• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.94-101
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• 1977

Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard -one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefor, we must establish an enactment to control mechanical noise sources. as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time. The sample size of this study was 74 machines at 11 plants in 6 industries. The results are as follows; 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with $103.8{\pm}2.8dB(A)$, and lowest in the textile industry, with $89.2{\pm}1.43dB(A)$. 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Chack) (I) in the timber industry. 4. The shortest permissible exposure time to Gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz, 4.1% at 4 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels were increased without any change of the frequency of the peak sound. 8. Whenever the machines had the same kind and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.

• Korean Business Review
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• v.11
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• pp.277-293
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• 1998

The purpose of this study is to analyse the overall relationship between the advertisement expenses and the two major indicies of business performance, that is, the total amount of sales and the discipline have contrasted the expenses for commercial advertisement with the total amount of sales or with the business performance, respectively, utilizing data on a specific product observed through 3 to 5 years. This study attempts to enlarge the scope of observation and the content of analysis. In order to attain the purpose of this study, the rate of increase in the advertisement expenses is taken as the independent variable and the two major indicies of business performance, the total amount of sales and the resultant interest, as the dependent variables. Business companies or firms which have continually been listed on the board of Korea Stock Exchange for 14 years, from 1982 to 1995, were grouped into four major business categories; 1)Food and beverage industries, 2)Fiber, clothings, and leather industries, 3) Medicine, chemistry, oil, coal, and rubber industries, and 4) Assembled mechanics and metallurgy, machinery, and maintenance industries. Utilizing the KIS-DATA, compiled by Korea Credit Evaluation, Ltd., 30 to 40 samples of business companies or firms were randomly selected from each category. Finally 125 samples were selected and put into regression analyses and follow-up tests by appropriate statistical models, in order to verify if there were any noticeable correlations. The final result obtained through the afore-mentioned research method shows that the amount of advertisement expenses has strong correlations with the amount of sales and the resultant interest. Viewed by business category, in the case of fiber, clothings, and leather industries, the relationship turned out to be significant only with the rate of increase in the total amount of sales, while, in the case of food and beverage industries, the rate of increase in the total amount of sales showed a negatively significant correlations.

• Proceedings of the ESK Conference
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• 1993.10a
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• pp.65-75
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• 1993

원자력발전소에서 발생하는 고장정지 사건에 내포된 인적오류의 발생내용을 흥미있고 현장감 있게 묘사시킴과 동시에 종사원들의 인적오류를 저감시키기 위한 새로운 교육훈련방 법으로써 멀티미디어 기술의 사용을 고려하였다. 즉, 컴퓨터 환경하에서 숫자와 텍스트, 음 향 및 음성, 그래픽, 애니메이션, 화상 등의 미디어를 사용하여 인적오류로 인한 고장정지 사건발생의 내용을 전달하는 새로운 교육훈련 방법을 사용하는 것이다. 이를 위하여 고장정 지 사건과 관련한 원자력발전소 구성정보와 종사원의 활동정보를 입출력하기 위한 멀티미디어 인터페이스를 설계하였다. 설계는 멀티미디어 제공환경 구축과 인터페이스 운영논리 설정의 두단계로 구성한 절차에 따라 수행하였다. 멀티미디어 인터페이스는 원자력발전소 구성정보를 설계하여 저장시켜둔 퍼스널 컴퓨터 환경하에서 운영되며, 입력 및 출력의 두가지 인터페이스 를 갖는다. 입력 인터페이스는 인적 오류를 포함한 고장정지 사건의 발생내용을 숫자, 텍스트, 음성 미디어로 받아들여 출력 인터페이스에서 사용될 수 있도록 미디어 결합을 수행하고, 컴퓨터 저장장치에 저장하는 기능을 수행한다. 출력 인터페이스는 저장장치에 기록된 내용을 판독하여 고장정지의 진행경위와 인적오류의 발생내용을 숫자, 문자, 텍스트, 음성, 음향, 그래픽 애니메 이션, 정지화상으로 원자력발전소 종사원들에게 출력시켜 주는 기능을 수행한다. 멀티미디어 출력정보는 사용자가 CRT 화면에 제공되는 버튼 또는 Click Touch 메뉴를 사용함에 따라 이전, 이후의 출력정보로 전이할 수 있도록 하였다.상대적으로 중요한 검사 항목으로 나타났다. 또한 상대적 중요도 결과를 적용한 적성검사 성적이 적용하지 않은 적성검사 성적에 비해 비행성적에 대한 예측 능력이 좋은 것으로 평가되었다.al age)가 있다는 것을 의미하는 것이다. 한편, 생산현장에서는 자동화, 기계화가 진보되어 육체적인 노동이 경감된 결과, 중고령자라도 할 수 있는 작업이 많아지고 있다. 또, VDT (Visual Dislay Terminal) 작업과 같은 정보처리 작업의 수요가 증가하여 그 인재의 부족이 지적되고 있다. 따라서 중고령자의 기능을 조사하여 어떠한 작업에 적합한가를 판단하는 것이 중요한 과제로 되었다. 그러나 노동에는 많은 기능이 관여 하고, 그 내용에 따라서 요구되는 기능이 서로 다르기 때문에 노동적응능력의 기본적인 기능으로 보여지는 것에 좁혀서 작업능력의 연령증가 변화에 대하여다원적 평가를 하는 것이 실제적이라고 할 수 있다. 따라서 본 연구에서는 인간이 가지고 있는 다수의 기능중에서 수지교 치성과 연령증가와의 관계를 조사한다. 만약 연령증가 만으로 수지교치성을 평가 할 수 없는 경우에는 어떠한 요인이 수지기민성의 변화에 영향을 미치는가를 검토한다.t list)에서 자동적으로 사건들의 순서가 결정되도록 확장하였으며, 설비 제어방식에 있어서도 FIFO, LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등

