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Measuring the Third-Person Effects of Public Opinion Polls: Focusing On Online Polls (여론조사보도에 대한 제3자효과 검증: 온라인 여론조사를 주목하며)

  • Kim, Sung-Tae;Willnat, Las;Weaver, David
    • Korean journal of communication and information
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    • v.32
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    • pp.49-73
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    • 2006
  • During the past decades, public opinion polls have become an ubiquitous tool for probing the complexity of people's beliefs and attitudes on a wide variety of issues. Especially since the late 1970s, the use of polls by news organizations has increased dramatically. Along with the proliferation of traditional polls, in the past few years pollsters and news organizations have come to recognize the advantages of online polls. Increasingly there has been more effort to take the pulse of the public through the Internet. With the Internet's rapid growth during the past years, advocates of online polling often emphasize the relative advantages over traditional polls. Researchers from Harris Black International Ltd., for example, argue that "Internet polling is less expensive and faster and offers higher response rates than telephone surveys." Moreover, since many of the newer online polls draw respondents from large databases of registered Internet users, results of online polls have become more balanced. A series of Harris Black online polls conducted during the 1998 gubernatorial and senatorial elections, for example, has accurately projected the winners in 21 of the 22 races it tracked. Many researchers, however, severely criticize online polls for not being representative of the larger population. Despite the often enormous number of participants, Internet users who participate in online polls tend to be younger, better educated and more affluent than the general population. As Traugott pointed out, the people polled in Internet surveys are a "self selected" group, and thus "have volunteered to be part of the test sample, which could mean they are more comfortable with technology, more informed about news and events ... than Americans who aren't online." The fact that users of online polls are self selected and demographically very different from Americans who have no access to the Internet is likely to influence the estimates of what the majority of people think about social or political issues. One of the goals of this study is therefore to analyze whether people perceive traditional and online public opinion polls differently. While most people might not differentiate sufficiently between traditional random sample polls and non representative online polls, some audiences might perceive online polls as more useful and representative. Since most online polls allow some form of direct participation, mostly in the form of an instant vote by mouse click, and often present their findings based on huge numbers of respondents, consumers of these polls might perceive them as more accurate, representative or reliable than traditional random sample polls. If that is true, perceptions of public opinion in society could be significantly distorted for those who rely on or participate in online polls. In addition to investigating how people perceive random sample and online polls, this study focuses on the perceived impact of public opinion polls. Similar to these past studies, which focused on how public opinion polls can influence the perception of mass opinion, this study will analyze how people perceive the effects of polls on themselves and other people. This interest springs from prior studies of the "third person effect," which have found that people often tend to perceive that persuasive communications exert a stronger influence on others than on themselves. While most studies concerned with the political effects of public opinion polls show that exit polls and early reporting of election returns have only weak or no effects on the outcome of election campaigns, some empirical findings suggest that exposure to polls can move people's opinions both toward and away from perceived majority opinion. Thus, if people indeed believe that polls influence others more than themselves, perceptions of majority opinion could be significantly altered because people might anticipate that others will react more strongly to poll results.

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Effects of Phenolic and Phosphite Antioxidants on the properties for PC/ABS Blends during High-Shear-Rate Processing (고속 전단 가공에서 페놀계와 인산계 산화방지제에 의한 PC/ABS 블렌드의 물성 변화 연구)

