• Design & Manufacturing
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• 제18권2호
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• pp.23-28
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• 2024

The automobile industry is a wide range of related industries, including parts manufacturing and vehicle assembly, press processing is an essential element in making automobiles. Press processing is a processing method for metal sheets that has relatively high dimensional and shape precision and is suitable for mass production. It refers to processing by attaching a special tool, a mold, to a press machine. Recently, the automobile industry is attempting to reduce the weight of automobiles in order to reduce carbon emissions due to global warming, and the use of high-strength steel sheets, which are lighter than general structural steel sheets, is a natural trend. Shear processing is required to use high-strength steel, and the shape of the shear surface created by shear processing has a significant impact on the quality of the automobile. Therefore, various methods are being attempted to improve the share surface during shear processing. Among them, shaving processing is a method of shearing the primary shearing area again, and it is difficult to obtain an accurate answer because complex deformation occurs in the microscopic shear area. Therefore, in this study, the effect of machining allowance on shaving processing was analyzed using the finite element method using high-strength steel plate (SPFH590), and the differences were compared and examined through actual experiments under the same conditions.

• 한국수산과학회지
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• 제12권2호
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• pp.103-111
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• 1979

우리나라 연안수산자원의 효율적인 이용방법을 개발할 목적으로 축육과 유사한 가공적성을 가지는 새로운 형태의 어육단백질농축물을 가공하기 위한 기초자료를 얻고자 백색육어인 명태와 적색육어인 고등어를 원료로 하여 최적가공조건 및 제품의 품질에 관하여 실험하였다. 명태 및 고등어로써 어육단백질농축물을 제조할 때의 최적가공조건은 다음과 같았다. 원료어육의 pH는 7.5, 고기풀제조시의 식염첨가량은 원료어육 중량에 대하여 $1.0\%$, 압출기로 압출한 고기풀의 에틸알코올중 침지시간은 40분, 침지시의 에틸알코올 량은 어육량에 4배, 그때의 에틸알코올 온도는 낮은 온도가 적당하였으며, 에틸알코올중의 침지회수는 4회가 적당하였고, 에틸알코올을 제거하는데는 냉풍건조가 효과적이었다. 원료어육에 대한 제품의 수율은 명태와 고등어가 각각 $19.9\%$ 및 $29.8\%$ 였다. 제품의 단백질함량은 명태가 $84.3\%$, 고등어가 $78.1\%$였으며, 지방함량은 각각 $0.5\%$ 및 $3.6\%$였다. 명태 및 고등어 조직단백질농축물의 필순 아미노 산조성은 우육, 대두조직단백질 및 FAO 표준치와 비교하였을 때 손색이 없었으며, 두 제품 모드 우육과 1:1의 중량비로 혼합하여 맛, 색, 촉감에 손색없이 식품소재로 이용할 수 있다는 결론을 얻었다.

• Safety and Health at Work
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• 제8권4호
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• pp.386-392
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• 2017

Background: Fire service workers often implement multiple duties in the emergency conditions, with such duties being mostly conducted in various ambient temperatures. Methods: The aim of the current study was to assess the firefighters' physiological responses, information processing, and working memory prior to and following simulated firefighting activities in three different hot environments. Seventeen healthy male firefighters performed simulated firefighting tasks in three separate conditions, namely (1) low heat (LH; $29-31^{\circ}C$, 55-60% relative humidity), (2) moderate heat (MH; $32-34^{\circ}C$, 55-60% relative humidity), and (3) severe heat (SH; $35-37^{\circ}C$, 55-60% relative humidity). It took about 45-50 minutes for each firefighter to finish all defined firefighting activities and the paced auditory serial addition test (PASAT). Results: At the end of all the three experimental conditions, heart rate (HR) and tympanic temperature (TT) increased, while PASAT scores as a measure of information processing performance decreased relative to baseline. HR and TT were significantly higher at the end of the experiment in the SH ($159.41{\pm}4.25beats/min$; $38.22{\pm}0.10^{\circ}C$) compared with the MH ($156.59{\pm}3.77beats/min$; $38.20{\pm}0.10^{\circ}C$) and LH ($154.24{\pm}4.67beats/min$; $38.17{\pm}0.10^{\circ}C$) conditions (p < 0.05). There was no significant difference in PASAT scores between LH and MH (p > 0.05). Nonetheless, there was a measurable difference in PASAT scores between LH and SH (p < 0.05). Conclusion: These consequences demonstrate that ambient temperature is effective in raising the physiological responses following firefighting activities. It is therefore argued that further increase of ambient temperature can impact firefighters' information processing and working memory during firefighting activity.

• 한국식품과학회지
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• 제14권1호
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• pp.36-42
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• 1982

말쥐치(Novodon modestus) 및 도루묵(Arcotoscopus japonicus)을 원료로써 축육과 유사한 어육단백질농축물을 가공하기 위한 최적조건을 검토하였다. 말쥐치를 원료로 하였을 때, 고기풀의 pH 8.0, 식염첨가량 1%, 고기풀에 대하여 3배량의 $25^{\circ}C$ 에탄올에 15분간 침지처리한 다음 다시 2배량의 비등 에탄올에 15분간 2회 침지처리하는 것이 좋았다. 도루묵의 경우는 pH 및 식염첨가량은 말취지와 같고 4배량의 $25^{\circ}C$ 에탄올에 15분간 침지처리하고, 다시 4배량의 비등 에탄올에 25분간 4회 침지처리하는 것이 좋았다. 이와같은 최적조건하에서 만든 말취지 및 도루묵의 축육과 비슷한 조직단백질 농축물 제품의 수분은 각각 9.7%, 9.5%, 단백질은 각각 84.5%, 84.2%, 지질은 각각 0.2%, 1.1%였으며, 수율은 각각 13.7%, 12.5%였다. 그리고 제품 중의 필수아미노산함량은 쇠고기 및 대두단백질과 비교하였을 때 큰 손색이 없었다.

