• Journal of the Korean Society of Earth Science Education
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• v.9 no.3
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• pp.243-254
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• 2016

This study investigated that internalized images of earth scientist's work of 110 high school students who complete a course in Earth Science I through drawing. As a result that reflected the character of earth science as a school subject, it is shown that nearly half of the students believe that earth scientist's working place is outside. An object of study is limited to such areas as astronomy and geology, it says that students has little understanding of areas of atmospheric and oceanic sciences. There are lots of answers that tools for working are telescope or microscope, it reveals a huge difference between the results of advanced research that analyzed the typical experimental devices, and students realized that working is not invention but survey. We should try students to recognize earth scientist as a job with relation to their future.

• Journal of the Korean Society of Food Culture
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• v.16 no.5
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• pp.407-415
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• 2001

The purposes of this study were to assess th importance and performance of food suppliers and to explore the ways to improve the school foodservice purchasing management. The questionnaire regarding purchasing was composed of two parts. The part one consisted of questions on general characteristics of dieticians and school foodservice operations, and the part two was composed of questions on the importance & performance of food suppliers. Completed questionnaires were received from 286 dieticians of elementary school foodservice operations in Seoul. Statistical data analysis was completed using the SPSS/win for descriptive and t-test. In dieticians' demographic data, 36.6% were over 30 years old, 32.4% were $28{\sim}29$ years of age and 31.0% were below 27years old. Most of the respondents(68.3%) had overall working experiences less than 58 months and almost half of them(56.3%) were married. The school foodservice operations which employed a chef were 50.3%. The food suppliers' attributes that were recognized by the dieticians with high value of mean importance scores were: food quality, maintenance of food quality, accuracy in filling orders, quality of delivery facilities, on time delivery and packaging. Average mean score for importance was 4.33('important') out of 5 and mean score for performance was 3.50('so-so') out of 5. By IPA techniques, the attributes that deserve higher attention were those that ranked high in importance and low in performance(Quadrant A). The coordinates in Quadrant A were geographical location of supplier, maintenance of food quality, provision of information on cost variation and salesman's knowledge.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.129-132
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• 2010

The epidemiology of reported food-borne disease (FBD) outbreaks from 2001 to 2008 in Korea nd Japan were compared in this study. The outbreak rate of FBD in Japan was significantly higher although the average umber of patient in each outbreak in Korea was much higher. In both countries, summer was the season when most FBD outbreaks occurred. The comparison study revealed that FBD outbreaks in spring were more frequent in Korea, and outbreaks in winter were more frequent in Japan. Almost half of FBD outbreaks were observed at restaurants in both countries while FBD outbreaks at schools and work-places in Korea were much higher than in Japan. The most frequent cause of bacterial FBDs in Korea was pathogenic Escherichia coli followed by Salmonella species. On the other hand, Campylobacter jejuni was the most frequent source of bacterial FBDs in Japan. Norovirus, which is elated to uncontrolled hand hygiene and involvement of ill food workers, was the main cause of viral FBDs in both countries. In conclusion, there are common epidemiological characteristics as well as several differences in FBD outbreaks of Korea and Japan. These are suggested to be originated from the characteristic of climate, food sources, and life styles in two countries. Establishment of stricter control and surveillance system for FBD outbreaks are required or prevention and reduction of FBD outbreaks in both countries.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1056-1064
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• 2015

This study was designed to provide the basic data of an effective nutrition education for desirable lifestyle and dietary habits to improve the nutritional status for the elderly by investigating health-related lifestyle, dietary habits, nutritional knowledge, and food intake of the elderly. The subjects included 58 elderly men and 146 elderly women. 35.8% had no more than an elementary school education. Most subjects (54.4%) were widows/widowers. Most subjects (71.0%) made over 150,000 won. 52.5% of subjects lived in houses. Smoking, drinking, exercise, the average sleeping time were significantly difference between the gender (p<0.05). In terms of dietary habits, our results showed that 80.9% of respondent eat regularly meals, including breakfast (83.5%). Both sexes prefer soft and salty food. Women enjoys more spicy and salty food compared with men and then shows meaningful difference (p<0.05). Their favorite meals are soup, stew, salad and boiled vegetables. Compared to women, men have a higher rate of correct answers about questions related to nutrition knowledge as showing significantly difference (p<0.05). In a study of dietary habits, they take in carbohydrates with the highest percentage and following by vegetables and fruits. The amount of meat, first and egg they eat is more than the previously. Eating meat is higher men as showing significant difference (p<0.05). In summary, nutritional status for the elderly shows healthy lifestyle and diet about half of those and most them try to live healthy life in future. It is hope that the elderly may need to learn proper nutrition knowledge for healthy lifestyle and nutrition education and counseling for building up healthy lifestyle and desirable dietary habits. Furthermore, it is necessary to start work to establish a baseline nutritious evaluation for the elderly and at a time to study the development of standard eating tool proven reliability and validity, consequently to provide a basic framework for the evaluation of nutritional status.

