• 한국노년학
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• v.38 no.3
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• pp.593-605
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• 2018

This study examines factors that influence older drivers to consider stopping driving in advance and whose advice plays an important role in the driving cessation decision. Data came from a nationally representative cross-sectional survey of community-dwelling older adults (N=2,076). About two thirds reported that they have considered stopping driving (62.8%) and they preferred to decide by themselves (66.0%). Logistic regression results showed that women and residents in urban areas were twice as likely to consider voluntary driving cessation compared to their counterparts. Each one year increase in age contributed to the probability that respondents would consider driving cessation by five percent. Those with greater difficulties in ADLs due to chronic illnesses were also more likely to consider driving cessation. No sociodemographic and health factors were related to whether older drivers preferred to decide by themselves or listen to others. These results imply that policies to promote self-motivation to stop driving among older drivers would be effective. Furthermore, they suggest it could be important to help older drivers plan their driving cessation in advance while still at a young-old age, and that more attention needs to be paid to men and those living in rural areas among older drivers.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.245-251
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• 2007

The performance of fuel cell is enhanced with increasing reaction surface. Narrow flow channels in flow plate cause increased pumping power. Therefore it is very important to consider the pressure drops in the flow channel of fuel cell. Previous research for pressure drop for micro channel of fuel cell was focused on effects of various configuration of flow channel without electrochemical reaction. It is very important to know pressure loss of micro flow channel with electrochemical reaction because fluid density in micro channel is changed due to chemical reaction. In this paper, it is investigated that the pressure drops in micro channel of various geometries at anode and cathode with electrochemical reaction and compared them to friction coefficient (fRe), velocity, pressure losses for corresponding non reacting flow channel. The results show that friction factors for cold flow channel could be used for parallel and bended flow channel for flow channel design of fuel cell. In the other hand, pressure drop for serpentine flow channel is the lowest among flow channels due to bypass flow across gas diffusion layer under reacting flow condition although its pressure drop is highest for cold flow condition.

• Journal of the Korean Electrochemical Society
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• v.18 no.4
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• pp.143-149
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• 2015

Carbon-coated $Li_2MnSiO_4$ powders as the active materials for the cathode were synthesized by planetary ball milling and solid-state reaction, and their phase formation behavior and charge-discharge properties were investigated. Calcination temperature and atmosphere were controlled in order to obtain the ${\beta}-Li_2MnSiO_4$ phase, which was active electrochemically, and the carbon-coated $Li_2MnSiO_4$ active material powders with near single phase ${\beta}-Li_2MnSiO_4$ could be fabricated. The particles of the synthesized powders were secondary particles composed of primary ones of about 100 nm size. The carbon incorporation was essential to enable the Li ions to be inserted and extracted from $Li_2MnSiO_4$ active materials, and the initial capacity of 192 mAh/g could be obtained in the $Li_2MnSiO_4$ active materials with 4.8 wt% of carbon.

• Environmental and Resource Economics Review
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• v.27 no.1
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• pp.139-160
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• 2018

Using survey data of selected 1,349 individuals nationwide in Korea, we measure the influencing factors for the acceptance of nuclear power and estimates the probability of acceptance under several scenarios with different percentages of monetary compensation. Results of panel probit demonstrate that nuclear risk aversion tendency was found to be higher in case of female, younger age, past experience of extreme event such as an earthquake. However, the residents' residency nearby the nuclear power plant was not related to the risk-aversion tendency. In addition, we found that the nuclear acceptance is improved when the monetary compensation rate is increased. Although the policy demand intended to reduce GHG emissions in South Korea, the expansion of nuclear power is not be easy due to the occurrence of recent strong earthquakes because the risk attitude of an individual is influenced by subjective assessments formed through direct and indirect experiences of natural disasters such as an earthquake. Our results suggest that the opposition to construction of nuclear power plant is expected to be further intensified especially when combined with the experiences of threatening earthquakes. As a result, the debate and policy conflicts of nuclear power plants will consistently continue and large social costs are apparent for the acceptance of nuclear power plant.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.685-698
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• 2010

