• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.120-120
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• 2011

Graphene is a carbon based material and it has great potential of being utilized in various fields such as electronics, optics, and mechanics. In order to develop graphene-based logic systems, graphene field-effect transistor (GFET) has been extensively explored. GFET requires supporting devices, such as volatile memory, to function in an embedded logic system. As far as we understand, graphene has not been studied for volatile memory application, although several graphene non-volatile memories (GNVMs) have been reported. However, we think that these GNVM are unable to serve the logic system properly due to the very slow program/read speed. In this study, a GVM based on the GFET structure and using an engineered graphene channel is proposed. By manipulating the deposition condition, charge traps are introduced to graphene channel, which store charges temporarily, so as to enable volatile data storage for GFET. The proposed GVM shows satisfying performance in fast program/erase (P/E) and read speed. Moreover, this GVM has good compatibility with GFET in device fabrication process. This GVM can be designed to be dynamic random access memory (DRAM) in serving the logic systems application. We demonstrated GVM with the structure of FET. By manipulating the graphene synthesis process, we could engineer the charge trap density of graphene layer. In the range that our measurement system can support, we achieved a high performance of GVM in refresh (>10 ${\mu}s$) and retention time (~100 s). Because of high speed, when compared with other graphene based memory devices, GVM proposed in this study can be a strong contender for future electrical system applications.

• Journal of the Korean association of regional geographers
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• v.21 no.2
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• pp.379-393
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• 2015

The fire damage has been increased as the frequency of fire incidence decreases with increasing in death and economic loss. Local governments are dependent on the activities of fire-fighters with crude preparedness and prevention for fire incidence. Most of researches on fire safety have focused on descriptive statistics which show general trends in fire incidence and condition. Here we tried to make a mutual causal model for fire damage, to make three big hypotheses with laying three small hypotheses under each big hypothesis. Five years statistics from public domains in the form of hardcopy or softcopy were collected and fifteen independent variables were selected to explain the number of death, the number of fire incidence and the amount of economic loss from fire incidence. The significances of statistics are different among the regional characteristics. The hypotheses were partially rejected and the meanings of rejected factors will refresh the tentative prejudice. It is necessary to revise the principle that the number of population and size of area are regarded as the most important criteria to allocate resources for fire control and to have the criteria flexible with results of our research such as the number of the weak to fire disaster.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1245-1252
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• 2003

A starter formulation was developed to substitute a baker's yeast with natural starter when manufacturing bread products. To develop an active starlet, starter was formulated varying with types of wheat flours, level of water contents and various nutrients. Activities of starter were investigated in terms of viable counts of microbes and change of pH and total titratible acidity Domestic wheat flours contain 100 times more number of lactic acid bacteria than yeast regardless of types of wheat flours. The more protein contents in wheat flours, the more stable microbes in starter. This was considered to be the result of buffering effect of wheat proteins. The optimum level of protein content to ensure the activity of starter was more than 12.0%. Optimum level of water content in active starter was 110% based on strong flour. The more water or the less water had the tendency of decreasing viable counts of microbes. Addition of salt and sucrose had increased the activity of starters. However oligosaccharides did not affect the activity of starter. The optimum concentrations of salt and sucrose were 1.0% and 5.0% respectively. Bread with the starter was higher scored than breads with yeast in terms of all the quality and sensory characteristics except their volumes. In conclusion, a starter formulated with strong flour 100%, water 110%, salt 1% and sucrose 5% was considered to have high potential as a substitute of yeast in making natural bread.

• East Asian mathematical journal
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• v.28 no.4
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• pp.383-401
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• 2012

The purpose of mathematics education includes two important areas; cognitive area that emphasizes mathematical knowledge and understanding and affective area that stresses mathematical interest and attitude. The purpose of mathematics education is not only in acquiring the contents and knowledge but also rousing up interest and attention toward mathematics. Therefore, effort to accomplish this affective purpose has to be made. Introducing history of mathematics to teaching can be a important method for the students to arouse interest and attention toward mathematics. History of mathematics can help the students who are familiar to only manipulation of the symbols to develop a new way of thinking and mathematical thoughts arousing reflective thinking. According to the survey, although the effect of using mathematics history has been recognized, the mathematics history has neither been developed as teaching materials nor reflected in the courses of study. The purpose of this research is to develop the reading materials into suit for the mathematics curriculum to extract contents of the mathematics valuable in using in elementary mathematics teaching, and to investigate the effect of reading materials using the history of mathematics on learning attitude in elementary school. The way of developing materials in this study is as follows. First, to select the interesting and instructive subject for the elementary students such as the story and life of a mathematician, developmental stages of mathematical theory and calculation currently used and finding the patterns of the rules that requires mathematical thoughts. Second, to classify the selected items according to mathematics curriculum. Third, to reorganize the classified items of the appropriate grade with the reading materials of dialogue pattern in order to draw attention and interest from the students I developed 18 kinds materials in accordance with the above procedure and applied 5 materials among them to one class in 4th grade. Analysing the student's responses, First, using history of mathematics helps the students to arouse interest and confidence on mathematical learning attitude. And the students became better attitude of studying by oneself and attention on class. Second, as know by opinions after lesson, most students have a chance refresh one's thinking of mathematics, want to know the other content of history of mathematics and responded to study hard in mathematics. As a result, the reading materials on the basis of the history of mathematics motivates students for mathematics and helps them become confident in mathematics. If the materials are complemented properly, they will be useful and effective for students and teachers.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.645-654
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• 2019

