• Journal of Advanced Marine Engineering and Technology
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• v.40 no.1
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• pp.62-68
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• 2016

The fingerprint, which is one of the methods of indoor localization using WiFi, has been frequently studied because of its ability to be implemented via wireless access points. This method has low positioning resolution and high computational complexity compared to other methods, caused by its dependence of reference points in the radio map. In order to compensate for these problems, this paper presents a radio map designed algorithm based on the log-distance path loss model fusing a WiFi and BLE fingerprint. The proposed algorithm designs a radio map with variable values using the log-distance path loss model and reduces distance errors using a median filter. The experimental results of the proposed algorithm, compared with existing fingerprinting methods, show that the accuracy of positioning improved by from 2.747 m to 2.112 m, and the computational complexity reduced by a minimum of 33% according to the access points.

• Journal of Environmental Science International
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• v.24 no.1
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• pp.31-46
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• 2015

In this study, the regional climate (WRF) and air quality (CMAQ) models were used to simulate the effects of future urban growth on surface ozone concentrations in the Seoul metropolitan region (SMR). These analyses were performed based on changes in ozone concentrations during ozone seasons (May-June) for the year 2050 (future) relative to 2012 (present) by urban growth. The results were compared with the impacts of RCP scenarios on ozone concentrations in the SMR. The fractions of urban in the SMR (25.8 %) for the 2050 were much higher than those (13.9 %) for the 2012 and the future emissions (e.g., CO, NO, $NO_2$, $SO_2$, VOC) were increased from 121 % (NO) to 161.3 % ($NO_2$) depending on emission material. The mean and daily maximum 1-h ozone in the SMR increased about 3 - 7 ppb by the effect the RCP scenarios. However, the effect of urban growth reduced the mean ozone by 3 ppb in the SMR and increased the daily maximum 1-h ozone by 2 - 5 ppb over the northeastern SMR and around the coastline. In particular, the ozone pollution days exceeding the 1-h regulatory standard (100 ppb) were far more affected by urban growth than mean values. As a result, the average number of days exceeding the 1-h regulatory standard increased up to 10 times.

• Journal of Preventive Medicine and Public Health
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• v.50 no.4
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• pp.278-281
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• 2017

Since 2006, type 1 diabetes in Finland has plateaued and then decreased after the authorities' decision to fortify dietary milk products with cholecalciferol. The role of vitamin D in innate and adaptive immunity is critical. A statistical error in the estimation of the recommended dietary allowance (RDA) for vitamin D was recently discovered; in a correct analysis of the data used by the Institute of Medicine, it was found that 8895 IU/d was needed for 97.5% of individuals to achieve values ${\geq}50nmol/L$. Another study confirmed that 6201 IU/d was needed to achieve 75 nmol/L and 9122 IU/d was needed to reach 100 nmol/L. The largest meta-analysis ever conducted of studies published between 1966 and 2013 showed that 25-hydroxyvitamin D levels <75 nmol/L may be too low for safety and associated with higher all-cause mortality, demolishing the previously presumed U-shape curve of mortality associated with vitamin D levels. Since all-disease mortality is reduced to 1.0 with serum vitamin D levels ${\geq}100nmol/L$, we call public health authorities to consider designating as the RDA at least three-fourths of the levels proposed by the Endocrine Society Expert Committee as safe upper tolerable daily intake doses. This could lead to a recommendation of 1000 IU for children <1 year on enriched formula and 1500 IU for breastfed children older than 6 months, 3000 IU for children >1 year of age, and around 8000 IU for young adults and thereafter. Actions are urgently needed to protect the global population from vitamin D deficiency.

• The Journal of Engineering Research
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• v.6 no.1
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• pp.5-14
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• 2004

Finding a solution to a constraint satisfaction problem requires choosing values for variables so as to satisfy the constraints of the problem. A constraint is simply a logical relation among several unknowns (or variables), each taking a value in a given domain. Conventional constraint-based scheduling systems are not enough to satisfy the all constraints because there are conflicts between them. In this paper, we propose a method for interactive scheduling, which have two major problems: first, it is hard to satisfy concretely all various kinds of constraints, and second, the search space is extremely large and requires a long execution time. To solve the above problems, we introduce the Interactive Scheduling System (ISS) that interacts with the user to exchange suggestions each other. Our system is performed in two steps: knowledge base generation of an initial assignment and iterative improvement with the user(host or internet client) to satisfy the constraints. Applying our system, we actually constructed timetables for our university, where the scheduling time is considerably reduced.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.10
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• pp.1172-1180
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• 2007

OFDM system has very good high spectral efficiency and the robustness to the frequency-selective fading. Because of the high PAPR, OFDM signals can be distorted in nonlinear HPA(High Power Amplifier). So, to overcome the nonlinear distortion, it is very important to reduce the IMD value. With respect to the BER performance, IMD reduction method is better than the PAPR reduction method. However, IMD reduction method has much more system complexity because of the additional FFT processor in transmitter. In this paper, we study the OFDM communication system based on the IMD reduction method using SPW method. A new IMD reduction method is proposed to reduce the computational complexity. SPW method is to divide the input OFDM data into several sub-blocks and to multiply phase weighting values with each sub-blocks for the reduction of PAPR or IMD. Unlike the conventional method, the system size and computational complexity can be reduced.

