor, Mobile Device, Robot of manufacturing, GIS of quarrying, and SCM of enterprise operation management. And the factor that relatively less important was GPS of construction and maintenance. If properly applied an IT application technology for stone industry, we expect to provide efficient production lines and increase customer satisfaction, which will ultimately expand the promotion for the industry and thus act as positive factor in promoting the stone industry.

• 대한수학회지
• /
• 제47권6호
• /
• pp.1147-1165
• /
• 2010

In this paper we compare a torsion free sheaf F on $P^N$ and the free vector bundle $\oplus^n_{i=1}O_{P^N}(b_i)$ having same rank and splitting type. We show that the first one has always "less" global sections, while it has a higher second Chern class. In both cases bounds for the difference are found in terms of the maximal free subsheaves of F. As a consequence we obtain a direct, easy and more general proof of the "Horrocks' splitting criterion", also holding for torsion free sheaves, and lower bounds for the Chern classes $c_i$(F(t)) of twists of F, only depending on some numerical invariants of F. Especially, we prove for rank n torsion free sheaves on $P^N$, whose splitting type has no gap (i.e., $b_i{\geq}b_{i+1}{\geq}b_i-1$ 1 for every i = 1,$\ldots$,n-1), the following formula for the discriminant: $$\Delta(F):=2_{nc_2}-(n-1)c^2_1\geq-\frac{1}{12}n^2(n^2-1)$$. Finally in the case of rank n reflexive sheaves we obtain polynomial upper bounds for the absolute value of the higher Chern classes $c_3$(F(t)),$\ldots$,$c_n$(F(t)) for the dimension of the cohomology modules $H^iF(t)$ and for the Castelnuovo-Mumford regularity of F; these polynomial bounds only depend only on $c_1(F)$, $c_2(F)$, the splitting type of F and t.

• 폴리머
• /
• 제33권5호
• /
• pp.420-428
• /
• 2009

In this study, the composites containing carbon black (CB) or carbon fibers were prepared, and the microwave absorbing properties and the absorption mechanism of them were investigated and discussed in the frequency range of 2-18 GHz, respectively. The optimum mass fraction of CB has been found as 6%, and the carbon fibers were discovered to absorb radar wave either under parallel or vertical polarization, the suitable gap distance between each bundle of which was 5 mm. According to the results of the single constitute absorber samples, the structured composites with the two kinds of absorbers combination were fabricated and studied at 2-18 GHz. The top layer absorbers affect the absorption performance a lot; the maximum reflection loss of composites with CB as top layer absorbers was -31.8 dB with the frequency range of 2.4 GHz below -10 dB, and the other type with CFs as the top layer absorbers obtained the reflection loss peak value of -31.4 dB with 2 GHz below-10 dB.

• 건축역사연구
• /
• 제19권2호
• /
• pp.67-83
• /
• 2010

The purpose of this research is to rethink Alvar Aalto's architecture on the basis of the aesthetic concept of play. This attempt is valid because he had asserted the importance of play in his design. But more fundamentally, his critical view of the instrumentalised rationalism implied the idea that a human being is "Man the Player" as well as "Man the Thinker", of which theory was elaborated in Johan Huizinga's Homo Ludens (1938). Premised on it, this paper investigated the evolution of the play idea in aesthetics and located Aalto's concept within the map. Summing up, his play was an intuitively grasped desire opposed to a rational requirement, which leads to a dialectical synthesis. This schema is similar to that of Schiller, in which Spiel reconciles the reason and the sense. However, Aalto's play could be differentiated into the "astonishingly rational" and "a jest", each of which roughly corresponds to the Spieltrieb (play impulse) and the sinnliche Trieb (sensuous impulse) in Schiller's thinking. On the other hand, Aalto's architecture illustrates play that could be interpreted as the overflow of surplus energy. This play is the very concept that can bridge the gap in the form-function formula of modern architecture. Aalto's play idea seemed to basically originate from his personality but its value must be confirmed by the Finnish litterateur Yrjo Hirn as Aalto mentioned in his statements (1953 & 1972). It appears that Aalto's play concept was materialised in architecture through his typical design language, such as the undulating wall, the aperspective space, the imitation of nature and the collage of heterogenous elements. However, we should be careful not to reductively analyse the application of play in practise. As Huizinga's comprehensive theory suggests, the play element exists in any cultural areas including any architectural activities. In conclusion, this paper argues that Alvar Aalto the Homo Ludens presented the possibility of critical rationalism in modern architecture by imbuing dry modernism with "the life enhancing charm" of "the art of play".