• Clinical and Experimental Otorhinolaryngology
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• 제11권4호
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• pp.267-274
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• 2018

Objectives. Two main digital signal processing technologies inside the modern hearing aid to provide the best conditions for hearing aid users are directionality (DIR) and digital noise reduction (DNR) algorithms. There are various possible settings for these algorithms. The present study evaluates the effects of various DIR and DNR conditions (both separately and in combination) on listening comfort among hearing aid users. Methods. In 18 participants who received hearing aid fitting services from the Rehabilitation School of Shahid Beheshti University of Medical Sciences regularly, we applied acceptable noise level (ANL) as our subjective measure of listening comfort. We evaluated both of these under six different hearing aid conditions: omnidirectional-baseline, omnidirectional-broadband DNR, omnidirectional-multichannel DNR, directional, directional-broadband DNR, and directional-multichannel DNR. Results. The ANL results ranged from -3 dB to 14 dB in all conditions. The results show, among all conditions, both the omnidirectional-baseline condition and the omnidirectional-broadband DNR condition are the worst conditions for listening in noise. The DIR always reduces the amount of noise that patients received during testing. The DNR algorithm does not improve listening in noise significantly when compared with the DIR algorithms. Although both DNR and DIR algorithms yielded a lower ANL, the DIR algorithm was more effective than the DNR. Conclusion. The DIR and DNR technologies provide listening comfort in the presence of noise. Thus, user benefit depends on how the digital signal processing settings inside the hearing aid are adjusted.

• 한국약용작물학회지
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• 제18권2호
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• pp.98-104
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• 2010

Eleuthero(Eleutherococcus senticosus Maxim.) cortex is well known as a herb medicine for tonic. This study was performed to improve the quality of dried E. senticosus cortex. Investigation of quality factor and contents of efficient compounds under different steaming times and drying methods were performed to determine the proper processing and drying conditions of Eleuthero cortex harvested on March in annual stems. The proper steaming time for peeling bark to make high quality Eleuthero cortex took less than 20 mins. Eleutheroside B and E contents among drying methods were significantly different at 5% level DMRT. The $50^{\circ}C$ heat drying was the most advisable condition for drying, when drying and keeping contents of effective compounds.

• 소성∙가공
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• 제30권1호
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• pp.22-26
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• 2021

The present study demonstrated the effects of processing variable and alloying elements on the processing window of austempered cast iron, one of the heat-treatable cast irons, in order to elucidate the relation between heat treatment and microstructure in terms of time and temperature. Such microstructure is strongly affected by austenitizing conditions and alloying elements. The size of processing window tends to increase initially with increasing austenitizing temperature from 1123 to 1173 K, followed by a decline in the reverse direction between 1173 and 1223 K. Thus, the optimized processing window with large frame was found at an austenitizing temperature of 1173 K. To determine the effect of Sn addition, the processing window in the sample was created by the addition of 0.08 wt.% Sn, which appeared larger than that without Sn and with 0.06 wt.% Sn.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권2호
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• pp.103-110
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• 2005

Broken rotor bars in induction motors can be detected by monitoring any abnormality of the spectrum amplitudes at certain frequencies in the motor current spectrum. Broken rotor bar fault detection schemes should rely on multiple signatures in order to overcome or reduce the effect of any misinterpretation of the signatures that are obscured by factors such as measurement noises and different load conditions. Multiple Discriminant Analysis (MDA) and Artificial Neural Networks (ANN) provide appropriate environments to develop such fault detection schemes because of their multi-input processing capabilities. This paper describes two fault detection schemes for broken rotor bar fault detection with multiple signature processing, and demonstrates that multiple signature processing is more efficient than single signature processing.

• 한국레이저가공학회지
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• 제4권2호
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• pp.29-38
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• 2001

A development of in-process and reliable monitoring system in laser materials processing is essential for successful applications toward the real industrial fields. It was known that optical signals induced by laser-matter interactions provide a good indication not only to monitor various defects but also to characterize and identify the process However there are still difficulties to implement the optical monitoring system in real fields since the system is susceptible to the spurious change of the signal affected by the variation of experimental conditions and environmental noises. In this article. a new type of optical monitoring technique named 'chromatic modulation technique' is described as a reliable, robust and sensitive monitor for the applications in laser materials processing in order to tackle the conventional problems in optical system.

• 한국축산시설환경학회지
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• 제5권3호
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• pp.139-148
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• 1999

This study was conducted to develop an image processing system which can classify the pig's thermoregulatory behavior under the different environmental conditions. The 4 pigs of 25kg were housed in the environmentally controlled chamber(1.4m$\times$2.2m floor space). Postural behavior of the pigs was captured with an CCD color camera. The raw behavioral images were processed by thresholoding, reduction, separation of slightly contacted pigs, labeling, noise removal, computation of number of labels, and classification of the pig's behavior. The correct classification rate of the image processing system was 97.8%(88 out of 90 testing images). The results of this study showed that the image processing system could be used for a behavior-based automatic environmental controller.