• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8C
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• pp.575-582
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• 2008

In this paper we described the process and the results of real-time implementation of G.729.1 wideband speech codec which is standardized in SG15 of ITU-T. To apply the codec on ARM926EJ-S(R) processor core. we transformed some parts of the codec C program including basic operations and arithmetic functions into assembly language to operate the codec in real-time. G.729.1 is the standard wideband speech codec of ITU-T having variable bit rates of $8{\sim}32kbps$ and inputs quantized 16 bits PCM signal per sample at the rate of 8kHz or 16kHz sampling. This codec is interoperable with the G.729 and G.729A and the bandwidth extended wideband($50{\sim}7,000Hz$) version of existing narrowband($300{\sim}3,400Hz$) codec to enhance voice quality. The implemented G.729.1 wideband speech codec has the complexity of 31.2 MCPS for encoder and 22.8 MCPS for decoder and the execution time of the codec takes 11.5ms total on the target with 6.75ms and 4.76ms respectively. Also this codec was tested bit by bit exactly against all set of test vectors provided by ITU-T and passed all the test vectors. Besides the codec operated well on the Internet phone in real-time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.543-550
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• 2018

The rapid growth of IoT technology induced by the fourth industrial revolution has resulted in research into various types of wireless sensors, and applications based on this technology are prevalent in many areas. However, among the various sites where this technology is used, railway bridges and tunnels with lengths of tens of kilometers have problems with data acquisition, due to the signal noise induced by the long distance measurement and EMI induced by the high voltage power feeding system, when conventional electric sensors are used. To overcome these problems, many studies on fiber optic sensors have been conducted as a substitute for the conventional electric sensors. However, restrictions on the types of fiber optic sensors have limited their application in railways. For this reason, a hybrid measurement system with IoT based wireless data communication, in which both electric and fiber optic sensors can be applied simultaneously, has been developed. In this study, in order to evaluate the applicability of the hybrid measurement system developed in the previous study, a real-time test for 4 types of measurement environments, which reflect possible railway sites, is performed. As a result, it was confirmed that the signals from both the electric and fiber optic sensors, which were acquired at a remote area in real-time, showed good agreement with each other and that this measurement system has the potential to handle sensors with a sampling rate of 2.5 kHz. In the future, it is expected that the IoT-based hybrid measurement system will contribute to the improvement of structural safety by enabling real-time structural health monitoring when applied to various measurement sites.

• Journal of Chest Surgery
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• v.49 no.3
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• pp.145-150
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• 2016

Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

• The Journal of the Acoustical Society of Korea
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• v.14 no.2
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• pp.50-61
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• 1995

A time scale modification method yielding rate-modified speech while conserving the characteristic of speech was implemented in real-time using a goneral purpose digital signal processor. Time scale modification changed pronunciation speed only, producing a time difference between the input signal and the modified signal, making it impossible to implement it in real-time. In this thesis, a system was implemented to remove the time difference between the input and modified signals. Speech signals slowed down or speeded up by a physical time scale modification method, such as adjusting the motor speed of the cassett tape recorder, was used as the input signal. Physical modification that controled only the inter speed of the cassette tape player distorted the pitch period of the original speech. In this study, a real-time system was implemented so that the pitch-distorted speech was reconstructed back to the original by fractional sampling pitch shifting using an FIR filter, and this signal was time scale modified to match the cassette tape recorder motor speed using SOLA time-scale medification. In experiments using speech signals medifiedby the proposed method, results obtained using a 16-bit resolution ADSP2101 processor and using computer simulations employing floating point operations showed about the same average frame signal-to-noise ratio of about 20 dB.

