• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.104-114
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• 2022

The purpose of using coolant in machining is both to increase a tool life and also to prevent product deformation and thus, stabilize the surface quality by lubricating and cooling the tool and the machining surface. However, a very small amount of cutting mist should be used because chlorine-based extreme pressure additives are used to generate environmental pollutants in the production process and cause occupational diseases of workers. In this study, medical titanium alloy (Ti-6Al-7Nb) was subjected to a processing experiment by selecting factors and levels affecting cutting power in the processing of the Aerosol Dry Lubrication (ADL) method using vegetable oil. The machining shape was a slot to sufficiently reflect the effect of the cutting depth. As for the measurement of cutting force, the trend of cutting characteristics was identified through complete factor analysis. The factors affecting the cutting force of ADL slot processing were identified using the reaction surface analysis method, and the characteristics of the cutting force according to the change in factor level were analyzed. As the cutting speed increased, the cutting force decreased and then increased again. The cutting force continued to increase as the feed speed increased. The increase in the cutting depth increased the cutting force more significantly than the increase in the cutting speed and the feed speed. Through the reaction surface analysis method, the regression equation for predicting cutting force was identified, and the optimal processing conditions were proposed. The cutting force was predicted from the secondary regression equation and compared with the experimental value.

• Stress
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• v.27 no.2
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• pp.199-204
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• 2019

Backgoround: This study aimed to examine the influence of anxiety sensitivity on task performance and physiological stress response, and to assess the effect of depression in this process for the youth population. Methods: We presented participants with an uncontrollable stress situation where they were required to perform mental arithmetic, based on the Montreal Imaging Stress Task (MIST). A total of 29 participants volunteered for this study. They completed the Anxiety Sensitivity Index-Revised and Patient Health Questionnaire-9 to measure their levels of anxiety sensitivity and depression. Two saliva samples, one before and one after the experiment, were collected to assess the change in cortisol levels as an index of physiological stress response. Results: Participants with high anxiety sensitivity showed lower performance on the mental arithmetic tasks and a significant increase in a salivary cortisol level, compared to those with low anxiety sensitivity. Furthermore, cortisol levels showed a remarkable increase where high anxiety sensitivity was coupled with depressed mood. In other hands, the levels of cortisol remained unchanged despite high anxiety sensitivity with low depressed mood. Conclusions: Our results confirm that the interaction between anxiety sensitivity and depression affects participants' task performance and stress response, as measured through behavioral tasks and physiological data with self-report indices. Also, through the physiological data, we examined that those who have a high level of anxiety sensitivity showed maladaptive responses under high stressful situation.

• Current Photovoltaic Research
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• v.12 no.1
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• pp.24-30
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• 2024

To create an environment for growing ginseng sprouts, we developed a solar module that partially transmits and disperses light. A G to G type light transmission and dispersion solar module was developed using glass with a mist pattern applied, and the light dispersion effect of the developed module was confirmed through illuminance measurement. The output of one module is approximately 260 W, and the configuration consists of 48 cells in series in 4 strings. The cultivation system where the developed module will be installed was developed in the form of a container, and three units of 2.6 kW (260 W x 10 EA). The inside of the cultivation system consists of a shading screen, air conditioner, ventilator, plastic pot, etc. to create an environment for cultivating sprout ginseng. As a result of actually planting sprout ginseng, it was confirmed through verification that the plants were grown without any problems.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2842-2849
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• 2024

The amorphous glasses containing PbO, ZnO, MgO, and B₂O₃ have been fabricated using the melt quenching technique. The structural properties have been analysed using the Fourier-transform infrared (FTIR) and Raman spectroscopy. Derivative of Absorption Spectra Fitting (DASF) method have been used to estimate the band gap energy from the UV-Vis absorption data which decreases from 3.02 eV to 2.66 eV with increasing the concentration of the PbO.The four glass samples 0.284 and 0.826 MeV showed unique variations in terms of gamma attenuation ability. LZMB4 glass sample proved to be the mist effective in terms of shielding of gamma radiation as it requires little distance compared to LZMB3, LZMB2 and LZMB1 to attenuate. RPE revealed a raise with increase in the thickness of the material and reduces as the energy raises. TF is superior in LZMB1 compared to LZMB2, LZMB3 and LZMB4, confirming that, LZMB4 will attenuate better. The Z_Eff of the materials was seen falling as the energy increases, confirming that the linear attenuation coefficient of the glass materials decreases when the energy is increased. The results confirmed that, glass material LZMB4 is the best option especially for gamma radiation shielding applications compared to LZMB3, followed by LZMB2, then LZMB1.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.1-9
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• 2011