• Korean Journal of Community Nutrition
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• v.25 no.4
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• pp.329-339
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• 2020

Objectives: This study was undertaken to evaluate the intake of vitamins and minerals from dietary supplements (DSs) in Korean adults and elderly. Methods: Data for this study was generated from the 2017 Korea National Health and Nutrition Examination Survey (KNHANES). We analyzed 4,204 individuals aged 19 years and older (2,579 users and 1,625 non-users). The survey included 24-h recall questions on food and DS intakes, as well as questions on DS use over the past year. The nutrient DSs evaluated were calcium, phosphorus, iron, vitamin A, thiamin, riboflavin, niacin, and vitamin C. Total nutrient intakes were obtained by combining nutrient intakes of foods and DSs consumed by each subject. Results: Most micronutrient intakes from food (except for thiamin) in adult users, and the four micronutrient intakes (iron, vitamin A, vitamin B₂ and vitamin C) in elderly users, were significantly higher than values obtained in non-users. For total intake of nutrients and DSs, both adult and elderly users had a significantly higher intake than non-users. While proportions below Estimated Average Requirements for all micronutrients by adding respective DSs in users were significantly reduced in adults and elderly as compared to non-users, the proportions of above Tolerable Upper Intake Levels for calcium and vitamin A in adults, and vitamin A in elderly, were significantly increased. In the total subjects examined, consumption of DSs was associated with lower odds ratios of undernutrition of micronutrients, and with higher odds ratios of overnutrition of calcium, iron, and vitamin A, as compared to non-users of DSs. Conclusions: Although DSs consumption by adults and the elderly improves the micronutrient status, it also increases the risk of excessive intake of certain vitamins and minerals.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1264-1269
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• 2014

This study investigated the effects of rice starch addition, including native, acetylated, and hydroxypropy-lated rice starch, on the quality characteristics of instant fried noodles. Compared to 100% wheat flour (control), flours containing acetylated or hydroxypropylated rice starch showed reduced initial pasting temperatures as well as peak and breakdown viscosities as determined using a Rapid Visco-Analyzer (RVA). The addition of acetylated and hydroxylated rice starch as well as native rice starch increased cooked weight, volume, and water absorption of the fried noodles compared to control noodles. The addition of native rice starch tended to increase softness of noodles, whereas addition of acetylated or hydroxypropylated rice starch significantly lowered hardness, gumminess, and chewiness values. The results of the sensory evaluation indicate that noodles containing rice starch showed improved sensory characteristics such as color, appearance, flavor, taste, and texture. Especially, acetylated rice starch could be used to improve eating quality of instant fried noodles.

• Nutritional Sciences
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• v.5 no.1
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• pp.13-19
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• 2002

A mutation in the promoter region of uncoupling protein 3 (UCF3), specifically the -55C longrightarrow T transition, may influence an individual's energy metabolism and body weight. The objective of this study was to investigate the effect of a weight reduction program on endocrine functions and body fat distribution, related to UCP3 promoter genotype. Ninety overweight pre-menopausal female subjects participated in the weight reduction program at Yonsei University Hospital, and were placed on a calorie-restricted diet (300 kcal less than their daily requirements) for 12 weeks. After 12 weeks, all subjects on the program lost approximately 5% of their initial body weights and had lower Body Mass Index (BMI) values. Among the 90 women, 56 had a normal (without mutation) UCP3 genotype, while 34 women had mutations in the promoter region of UCP3. Despite similar weight reductions in both groups, a significantly higher decrease in abdominal adipose tissue was observed in the normal UCP3 genotype group, compared to the group with mutations. In particular, there was a significant reduction of fat at the lumbar 1 (Ll) level in the without-mutation group. Serum levels of total cholesterol, apolipoprotein Al were significantly decreased in the without-mutation group, by 4.4% and 5.7% respectively. Serum levels of hormones were not significantly changed in both groups artier the intervention. However, in the group without the mutations, the leptin level significantly reduced by 23.4% (p<0.001). Serum free fatty acid (FFA) concentration was significantly increased in the group with mutation following the weight reduction program. On the other hand, FFA responses were shown similar increases in both groups. In conclusion, although no difference was found in the magnitude of weight reduction in both groups, there were significant differences in body fat distribution and in endocrine function between the groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.635-640
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• 2006

This study was conducted to determine the effect of far infrared ray drying on the microbial and quality changes of vacuum packaged waxy corns, such as microbial growth, rehydration, color differences, weight loss and hardness during the storage at $4^{\circ}C$ and $25^{\circ}C$ for 7 months. After far infrared ray drying for 6 hours at $60^{\circ}C$, 2.32 log CFU/g of total microbial counts in raw waxy corns was enumerated, but no microorganism was detected in steamed or sugar-treated waxy corns. However, no microorganism was observed in all treatments except for control samples until 3 month storage at $4^{\circ}C$, whereas steamed and sugar-treated waxy corns showed 2 and 2.7 log reduction compared to that of control after 3 month storage. Yeasts and molds were more resistant than bacteria against far infrared ray drying at the same conditions. Similar results were observed in $25^{\circ}C$ storage. The degree of gelatinization in raw waxy corns far infrared ray drying changed from 98% to 96.2% after 7 month storage at $4^{\circ}C$, whereas steamed waxy corns with far infrared ray drying changed from 81.14% to 58.73%. Water contents in sugar-treated waxy corns with far infrared ray drying gradually reduced compared to steamed waxy corns as drying time increased. The L values in raw waxy corns far infrared ray drying increased as drying time increased, but L values in steamed or sugar-treated waxy corns significantly reduced after 12 hour far infrared ray drying. Hardness in raw waxy corns was higher than in steamed or sugar-treated waxy corns before storage, but similar hardness was observed between raw- and sugar-treated waxy corns after 9 hour drying. This results showed that the microbial reduction, the enhancement of shelf life and quality establishment of steamed or sugar-treated waxy corns could be maximized by using far infrared ray drying.