• 디지털융복합연구
• /
• 제15권10호
• /
• pp.467-483
• /
• 2017

본 연구는 스마트폰이 여성의 일상생활 속에서 어떠한 역할과 의미를 갖는지 탐구하기 위해, 20대 중국 여성에 대한 심층인터뷰를 실시했다. 연구결과, 스마트폰은 중국 여성의 소비활동, 여가활동, 사회적 교류활동 등 일상의 다양한 영역에 영향을 미치고 있었다. 여성 이용자들은 스마트폰을 통해 소비습관이 바뀌었으며, 다양한 애플리케이션 활용을 통해 많은 여가시간을 보내고 있는 것으로 나타났다. 그러나 구매상품, 검색정보, 콘텐츠 선택 등에 있어서는 소위 여성영역의 소프트웨어를 선택하고, 이러한 선택에 그들의 성역할이 반영되고 있는 것으로 나타났다. 또한, 여성 이용자들은 SNS를 정보이용이나 단순한 커뮤니케이션 수단으로 활용할 뿐, 자신의 의견제시 등의 참여에는 소극적 태도를 보임으로써 남성과는 달리 수동적인 이용행태를 보였다. 즉 여성들의 스마트폰 이용은 활발하지만, 콘텐츠의 선택이나 이용방식에 있어서는 성별화된 특성과 사회의 젠더가치가 재생산되고 있는 것으로 나타났다. 아울러 본 연구는 스마트폰이 일상화됨에 따라 우리생활에 어떤 변화를 가져오는지를 살펴본 것으로, 특히 스마트폰 강국으로 떠오르는 중국의 사례를 통해 앞으로 국내의 상황을 가늠해보는 중요한 단서를 제공한다고 할 수 있다.

• The Journal of Advanced Prosthodontics
• /
• 제3권2호
• /
• pp.69-75
• /
• 2011

This study assessed the effect of preparation design on marginal adaptation and also compared the sensitivity and specificity of clinical evaluation techniques for marginal accuracy of cast restorations to stereomicroscopy. MATERIALS AND METHODS. Three Ivorine molar teeth of different designs were prepared. (A)-A complete crown preparation with buccal shoulder and beveled finish line. (B)-A complete crown preparation with chamfer finish line. (C)-A three-quarter crown preparation with proximal boxes and beveled finish line. Twenty four castings were prepared with eight castings for each design respectively. Each casting underwent examination with an explorer, disclosing media, and a stereomicroscope. Stereomicroscopy at a value less than or equal to 30 microns was used as a gold standard to evaluate the significance of different designs on marginal adaptation. Chi-square tests of independence and Kruskal-Wallis were used to evaluate the effect of preparation design and compare the agreement between examination methods for detection of marginal gap size of greater than or equal to 30 microns (${\alpha}$=.05). Sensitivity and specificity for explorer and disclosing media as compared to stereomicroscope was calculated using statistical formula given by Park. RESULTS. The preparation design did not significantly affect overall marginal adaptation. Examination by explorer and disclosing media at $30 \;{mu}m$ revealed 39% and 10.06% sensitivity and 91% and 82% specificity respectively. CONCLUSION. Preparation designs examined in this study did not significantly affect the marginal adaptation of the castings. Commonly used clinical evaluation techniques using explorer and disclosing media appeared to be inadequate for assessment of marginal accuracy.

