• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.117-123
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• 2000

In this study, total astigmatism and corneal astigmatism were studied 328 eyes of healthy Korean for astigmatism. Total astigmatism was measured by fogging-and-dial technique, and corneal astigmatism was measured with Topcon OM-4 keratometer. Residual astigmatism was determined by a discrepancy between total and corneal astigmatism. The results were as follows: As they aged, there were a statistically significant changes in total and corneal astigmatism but not in residual astigmatism. And the amount of with-the-rule total and corneal astigmatism had a tendency to decrease, but residual astigmatism had no changes. From 30 years, total astigmatism showed a tendency to become against the rule. The average diopteric value was +0.342D in total astigmatism. +0.920D in corneal astigmatism and -0.579D in residual astigmatism.

• Journal of Ginseng Research
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• v.34 no.1
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• pp.23-29
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• 2010

This study examined the biological characteristics of the insect and examined potential cultural controls using peduncle topping methods. Ginseng stem fungus gnat eggs hatched after 5 days; ecdysis lasted 3-4 weeks, and after 5 days pupation, adults emerged. Adults deposited eggs 1-2 days after emerging, and the entire life cycle lasted 32-40 days. The fungus gnats laid eggs $327\times220{\mu}m$ in size on cut planes of stems, but not on intact stem parts that had not been topped or wounded. Analyses of major weather data for the experimental areas and weather data for the past 30 years acquired from the Korea Meteorological Administration revealed that fungus gnat dispersion was prevalent under highly humid conditions and in areas with thick and frequent fogging. Among the topping times examined, fungus gnat damage to ginseng was lowest when topping occurred in late May. Among the five different topping methods evaluated on experimental ginseng farms, the cumulative fungus gnat damage to ginseng was low (0.8%) under partial peduncle topping (removal of peduncle with lateral fruit remaining) and removal of only flower buds (0.6%), with fungus gnat control effects of 82% and 86%, respectively, compared to conventional topping (removal of peduncle about 5 cm above its base). No fungus gnat damage to ginseng was observed under the no-topping treatment. These results suggest that partial topping of peduncles, while letting lateral fruits remain, is a potentially environmentally friendly method of controlling the ginseng stem fungus gnat.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.571-577
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• 2018

Bicycle riders complain of many inconveniences when wearing glasses, sunglasses and masks. The disposable fine dust mask has been developed to resolve such inconveniences of bicycle riders. The scope of research is limited to the fiber which generates one-time static electricity and the shape of the mask due to the characteristic of fine dust mask. The purpose is to design and make the fine dust mask with a simple production process. The new disposable fine dust mask has secured enough space of the mask in front of the mouth by longitudinal folding and minimized stuffiness by maintaining the shape of the folded part to prevent touching the mouth even by heavy breathing. The streamlined sponge is attached at the part of nose support and the area of the cheek has been expanded to be about 2.5cm wider than ordinary masks to improve tight seal at the side. In addition, a new disposable fine dust scarf mask has been developed to block ultraviolet rays for the face and neck while filtering fine dust with the tight fine dust mask.

• Fashion & Textile Research Journal
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• v.25 no.4
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• pp.520-533
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• 2023

The present study developed a test protocol for evaluating the mobility of firefighting chemical and flame personal protective equipment (PPE) for the National 119 Rescue Headquarters in Korea and suggested ergonomic design factors to improve their mobility and performance. Six types of PPE were employed, including three types for flame protective PPE (5 ~ 6 kg excluding the self-contained breathing apparatus), and three types for chemical and flame protective PPE (8 ~ 11 kg). These PPEs are used by the 119 Rescue firefighters. Three male firefighters (34.3 ± 1.2 y in age, 175 ± 8 cm in height, 81 ± 13 kg in body weight) participated in the mobility test and interview. A mobility test protocol consisting of 16 components (nine postures and seven motions including a dexterity test) along with a visibility test were developed based on pre-interviews and literature reviews. The findings indicated that the clothing microclimate humidity on the neck and chest exceeded 85%RH on average for all the six PPE conditions, with the chest area reaching as high as 98%RH. This high humidity caused fogging inside the visor and impaired visibility. The requirements for improving the PPE design in terms of mobility varied depending on whether it was the separated types or all-in-one types, particularly regarding the hood and gloves design. The findings of this study can be applied to improve the design of Level A_PPE for firefighters. The mobility test protocol and visibility test developed in this study can also be applied to other types of Level A impermeable PPE.