  • Lee, Han Ki;Kim, Seon Hong;Lee, Hyung Il;Yoo, Jae Jung;Yong, Da Kyoung;Choi, Seok Jin;Lee, Seung Goo;Lee, Kee Yoon
    • Korean Chemical Engineering Research
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    • v.52 no.2
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    • pp.266-271
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    • 2014
  • The effects of antioxidants on the properties of Polycarbonate/Acrylonitrile-Butadiene-Styrene(PC/ABS) blends were studied for the functions of the screw speed and loaded duration of high shear rate processing in order to investigate the degradation for PC/ABS blends. Tris-(2,4-di-tert-butyl-phenyl phosphate) (A1) and Bis(2,4-dicumylphenyl) pentaerythritol diphosphite (A3) as phosphite antioxidants and Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (A2) as a phenolic antioxidant are used. The thermal properties were detected by TGA and severely decreased, after the processing. The stress-induced and thermal degradation for PC/ABS blends with the antioxidant A3 was retarded better than the others. By using UTM, the mechanical properties also showed individually decreased according to the antioxidants, after the processing, especially, the elongations showed considerable decline behaviors, while the tensile strengths of PC/ABS blends changed very little. For example, in the operating conditions of 1000rpm of screw speed and 20 seconds of loaded period, the elongations decreased from 148% before the processing, to 91.6% with the A1, to 63% with the A2 and to 131% with the A3 after the processing, respectively. In order to get the morphological properties, the size distributions of the dispersed phases for PC/ABS were investigated by SEM analysis and tended to decrease, as the screw speed and loaded period of the processing increased. Therefore, we confirmed that the antioxidant A3 was the best of all of three to inhibit the stress-induced degradation of PC/ABS blends during the high shear rate processing.

Flipped Learning in Socioscientific Issues Instruction: Its Impact on Middle School Students' Key Competencies and Character Development as Citizens (플립러닝 기반 SSI 수업이 중학생의 과학기술 사회 시민으로서의 역량 및 인성 함양에 미치는 효과)

  • Park, Donghwa;Ko, Yeonjoo;Lee, Hyunju
    • Journal of The Korean Association For Science Education
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    • v.38 no.4
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    • pp.467-480
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    • 2018
  • This study aims to investigate how flipped learning-based socioscientific issue instruction (FL-SSI instruction) affected middle school students' key competencies and character development. Traditional classrooms are constrained in terms of time and resources for exploring the issues and making decision on SSI. To address these concerns, we designed and implemented an SSI instruction adopting flipped learning. Seventy-three 8th graders participated in an SSI program on four topics for over 12 class periods. Two questionnaires were used as a main data source to measure students' key competencies and character development before and after the SSI instruction. In addition, student responses and shared experience from focus group interviews after the instruction were collected and analyzed. The results indicate that the students significantly improved their key competencies and experienced character development after the SSI instruction. The students presented statistically significant improvement in the key competencies (i.e., collaboration, information and technology, critical thinking and problem-solving, and communication skills) and in two out of three factors in character and values as global citizens (social and moral compassion, and socio-scientific accountability). Interview data supports the quantitative results indicating that SSI instruction with a flipped learning strategy provided students in-depth and rich learning opportunities. The students responded that watching web-based videos prior to class enabled them to deeply understand the issue and actively engage in discussion and debate once class began. Furthermore, the resulting gains in available class time deriving from a flipped learning approach allowed the students to examine the issue from diverse perspectives.

Effects of Korean Zingiber mioga R. (Flower Buds and Rhizome) Extract on Memory (한국산 양하(꽃봉오리와 지하경)의 인지 기능 개선 효과)

  • Cho, Kyo-Hee;Oh, Myung-Sook;Kim, Hyo-Geun;Lee, Sun-Hee;Chung, Kun-Sub;Kim, Ae-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.10
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    • pp.1519-1526
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    • 2014
  • This study investigated the biological activities and effects of Korean Zingiber mioga R. (flower buds and rhizome) on memory. The general composition, minerals, anti-oxidative activities, and AChE inhibitory effects were analyzed, and NORT (Novel object recognition test) and Y-Maze test in vivo were performed. The general contents (moisture, crude fat, crude protein, and crude ash; wet basis) of ZB (flower buds) were 91.96%, 0.15%, 1.99%, and 11.90%, respectively. The general contents (moisture, crude fat, crude protein, and crude ash; wet basis) of ZR (rhizome) were 75.21%, 0.53%, 2.20%, and 9.50%, respectively. The macro mineral contents (Ca, P, Na, and K) of ZB were 31.70 mg%, 15.20 mg%, 8.20 mg%, and 258.60 mg%, respectively. Inhibitory effects (IC50 value) of DPPH and ABTS radicals were higher with ZBD (flower buds water extract) than with ZBE (flower buds EtOH extract), ZRD (rhizome water extract) or ZRE (rhizome EtOH extract). AChE inhibitory effect of ZBD was higher and that of ZRD. NORT and Y-Maze test were performed with scopolamine-induced mice treated with ZBD and ZBE. In NORT, effects of ZBD and ZBE were similar to that of donepezil. In the Y-maze test, performances of ZBD and ZBE-treated mice were similar to that of the normal group. These results suggest that Korean Zingiber mioga R. has potential to be developed into a new functional food for cognition enhancement in the global food market.

