• Journal of Korea Foundry Society
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• v.28 no.1
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• pp.37-40
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• 2008

본 연구는 ADI의 기계적 성질을 개선하고자 오스테나이트화 과정에서 초기 변태온도를 $900^{\circ}C$ (${\gamma}$ 구역)에서 시작하여 $800^{\circ}C$까지(${\alpha}+{\gamma}$ 구역) 일정한 냉각제어에 의해 오스템퍼링을 한다. 여기서 Full ADI에서 생성되는 고탄소 오스테나이트 조직을 저탄소 오스테나이트로 유도하고 미세한 침상의 Full ADI조직을 연성이 높은 조대한 아공석 페라이트 조직이 생성되도록 하여 Semi ADI를 만든다. Full ADI와 Semi ADI의 기계적 성질 및 피로강도를 연구한 결과 Full ADI와 Semi ADI의 정적강도는 유사하지만, 피로강도는 Semi ADI의 기지조직의 변화에 기인하여 Full ADI보다 피로강도가 높게 나타났다. 이러한 현상은 Semi ADI의 조대한 페라이트가 균열개구 저항력이 낮아 초기에는 쉽게 개구되지만, 균열개구와 동시에 균열선단에서 큰 소성역이 발생되어 균열성장이 지연하는 효과로 판단된다.

• Imaging Science in Dentistry
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• v.38 no.4
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• pp.189-194
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• 2008

Picture archiving and communication system (PACS) is an image information technology system for the transmission and storage of medical images. In Korea the first full PACS was installed at Samsung Medical Center in 1994, but, the rate of distribution was very slow. The government's approval for the medical insurance reimbursement for full PACS examinations in November 1999 became the turning point. Thereafter the number of hospitals with full PACS has steeply increased. In September of this year, PACS was installed at 906 medical institutes, including most of university hospitals and general hospitals. The first full dental PACS was installed at Wonkwang University Dental Hospital in 2002. Now ten out of eleven university dental hospitals implemented full dental PACS. The current status and technological factors of dental PACS in Korean university dental hospitals and the future perspectives of dental PACS are described. (Korean J Oral Maxillofac Radiol 2008; 38: 189-94)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.445-455
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• 2017

This study was conducted to identify the relevance between postpartum women'sfatigue and breast-feeding rate in accordance with the types of rooming-in care at one hospital in Seoul. The data were collected by using a self-report questionnaire between June and July of 2014. All subjects were full-time rooming-in group, with 64 mothers and part time rooming-in group, 43 mothers. The collected data were analyzed using SPSS 22.0 windows program. The result supported Hypothesis 1, in which the number of full-time rooming-in group's daily breast-feeding would out number that of part time rooming-in group. Hypothesis 2, on the other hand, which was that the breast-feeding rate would differ between the full-time rooming-in and the part-time rooming-in groups was overruled. Hypothesis 3, in which the fatigue of the full-time rooming-in group would be higher than the part-time rooming-in group was supported. Hypothesis 4, in which postpartum women'sfatigue would relate to breast-feeding rate during hospitalization period was overruled. Thus, based on this research, it is suggested that rather than collectively running the full-time rooming-in care, part-time rooming-in care that is individualized with considerations to the conditions of the mothers and new-born should be considered.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.13-17
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• 1993

This study was conducted to determine the cost of production of semen and the rate of conception for artificial insemination in eight randomly selected districts of Bangladesh. A sample of 640 adopting farms were investigated. Results indicate that the cost of liquid semen per dose on full-cost and cash cast basis were Tk. 16.17 and Tk. 14.48, while the cost of locally produced exotic semen and imported semen were Tk. 31.25 and Tk. 110.00 respectively. The cost of liquid semen per insemination, per conception and per progeny on full-cost were Tk. 26.65, Tk. 50.64, and Tk. 56.27 respectively and on cash cost were Tk. 23.88, Tk. 45.37 and Tk. 50.41 respectively. The average cost of semen paid by the farmers was Tk. 14.00 and it was higher in urban areas than in rural areas. Out of the cost of A.I. centres, government had subsidized 92.16 percent and the rest 7.84 percent accrued as returns. About 40 percent of the produced semen was lost in the system which could not be used at all. The conception rate on first insemination was 53.6 percent. The rate increased to 73.2 percent upto the last insemination. The difference in conception rate between liquid semen (69.97%) and frozen semen (70.48%) was not statistically significant.

