• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.41-51
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• 2019

With the aging of the population and the slowdown of the job market, elderly workers make up a large portion of the construction workforce. Also, due to the nature of the construction industry, where outdoor work is frequent, the weather has a more sensitive impact on elderly workers than on younger ones. The study aims to analyze the degree of weather risks exposed to elderly workers in the construction industry using the measure of work loss days. To that end, construction accidents that affected 28,514 elderly workers in seven cities from 2012 to 2016 (a total of 12,789 days) were analyzed to calculate work loss days per different weather factors. The results show that the elderly workers were seriously affected when the temperature was between $-12^{\circ}C$ and $-10^{\circ}C$, humidity between 55% and 60%, precipitation between 128mm and 181mm, and wind speed between 5.5m/s and 6.5m/s, with the highest work loss days. The combined effects between the weather factors were also analyzed to identify the conditiosn that leaded to high work loss days of elderly workers. This study contributes to effective safety management and pleasant working environment between weather factors and shedding light on the relationship between weather factors and work loss days of elderly workers.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.1
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• pp.1-8
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• 2021

This study is for the application of functional antibacterial packaging to fresh food. Zeolite/Zinc-polypeptide was coated on PP film at concentrations of 5%, 10%, and 15%, degree of dispersion was verified through FESEM and FT-IR analysis. In addition, the antibacterial and antifungal properties of the films were analyzed according to the control group and the concentration of coating materials. As a result, the degree of dispersion of coating material was irregular but wide, depending on the concentration of Zeolite/Zinc-polypeptide on the surface of PP film. The antibacterial effect against E. coli was over 99.9%, and the growth of R. oryzae was inhibited about 70%. Therefore, it was confirmed that Zeolite/Zinc-polypeptide had antibacterial and antifungal properties against E. coli and R. oryzae even after coated on PP film. In conclusion, Zeolite/Zinc-polypeptide coating film is expected to be effective in preventing corruption and improving the shelf life of fresh food as a functional packaging material. In order to be applied to various fresh foods in the future, storage experiments are additionally required with temperature and humidity conditions according to fresh foods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.1-6
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• 1985

This experiment was designed to determine the effect of light quality on the appearance of photobleaching leaves during the cure of Burley Tobacco. The harvested and browned tobacco leaves were exposed to sunlight in pipe houses covered with 8 kinds of color vinyls (white, red, black, yellow, purple, orange, blue, green), and exposed to ultraviolet rays(20W x 3) and infrared rays (150W x 2) in curing chamber (1.2 x 1.2 x 1.2m). Photobleaching occured more at lower position leaf and after the leaves being browned when the curing was done in sunlight under a transparent vinyl. But photobleaching leaves were 5-6% of total cured leaves in sunlight under all kinds of color vinyl houses. It seems that photobleaching mainly induced by ultrabiolet rays of sunlight, and humidity too influenced. Yellow, orange and purple vinyl were durable and effective as shading material of color vinyls. since white and red vinyl tore easily in two monthes in strong sunlight and under black and blue vinyl houses curing period was longer than others.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1A
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• pp.53-59
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• 2010

Recently, NDTs (Non-Destructive Techniques) using infrared camera are widely studied for detection of damage and void in RC (reinforced concrete) structures and they are also considered as an effective techniques for maintenance of infrastructures. The temperature on concrete surface depends on material and thermal properties such as specific heat, thermal conductivity, and thermal diffusion coefficient. Different porosity on cement mortar due to different mixture proportions can show different heat behavior in cooling stage. The porosity can affect physical and durability properties like strength and chloride diffusion coefficient as well. In this paper, active thermography which uses flash for heat induction is utilized and thermal characteristics on surface are evaluated. Samples of cement mortar with W/C (water to cement ratio) of 0.55 and 0.65 are prepared and physical properties like porosity, compressive strength, and chloride diffusion coefficient are evaluated. Then infrared thermography technique is carried out in a constant room condition (temperature $20{\sim}22^{\circ}C$ and relative humidity 55-60%). The mortar samples with higher porosity shows higher residual temperature at the cooling stage and also shows reduced critical time which shows constant temperature due to back wall effect. Furthermore, simple equation for critical time of back wall effect is suggested with porosity and experimental constants. These characteristics indicate the applicability of infrared thermography as an NDT for quality assessment of cement based composite like concrete. Physical properties and thermal behavior in cement mortar with different porosity are analyzed in discussed in this paper.

