• Culinary science and hospitality research
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• v.20 no.5
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• pp.119-123
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• 2014

This study was intended to investigate food habits, dietary variety and the effects of nutrient intake of female college students. Food habits such as regularity of meal time, repast of breakfast, lunch, and supper, and duration of meal were assessed via a self reporting questionnaire, 24 hrs recall method for nutrient intake was obtained from 155 female college students in Yangju-si. Dietary variety was assessed by dietary diversity score(DDS). The mean height and weight of the subjects were $161.25{\pm}3.52cm$ and $52.26{\pm}4.52kg$, respectively. The dietary habits of female college students was generally inadequate. In the survey of dietary habits, the ratio of skipping breakfast 3~6 days a week in total subjects was 87.09%, showing a rather higher ratio of skipping breakfast. In the evaluation of nutrient intakes by DDS, subjects who had higher DDS had significantly higher nutrient intakes of energy, protein, carbohydrate, fiber, calcium, phosphate, iron, vitamin A, vitamin C, and cholesterol(p<0.05). There was a great difference in nutrient intakes, suggesting the risk of nutritional imbalance. These findings suggest that nutritional education based on female college students' eating variety and dietary habits(regularity of meal time, skipping breakfast and night snacks per week, and duration of meal) may be required to improve dietary variety. it is considered that the improvement in dietary habits will contribute to the improvement of nutrition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.906-911
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• 2001

In this paper, LPI(low probability of intercept) and AJ(anti jamming) performance of the chirped BPSK system are analyzed. In the chirp method the cyclostationary of the signal is eliminated, since the instantaneous frequency is varied randomly within the whole spread bandwidth. Therefore, chirp method is considered for good LPI system against DAM(delay-and-multiplier) or SC (squaring circuit) interceptor which detects the chip rate or carrier frequency. Longer chirp duration makes the LPI performance better. From the simulation results, the chirp method has better AJ performance than DS(direct sequence) system in the PBNJ(partial band noise jammer) channel. At the same JSR(jammer to signal power ratio) level, chirped BPSK system has more robust AJ performance against MTJ(multi-tone jammer) than PBNJ.

• Journal of ILASS-Korea
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• v.16 no.1
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• pp.44-50
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• 2011

An object of this study is to understand the correlation of injection characteristics and injector dimensions according to biodiesel mixture. The Injection characteristics of different types of common-rail injectors are the number of nozzle holes (5~8), jet cone angle ($146^{\circ}{\sim}153^{\circ}$), hydraulic flow rate (830~900 ml/min) injection quantity and response time. Prior to characteristic experiment, the reference injector has been selected in 6 candidates injectors under the investigation of injected quantity according to the biodiesel mixture so that injector type can be determined. The injector is used for the characteristic experiment which varied the various operating conditions including pressure 23 MPa, 80 MPa, 160 MPa, changing in injection duration 0.16 ms~1.2 ms and even mixture ratio. The result shows that the nozzle hole number and cone angle influence the injection quantity much more than nozzle hole diameter at low injection pressure and the nozzle hole diameter at high injection pressure, post injection duration.

• Journal of Nutrition and Health
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• v.23 no.4
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• pp.257-269
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• 1990

We designed this study to compare the total body fat content and its distribution of diabetics with those of normal subjects. Skinfold thicknesses at eight sites(subscapular, subcostal, abdomen, suprailiac, triceps, forearm, thigh and calf) and body circumferences at five sites(waist, hip, arm, thigh and calf) were measured on 220 diabetics(82 male, 138 female) and on 160 nondiabetic subjects(male 57, female 103). We matched 92 pairs with diabetics and nondiabetic control subjects by sex, age, body weight and height, and made comparisons between two groups(case-control study). The results were as follows: 1) There was no significant difference in total body fat content of diabetics and control (male ; 20.40$\pm$2.12%, 19.20$\pm$3.52%, female ; 26.46$\pm$2.53%, 27.01$\pm$2.92%, respectively). However, body muscle mass(%) in diabetic men(33.37$\pm$4.19%) was significantly lower than in nondiabetic men(38.16$\pm$7.11%). 2) Diabetics, especially women, were characterized by more central body fat than control. That is, indices of centrality of body fat distribution(subscapular/triceps skinfold : STR, central/peripheral fat : CPR) of diabetics were higher than those of control. 3) Body weight, body mass index and %IBW(current body weight$\times$100/ideal body weight) had negative correlations with duration of diabetes(r=-0.23~-0.33), but total body fat content(%) and indices of body fat distribution, such as STR, CPR, waist/hip girth ratio(WHR), and waist/thigh girth ratio(WTR), were not related to duration of diabetes.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.2
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• pp.389-396
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• 1994

It is very important to clarify the ignition and flame propagation processes of methanol fuel in the Spark-ignition engine. High speed Schlieren photography and pressure trace analyses were used to study on combustion characteristics of methanol fuel in a constant volume chamber. Methanol-air mixtures equivalence rations from lean limit to 1.4 were ignited at initial pressure (0.1, 0.3, 0.5 MPa), temperature (313 343, 373 K) and ignition energy (40, 180 mJ). As the result of this study, we verified the characteristics such as ignition delay, effective thermal efficiency, flame propagation velocity, lean limit, ignitability and combustion duration. Obatained results are as follows. (1) The time to 10% reach of maximum pressure was 40-50% of the total combustion duration for this experimental condition hardly affected by equivalence ratio. (2) The Effective thermal efficiency, as calculated from maximum pressure was the highest when the mixture was slightly lean $({\phi} 0.8-0.9)$ and maximum pressure was the highest when the mixiture was slightly rich $({\phi} 1.2-1.2).$