Identification of Pre-pasteurization or Pre-irradiation Treatment in Frozen Crushed Garlic Commercially Available in Korean Market (시판 유통 중인 냉동 다진 마늘의 사전 살균 및 조사처리 여부 판별 모니터링)

  • Kim, Hyo-Young;Ahn, Jae-Jun;Kim, Gui-Ran;Jeong, Jin-Hwa;Park, Ki-Hwan;Kwon, Joong-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1673-1681
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    • 2013
  • Five different chopped frozen garlic products samples, three from Chinese and two from Korean origins being commercially available products in Korean market, were used to confirm their pre-pasteurization or pre-irradiation status by screening (direct epifluorescent filter technique/aerobic plate counts, DEFT/APC; electronic nose, E-nose; photostimulated luminescence, PSL) and identification (thermoluminescence, TL; electron spin resonance, ESR) techniques. Some parts of samples were gamma-irradiated at 1 kGy to be used as control samples in irradiation history identification. DEFT/APC and e-nose successfully showed distinct results between the domestic and imported samples. The PSL photon counts of all the unknown samples were less than 700 (negative), while most of 1 kGy-irradiated samples gave PSL photon counts more than 5,000 (positive). The domestic unknown samples produced the TL glow peaks after $300^{\circ}C$ or more, whereas the imported samples showed TL peaks at the range of $240{\sim}250^{\circ}C$. A clear TL glow peak was obtained from all irradiated samples at $150{\sim}250^{\circ}C$. The unknown samples of Chinese origin gave radiation-specific cellulose ESR signal that was not shown by domestic samples. A multiple step of applying the physical analytical methods is recommended for the effective identification of irradiation status on chopped frozen garlic products.

Effect of LED Light Wavelength on Lettuce Growth, Vitamin C and Anthocyanin Contents (LED광 파장이 상추생육과 비타민 C 및 안토시아닌 함량에 미치는 영향)

  • Choi, Man Kwon;Baek, Gyeong Yun;Kwon, Soon Joo;Yoon, Yong Cheol;Kim, Hyeon Tae
    • Journal of Bio-Environment Control
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    • v.23 no.1
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    • pp.19-25
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    • 2014
  • In this study, we analyzed the growth characteristics of red lettuce under Light-emitting diode (LED) light environment as well as the change of vitamin C and anthocyanins of lettuce. We made five monochromatic light treatments (red 647 nm, 622 nm, blue 463 nm, 450 nm, White), six mixed red (R) and blue (B) light treatments (R : B = 9 : 1, 8 : 2, 7 : 3, 6 : 4, 5 : 5) and red + white, and three light treatments made according to photoperiod of LED with lighting sources ratio of red : blue (R : B = 8 : 2(18/06 h, 15/09 h, 12/12 h)). It was composed of totally 14 control beds. As a result, the red lettuce the most developed leaf height, leaf numbers and fresh weight under red single light, root length and leaf developed when grown under blue single light. Therefore, red light were related to above part of the lettuce, blue light were related to the growth of the underground part of lettuce. Case of the mixed light, leaf height, leaf numbers, fresh/dry weight of above and underground part were highest red + white light and root length and chlorophyll content were highest under red 7 : 3 blue light. Result of growing investigation by photoperiod, the red lettuce were considered to be most effective in 15/09 h (on/off). The content of anthocyanins; the single light source, mixed light and light irradiation period were highest under blue light (463 nm), red 7 : 3 blue and 18/06 h (on/off) light irradiation, respectively. The vitamin C showed the lowest content of $1.26mg{\cdot}L^{-1}$ under the white light, but showed the greatest content of $3.02mg{\cdot}L^{-1}$ for the control group.