• Journal of Korean Society of Forest Science
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• v.41 no.1
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• pp.7-18
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• 1979

Almonds are one of the oldest sources of food and oil for man as used the ice cream, candy, roast, salting, chocolate, breads, backed, cookies, and flavoring ect. So, we wish to plant Almond in our country at the most parts of mountains. In this purpose we must be find out of both root stock of more compatibility and new techniques of grafting was rather simples as compared with the many steps of machinary involved today. This investigation has been carried out to reveral compatibility and practical controls of environment effectives involved in the occurence of each difference combination results in interspecific grafting of Almonds on the root stock of Prunus mandshurica and Prunus persica as materials during the 9 months period from March to November in 1978. With these selected scions were 4 varieties of Almond employing as the Hal1's hardy, Nonpareil, and Thompson grafted in the polyethylene green house with almost identical provision made for effective controls of automatical supplying to heating and mistsprayers as the $22{\sim}25^{\circ}C$ of temperature and 70~90% humidity. Following results have been obtained. Those environmental controls were more effective and practical to grafting unions and success by means veneer-grafting at the green house. 1. Hall's hardy Almond grafted on the root stock of Prunus persica was more compatibility than Prunus mandshurica. 2. The survival percentages as follows of the 95.33% of Hall's hardy/Prunus persica and 92.66% of Hall's hardy/Prunus mandshurica. And those were no significant between root stock of both species. 3. The 3 varieties of sweet Almond grafted on the root stock of P. mandshurica. And those were no significant between root stock of both species. 4. And the survival percentages as fellows. Thompson 92.66%, Nonpareil 90.66% and Kapareil 89.33% those grafted on the root stock of Prunus persica. 5. And then the survival percentage of interspecific grafts on the root Prunus mandshurica as follows of the materials of Thompson 89.66%, Nonpareil 87%, Kapareil 85%. 6. The analysis of variance were no significant among the interactions between 3 varieties Almond and 2 species of root stock plants. 7. And the growth of interspecific grafts of the high 161cm, diameter 12.3mm and length of roots 21.5cm growth as the Hall's hardy Almond grafted on the root stock of Prunus persica. 8. The root stock plants of Prunus mandshurica more effected to 6~8 days early developed leafing of scions and dark green colour than the Prunus persica. 9. The identical provision of automatic systems was more effective to graft unions and grafting process. 10. The veneer-grafting method at the green house was more effective and practical method for the mass production of Almond grafts.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.479-488
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• 1995

Relationships between pine-mushroom(Tricholoma matsutake) yield and important climatic factors for the yield(such as monthly precipitation, relative humidity, temperature, and radiation percentage) were examined to find out limiting factors for pine-mushroom production and to develop a method for overcoming the factors by analyzing the yield and climate data for 17 years collected from 18 main regions of pine-mushroom production. Although there were variations among the production regions, climatic condition of September was the most significant factor for pine-mushroom yield in general, and the degrees of importance of each climatic factors were different among the production regions. Mean minimum temperature of September was positively correlated with pine-mushroom yield($$r^2{\geq_-}0.41$$) at the 1% level, of which were 9 regions such as Youngduck, Uljin, Samchuck, Bongwha arid so on. In these regions, vegetation control was expected to be effective for pine-mushroom production by allowing much sunlight penetration to the pine stand, which may increase soil temperature and keeping the temperature around the fungal colony in soil. Precipitation during September was positively correlated with pine-mushroom yield($$r^2{\geq_-}0.41$$) at Namwon, Moonkyung and Sangju. Thus, irrigation around fungal colony in dry soil during September would be effective for enhancing mushroom yield at the regions. Pine-mushroom yield of 1994 was quite low, similar to that of 1993, due to serious drought. In this period, we could manifest the possibility of enhancing pine-mushroom yield by irrigation for overcoming drought at Moonkyung and Keochang regions.

• Korean journal of applied entomology
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• v.21 no.1 s.50
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• pp.38-48
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• 1982

This study was conducted to investigate the changes in moth occurrence of striped rice barer, Chilo suppressalis (Walker), in relation to climatic factors, rice varieties, and cultural practices. The light trap data from 41 forecasting stations for 14 years from 1966 to 1979 were analyzed by means of the changes in the time and amount of borer occurrence in connection with the introduction of new rice varieties, the accumulated effective day-degree and its variation for completing one generation, and the climatic factors affecting the moth occurrence. The total number of moths caught by light traps in both spring and summer generations were considerably decreased with the wide cultivation of new rice varieties. In fact, the spring moths were remarkably decreased since the new varieties were introduced in 1972. The occurrence ratio of summer moths against the preceeding spring moths was higher in the middle region and middle southern mountainous area than the other regions. Its high ratio of regions was annually expanded from the middle region to the southern region. The $50\%$ emergence dates of both generations were later in the southeastern region than in the middle region. The ecological characteristics were clearly shown between the northern and southern region of Chupungryeong in terms of the occurrence of summer moths, the ratio of occurrence of summer moths to the preceeding spring moths, and $50\%$ emergence dates of the summer moths during the years of $1977\~1979$. The ratio of the summer moth occurrence to the preceeding generation was negatively correlated with the average temperature in lune and July, respectively, and the average precipitation in late June. The ratio of spring moth occurrence over the preceeding generation was positively correlated with the average temperature in September, October, November, and March, respectively, whereas it was negatively correlated with the average precipitation in early September and March, and the average humidity in early May. The effective day-degree for one generation was in the range from 600 to 900 DD at upper threshold $30^{\circ}C$ and lower threshold $10^{\circ}C$.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.25-25
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• 2014

Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.453-457
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• 2016

This study investigates the hatching periods and hatchability of the eggs of Pochazia shantungensis at different collection times from 2011 to 2014, and the effect of temperature on the growth of P. shantungensis nymphs in an area of its outbreak. The hatchability of P. shantungensis eggs varies with their collection time; their hatchability in late November was higher than that in March of the next year, but no difference was observed in their hatching periods. The hatching periods of the eggs were 51.2, 31.3, 24.8, 19.4, 17.1, and 19.4 days at 15, 18, 21, 24, 27, and $30^{\circ}C$, respectively. The hatchability was above 70% at temperatures ranging from 18 to $27^{\circ}C$. The hatching time of the overwintered eggs in the Gurye region in Korea was reduced by 9 days from 2011 to 2014. The hatching rate was relatively higher when the average temperature in the winter season was relatively warmer. The dvelopmental periods of the first to fifth nymphs were 82.8, 58.0, 45.8, and 39.6 days at 18, 21, 24, and $27^{\circ}C$, respectively, at the relative humidity of 40~70%, and a photoperiod off 14 h light:10 h dark. The higher the temperature, the shorter the developmental period. At $30^{\circ}C$, all life stages after the fourth nymph died. Thus, the optimum growth temperature was estimated to be $27^{\circ}C$. For all life stages from the egg to the fourth nymph, the relationship between the temperature and developmental rate was expressed by the linear equation Y = 0.0015 X - 0.014. The lower developmental threshold was $9.3^{\circ}C$ and the effective cumulative temperature was 693.3 degree-days. The lower developmental threshold of approximately $3.8^{\circ}C$ was the lowest at the fourth nymph stage.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.268-295
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• 1997

Sweating is natural phenomenon necessary for the regulation of an individual's body-temperature. The secretion of sweat is mediated by a portion of our vegetative nervous system(the sympathetic nervous system). In some people, this system is working at a very high activity level, far higher than needed to keep a constant temperature. This condition is referred to as hyperhidrosis. Especially excessive sweating of the hands and the feet is palmoplantar hyperhidrosis or volar hyperhidrosis. This is by far the most distressing condition. It was founded that the first important cause of this was emotional factor. The hands are much more exposed in social and prefessional activities than any other part of our body. Many individuals with palmoplantar hyperhidrosis are limited in their choice of proffession, because unable to manipulate materials sensitive to humidity or reluctant to shake hands; some patients arrive to the point to avoid social contact. The occidental medical treatments for palmoplantar hyperhidrosis include application of topical agents(chemical antiperspirants such as aluminum chloride), iontophoresis(treatment with electrical current), or surgery(thoracic sympathectomy). It was reported that the most effective treatment was thoracic sympathectomy. So this study was started to find the easy and effective oriental medical treatments against the occidental medical treatments through the oriental medical literature. The occidental medical idea for palmoplantar hyperhidrosis is only limited in neurologic system, so surgery is the best treatment. But the oriental medical idea for palmoplantar hyperhidrosis is much wider, so the oriental medical causes and treatments for this are able to be veriety. And the oriental medical teatment is freely in treating the patients of palmoplantar hyperhidrosis, because entire idea including pulse, facial color, mental condition, constitution and other symptom exists in the oriental medicine. The results of a bibliographic study of causes and treatments for palmoplantar are as follows; 1. The main causes of pa1moplantar hyperhidrosis are heat in the stomach, damp-heat in the spleen and the stomach, insufficiency of the spleen-qi and the stomach-qi, deficiency of the spleen-yin and the stomach-yin, and the others are the stomach-cold syndrome, stasis of blood and dyspepsia in the stomach, disorder of the liver-qi, deficiency of the heart-yin and the kidney-yin, deficiency of the heart-yang and the kidney-yang, stagnated heat in the liver and the spleen, the lung channel-heat etc. 2. The main methods of medical treatments for palmoplantar hyperhidrosis are clearing out the stomach-heat, eliminating dampness and heat in the spleen and the stomach, invigorating the spleen-qi and the stomach-qi, reinforcing the spleen-yin and the stomach-yin, warming the stomach, relaxing the liver and alleviating of mental depression and tonifying the heart and the kidney etc. 3. The main prescriptions of palmoplantar hyperhidrosis are Taesihotang, Palmultang-kakam, Samyeongbaechusan, Chongbisan, Sasammaekmundongtang, the others are Leejungtang, Hwangkikonjungtang, Seungkitang, Boyumtang, Baekhotang, Chongsimyonjayum, Moyrosan, etc. 4. Local medicine for external use are liquid after boiling alum in water for about 1 or 2 hours, liquid after boiling alum and pueraria root in water and liquid after boiling stragalus root, pueraria root, ledebouriella root and schizonepeta in water, etc. 5. The methods of acupuncture therapy include invigorating Bokyru, Yumkuk and purgating Hapkouk, or invigorating Bokyru, Kihae and purgating Hapkouk, or steadying Hapkouk, Nokung.