• Journal of the Korea Society of Computer and Information
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• v.17 no.1
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• pp.1-10
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• 2012

Improving operating frequency of processors is no longer today's issues; a multiprocessor technique which integrates many processors has received increasing attention. Currently, high-performance processors that integrate 64 or 128 cores are developing for large data processing over 2, 4, or 8 processor cores. This paper proposes an optimal many-core processor for synthesizing guitar sounds. Unlike the previous research in which a processing element (PE) was assigned to support one of guitar strings, this paper evaluates the impacts of mapping different numbers of PEs to one guitar string in terms of performance and both area and energy efficiencies using architectural and workload simulations. Experimental results show that the maximum area energy efficiencies were achieved at PEs=24 and 96, respectively, for synthesizing guitar sounds with sampling rate of 44.1kHz and 16-bit quantization. The synthesized sounds were very similar to original guitar sounds in their spectra. In addition, the proposed many-core processor was 1,235 and 22 times better than TI TMS320C6416 in area and energy efficiencies, respectively.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.183-190
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• 2014

The purpose of this study was to examine the smoking-related characteristics of health and non-health related majors and the relationship between the smoking dependence and oral health practice of college students. The subjects in this study were the college students who were selected by convenience sampling from four different universities in the city of Jeonju, North Jeolla Province. The answer sheets from 811 respondents were analyzed. The findings of the study were as follows: The rate of the smoker students whose major was related to health stood at 20.6 percent, and that of the smoker students whose major was not related to health stood at 29.4%. There were significant differences according to the track of their major (p<0.05). As for links between smoking dependence and a plan to quit smoking, 32.7% of the health-related majors who considered themselves to depend on smoking replied they would give up smoking if there would be a rise in cigarette price (p<0.005), and 37% of the nonhealth related majors who considered themselves to depend on smoking gave the same answer. Thus, the largest group of the students intended to quit smoking if there would be a rise in cigarette price, and there were statistically significant differences according to smoking dependence (p<0.05). Concerning connections between smoking dependence and actual oral health practice, the non-health related majors who didn't consider themselves to depend on smoking got 3.53 in the item whether they brushed their teeth twice or more a day (p<0.05). In conclusion, the development and implementation of systematic programs that are to teach students to stay away from or quit smoking and take care of their oral health regardless of their major are required to step up the oral health promotion of college students.

• Journal of Korean Academy of Nursing
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• v.5 no.1
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• pp.133-143
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• 1975

Most of mothers place their babies in either supine or prone position without change of position. Studies comparing supine and prone position of the newborn infants -have already been performed with the result that the prone position is relatively better than the supine position. However, one kind of position recommended to the mothers is not sufficient for the good rearing practice of children, because the same position placed for period long of time may bring out physical, mental tension and fatigue, and deformities of the skull and the thorax. For this reason nurses have to find out other position which has identical or more advantages than prone position so as to perform the position change for the babies. Main purpose of this study is to identify the differences of vital signs, the number of urination, defecation, diaper rash, crying and amount of feeding of the newborn infants with prone position or lateral position during the first three days of life. Sixty two newborn infants who were delivered at Seoul National University Hospital during the period from July 1 to September 5, 1974 were chosen as subjects for this study. The criteria for the choice of subjects were the babies born with vaginal delivery; body weight 2.5kg or over at birth; Apgar score Seven or over; and gestation period between thirty-eight months ana forty- two months. Of these subjects, by random sampling, thirty-one newborn infants were placed in the prone position and the other thirty-one in the lateral position. The results of this study reviewed in a statistical analysis of the t-test to obtain the following findings : 1. The heart rates of babies in the prone position were the mean heart rates of 135.03 and those in the lateral position 135.98 without any statistically significant difference. 2. There was no significant difference of respiration rate between two groups : a group in the prone position showed the mean respiration rates of 45,57 and the other in the lateral position 46.49. 3. There was no significant difference of body temperature between two groups: the mean body temperature of a group placed in the prone position was 98$^{\circ}$18'F(36$^{\circ}$77'C) and that of the other group 98$^{\circ}$20'F(36$^{\circ}$78'C). 4. One baby showed diaper rash only in a group of infants in the prone position. 5. The number of crying of the babies in the prone position were 23.70 and those in the lateral position 30.00 with a statistical difference at 5 percent level. 6, There was no difference of frequency of urination between two groups: the mean frequency of a group placed in tile prone position was 5.44 and that of the other group 5.06, 7. There was no significant difference of frequency of defecation between two groups : the mean frequency of a group placed in the prone position was 4.20 and that of tile other group 4.21, 8. There was no significant difference of feeding amount between two groups : the average amount of a group in the prone position showed 325.03 and that of the other group in the lateral position 291.51. All the above results mean that we may substitute tile lateral position for the Prone position or utilize both position for tile rearing practice of the babies.