The purpose of this study was to analyze the current status of and necessity for forest education in Korea in order to promote educational programs on the topic among different age groups. A survey conducted among 1,542 adults nationwide indicated that different age groups had variable degrees of awareness and experience of forest education programs. Specifically, older people responded more positively in terms of awareness, experience, and willingness to engage with forest education programs, and engaging in individual holistic development. In addition, participant companion types and motivation for participating in forest education programs were different among age groups. Regarding motivation for participating in forest education programs, all groups answered, "to enjoy the forest landscape," "to experience new things," and "to refresh themselves." In particular, individuals in their 30s had a desire to learn, while those in their 50s had a desire for a healthy lifestyle. Additionally, people in their 40s showed the highest participation rate in forest education programs, alongside their children and family members. In terms of operating period, older individuals preferred long-term operating programs. Accessibility was the most important factor for all age groups when selecting forest education programs. We hope that this study will be useful for the development and promotion of forest education programs for all age groups.

• KIPS Transactions on Software and Data Engineering
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• v.1 no.1
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• pp.1-6
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• 2012

Web pages in a template-based web application (TWA) are automatically populated using a template shared by the pages with contents specific to the pages. So users can easily obtain information guided by a consistent structure of the template. Reduced duplicated code helps to increase the level of maintainability as well. However, TWA still has the interaction problem of classic web applications that each time a user clicks a hyperlink a new page is loaded, although a partial update of the page is desirable. This paper proposes a reengineering technique to transform the multi-page structure of legacy Java-based TWA to a single page one with partial page refresh. In this approach, hyperlinks in HTML code are refactored to AJAX-enabled event handlers to achieve the single page structure. In addition, JSP and Servlet code is transformed in order not to send data unnecessary for the partial update. The new single page consists of individual components that are updateable independently when interacting with a user. Therefore, our approach can improve interactivity and responsiveness towards a user while reducing CPU and network usage. The measurement of our technique applied to a typical TWA shows that our technique improves the response time of user requests over the TWA in the range from 1 to 87%.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.62-70
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• 2015

Recently the demand for projected capacitance touch screens is sharply growing especially for large screens for medical devices, PC monitors and TVs. Large touch screens in general need a controller of higher complexity. They usually have a larger number of driving and sensing lines, and hence it takes longer to scan one frame for touch detection leading to a low frame scan rate. In this paper, a novel touch screen control technique is presented, which scans each frame in two steps of simultaneous multi-channel driving. The first step is to drive all driving lines simultaneously and determine which sensing lines have any touch. The second step is to sequentially rescan only the touched sensing lines, and determine exact positions of the touches. This technique can substantially increase the frame scan rate. This technique has been implemented using an FPGA and an AFE board, and tested using a commercial 23-inch touch screen panel. Experimental results show that the proposed technique improves the frame scan rate by 8.4 times for the 23-inch touch screen panel over conventional methods.

• Journal of IKEEE
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• v.27 no.4
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• pp.644-649
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• 2023

As the cell spacing decreases during the scaling process of DRAM(Dynamic Random Access Memory), the reduction in STI(Shallow Trench Isolation) thickness leads to an increase in sub-threshold leakage due to the passing word line effect. The increase in sub-threshold leakage current caused by the voltage applied to adjacent passing word lines affects the data retention time and increases the number of refresh operations, thereby contributing to higher power consumption in DRAM. In this paper, we identify the causes of the passing word line effect through TCAD Simulation. As a result, we confirm the DRAM operational conditions under which the passing word line effect occurs, and observe that this effect alters the proportion of the total leakage current attributable to different causes. Through this, we recognize the necessity to consider not only leakage currents due to GIDL(Gate Induced Drain Leakage) but also sub-threshold leakage currents, providing guidance for improving DRAM structure.