Acrolein is a highly toxic, reactive mutagenic aldehyde. Humans are exposed to acrolein vapors from overheated cooking oil, cigarette smoke, and combustion of organic products. In this study, we investigated elementary and middle school students' consumption of foods cooked at high heat, such as fried, direct fire, and indirect fire cooked foods. The subjects of this survey study were 265 fifth grade students and 396 middle school students nationwide. According to the results of the frequency test, broiled fish was the most frequently consumed, followed by fried fish, indirect cooked samgyebsal, and other fried foods, which were eaten more than three times per month. The total intake of foods cooked at high heat per child over 1 year was in the following order: Fried chicken(7.50 kg) > Samgeybsal(6.57 kg) > Broiled pork ribs(4.18 kg) > Broiled fish(4.12 kg) > Bulgogi(3.31 kg) > Fried dish(3.18 kg) > Pork cuttlet(3.17 kg) > Jeyukbockeum(3.13 kg) > Charcoal-broiled beef ribs(2.74 kg) > Roasted whole chicken(2.05 kg) > Dackochi(1.87 kg) > Tangsuyuk(1.87 kg) > Fried fish(1.83 kg) > Hamburger patties(1.21 kg) > Fried potato(1.01 kg) > Barbecue(0.95 kg) > Doughnut(0.80 kg) > Corn dog(0.66 kg) > Croquette(0.51 kg). The favorite cooking method was indirect fire cooking for beef, pork, and fish, whereas frying was preferred for chicken. The results of this study provide important data for assessment of acrolein exposure via foods cooked at high heat temperature. The results also indicate that children might be exposed to acrolein through consumption of foods cooked at high heat temperature, suggesting the need to promote education of proper food consumption behavior.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.3
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• pp.37-41
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• 2012

The wafer level stacking with Cu-to-Cu bonding becomes an important technology for high density DRAM stacking, high performance logic stacking, or heterogeneous chip stacking. Cu CMP becomes one of key processes to be developed for optimized Cu bonding process. For the ultra low-k dielectrics used in the advanced logic applications, Ti barrier has been preferred due to its good compatibility with porous ultra low-K dielectrics. But since Ti is electrochemically reactive to Cu CMP slurries, it leads to a new challenge to Cu CMP. In this study Ti barrier/Cu interconnection structure has been investigated for the wafer level 3D integration. Cu CMP wafers have been fabricated by a damascene process and two types of slurry were compared. The slurry selectivity to $SiO_2$ and Ti and removal rate were measured. The effect of metal line width and metal density were evaluated.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.256-256
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• 2015

이산화 바나듐 ($VO_2$)은 340 K 임계온도를 기점으로 금속-절연체 상전이를 통해 전기적, 광학적 특성이 가역적으로 변하는 물질로 잘 알려져 있다. 그러나 낮은 가시광 투과율과 비선호적인 색상(황갈색)으로 인해 열변색 스마트 창호응용과 관련하여 해결해야 할 문제로 남아있다. 본 연구에서는 상기 문제를 해결하고자 고분자 나노 구 템플릿을 응용하여 2차원의 벌집구조를 갖는 $VO_2$ 박막을 졸 겔 방법을 통해 제작하였으며 가시광 투과율 향상을 유도하였다. 나노 구의 지름과 코팅조건에 따라 구조변화를 유도하였으며 FE-SEM과 AFM을 통해 박막의 구조적 변화를 측정하였다. 결과로부터 나노 구의 역상모양을 갖는 박막이 형성 되었으며 직경에 따라 패턴 간격이 확연하게 변화되었음을 확인 하였다. 나노 구가 위치하고 있던 자리로부터 빈 공간형성을 유도할 수 있었으며 이는 가시광 투과율향상에 직접적 영향을 주었다. 또한 상기 패턴화된 $VO_2$ 박막은 광학 스위칭 효율을 유지하면서 주기적 패턴으로부터 시각적으로 광결정유도를 통한 미적 시너지를 보였며 본 연구로부터 $VO_2$기반 스마트 창호 응용에 많은 기여가 기대된다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.418-418
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• 2004

