• Progress in Superconductivity
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• v.13 no.1
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• pp.1-6
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• 2011

Measurement of magnetic signals generated from electric activity of myocardium provides useful information for the functional diagnosis of heart diseases. Key technical component of the magnetocardiography (MCG) technology is SQUID. To measure MCG signals with high signal-to-noise ratio, sensitive SQUID magnetic field sensors are needed. Present magnetic field sensors based on Nb SQUIDs have field sensitivity good enough to measure most of MCG signals. However, for accurate measurement of fine signal pattern or detection of local atrial fibrillation signals, we may need higher field sensitivity. In addition to field sensitivity, economic aspect of the SQUID system is also important. To simplify the SQUID readout electronics, the output voltage or flux-to-voltage transfer of SQUID should be large enough so that direct measurement of SQUID output can be done using room-temperature preamplifiers. Double relaxation oscillation SQUID (DROS), having about 10 times larger flux-to-voltage transfers than those of DC-SQUIDs, was shown to be a good choice to make the electronics compact. For effective cancellation of external noise inside a thin economic shielded room, first-order axial gradiometer with high balance, simple structure and long-baseline is needed. We developed a technology to make the axial gradiometer compact using direct bonding of superconductive wires between pickup coil and input coil. Conventional insert has mechanical support to hold the gradiometer array, and the dewar neck has equal diameter with the dewar bottom. Boiling of the liquid He can generate mechanical vibrations in the gradiometer array due to mechanical connection structure. Elimination of the mechanical support, and direct mounting of the gradiometer array into the dewar bottom can reduce the dewar neck diameter, resulting in the reduction of liquid He consumption.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.5
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• pp.27-37
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• 2020

As domestic meat consumption increases, the broiler production industry has been larger and denser. The concentration of particulate matter (PM) and harmful gases generated is also increasing inside livestock house. However, the current research status of PM exposed to farm workers and the health effects are in the early stage. To understand PM concentration affecting workers in the broiler house, field monitoring was conducted according to its size distributions. Concentrations of PM₁₀, PM_2.5, and TD (Total Dust) were monitored using personal air samplers with teflon filter during working and moving periods considering the ventilation systems of 6 broiler houses. The purpose of this study is to monitor the PM concentration in the experimental broiler houses operated by forced ventilation system generally used in Korea and to evaluate the regional concentrations through airflow pattern. The PM concentrations were increased from inlet to outlet vents resulting in 1,872 of TD, 1,385 of PM₁₀, and 209 ㎍/㎥ of PM_2.5, respectively. The TD and PM₁₀ concentrations were increased when the workers and broilers were moving. Among them, the particle size that occupied the largest amount of PM was 13.75 ㎛. These results suggest that personal protection equipments are important to reduce the health effect from PM inhalation.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.90-101
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• 2009

An objective of this study is to suggest a procedure to evaluate vehicle emissions regardless of the driving pattern. Field experiments using portable emission measurement system were conducted under the real world driving cycle. Standardized average for NOx, $CO_2$ emission and fuel consumption rates were calculated while the vehicle specific power distribution within each vehicle speed bin was taken into consideration. Composite emission factor and fuel economy, which were obtained based on the standardized average results and traffic statistics, showed good similarity to those acquired through the conventional chassis dynamometer tests qualitatively as well as quantitatively. Considering that a conventional method obviously has a limitation to reflect various characteristics of the real world, the new approach suggested in this study can be used as an alternative procedure to collect more specific data to establish the mobile emission factors.

• Journal of Fashion Business
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• v.2 no.4
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• pp.69-78
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• 1998

The purpose of this study was to identify the variables which could characteristics the New Young Generation (NYG), to investigate the relationship between level of NYG characteristics and information searching related to underwear purchasing, and the differences level of the NYG characteristics according to demographic variables (sex, grade, major), and examine the casual relationships of demographic variables (sex, place of growing background, parent's education) and level of the NYG characteristics on information searching related to underwear purchasing. The subjects were 723 college students (female = 324, male=398) living in Seoul and Kyuggi were participated in this study. The NYG is limited to person who born after 1970's. The result of this study were as follows; 1. Five factors of New Young Generation oriented characteristics were identified; F.1 'Info-telecommunication(Info-Telecom)'; F.2 'Family and Marriage'; F.3 'Consumption pattern'; FA 'Self-centered (Individualism)'; F.5 Work/Career oriented. 2. The relationship between the NYG characteristics and information search in underwear purchasing were significanted. 3. In demographic variables, gender, grade, and major were partially significant differences. 4. In male students, the result of the casual relationship between demographic variables with NYG characteristics and the level of the NYG in underwear purchasing showed that grade, background of grownplace, level of parent's education were significanted the high level of info-telecom factor associated with higher grade, city-grown, higher level of parent's education. In conclusion, the result showed that the level of NYG characteristics was significant to male students and specially for grade older students. The background of parent's education level was the another important variables to predicting the NYG characteristics. Finally the higher the NYG characteristics, the more information search in underwear purchasing.