• Journal of Korean Home Economics Education Association
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• v.26 no.4
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• pp.21-34
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• 2014

This study examined the levels of recognition, knowledge, and intake behavior of foods containing caffeine and analyzed the factors affecting amount of caffeine intake to get basic materials for development of educational program for proper intake behavior of foods containing caffeine of high school students in Gyeongbuk region. Of 300 questionnaires that were distributed on December 27, 2013 to February 14, 2014, 255 responses were used for analysis. Frequency distributions, Cronbach's ${\alpha}$, t tests, one-way ANOVA, Pearson's correlation analysis, and regression analysis were conducted by SPSS Windows V.21.0. The mean of the level of concern about foods containing caffeine was 2.76/5.00 points; male and second and third grade students showed lower concern level than female and first grade students. The respondents answered that intake of foods containing caffeine had somewhat harmful effect on health, but it did not much help to refresh and increase concentration. The mean for the percentage of correct answers about knowledge of caffeine was 54.3. Small number of the respondents were advised to reduce intake of caffeine from school teachers or parents. The average of caffeine intake amount was 71.67mg/day; the average for male was 78.98mg/day, whereas for female 61.23mg/day. Almost thirteen percentage of the respondents took caffeine over RDA(Recommended Daily Allowance). According to the result of regression analysis for amount of caffeine intake, grade, BMI, concern about health, perception of whether foods containing caffeine help with refreshment and increase of concentration or not, and experiences of having advice from school teachers to decrease caffeine intake were significant. These results imply that it is necessary for high school students to educate how to take caffeine properly.

• Journal of the Korean Society of Food Culture
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• v.8 no.1
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• pp.21-42
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• 1993

To understand the dietary culture in Poongki region which was established as Kamrokchon of a folk community, the transmission pattern of the traditional dietary life was investigated by questionnaire to 383 housewives, and the results are as follows : 1) Daily diet : Among 65 traditional main dishes of 6 areas including Kyungsangdo, D’cokguk of Kyungsangdo was consumed most frequently, 87%. General consumption rate based on origin of food was 33.3% of Kyungsangdo, 21.2% of Chungchongdo, 13.1% of Kangwondo, 11.9% of Hwanghaedo, 1.1% of Pyungando and Hamkyungdo, respectively. Among 243 traditional minor dishes, Doenjangjjigye and Kochuchang of Kyungsangdo were most consumed as rates of 91.6%, 89.3%, respectively. General consumption rate based on origin was in order of 38.4% of Kyungsangdo, 19.3% of Chungchongdo, 14.9% of Kwangwondo, 10.4% of Hamkyungdo, 8.7% of Hwanghaedo and 8.3% of Pyungando. 2) Special diet : Among 66 traditional D’ocks, Injeolmi of Hamkyungd was consumed most freguently, 58%. General consumption rate based on origin was in order of 26.3% of Hwanghaedo, 17.6% of Kyungsangdo, 16.1% of Kwangwondo, 16.0% of Hamkyungdo, 13.0% of Pyungando and 11.0% of Chungchongdo. Among 27 cookies, Kangjeong of Hamkyungdo was consumed most frequently 46.7%. General consumption rates based on origin was in order of 55.7% of Hamkyungdo, 22.7% of Kyungsangdo, 2.4% of Pyungando, 5.8% of Kwangwondo, 3.0% of Chungchongdo and 0.4% of Hwanghaedo. Among 19 refresh drinks, Kamju of Kyungsangdo was consumed most frequently, 76.0%. General consumption rate based on origin was in order of 74.3% of Kyungsangdo, 7.8% of Chungchongdo, 6.9% of Hamkyungdo, 5.9% of Hwanghaedo and 5.1% of Kwangwondo. 3) Ceremonial diet : Myyeogguk and Baeksulgi for the 100-Days ceremony and Hynbab and Baeksulgi for the First Birthday were used mainly. For birthday, noodle(59.5%) for lunch besides rice as main dish and Soojeoggwa(37.9%) were served and noodle(30.8%) was used for host. Thirty percent of the varieties used traditionally for Pyehak and 40-50% of the varieties for Jesa(Memorial day) are still prepared currently. 4) Seasonal diet : For Jeolsik(major seasonal diet), the usage rates are as follows : D’ockguk(87%) for Jeongwolchoharu, Ogokbab(77.6%) for Jeongwoldaeborum, Patjuk(72.6%) for Dongji, Samsaeknamul(54.1%) for Chusuk. Relatively high usage rates of Surichi-D’ock(40.5%) for Dano and Mandu(40.5%) for Suddalgumumnal are probably due to the immigrated people from this area and the geographical effect. The consumption rates of Sisik(minor seasonal diet) for Chunghwajeol, Samjinal, Youdooil, Chungyangjeol and Muoil are about 10% and the rates for Chopail and Chilsuk are followed. Gaejang and Nangmyon for Sambok used as a rate of 32%. 5) Others : Table pattern; Table for one person(4.7%), table for two(16.7%), table for several(64.2%), table with chair(14.4%) are used. Serving pattern; All-together style(69.7%), monopoly style(24.0%), personaldish style(6.3%) are used. Cooking ware; Among 95 varieties, Doma and Jangban are used most(62.7%) and Pulmae, Poonju and Budulgori are never used. Nine sorts besides Jeongoltle are used as a rate of less than 1%. About 25% of total subjects were the immigrants from other areas. Some of them were moved in due to Chunggamrok. In conclusion, the usage of the traditional food is thought to be maintained well despite of the rapid change to incustrialized society because the native Kyungsangdo foods are combined with foods from the neighboring Kwangwondo, Chungchongdo and northern area.