• Journal of Korean Home Economics Education Association
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• v.16 no.3
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• pp.115-129
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• 2004

We investigated the prevalence of eating disorder risk group and its relationship with Physique status and eating behavior among high school students in Daejeon. In May - June 2002, 350 students were sampled from 6 high schools in Daejeon by multi-stage cluster sampling and assessed with self-completing questionnaires. We used the Korean version of Eating Attitude test(EAT-26) to screen eating disorder risk group. and other instruments to screen physique status and eating behavior. The response rate was 91%(total 320) and numbers of female students were 167(52.2%) and male students were 153(47.8%). Average age was 16.0${\pm}$0.35 years, and average body-mass index(BMI) and PIBW(Percent Ideal Body Weight) were 20.9${\pm}$3.3 Kg/m2 and 102${\pm}$4.2% in male students, 20.2${\pm}$3.7 Kg/m2 and 98${\pm}$7.2% in female students(p<0.0001). Over 50% of the subjects were dissatisfied with their body shape; the degree of dissatisfaction with body shape was higher in those who believed themselves to be fat. Mean score of EAT-26 was higher in female students (10.78${\pm}$7.36) than male students(6.07${\pm}$4.39)(p<0.0001). The prevalence of high risk eating disorder group was 2.6% in male students, 11.4% in female students(p<0.0001). Eating behavior was better in female students than male(p<0.0001). Eating behavior was significantly higher in eating disorder risk group in both sex. Therefore eating disorder symptomatology was highly prevalent among high school students in Daejeon. And this symptomatology has a more close relationship with physique status and eating behavior in female students.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.4
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• pp.53-63
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• 2009

This work proposes a 10b 100MS/s 27.2mW $0.8mm^2$ 0.18um CMOS ADC for WLAN such as an IEEE 802.11n standard. The proposed ADC employs a three-stage pipeline architecture and minimizes power consumption and chip area by sharing as many circuits as possible. Two multiplying DACs share a single amplifier without MOS switches connected in series while the shared amplifier does not show a conventional memory effect. All three flash ADCs use only one resistor ladder while the second and third flash ADCs share all pre-amps to further reduce power consumption and chip area. The interpolation circuit employed in the flash ADCs halves the required number of pre-amps and an input-output isolated dynamic latch reduces the increased kickback noise caused by the pre-amp sharing. The prototype ADC implemented in a 0.18um n-well 1P6M CMOS process shows the DNL and INL within 0.83LSB and 1.52LSB at 10b, respectively. The ADC measures an SNDR of 52.1dB and an SFDR of 67.6dB at a sampling rate of 100MS/s. The ADC with an active die area of $0.8mm^2$ consumes 27.2mW at 1.8V and 100MS/s.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.495-503
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• 2006

The purpose of this study was to analyze the effect of the consumer-brand relationship quality on the brand loyalty in family restaurants. Questionnaires were distributed to 320 students in K University located in Masan, who were sampled by convenience-sampling method. The surveys were conducted from November, 10 to 24, 2005. Of the 287 returned questionnaires, 15 unusable questionnaires were excluded to leave 272 for use in the final analysis(response rate: 85.0%). For the statistical analysis, SPSS(12.0)was used to conduct the descriptive analysis, factor analysis, reliability analysis, correlation and multiple regression analysis. The results of this study showed that 2 constructs (satisfaction and intimacy) of consumer-brand relationship quality have significantly positive effects on the brand loyalty in family restaurants(p<.01). This indicates that as consumer-brand relationship quality strengthens, the customer's brand loyalty increases. In conclusion, food service managers in family restaurants should focus on the marketing strategies to strengthen the quality of consumer-brand relationship in order to increase the brand loyalty of customers.