풀, 토양 또는 지하수와 같은 환경시료 중에 포함된 미량 우라늄을 분석하기 위하여 핵분열 트랙 기입법을 이용하였다. 시료 전처리 방법으로 지하수 시료는 질산 산성으로 만든 후, 토양시료는 질산과 불산을 이용하여 용액화 하였으며, 풀 시료는 전기로를 이용하여 회화한 후, 질산과 불산을 이용하여 용액화 하였다. 이 환경시료 전처리용액들을 각각 0.1mL를 0.9mL Collodion 분산용액에 섞은 후, 우라늄 표준용액과 함께 플라스틱 판($6{\times}6\textrm{cm}^2$) 위에 10$\mu\textrm{\ell}$씩 점적, 건고 시키고 핵분열 트랙기입법을 이용하여 우라늄 농도를 분석하였다. 핵분열 트랙기입법을 위한 중성자조사는 한국원자력연구소 하나로 연구용원자로(열중성자 선속: $2.7{\times}10^{13}n/\textrm{cm}^2{\cdot}sec^{-1}$)에서 10분간 하였으며, 6.25M NaOH 용액($60^{\circ}C$)을 이용하여 10분간 화학 에칭 하였다. 고체트랙검출기 표면에 생성된 핵분열 트랙들은 광학현미경과 image analyzer system을 이용하여 관찰하고 계수하였다. 시료와 같이 점적한 우라늄 표준용액을 이용하여 우라늄 농도에 대한 단위면적당 트랙 수의 상관관계를 구하였으며, 이를 이용하여 시료 내 우라늄 농도를 결정하였다. 본 실험의 결과에 대한 검증을 위하여 동일 시료용액을 분리관을 이용한 전처리 과정을 거친 후 ICP-MS를 이용하여 분석하였다. 우라늄의 선택적 분리를 위하여 U-TEVA 추출크로마토그래피 분리관을 이용하였다. 본 연구의 핵분열 트랙기입법을 이용하여 환경시료를 분석하는 방법은 일반적인 분광법을 이용할 경우, 문제가 되는 방해 원소의 분리를 위한 전처리 과정이 불필요한 장점을 가지고 있으며, 1ng 정도의 미량 우라늄을 분석할 수 있었고, ICP-MS 결과와 20% 오차 이내에서 일치하였다.

• Journal of Korean Library and Information Science Society
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• v.43 no.4
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• pp.47-68
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• 2012

The purpose of this study is to understand the direction of 'One Book, One City' community reading campaign by analyzing the characteristics of selected books, including their classification numbers, subject headings, publication dates, and genres. An analysis of lists of 'One Book, One City' Reading Promotions Projects' available from the website of the Library of Congress, the Center for the Books, and bibliographic records of 210 books from LC OPAC, shows the preference for the recently published American literatures in the genre of Bildungsromane and domestic fiction which describe the life of people with multi-cultural or ethnic backgrounds. It is confirmed that 'One Book, One City' community reading campaign has been consistently oriented to achieve the understanding and integration of a community by reading and discussion of one book.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.118-127
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• 2013

The purpose of this study was to know about the influence of consumers' knowledge level(expert vs novice) on their behavioral intentions by the storytelling about local foods. Reviewing previous storytelling studies related to local foods containing each region's traditional food culture in Korea, it can identify that most studies focused on the necessity of storytelling, the discovery of story materials, the importance of storytelling for food tour. Therefore, this study tried to know about how the storytelling about local foods influenced on the consumers' behavioral intentions, and set the attributes of storytelling and the consumers' local food-purchasing region as adjustable variances. Finally, in case that the consumers' knowledge level was low and their food-purchasing regions were not same, this study suggested the attributes of most preferred storytelling by consumers. By doing so, this study tried to discover the storytelling skills of local foods representing each region or to suggest a method to increase the cultural values of each local food in case of creating a story about the local food.