Pupal Drone Extracts for Anti-wrinkle and Skin-lightening Materials (수벌번데기 추출물의 주름개선 및 미백효과 구명)

  • Kim, Jung-Eun;Kim, Do-Ik;Koo, Hui-Yeon;Kim, Hyeon-Jin;Kim, Seong-Yeon;Lee, Yoo-Beom;Moon, Jae-Hak;Choi, Yong-Soo
    • Journal of Life Science
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    • v.30 no.5
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    • pp.428-433
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    • 2020
  • In this study, we created pupal stage extracts of Apis mellifera L. drones for use in cosmetic materials. The effect of the drone pupae extract (DPE) on HDF cells was assessed for analysis of anti-wrinkle activity by collagen or collagenase gene expression, and the skin-lightening effect was studied by in vitro tyrosinase inhibition and B16F10 melanoma assay; the two cells were found to be non-cellular when the concentration of DPE was 100 ㎍/ml. Albutin concentration (positive control) in the whitening test was set at a capacity of 100 ug/ml and m-melanocyte stimulating hormone (α-MSH). A melanin-producing induction material was set at a concentration of 100 nM, and the expression of collagen type I and MMP1 collagenase was measured using HDF cells. MMP1 expression was seen to reduce in a concentration-dependent manner in treatment with DPE. Inhibiting melanin generation with B16F12 cells indicated a tendency to decrease in the DPE treatment group. Both L-Tyrosine and L-DOPA as DPE were used in an in vitro tyrosinase induction test to demonstrate the effects of tyrosinase suppression on concentrations. The higher the concentration of DPE, the greater the wrinkle reduction and whitening effect. In conclusion, it was found that DPE is an effective smoothing and whitening material by increasing collagen generation and inhibiting collagenase expression and reducing melanin production.

An Empirical Study on How the Moderating Effects of Individual Cultural Characteristics towards a Specific Target Affects User Experience: Based on the Survey Results of Four Types of Digital Device Users in the US, Germany, and Russia (특정 대상에 대한 개인 수준의 문화적 성향이 사용자 경험에 미치는 조절효과에 대한 실증적 연구: 미국, 독일, 러시아의 4개 디지털 기기 사용자를 대상으로)