• Culinary science and hospitality research
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• v.5 no.1
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• pp.27-48
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• 1999

This article a little bit lack of elements for the basis of study of health care in the respect of taking a certain expert group as the sample. However researcher chose people who is in same situation with himself and tried to make clear how to do for their behavior of health care to know that how the experts groups are taking care of their health. For the study, the main aim of this article is studying the health care situation of experts group which is taking crucial role in the economy, society and cultural field. When it comes to the experts group's health care by eating habits and exercise related program is, first, it indicates that most people are eating for their health, lives and work through the analysis of responds; they eat food for their health and their health, lives or task.(Surely they family-centered structure. Third, 78% of 40s group responded that they enjoy finding good restaurants while 20s to 30s are enjoying fastfood and instant food instead of Korean traditional foods. fourth, health care by the exercise is done in one or half one hour and the dependant exercises like jogging or swimming which can be done whenever they have time are perferred to group exercise. It's desirable that one has to take care of himself with systematic and effective way. But it's very difficult and care for most people to take care of themselves, so they have to make the program and practice it systematically. The result from this study shows that practicing the health related program rationally, at the same time increasing leisure time and doing dependant or group exercise, taking a walk, and various kind of exercise considered spending money are more common than eating foods for health care. These are regarded as a desirable phenomenon in terms of the health care.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.112.2-112.2
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• 2011

We carry out a systematic study of HI shells and supershells in the first Galactic quadrant (l = $32^{\circ}$ to $77^{\circ}$, b = $-10^{\circ}$ to $10^{\circ}$) using the "Inner-Galaxy Arecibo L-band Feed Array (I-GALFA)" HI 21-cm survey data. The high-resolution (3.'4) and high sensitivity (0.2 K) of the survey provide us an opportunity to exploit the true nature of the sources detected in previous low-resolution studies and also to detect faint and/or small shells that were not detectable before. Our work is composed of three parts: (1) confirm the objects in the low-resolution (about 30') catalog of Heiles (1979), (2) search for fast-expanding HI shells associated with Galactic supernova remnants (SNRs), and (3) search for new shell structures. Among the 21 Heiles' supershells in the I-GALFA survey area, we confirm fourteen. The high resolution data reveal their complex morphology, and provide direct evidence for expansion in some sources. Among the 39 Galactic SNRs in the survey area, we find five with associated fast expanding HI shells, which is consistent with previous results. A remarkable result from the SNR study is the detection of HI gas at very high negative velocities in the SNR W44 that should be from the approaching part of the HI expanding shell. This is the first time to detect both the approaching and receding sides of an expanding shell in HI 21-cm emission line in SNRs. We have found 33 new shell candidates of angular sizes ranging from 0.5 to 6.5 degrees, half of which appear to be expanding. We summarize these results and discuss some individual interesting objects in detail.