In order to analyze the change in home ranges depending on the reproductive stage of Pipistrellus abramus, radio-tracking was carried out for a total of 9 individuals, 3 individuals each, by dividing stages into a pregnancy stage, lactation stage, and post-lactation stage from May to August 2009. For radio-telemetry, 0.38g transmitters, R2000 receivers and 3-element Yagi antennas were used. Pipistrellus abramus were captured using a double-stacked mist net and a harp-trap. Analysis of home ranges used a SHP File and ArcGIS 3.3 for GIS, and used a Kernel Home Range Method(KHR) and a Minimum Convex Polygon(MCP) Method for analysis. Home ranges at the pregnancy stage were MCP 100% $13.46{\pm}1.84ha$, MCP 95% $12.28{\pm}2.15ha$, KHR 50% $3.00{\pm}0.71ha$, and home ranges at the lactation stage were MCP 100% $8.13{\pm}0.23ha$, MCP 95% $7.73{\pm}0.63ha$, KHR 50%$1.84{\pm}1.05ha$. Home ranges at the post-lactation stage were MCP 100% $125.58{\pm}97.77ha$, MCP 95% $123.89{\pm}97.73ha$, KHR 50% $28.61{\pm}26.78ha$. As a result, home ranges of pipistrellus abramus showed a significant difference in all of the MCP 100%, MCP 95%, KHR 50% depending on reproductive stages, being largest in the post-lactation stage and smallest in the lactation stage.

• Journal of Preventive Medicine and Public Health
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• v.29 no.4 s.55
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• pp.785-799
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• 1996

We investigated the 1,004 workers who worked in a automobile factory to study the epidemiologic characterists of dermatoses due to cutting oils. Among the workers, 667(66.4%) answered the questionaire. They are belong to 5 departments of the factory-the Engine-Work(258 workers), Gasoline engine Assembly(210), Diesel engine Assembly(96), Power train Work(86), Power train Assembly(17). We measured the oil mist concentration in air of the departments and examined the workers who had dermatologic symptoms. The results were follows; 1) Oil mist concentration ; Of all measured points(52),9 points(17.2%) exeeded $5mg/m^3$- the time-weighed PEL-and one department had a upper confidence limit(95%) higher than $5mg/m^3$. 2) Dermatologists examined 213 workers. 172 of them complained any skin symptoms at that time - itching(32.5%), papule(21.6%), scale(15.7%), vesicle(12.5%) in order. The abnormal skin site found by dermatologist were palm(29.3%), finger & nail(24.6%), forearm(16.2%), back of hand(8.4%) in order. 3) As the result of physical examination, we found that 160 workers had skin diseases. Contact dermatitis was the most common; 69 workers had contact dermatitis alone(43.1%), 11 had contact dermatitis with acne(6.9%), 10 had contact dermatitis with folliculitis(6.3%), 1 had contact dermatitis with acne & folliculitis, and 1 had contact dermatitis with abnormal pigmentation. Others were folliculitis(9 workers, 5.6%), acne(8, 5.0%), folliculitis & acne (2, 1.2%), keratosis(1, 0.6%), abnormal pigmentation (1, 0.6%), and non-specific hand eczema (47, 29.3%). 4) The prevalence of any skin diseases was 34.0 pet 100 in cutting oil users, and 13.3 per 100 in non- users. Especially, the prevalence of contact dermatitis was 23.0 per 100 in cutting oil users and 23.0 per 100 in non-users. 5) We tried patch test(standard serise, oil serise, organic solvents) on 49 patients to differentiate allergic contact dermatitis from irritant contact dermatitis and found 20 were positive. 6) In a multivariate analysis(independant=age, tenure, kinds of cutting oil), the risk of skin diseases was higher in the water-based cutting oil user and both oil user than non-user or neat oil user(odds ratio were 2.16 and 2.78, respectively). And the risk of contact dermatitis was much higher at the same groups(odds ratio were 5.16 and 6.82, respectively).

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.111-116
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• 1979

The experiments were carried out to evaluate the effectiveness of some insecticides in the control of the pine gall midges (Thecodiplosis japonensis Uchida et Inouye) when the low-volume of the insecticides were applied by the mist foliar sprayer. The insecticides, Salithion $(24\%\;Ec)$, Omethoate $(Folimat^{(R)}\;50\%\;Ec)$, Monocrotopos $(Azodrin^{(R)}24\%\;Ec)$, Acephate $(Ortran^{(R)}\;50\%\;Wp)$, Metalkamate $(Bux^{(R)}24\%\;Ec)$. BPMC $(Bassae^{(R)}50\%\;Ec)$ and MIPC $(Mipcin\;50\%\;Wp)$ were tested with 100, 200 and 400 times of water solution on the basis of single application at the six different intervals. Salithion was the most effective for the pressure of the gall formation by the pine gall midges and Omethoate, Monocrotophos and Metalkamate were relativey effective and others no effective. The most reliable concentration of the insecticides was 100 times of water solution, and the feasible timing of insecticide application on the basis of single application would be from May 9 to July 1 with Salithion, June 6 with Metalkamate and June 20 with Omethoate and Monocrotophos. The number of pine needles with the larval injured signs (no larvae in the needles) excluded the gall-formed needles were relatively higher in the treatments of Omethoate, Salithion and Monocrotophos than other insecticides. The treatments of Omethoate, Salithion and Monocrotophos caused the lower larval population in the gall than other insecticides.