• Journal of the Korean Society of Tobacco Science
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• v.7 no.1
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• pp.49-55
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• 1985

low grade leaves of flue-cured (N.C. 2326) and air-cured (Br 21) have been heated at $140^{\circ}C$ for 10 and 20 minutes, respectively. As heating duration increased, each contents of nicotine, total nitrogen, total sugar and free amino acid decreased in both leaves. The result obtained from this experiment are as following 1. Nicotine content decreased in both leaves. Heating for 10 and 20 minutes showed respectively nicotine decrease of 13.2% and 21.6% for Br 21 and 8.2% and 13.2% for N.C.2326. Decrease of total nitrogen and total sugar was inversely proportional to the heating duration. N.C. 2326 in the decrease out numbered Br.21 by the ratio 2: 1 for 10min.-heating, and 5:4 for 20 min.-heating. 3. Total free amino acid was decrease by 17.1% and 13.85 for N.C. 2326 and Br 21, respectively when heated for 10 min., and 25.6% and 26.5% respectively when heated for 20 min. When sucrose was added to Br 21, th decrease ratio of total free amino acid of Br.21 was increased. It is suggested that the addition of sucrose could promote the browning reaction in Br 21 leaves.

• Journal of Chest Surgery
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• v.24 no.4
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• pp.421-427
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• 1991

Atrial fibrillation[Af] is closely related to thrombus in left atrium, systemic embolism, and loss of the contribution of atrial contraction to cardiac output. Therefore maintenance of sinus rhythm[SR] is undoubtedly hemodynamically superior to Af in the clinical course of mitral valvular disease especially in the unstable period immediately after surgery. In this article, the conversion rate and the factors influencing the conversion of Af to SR after surgery were studied. Ninety-three patients with mitral valvular replacement at Chungnam National University Hospital were analysed with electrocardiography before and after surgery during the period from June 1985 to June 1990. Eighty patients presented Af before surgery. Twenty-four[30Yo] of the patients were converted to SR[A group] and fifty six presented continuous Af after surgery[B group]. The duration of preoperative Af, preoperative left atrial dimension[LAD], preoperative functional status[NYHA classification] and cardiothoracic[CT] ratio were factors influencing the conversion of Af to SR after surgery. The mean preoperative duration of Af was 3.5$\pm$2.6yr in group A and 7.6$\pm$4.9yr in group B. The mean preoperative LAD was 53. 7$\pm$9.4mm in group A and 62.5$\pm$11.2mm in group B. Before surgery, eleven patients[46%] were belong to NYHA class I, II in group A and eight[14%] in group B. The preoperative CT ratio was 62$\pm$6% in group A and 69$\pm$8% in group B.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1103-1106
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• 2004

The objective of this study is to induce the design drought rainfall by the methodology of L-moment including testing homogeneity, independence and outlier of the data of annual minimum monthly rainfall in 57 rainfall stations in Korea in terms of consecutive duration for 1, 2, 4, 6, 9 and 12 months. To select appropriate distribution of the data for annual minimum monthy rainfall by rainfall station, the distribution of generalized extreme value (GEV), generalized logistic (GLO) as well as that of generalized pareto (GPA) are applied and the appropriateness of the applied GEV, GLO, and GPA distribution is judged by L-moment ratio diagram and Kolmogorov-Smirnov (K-S) test. As for the annual minimum monthly rainfall measured by rainfall station and that stimulated by Monte Carlo techniques, the parameters of the appropriately selected GEV and GPA distributions are calculated by the methodology of L-moment and the design drought rainfall is induced. Through the comparative analysis of design drought rainfall induced by GEV and GPA distribution by rainfall station, the optimal design drought rainfall by rainfall station is provided.

• Journal of ILASS-Korea
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• v.21 no.3
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• pp.155-161
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• 2016

Injected fuel pressure waves of a common rail injector with various current profiles supplied to the injecor were measured using Bosch method. In order to drive the common rail injector, the current in the solenoid should be controlled using what is known as a peak and hold pattern, which consists of a high current level with a short time duration (peak) in the first step and a low current level with a long time duration (hold) in the subsequent step. The current profile can be shaped by swithcing an injector driving power source with the peak and hold waves. The capture, compare and PWM (CCP) pin in the microprocessor was used to generate the combined peak and hold waves. The PWM square wave generated from the CCP pin has a duty ratio of 100% for the peak current and 10% or 30% for the hold pattern. Five patterns of the current profile were generated by combining the peak and hold wave. The common rail pressure is controlled at 75, 100, and 130 MPa. As the fuel rail pressure increases, the variations of the measured fuel injection pressure wave according to the current profiles decrease.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.115-123
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• 2018

In this paper, we consider the applicability of time-hopping(TH) systems for anti-jamming(AJ) communication. We first briefly summarize fundamentals of TH systems and several common jamming scenarios that have been considered in the literature. We then analyze the AJ performance of TH systems under those common jamming environments. From our simulation results, we reveal that among narrow band, partial band, broadband, and sweep jamming, partial band and sweep jamming are the best ones from jammer perspective. For the partial band jamming case, we show that the most effective bandwidth ratio and location are 50 % and 2.5-3.5 Ghz, respectively. For the sweep jamming case, we illustrate that the AJ performance of the TH system is enhanced when the sweep duration approaches to the bit duration. In addition, we pointed out that the most efficient jamming bandwidth ratio is 1/2. Finally, our results show that the TH-BPSK system greatly outperforms the TH-PPM counterpart.