• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.2
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• pp.128-136
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• 1995

The purpose of this study is to evaluate the difference of noise level according to noise measuring methods in the noisy working environments. Sound pressure level(SPL), equivalence sound level(Leq) and personal noise exposure dose(Dose) in the fifty-nine unit workplaces of the twenty-eight industries were measured and relating factors which were affected noise level were investigated. The results were as follows ; 1. The noise levels were $88.70{\pm}5.68dB(A)$ by SPL, $89.07{\pm}5.41dB(A)$ by Leq and $89.07{\pm}5.69$ by Dose. The differences of noise levels by three measuring methods were statistically significant(P<0.001) by repeated measure ANOV A. 2. Comparing with noise levels by general classes of noise exposure, noise levels of continuous noise were $89.14{\pm}5.19dB(A)$ by SPL, $89.45{\pm}4.65dB(A)$ by Leq and $90.04{\pm}5.09$ by Dose. Noise levels of intermittent noise were $87.90{\pm}6.52dB(A)$ by SPL, $88.40{\pm}6.63dB(A)$ by Leq and $90.10{\pm}6.80$ by Dose. The differences noise level of noise measuring methods by general classese of noise exposure were statistically not significant by repeated measure ANOV A. 3. Interaction between general classese of noise exposure and noise measuring methods for noise level was not statistically significant by repeated measure ANOVA. And the noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001) 4. Comparing with noise levels by unit workplace size, noise levels of large unit workplace were $90.73{\pm}5.87dB(A)$ by SPL, $91.32{\pm}5.50dB(A)$ by Leq and $91.82{\pm}6.06$ by Dose and noise levels of middle unit workplace were $88.31{\pm}5.26dB(A)$ by SPL, $88.41{\pm}4.83dB(A)$ by Leq and $89.69{\pm}5.05$ by Dose. And noise levels of small unit workplace were $94.89{\pm}4.10dB(A)$ by SPL, $85.35{\pm}4.11dB(A)$ by Leq and $86.87{\pm}4.98$ by Dose. The noise level differences of noise measuring methods by unit workplace size were statistically significant by repeated measure ANOV A(P<.05). 5. The noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001). But Interaction between workplace size and noise level measuring methods for noise level was not statistically significant by repeated measure ANOVA. According to the above results, there was a difference of the noise level among the three measuring methods. Therefore we must use the personal noise exposure dose using by noise dose meter, possible, to prvent occupational hearing loss in noisy working environment.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.2
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• pp.37-47
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• 1995

In recent years, it has been variously developed for testing the accuracy of circular motion of NC machine tools, for example Telescoping Ball Bar Method by Bryan, Circular test Method by Knapp and $r^{-{\theta} }$ Method by Tsutsumi etc., but these methods are all 2-dimentional measuring methods on plane. These simple methods of circular motion accuracy test of NC machine tools have been studied by many reserchers as above, but it is not yet settled in the code of measuring methods of motion errors of NC machine tools, because of errors of measuring units and sensors, and also especially the difficulties of centering of measuring units and the spindle of machining center. In this paper, in use of 2 rotary encoders and 1 magnetic type linear scale with resolution of 0.5 .mu. m, it has become possible for measuring of 3 dimentional space motion accuracy.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.2
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• pp.287-296
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• 1995

measuring surface area errors can be brought about with different measuring people. This study aims at eliminating such errors in measurement. With measures by 3 people whose experience varies from person to person, the existing area measuring method using a planimeter and two other methods which use a computer (one using a digitizer and the other using a scanner) have been analyzed and compared. Three methods have not shown a meaningful difference in respect to the value" of area and two methods other than the one using a scanner have shown a meaningful difference among 3 measuring people. Therefore, we propose the method using a scanner by image processing should be a more improved one for area measuring. The arguments for that are as fllows. 1. The operation for measurement is simple and it has a high degree of accuracy with few errors. 2. Because different measuring people cause few errors the operation started by one person can be handed over to anyone else and the operation dosen't require previous skill. 3. Once image file is saved, the operation can be performed on several computers at the same time with seperate part on each computer. 4. Three methods have needed nearly the same length of time, but time for the method using a scanner can be reduced on computers with a higher capacity.th a higher capacity.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.2
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• pp.189-194
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• 2014

Drape property, one of the dynamic properties, is significant element of appearance and silhouette of garment. There are two methods of measuring drape property: objective method and subjective method. The purpose of this study is to search convenient method of measuring drape property which affects the appearance of garment. The method of this study was as below: First, the drape properties of ten various fabrics were measured within both of professional paper ring and visual handy measuring instrument. Second, Pearson's correlation coefficient was analyzed in order to analyze the correlation of two results of the experiments. This study used professional paper ring and visual handy measuring instrument on ten samples. Both of the results from the paper ring and visual handy measuring instrument were very similar in terms of drape property. Significant correlation between results of the professional paper ring and visual handy method indicates the efficiency of the visual handy measuring at school or work environment etc.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.480-483
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• 2007