• The Korean Journal of Ceramics
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• v.4 no.4
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• pp.279-285
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• 1998

The $UO_2$ pellets are usually sintered under hydrogen gas atmosphere. Hydrogen gas may cause unexpected early failure of the refractory bricks in the sintering furnace. In this work, nitrogen was mixed with hydrogen to investigate the effect of nitrogen gas on a failure machanism of the refractory bricks and on the microstructure of the $UO_2$ pellet. The hydrogen-nitrogen mixed gas experiments show that the larger nitrogen the mixed gas contains, the less the refractory materials are reduced by hydrogen. The weight loss measurements at $1400^{\circ}C$ for fire clay and chamotte refractories containing high content of $SiO_2$ indicate that the weight loss rate for the mixed gas is about half of that for the hydrogen gas. Based on the thermochemical analyses, it is proposed that the weight loss is caused by hydrogen-induced reduction of free $SiO_2$ and/or $SiO_2$ bonded to $Al_2O_3$ in the fire clay and chamotte refractories. However, the retardation of the hydrogen-induced $SiO_2$ reduction rate under the mixed gas atmosphere may be due to the reduction of the surface reaction rate between hydrogen gas and refractory materials in proportion to volume fraction of nitrogen gas in the mixed gas. On the other hand, the mixed gas experiments show that the test data for $UO_2$ pellet still meet the related specification values, even if there exists a slight difference in the pellet microstructural parameters between the cases of the mixed gas and the hydrogen gas.

• Safety and Health at Work
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• v.6 no.1
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• pp.71-74
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• 2015

Obesity and fitness have been identified as key health concerns among USA firefighters yet little is known about the current habits related to exercise and diet. In particular, high-intensity training (HIT) has gained increasing popularity among this population but limited quantitative data are available about how often it is used and the relationship between HIT and other outcomes. Using survey methodology, the current study evaluated self-reported HIT and diet practice among 625 male firefighters. Almost one-third (32.3%) of participants reported engaging in HIT. Body composition, as measured by waist circumference and percentage body fat, was significantly related to HIT training, with HIT participants being approximately half as likely to be classified as obese using body fat [odds ratio (OR) = 0.52, 95% confidence interval (CI) = 0.34-0.78] or waist circumference (OR = 0.61, 95% CI = 0.37-0.98). Those who engaged in HIT were more than twice as likely as those who did not (OR = 2.24, 95% CI = 1.42-3.55) to meet fitness recommendations. Findings highlight directions for future prevention and intervention efforts.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.2005-2012
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• 2019

This work investigated the radiation attenuation characteristics of three series of tellurite glass systems with the following compositions: 30PbO-10ZnO-xTeO₂-(60-x)B₂O₃ where x = 10, 30, 40, 50 and 60 mol%, xBaO-xB₂O₃-(100-2x)TeO₂ with x = 15-40 mol% and 50ZnO-(50-x)P₂O₅-xTeO₂, where x = 0, 10, .40 mol%. The results revealed that the attenuation parameters in all the samples decrease with increase in the energy, which implied that all the samples have better interaction with gamma photons at low energies and thus higher photon attenuating efficiency. From the three systems, the samples coded as PbZnBTe60, BaBTe70 and ZnPTe40 have the lowest half value layer values and accordingly have superior photon attenuation efficacy. The maximum effective atomic number values were found for energy less than 0.1 MeV particularly near the K-edges absorption of the heavy atomic number elements such as Te, Ba and Pb. At the lowest energy, the Z_eff values are found in the range of 62.33-66.25, 49.43-50.81 and 24.99-35.83 for series 1-3 respectively. Also, we found that the density of the glass remarkably affects the photon attenuation ability of the selected glasses. The mean free path results showed that the PbO-ZnO-TeO₂-B₂O₃ glass system has better radiation shielding efficiency than the glass samples in series 2 and 3.

• Korean Journal of Optics and Photonics
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• v.10 no.2
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• pp.107-113
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• 1999

Low-aberration holographic scanners that eliminate the need for lenses and mirrors promise to greatly reduce the cost of laser printers and image scanners. In this study, a holographic optical element that can simultaneously scan and focus a laser beam is designed with analytic ray tracing method. An analytic and experimental work is conducted in which we investigated the hologram structure and hologon configuration for linear aberration-free scanning. For a prototype scanner, a He-Ne laser is used to manufacture and reconstruct the hologram, and the measured bow is about $\pm$133$\mu\textrm{m}$ and spot size(half-intensity beamwidth) in under 100$\mu\textrm{m}$ for a 300 mm scan length without using a correcting lens or mirror. The diffraction efficiency is about 55$\pm$5%, which is acceptably flat. The experimentally measured results agrees with the computed values. From this fact, we can conclude that the computed results using ray tracing method are practical and useful values, and have a potential for use in high resolution laser printers.