• 천문학논총
• /
• 제30권1호
• /
• pp.1-9
• /
• 2015

The National Foundation Day of Korea (개천절, 開天節) is currently celebrated on October 3 in Gregorian calendar. We review the history of dating the National Foundation Day of Korea and make a suggestion that it be celebrated on October 3 in the lunar calendar. We present numerous historical records on heaven-worship rites supporting the date October 3 in the lunar calendar. It is pointed out that October 3 in the solar calendar has been adopted in 1949 by the National Assembly with the thought that the lunar calendar is inferior and behind the times. The thought originates from misunderstanding on the value of the lunar calendar and from the ignorance of importance of history and tradition. Since there are now many national holidays that follow the lunar calendar, the logic of the National Assembly in 1949 also makes no sense. We emphasize that the lunar calendar should be followed for the National Foundation Day of Korea for its historical and symbolic characteristics restoration. We also investigate the year of the foundation of the first country of Korea, Dangun Joseon. It is found that even though the majority of the literature before late 15th century recorded the beginning year of Dangun Joseon dynasty to be equal to that of Liao Dynasty (堯), it was accidentally changed to the 25th year of Liao Dynasty in 1484 through a misinterpretation of the previous records. We claim that the beginning year of Dangun Joseon should be set to that of Liao Dynasty as recorded in the original literature in the earlier days. According to the two main opinions accepted by Korea, the beginning year of Liao Dynasty was 2357 B.C. or 2333 B.C., which correspond to the year of Gap-Jin (the 41st year of the sexagenary cycle) or Mu-Jin (the 4th year of the sexagenary cycle), respectively.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
• /
• pp.906-909
• /
• 2006

The secondary electron emission coefficient $({\gamma})$ of the cathode is an important factor for improving the discharge characteristics of AC-PDPs because of its close relationship to discharge voltage. In AC-PDPs, MgO is most widely used as a surface protective layer. In this experimental, we have investigated the electronic structure of the energy band structure of the MgO layer responsible for the high ${\gamma}$. The MgO layers have been deposited by electron beam evaporation method, where the $O_2$ partial pressures have been varied as 0, $5.2{\times}10^{-5}$ torr, $1.0{\times}10^{-4}$ torr, and $4.1{\times}10^{-4}$ torr, in this experiment. It is noted that work function that is energy gap between surface and first defect level of MgO layer has the lowest value for the highest O2 partial pressure of $4.1^{\ast}10^{-4}$ Torr.

• KIEAE Journal
• /
• 제16권3호
• /
• pp.121-128
• /
• 2016

Purpose: The vacuum glazing should constantly retain the gap in vacuum state to maintain high thermal performance. To do so, pillars are used to prevent the glazing from clinging to each other by the atmospheric pressure and therefore surface of the vacuum glazing is consistently affected by residual stress. The vacuum glazing could be applied to curtain wall systems at spandrel area to fulfill a rigorous domestic standard on U-value of the external wall. However, this can lead to high glazing temperature increase by heat concentration at a back panel and finally thermal stress breakage. This study experimentally determined weakness of the vacuum glazing systems on the thermal stress breakage and investigated effect of the residual stress. Method: The experiment first built two scale-down mock-up facilities that replicate the spandrel area in curtain wall, and then installed single low-e glass and vacuum glazing respectively. The two mock-up facilities were exposed to outside to induce the thermal stress breakage. Result: The experiment showed that the temperature occurred the thermal stress breakage was $114.4^{\circ}C$ for the single low-e glass and $118.9^{\circ}C$ for the vacuum glazing respectively. The result also showed the vacuum glazing reached the critical point earlier than the single low-e glass, which means that the vacuum glazing has high potential to occur the thermal shock breakage. In addition, the small temperature difference between two glazing indicates that the residual stress scarcely affects breakage of the vacuum glazing.