• Journal of Biosystems Engineering
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• v.41 no.2
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• pp.98-107
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• 2016

Purpose: The aim of this study was to find an appropriate polymer film, which could reduce the water condensation for pallet-size modified atmosphere packaging (MAP). Methods: Five different types of films were selected from several commercialized films. Prior to the real food storage test, plastic boxes with wetted plastic balls were used to simulate the high humidity conditions of real food storage. The initial MAP condition was 5% oxygen and 95% nitrogen, and the $O_2$ concentration, the relative humidity and water condensation inside the films were checked on a daily basis. The MAP test for tomatoes was conducted by using the most appropriate film from the five films examined in this study. Results: Every film except Mosspack(R) indicated a similar variation in the $O_2$ concentration over the course of time. The relative humidity near the surfaces of all the films except nylon-6 approached saturation conditions over time. For three kinds of films, namely, low-density polyethylene (LDPE) film, anti-fogging oriented polypropylene (AFOPP) film, and Mosspack(R), the inner surfaces of the films were fully covered with dew after a storage period of a day. Conversely, an area of 4.5% was covered with dew in the case of the poly lactic acid (PLA) film, and there was no dew inside the nylon-6 film. The pallet-size MAP test for tomatoes was conducted by using the nylon-6 film and there was no water condensation inside the nylon-6 film over three weeks of storage. Conclusions: During the pallet scale MAP, water condensation could cause severe fungal infection and wetting of the corrugated box. Hence, it was important to minimize water condensation. This study showed that the MAP films with high WVTR such as nylon-6 and PLA could reduce the water condensation inside the pallet scale MAP.

• Food Science and Preservation
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• v.16 no.2
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• pp.147-154
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• 2009

Radish sprout was packaged with different materials. PO and PC are both hard case PET(polyethylenterephthalate) and has 6 holes and no holes, respectively. LO, LM and LH are anti-fogging OPP(oriented polypropylene) film which have different oxygen transmission rates. The oxygen concentration and weight loss rate in PO packaged were higher than any other packages. The soluble solid contents of radish sprouts packaged with PO showed much increased during storage. The pH increased during storage but pH of the samples packaged with high oxygen transmission rate was relatively low. Radish sprouts in LO had lower b value as compared to other samples. The result of ${\Delta}E$ value was generally high during storage period, especially at 7 days storage. The contents of total polyphenolic compounds and free radical scavenging activity of radish sprout packaged with PC and LO were high. Total aerobic bacteria of sprouts in PC and LO was much higher than others. The result of organoleptic qualities showed that the radish sprouts packaged with LM had a good score in terms of overall acceptability until 7 days storage.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.333-339
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• 2015

Purpose: The aim of this study was to evaluate clinical characteristics of subjective accommodative lags determined by fused cross-cylinder (subjective method), and an open-field autorefractor (objective method) under uncorrected and corrected conditions. Methods: Thirty three healthy subjects (26 males and 7 females aged $23.73{\pm}1.35$ years from 22 to 27 years) participated. Four methods were used to determine accommodative lag: (1) a subjective method with the fused cross-cylinder (FCC) under +2.00 D fogging lenses condition, (2) an objective method with the autorefractor under uncorrected condition (3) a corrected method (effective accommodative lag) using equations presented by Gwiazda et al. in objective methods, and (4) a corrected method using equations presented by Mutti et al. in objective methods. Results: The mean accommodative lags were 0.72 D for subjective method, 0.82 D for uncorrected objective method, 0.88 D for corrected method with Gwiazda's equations, and 0.78 D for corrected method with Mutti's equations. There were significant differences between the objective accommodative lags, but no significant differences between the objective and subjective accommodative lags. The effective accommodative lags showed significant correlations between phorias and refractive errors. The effective accommodative lag by Mutti's equations had a high correlation with uncorrected accommodative lags (r=0.99, p<0.001). Conclusions: The objective accommodative lag correlated with phorias and refractive errors. Especially, The effective accommodative lag using Mutti's equations may be considered for clinical availability and qualitative evaluation associated with symptoms.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.309-313
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• 2007