• Archives of Plastic Surgery
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• v.45 no.2
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• pp.102-110
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• 2018

Debridement is a crucial component of wound management. Recent technologies such as hydrosurgery (Versajet), ultrasound therapy (the MIST therapy device), or plasma-mediated bipolar radio-frequency ablation therapy (Coblation) seem to represent interesting alternatives for wound debridement. The purpose of this systematic review was to describe, evaluate, and compare these three recently developed methods for the management of chronic wounds. In January 2016, an electronic database search was conducted of MEDLINE, PubMed Central, and Embase for articles concerning these three innovative methods for the management of chronic wounds. A total of 389 references were identified by our search strategy, and 15 articles were included. We extracted data regarding the number and age of patients, indications, operating time, number of procedures, costs, wound healing time, decrease in exudation, perioperative blood loss, bacterial load, and the occurrence of complications. The 15 articles included studies that involved 563 patients who underwent hydrosurgery (7 studies), ultrasound therapy (6 studies), or Coblation (2 studies). Six randomized controlled trials were included that compared the use of a scalpel or curette to hydrosurgery (2 studies) or ultrasound therapy (6 studies). Hydrosurgery, in addition to being a very precise and selective tool, allows significantly faster debridement. Ultrasound therapy provides a significant reduction of exudation, and improves the wound healing time. No comparative study dedicated to Coblation was identified. Despite the obvious clinical interest of the topic, our review of the current literature revealed a lack of prospective randomized studies comparing these devices with each other or with standard techniques, particularly for Coblation and hydrosurgery.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.4
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• pp.112-128
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• 2015

To consider an identity about traditional folk village, this study analyzes color characteristic of traditional folk village by targeting Cuandixia folk village in China. For method of study, color is analyzed by KSCA(Korea Standard Color Analysis) program and images of color are drawn by I.R.I. Based on these, four results are came out. First, color distribution of Cuandixia is appeared in YR, R, Y, GY order. Furthermore, there are no affiliation of BG, and B but a lot of affiliation of YR. Second, the whole is made up of color that is applied to mist gray/low chroma in the value and chroma stakes. Especially, high chroma is extracted by only commercial old house, the rest is made up of middle and low chroma color. Third, dark color is the most by KS Color System and dark reddish gray and medium gray are occupied most part. Fourth, the whole atmosphere of village is static and hard, and the image is researched as gentle. Through the research, It applies extracted color palette for plan and preservation of traditional folk village. As using the color that is reflected in national and local distinct characteristic, preserving the color reflected in history and culture of the village, and applying color planning considered harmony with surrounding environment, it is expected that it can help to direct the color involved traditional and cultural meaning.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.2
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• pp.201-208
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• 2011

Recently, a real-time, pocket-sized aethalometer (microAeth$^{(R)}$ model AE51) has been developed by Magee Scientific Inc. for measuring the concentration of black carbon in the atmosphere. In this study, two aethalometers, models AE-16 and AE-51, which measure the optical absorption of carbon particles at infrared 880 nm, were operated at time interval of 5-min between January 9 and February 10, 2010 at an urban site of Gwangju, to compare the accuracy of black carbon (BC) concentrations reported from the AE-51 model and to investigate reasonable sampling time of filter media in the AE-51. The air samples in the AE-51 and AE-16 models are collected on T60 (Teflon coated glass fiber) filter media (filter spot area: 0.07 $cm^2$) and quartz fiber roll-tape filter (filter spot area: 1.67 $cm^2$), respectively. Real-time measurement results indicate that when the filters were clean, the AE-51 BC was greater than or similar to the AE-16 BC data. However as the filter spots become darker, the AE-16 BC concentrations were higher than the AE-51 BC data and the difference in the BC concentrations from two AE models becomes gradually increased. Relative error in the AE-51 and AE-16 BC concentrations showed significance difference depending on used time of the filter in the AE-51 model, weather pattern, levels of air pollution, etc, ranging from 11.5% (used time of the filter in AE-51: 1,595 min) to 52.5% (used time of the filter in AE-51: 2,085 min). When considering the used time of one filter ticket in the AE-51 model and difference (or relative error %) between AE-16 and AE-51 BC concentrations, it is recommended that the standard sampling time per one filter ticket within the AE-51 model be less than approximately 24 hr (1,440 min) under the normal weather conditions except for severe haze and mist events.