• Food Engineering Progress
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• v.22 no.4
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• pp.381-385
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• 2018

Various rheological methods to measure the hardness of instant cooked rice by a texture analyzer were investigated and compared. Specifically, instant white rice samples with a wide range of hardness were subjected to four different rheological tests with disk, cylinder, rod, and cone probe whose results were inter-correlated. All the measurements demonstrated that the hardness of instant rice was reduced with increasing moisture content and showed negatively linear relationships. Out of the four tests applied in this study, the highest coefficient of correlation ($R^2=0.9268$) was observed distinctly in the cone probe test, where both compressive and shear forces can be applied to deform individual rice grains. However, the cylinder probe test had the lowest coefficient of correlation ($R^2=0.7247$) because it may be ineffective in causing direct deformation of individual rice grains. Furthermore, when the hardness values (N) were converted to stress (Pa), highly linear correlations ($R^2{\approx}0.99$) were observed between the tests with similar probe geometry and force application.

• The Journal of the Acoustical Society of Korea
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• v.40 no.1
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• pp.46-54
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• 2021

In this paper, active noise control was performed to reduce radiated noise in the low frequency band of dishwashers. First, through an analysis of the noise environment of the dishwasher, it was confirmed that the pump noise contributed the most to the radiated noise in the low frequency band, From the result of the noise environment analysis, the reference signal was selected to be the vibration signal of the pump body. The reference signal was obtained by using the accelerometer on the pump body, which can prevent acoustic feedback. The error signal sensor was selected as a microphone located at 1 m in front of the dishwasher and 0.5 m in height. And to design the controller, the error signal and the reference signal were measured at the operational rpms of the dishwasher at 2,500 rpm, 2,600 rpm and 2,800 rpm, and the secondary path transfer function was measured. The designed controller was mounted on Digital Signal Processor (DSP) equipment, and the control performance was verified experimentally. As a result of the measurement at the 3 operational rpms, the 7th multiple component of pump operating frequency decreased by 1.93 dB, 4.43 dB, 5.15 dB per rpm, and the 12th multiple component decreased by 6.67 dB, 2.34 dB, 4.28 dB per rpm. And overall Sound Pressure Level (SPL) decreased by 0.84 dB, 2.58 dB, 1.48 dB by rpm.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.1
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• pp.81-98
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• 2024

This study analyzed the impact of urban spatial factors on the thermal environment. The personal thermal sensation was set as the unit of thermal environment to analyze its correlation with environmental factors. To collect data on personal thermal sensation, Living Lab was applied, allowing citizens to record their thermal sensation and measure the temperature. Based on the input points of the collected personal thermal sensation, nearby urban spatial elements were collected to build a dataset for statistical analysis. Logistic regression analysis was conducted to analyze the impact of each factor on personal thermal sensation. The analysis results indicate that the temperature is influenced by the surrounding spatial environment, showing a negative correlation with building height, greenery rate, and road rate, and a positive correlation with sky view factor. Furthermore, the road rate, sky view factor, and greenery rate, in that order, had a strong impact on perceived heat. The results of this study are expected to be utilized as basic data for assessing the thermal environment to prepare local thermal environment measures in response to climate change.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.437-443
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• 2001

Gastrodia elata blume (GEB) is considered to be a useful herbal medicine in oriental countries for the treatment of headache, migraine, dizziness, childhood convulsion, epilepsy, rheumatism, hypertension, neuralgia and neurological disorders. This study was carried out to investigate the quality of bread added with the powder of GEB. The possibility of GEB wheat flour mixture as bread was studied by adding 0%, 0.5%, 1.0%, 1.5%, 2.0% of GEB powder to wheat flour. In Farinograph data, the dough stability decreased with the increase of GEB powder. Granular size of starches ranged from $36\;{\mu}m\;to\;60{\mu}m$, and the shape of them showed a long oval figure. Amylograph showed that the increase in the ratio of GEB on the doughs slightly elevated in the maximum viscosity. The loaf volume of 0.5% powder increased by 10.2% but that of 2.0% decreased by 16.8%. The moisture content was 43.57% in the control but it increased as the powder addition. The colors of crust and crumb were not significantly different among L, b and ${\Delta}E$, but 'a' value in crumb was increased as the powder addition. The addition of the powder had no significant effect on bread texture. In sensory evaluation, the moistness increased as the increase of the powder addition. The control bread was most excellent, and the bread made by mixing additives were better than just 0.5% GEB-wheat flour in terms of quality.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.385-392
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• 2004