Recently, many apartment houses were built in nearby road and railway. Road traffic noise level and railroad traffic noise level are important factors on apartment houses inhabitant's acoustic comforts. The measurement methods which noted by Ministry of Construction & Transportation, Ministry of Environment and Korean Industrial Standard are used for measurement of exterior noise at apartment houses. The purpose of this study compare the noise level characteristic by the measuring methods and evaluating methods. The results show that road traffic noise in the daytime appeared by not greatly noise level difference by the measuring method and evaluating methods. But railroad traffic noise appeared by greatly the noise level difference by the equivalent noise level(1hour) and continuous time.

• Journal of the Korea Furniture Society
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• v.15 no.2
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• pp.1-17
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• 2004

This paper attempted to review measuring methods of formaldehyde emission from wood-based panel products. Methods included for the discussion were desiccator methods, extraction method, and various chamber methods. First, the procedures and testing conditions of 24-hour desiccator method was critically reviewed, and an improvement of this method was proposed to meet international standards. Two different small chamber methods ($20\ell$ and $1m^3$ chamber methods) were also compared in terms of their advantages and disadvantages. In addition, the regulation levels of formaldehyde emission of wood-based composite panels were compared for different countries. The selection of a reference method of measuring formaldehyde emission of wood panel products should consider the ease of conducting test and cost required. Results should be exchangeable for different methods.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.428-433
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• 2008

The strength capacity properties of concrete are much influenced by water content which has a significant effect on concrete spalling, especially, in high temperature areas. Therefore, the properties of the material's shall be closely examined first by measuring the water content in each material in order to analyze Concrete Fire Characteristics, and a reliable measuring method shall be presented in order to derive the following influence. The method used to measure the water content within concrete is mainly divided into 4 types; ASTM method, Nuclear Magnetic method, Ultrasonic measurement method, Radio Wave method, etc. It is essential to use a reliable measuring method for each experiment. In this experiment, we measured the water content and humidity of concrete by two methods; Relative/Absolute humidity method using VISALA HM44 measuring equipment which is easily measurable compared with other methods regardless of the shape of the experimental model, and a water content measuring experiment using ASTM C 566. If the aggregates are under the condition that their surface is dry but in saturation, there is no change of water content according to concrete curing methods. However if the aggregates are absolutely dry, the water content is significantly changed according to concrete curing methods.

• Fashion & Textile Research Journal
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• v.19 no.4
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• pp.493-503
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• 2017

This study investigated water vapor permeability of the 73 breathable fabrics for sports-wear according to the materials, finishing methods and fabric structural parameters. The water vapor permeability by KS K 0594 method of PET breathable fabric was superior than that of nylon one, in addition, water vapor permeability of coated or laminated breathable fabrics were higher than those of hot melt or dot laminated fabrics. The water vapor permeability of breathable fabric was dependent on the thickness, weight and density, which was consistent with measuring method. However, water vapor permeability according to materials and finishing method showed different results according to measuring method. The correlation coefficient of WVP of PET breathable fabrics between ISO and KS K measuring methods was -0.83 and the correlation coefficient of WVP of coated breathable fabrics was -0.72 and -0.71 for KS K and ASTM and -0.72 for KS K and ISO in hot melt laminated breathable fabrics. According to regression analysis, WVP of PET breathable fabric by both KSK and ISO measuring methods was highly dependent upon on the density and weight. In addition, WVP of hot melt laminated breathable fabric was highly dependent upon thickness, weight and density. Therefore, relevant measuring method for WVP of breathable fabrics has to be adopted to measure precise breathability.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.245-252
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• 1997

The development of digital camera and advancement of computer processor could simplify the acquisition and the analysis of digial image, and be the real-time processing by the digital photogrammetry. This study is about to enhancement of the image measuring accuracy by the centroid methods. We were able to determine more effective centroid measuring methods and suitable target shape as the development of analysis system and actualize semi-automatic measuring of digital image. And we can supply the weakness of non-metric camera for the geometric internal accuracy of digital image as the correct of Kodak DCS200 camera 8008s lens distortion.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.317-320
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• 2004

The setting time is very important factor affecting the quality of tunnel lining and reinforcement of sloped slope etc. Currently, however, the quality criteria of accelerating admixture to improve it is not established well. In this study, evaluation on setting time measuring methods of a cement accelerating admixture was performed. Six types of measuring methods were checked and a proper measuring method of the admixture were proposed as fellows: (1) the temperature of materials used shall be controlled exactly and (2) to evaluate the properties of it, an admixture usage of $5\%$ (ratio of cement weight) is recommended.