• Journal of the Korean Society of Food Culture
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• v.19 no.4
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• pp.447-459
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• 2004

Fortified foods are consumed widely in modem society according to increased concern on health oriented foods. This study investigated the patterns of vitamin-and/or mineral-fortified food use among 677 teenage students(13-18 years of age) in Chungnam province and Daejeon city in Korea using questionnaire. More than 63.7% of total subjects consumed more than one package of fortified foods belonged to more than three categories of five categories including sweets/biscuits, ramyons, beverages, milk and dairy products, and breads as a frequency of more than 1-2 times/week during previous three months prior to present survey. Consumption of fortified foods was higher in middle school students than in high school students(p<0.05), and in females than in females(p<0.001). Users of fortified foods took the snacks more often(p<0.001), and they tended to believe more positively that fortification can be helpful in health maintenance than did non-users. Users preferred vitamin C and Ca(calcium) as a fortified nutrient. Major fortified nutrients in fortified foods taken by users were various; vitamin B-complex and Ca from sweets/biscuits, Ca from ramyons, vitamin C and Ca from beverages, Ca and iron from milk and dairy products and breads. These results suggest that fortified foods are used commonly and are influenced by several factors among teenagers. Types of fortified nutrient, in fortified foods taken by subjects, are various and fortification is performed unspecifically. As a consequence both nutrition education and government regulation on fortified foods should be enforced to maximize the benefits and minimize the hazard of their use.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.499-507
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• 2005

The purpose of this study is to draw attention to the distinction of Korean food as well as to find ways to universalize Korean food. Not only does Korean food a big part of representing the Korean culture itself, the ingredients in the Korean food are extremely nutritious. The excellence in the ingredients has been verified through scientific studies over and over. Today, this is recognized widely by the food experts in the U.S. This study also points out some of the hurdles in universalizing Korean food. First of all, many people around the world are not aware of the positive aspects of the Korean food. There have been minimal efforts, if at all, to find ways to make fusion Korean food to be part of a world cuisine. The lack of research and development in the Korean food industry also does not help the situation much. Lastly, the limited knowledge of the actual people working in the food service sector regarding Korean food hinders the Korean food going universal. Currently, the food industry in the U.S. is quite favorable for Korean food to enter its markets to become part of the American cuisine. The Americans' appetite continues to change towards more healthy living leaning them naturally towards Asian food. For Korean food to become part of the American cuisine, the follow recommendations are given in the study: 1) Korean food must be localized, become a fusion cuisine; 2) standardize the cooking method; 3) change the focus to rice-centered trend food; 4) foster more Korean food experts; and, 5) promotion of strengthening food advertisements while increasing research and development. It is also important during this whole process, traditional Korean food be discovered and implemented to the overall food program in universalizing Korean food.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.10
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• pp.579-584
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• 2014

In this paper, we propose beamsapce MIMO(mulitple input multiple output) system using patch ESPAR(Electronically Steerable Parasitic Array Radiator) antenna. When using conventional monopole ESPAR antenna, we have advantages cost of hardware and power consumption of RF cirsuit because of single RF chian. But it is difficult to apply to small portable mobile device. Therefore we design patch ESPAR antenna in order to reducing volume and analyze performance of BS MIMO system that is able to MIMO communication with single RF chain. In This paper, we confirm beam pattern of designed patch ESPAR antenna is steered as ${\pm}15^{\circ}$ elevation angle. Furthermore, we design BS MIMO system using this ESPAR antenna and confirm BER performance of this system.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.06a
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• pp.356-360
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• 2002

Polluting the air with such pollutants as CO, H₂S and SO₂, industrial development huts increased the danger of gas toxication. Futhermore, as the: living standard goes higher, the consumption of explosive hydrocarbonic gases such as butane(C₄H/sub 10/) or propane(C₃H/sub 8/) has been soaring, which results in the danger of a gas explosion. As measures to cope with such dangers, the development of highly sensitive gas sensors, gas detectors adopting gas-sensing technologies, and gas recognition systems are urgently required. The objective of the present research is to develop a gas recognition system that is capable of identifying specific types of selected gases by formulating a semiconductor-typed gas sensor array, which not only improves the selectivity of semiconductor-typed gas sensors but also minimizes the erect of drifts on a single sensor signal, and applying the input pattern data of gases detected by the array to a neural network.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.217-232
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• 2020

The purpose of this study is to organize prior research related to e-commerce activation factors available to stakeholders in the online distribution industry, and to conduct FGI with e-commerce experts to calculate the importance of each factor in order based on the 3 Level Service Model of Kwon Hyeog-in (2010), the key factors derived through the preceding study and the FGI were structured and the weighting of each factor was derived using AHP methodology. In the higher factors, the private sector (0.542) > communes (0.237) > public (0.2222) appeared to be important. Sub-factories included 'search service development' (0.0970)', 'recommendation service development (0.0805)', 'consumer needs analysis (0.0534)', 'consumer consumption pattern analysis (0.0505)' and 'other platform-linked service development (0.0450)', in the order of weighting down, indicating each of the factors within the top 15 priority. The results of this study will be utilized throughout the e-commerce industry as well as e-commerce enterprises, providing an academic foundation for the rapidly growing e-commerce ecosystem.

• International Journal of Contents
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• v.11 no.2
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• pp.31-36
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• 2015

Recent years have seen a significant increase in demand for multimedia data over wireless sensor networks for monitoring applications that utilize sensor nodes to collect multimedia data, including sound and video. However, the multimedia streams generate a very large amount of data. When data transmission schemes for traditional wireless sensor networks are applied in wireless multimedia sensor networks, the network lifetime significantly decreases due to the excessive energy consumption of specific nodes. In this paper, we propose a data compression scheme that implements the Chinese remainder theorem to a wireless multimedia sensor network. The proposed scheme uses the Chinese Remainder Theorem (CRT) to compress and split multimedia data, and it then transmits the bit-pattern packets of the remainder to the base station. As a result, the amount of multimedia data that is transmitted is reduced. The superiority of our proposed scheme is demonstrated by comparing its performance to that of an existing scheme. The results of our experiment indicate that our proposed scheme significantly increased the compression ratio and reduced the compression operation in comparison to those of existing compression schemes.