  • Lee, In-Seong;Choi, Gi-Woong;Kim, So-Lyung;Lee, Ki-Ho;Kim, Jin-Woo
    • Asia pacific journal of information systems
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    • v.19 no.1
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    • pp.113-145
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    • 2009
  • Recently, due to the globalization of the IT(Information Technology) market, devices and systems designed in one country are used in other countries as well. This phenomenon is becoming the key factor for increased interest on cross-cultural, or cross-national, research within the IT area. However, as the IT market is becoming bigger and more globalized, a great number of IT practitioners are having difficulty in designing and developing devices or systems which can provide optimal experience. This is because not only tangible factors such as language and a country's economic or industrial power affect the user experience of a certain device or system but also invisible and intangible factors as well. Among such invisible and intangible factors, the cultural characteristics of users from different countries may affect the user experience of certain devices or systems because cultural characteristics affect how they understand and interpret the devices or systems. In other words, when users evaluate the quality of overall user experience, the cultural characteristics of each user act as a perceptual lens that leads the user to focus on a certain elements of experience. Therefore, there is a need within the IT field to consider cultural characteristics when designing or developing certain devices or systems and plan a strategy for localization. In such an environment, existing IS studies identify the culture with the country, emphasize the importance of culture in a national level perspective, and hypothesize that users within the same country have same cultural characteristics. Under such assumptions, these studies focus on the moderating effects of cultural characteristics on a national level within a certain theoretical framework. This has already been suggested by cross-cultural studies conducted by scholars such as Hofstede(1980) in providing numerical research results and measurement items for cultural characteristics and using such results or items as they increase the efficiency of studies. However, such national level culture has its limitations in forecasting and explaining individual-level behaviors such as voluntary device or system usage. This is because individual cultural characteristics are the outcome of not only the national culture but also the culture of a race, company, local area, family, and other groups that are formulated through interaction within the group. Therefore, national or nationally dominant cultural characteristics may have its limitations in forecasting and explaining the cultural characteristics of an individual. Moreover, past studies in psychology suggest a possibility that there exist different cultural characteristics within a single individual depending on the subject being measured or its context. For example, in relation to individual vs. collective characteristics, which is one of the major cultural characteristics, an individual may show collectivistic characteristics when he or she is with family or friends but show individualistic characteristics in his or her workplace. Therefore, this study acknowledged such limitations of past studies and conducted a research within the framework of 'theoretically integrated model of user satisfaction and emotional attachment', which was developed through a former study, on how the effects of different experience elements on emotional attachment or user satisfaction are differentiated depending on the individual cultural characteristics related to a system or device usage. In order to do this, this study hypothesized the moderating effects of four cultural dimensions (uncertainty avoidance, individualism vs, collectivism, masculinity vs. femininity, and power distance) as suggested by Hofstede(1980) within the theoretically integrated model of emotional attachment and user satisfaction. Statistical tests were then implemented on these moderating effects through conducting surveys with users of four digital devices (mobile phone, MP3 player, LCD TV, and refrigerator) in three countries (US, Germany, and Russia). In order to explain and forecast the behavior of personal device or system users, individual cultural characteristics must be measured, and depending on the target device or system, measurements must be measured independently. Through this suggestion, this study hopes to provide new and useful perspectives for future IS research.

Structure and Variation of Tidal Flat Temperature in Gomso Bay, West Coast of Korea (서해안 곰소만 갯벌 온도의 구조 및 변화)

  • Lee, Sang-Ho;Cho, Yang-Ki;You, Kwang-Woo;Kim, Young-Gon;Choi, Hyun-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.100-112
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    • 2005
  • Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

Characteristics of Bunsen Reaction using Ultrasonic Irradiation in Sulfur-iodine Hydrogen Production Process (황-요오드 수소 제조 공정에서 초음파 조사를 이용한 분젠 반응의 특성)

  • Kim, Hyo Sub;Lee, Dong Hee;Lee, Jong Gyu;Park, Chu Sik;Kim, Young Ho
    • Applied Chemistry for Engineering
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    • v.29 no.1
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    • pp.56-61
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    • 2018
  • In Bunsen reaction section for the integrated operation of sulfur-iodine (SI) process, $I_2$ and $H_2O$ reactants are supplied as dissolved species in an $HI_x$ solution. Most of the $H_2SO_4$ product is found in the $HI_x$ phase when Bunsen reaction is performed using the $HI_x$ solution and $SO_2$ feed, so that the volume ratio of the $H_2SO_4$ phase to the $HI_x$ phase is very low. In this study, we investigated the effects of ultrasound irradiation on Bunsen reaction using the $HI_x$ solution to improve its phase separation performance. With ultrasound irradiation, the amount of $H_2SO_4$ moved to the $H_2SO_4$ phase from the $HI_x$ phase increased by up to 58.0 mol% and the volume of $H_2SO_4$ phase also increased by up to 13.1 vol%. In particular, the effect of ultrasound irradiation on the phase separation was improved with decreasing operating temperature, $I_2$ and $H_2O$ feed concentrations. The ultrasound irradiation induces the formation of additional $H_2O$ molecules by shifting microscopically the reaction equilibrium in the $HI_x$ phase. Afterward, the additionally generated $H_2O$ and isolated $H_2SO_4$ molecules form more $H_2SO_4{\cdot}xH_2O$ (x = 5-6) clusters that can be moved to the $H_2SO_4$ phase.