Physicochemical and sensory characteristics of commercial Oiji, Korean pickled cucumbers (six commercial and three traditionally made products) were investigated. Saltiness values for commercial and traditionally made products were 3.424-4.47 and 3.92-7,23%, and acidity and pH were 3.43-3.85 and 0.39-0.75%, respectively, Commercial products showed lower L and higher b values than traditionally made products. Redness of both products ranged from -1.47 to -3.71. Numbers of total microbial, lactic acid bacteria, and yeast in traditionally made products ($1{\times}10^{7}-1.3{\times}10^{9},\;4{\times}10^{6}-4.7{\times}10^{8},\;and\;1.3{\times}10^{6}-3{\times}10^{8}\;cfu/mL,\;respectively$), were higher than those of commercial products ($1{\times}10^{4}-2{\times}10^{7},\;1{\times}10^{4}-6{\times}10^{6},\;and\;1{\times}10^{4}-6{\times}10^{6}cfu/mL\;respectively$). Texture analysis revealed fracturability (2,103-3,010 g) and hardness (409-890 g) varied among the products above. Overall acceptability scores of commercial products C1 and C2 were highest at 7.6-8.0 compared to other products (p<0.05). From the principal component analysis, the first principal component (PC1, 79.94%) and the second principal component (PC2, 19.94%) could describe the majority of the variability. Commercial product C1, C2, C3, and C7 having high negative loadings on the PC2 axis are closely related to over-all acceptability, over-all taste, savory taste and hardness. From Pearson correlation analysis, hardness and chewiness correlated positively with saltiness, whereas over-all acceptability, positively correlated with savory and overall taste, respectively (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1433-1438
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• 2013

In this study, we have investigated the quality characteristics of Tteokgukdduk, a traditional Korean rice cake, containing different amounts of mugwort powder (0, 1, 3, 5, 7 w/w %). We observed that the moisture content in Tteokgukdduk containing mugwort powder ranged at 41.79 to 42.50% was not significant when compared with Tteokgukdduk that is devoid of mugwort powder. We also noted that the Hunter color L value decreased in proportion to the added mugwort powder. Further, the weight of Tteokgukdduk was found to be increased with increasing levels of added mugwort powder. However, the volume of Tteokgukdduk did not varied significantly at the different mugwort powder concentrations (P>0.05). We also observed that the hardness of uncooked Tteokgukdduk containing 3% mugwort powder showed the lowest value among Tteokgukdduk containing mugwort powder. However, it did not varied significantly at the different mugwort powder concentrations (P>0.05). In cooked Tteokgukdduk, however, we found that the nature and quality of springiness and gumminess increased with corresponding increase in the amount of added mugwort powder. Further, with regard to the sensory evaluation, the intensity (of both color and flavor) of Tteokgukdduk was found to be increased with proportionate increase in the amount of added mugwort powder. The results of this study suggest that the acceptability qualities such as color, flavor, taste, texture, and overall acceptability were of the highest order for Tteokgukdduk containing 3% mugwort powder.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.427-436
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• 2004

The current study was conducted to determine the effect of suspension method on satisfaction level of Korean consumers and objective meat quality traits in Hanwoo longissimus dorsi(LD), triceps brachii(TB) and semimembranosus(SM) muscles. Eighteen Hanwoo steers were slaughtered and alternative sides were hung either by pelvic bone(TS) or Achilles tendon(Al). Sensory characteristics, WB-shear force, sarcomere length, water-holding capacity, saroomere length and cooking loss were determined after a 7-d chiller ageing. Higher carcass quality grade received significantly(p < 0.05) greater eating quality for LD, but the grade did not affect eating quality for both TB and SM. TS did not influence objective and subjective meat quality for TB, but that significantly(P < 0.05) improved eating quality for LD and SM. The most noticeable result was that when SM was tenderstretehed, eating quality was equivalent to that of nonna1ly hung LD. In relationship between objective and subjective meat quality assessments, eating qualty for LD had a significant(P < 0.05) relationship with intramuscular fat content, while that for SM was greatly(P < 0.05) related to saroomere length. The current study indicated that pelvic hanging was an effective way to improve eating quality both LD and SM, and carcass quality grades did not greatly reflect eating quality of SM and TB. The data also implied that instnunental measurements poorly estimated the satisfaction level of Korean conswners.