• Journal of Korean society of Dental Hygiene
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• v.24 no.2
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• pp.163-174
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• 2024

Objectives: This study aimed to understand the knowledge, attitude, and wearing of four types of personal protective equipment among dental hygienists based on to the COVID-19 infection control guidelines and to provide basic data on the need to wear these equipment by dental hygienists in dental medical institutions. Methods: Between March 31 and April 26, 2022, 285 dental hygienists working at dental institutions in Busan and Gyeongsang Provinces participated in the study. Results: The higher the knowledge on personal protective equipment, the higher the glove-wearing rate; and the higher the attitude toward personal protective equipment, the higher the KF94 mask-wearing rate. Furthermore, the higher the rate of wearing face shields, the higher the rate of wearing gloves and full-body protective suits; and the higher the rate of wearing gloves, the higher the rate of wearing a full-body protective suit. Conclusions: To prevent cross-infection by dental hygienists in dental medical institutions, it is necessary to have the four types of personal protective equipment at all times and to strengthen comprehensive education on these equipment

• Women's Health Nursing
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• v.9 no.3
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• pp.224-234
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• 2003

Purpose: This study was to test the effects of a full body massage on labor pain and delivery stress reaction for primipara during labor. Method: This study employed a quasi- experimental method(nonequivalent control group, pre-post test design). The subjects of this study were 57 primipara hospitalized at the U OB & GYN hospital in Inchon from November 1. 2001 to July 31, 2002. 28 women were assigned to the experimental group and 29 to the control group. The experimental group was given 20 minutes full body massage for each of three delivery phases. The control group was given conventional delivery care. The levels of labor pain were measured by the Visual Analogue Scale and the expression scores of the labor pain and the levels of delivery stress reaction were measured by pulse rate, respiration rate, and blood pressure, and State-Anxiety Scale. Data were analyzed using the repeated measures analysis of covariance(ANCOVA), t-test, $X^2$- test, simple ANCOVA with SPSS program. Result: There was no interaction effect between time and group(F=.370, p=.693), but significant time effects were found for subjective labor pain(F=3.840, p=.028). There was no interaction effect between time and group(F=.112, p=.894), but significant group effects were found for objective labor pain(F=12.299, p=.001). There was no interaction effect between time and group for PR(F=.172, p=.843), RR(F=.626, p=.539), SBP(F=.089, p=.915), DBP(F=.748, p=.479), but significant group effects were found for SBP(F=7.547, p=.008). The level of status anxiety of the experimental group was significantly lower than the control group(F=11.787, p=.001). Conclusion: This study showed that the full body massage has partially positive effect on labor pain and delivery stress reaction. Therefore this study suggested that the full body massage might be used clinically to help primipara during labor.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.12
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• pp.2353-2362
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• 2015

In this paper, we employ the single channel full duplex radio for wireless local area network (WLAN) systems, and design digital interference cancellers using adaptive signal processing. When the full duplex scheme is used for WLAN systems with multiple transmit and receive antennas, some interference is caused through the feedback of transmit signals from multiple antennas. To remove the feedback interference, we derive the least mean square (LMS), normalized LMS (NLMS), and recursive least squares (RLS) algorithms based on adaptive signal processing techniques. In addition, we analyze the theoretical convergence of the proposed LMS and RLS methods. The channel capacity of full duplex radios increases by two times than that of half duplex radios, when the packet error rate (PER) performances for the two systems are identical. Through numerical simulations in WLAN systems, it is shown that the full duplex method with the proposed interference cancellers has a similar PER performance with the conventional half duplex transmission scheme.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.373-374
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• 2006

JPEG2000 achieves a target bit rate by selecting the bitstream for adequate coding passes after encoding full passes in Tier-1 coder. Tier-1 encoding is complicated and time-consuming process. In this paper, we propose a new rate control technique that chooses the necessary passes without the full passes coding of Tier-1 by using previous image information for volumetric image. The simulation result shows that the proposed technique reduces encoding time of coding passes up to 81.5%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.507-513
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• 2015

In this paper, we present the bit-error rate (BER) performance of quasi-orthogonal space-time block code (QOSTBC) massive multiple-input multiple-output (MIMO) system employing up to 32 transmit and receive antennas. The QOSTBC, due to its advantages in transmission rate and decoding complexity, is an important transmit diversity scheme for more than 2 transmit antennas. As massive MIMO implies very large number of antennas, practically at least more than 15 antennas, a different number of transmit and receive antennas (i.e. $2{\times}2$, $4{\times}4$, $8{\times}8$, $16{\times}16$ and $32{\times}32$) using QOSTBC for the massive MIMO system are considered. The BER performance of the massive MIMO with antennas up to $32{\times}32$ using BPSK modulation scheme is analyzed. Simulation results show that the full-rate massive MIMO systems with QOSTBC give a significant performance improvement due to increasing diversity effect, compared with previously considered massive MIMO systems.

• Journal of IKEEE
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• v.23 no.4
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• pp.1218-1223
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• 2019

In HVDC systems, the full-bridge submodule increases the number of components compared to the half-bridge submodule, but the failure-rate can be reduced by securing 100 % redundancy. However, full-bridge submodules require more complex control algorithms to ensure the redundancy and to prevent arm-short with sufficient dead-time. To solve this problem, we analyse the failure-rate of the paralleled half-bridge configuration with the same number of components and 100 % redundancy as the full-bridge submodule. The fault tree analysis (FTA) method is applied to the conventional part failure analysis to reflect the operation risk of the submodule, thereby predicting the life-cycle of the submodule more accurately. To verify the validity, the failure-rate results of the proposed FTA based analysis method are compared with the failure rate obtained by the part failure method.