Experiments were conducted to measure rooting and growth of rose cuttings as affected by medium composition and volume. Rosa hybrida 'Red Sandra' and 'Little Marble' were used as test plants. For medium composition test, rockwool, phenolic foam, perlite, vermiculite, peatmoss, coir and a commercial medium (Tosilee medium) were applied in single or mixed forms on the propagation bed with fog (200 sec./5 min.) installed to control the humidification time. 'Red Sandra' and 'Little Marble' cuttings were planted in 16-cell plastic pots and 72-cell plug trays, respectively. For the medium volume test, 72-cell plug trays and 16-cell or 9-cell plastic pots were used. Cuttings with an uniform node with a five-leaflet leaf was soaked in a $500mg{\cdot}L^{-1}$ IBA solution for 30 sec. A fogging system installed on the propagation bed was used for (100 sec./5 min.). Rockwool 1 : peatmoss 1 (v/v) was the most effective on growth and rooting for both cultivars and high volume of Tosilee medium and rockwool were most effective media far both cultivars.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.687-698
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• 2012

This study was conducted to monitor and prevent outbreak of insect pestsin dredged soil dumping area after completion of dredging construction in Masan City. Monitoring was carried out using tent trap, colored sticky trap, and CDC light trap. A total of 217,073 individuals belonging to 23 species from 10 families in 3 orders were collected. In overwintering survey using tent trap, 3 species were collected. 2 species (Leptocera fuscipennis (Haliday) and Ephydra japonica Miyagi) of them were outbreak species. In color sticky trap, more than 96% of total individuals were comprised of five species: Urolepis maritima Walker (43%), E. japonica (19%), Fucellia sp. 1 (13%), Philotelma sp. 1 (10%), and Homalometopus sp. 1 (9%). In CDC light trap, three dominant species were Homalometopus sp. 1 (91%), Glyptotendipes tokunagai Sasa (6%), and L. fuscipennis (1%), representing about 98% of the total. To prevent damage caused by outbreak of insect pests, we carried out ecological control methods such as covering the fresh soil in outbreak area, using light trap, pumping up water and so on, minimizing use of thermal fogging and insect growth regulatorwhen the insect pest population was rapidly increasing.

• Clean Technology
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• v.23 no.2
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• pp.133-139
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• 2017

Bio-based plastics containing the biomass content higher than 25 wt% have been considered as environment-friendly materials due to their effects on the reduction in the $CO_2$ emission and petroleum consumption as well as biodegradability after use. In this study, poly vinyl chloride, plant-derived plasticizers, by adding a biodegradable catalyst was observed a change in the biodegradability and physical properties. To produce the oxidative decomposition transparent bio film, which is broken down in the initial percent elongation and physical properties such as tensile strength, it was to test the safety of the product as a food packaging material. Poly vinyl chloride, primary plasticizer, secondary plasticizer, anti fogging agent, the combined stabilizer were mixed in a high speed mixer, then extruded using an extrusion molding machine, after cooling, winding, to produce a oxidative decomposition transparent bio film and the control film, with a thickness of $12{\mu}m$ through winder role. Mechanical properties tensile strength, elongation, and the maximum load elongation and biodegradation test. Transparent bio film produced by biodegradation catalyst is compared with the control film. Tensile strength and elongation of films were found to be no significant difference. Further, as a result of the biodegradation test for 45 days based on the ASTM D6954-04 method, biodegrability of film is 61.4%.