• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.289-293
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• 1997

The effects of plant regulators on direct somatic embryogenesis in liquid culture of Rehmannia glutinosa were investigated and the proper explant for direct somatic embryo formation was studied. Direct somatic embryos were induced from leaf segments culture in the MS liquid medium containing 0.5 mg/l of both IAA and NAA, while IBA of 1.0 mg/l was required for the same effect. Many somatic embryos were directly formed at the concentration of 2.0 mg/l cytokinin such as BA, kinetin and zeatin, but somatic embryogenesis was relatively poor at above or below this level. Relatively more somatic embryos were induced in the combination of 1.0mg/l IAA and 2.0mg/l zeatin. Formation of somatic embryos begun after 6 weeks on stem segments, while 7 weeks both on petiole and leaf. However, overall production of somatic embryos after 8 weeks was higher in leaf segment than that of stem segment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.6 no.1
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• pp.1-8
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• 1977

The sample persimmons were obtained from the of Yung-am Kun, Korea on October 24, and November 9, 1973. These persimmons were kept at room temperature overnight, then packed and stored on the following day at $0^{\circ}C$ and $85{\sim}100%$ humidity. Seven experimental items were studied : 1. control, 2. packing with excelsior in wooden boxes, 3. packing with rice hull in wooden boxes, 4. packing in bags of 0.03 mm polyethylene membrane, 5. packing in bags of 0.06 mm polyethylene membrane, 6. packing in bags of 0.08 mm polyethylene membrane, 7. packing in sealed desiccators. The dimension of polyethylene bags were $14{\times}28cm$ and three persimmons were packing in each bag. The results are as follows: 1. The persimmons both in polyethylene bags and in desiccators lost only 1 % or less of weight, while in control (1) packing with excelsior (2) or with rice hull (3) the loss was 6-7 % in weight after $2{\sim}3$ months. The persimmons became visibly shriveled and spongy-like in it's texture when it lost 5 % of weight. 2. Carbon dioxide content within the polyethylene bags and desiccators rapidly increased during the early storage period, and reached 5 % (in 0.03 mm polyethylene bags) to 50 % or more (in desiccator) after 1 month. In the polyethylene bags of 0.08 mm and desiccator, the carbon dioxide accumulated to a dangerous level and the persimmon showed physiological damage in a longer storage period. 3. The advance of after-ripening and deterioration of persimmon sealed in the polyethylene bags was slower than that in open bags when moved out to room temperature from the chilling and the polyethylene bags of 0.06 mm retarded the after-ripening most effectively. 4. On the basis of these results, a temperature of $0^{\circ}C$, relative humidity of almost $85{\sim}100%$ and combinations of 5 % oxygen and $5{\sim}8%$ carbon dioxide seem to be the optimum condition for the storage of persimmon (Teabong-Si). The most successful method of storing was to pack them in polyethylene bags of 0.06 mm and then to store them at $0^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.295-304
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• 2015

To develop a technique for efficient management of fertility for cucumber in greenhouse, a quick test method to quantify nitrate ($NO_3{^-}$) content in soil solution and leaf petiole juice using a simple instrument that are easy to use for farmers was investigated. N fertilizer (urea) was applied at 0, 50, 100 and 200% levels of the recommended application rate from 30 days after transplanting to harvest by soil fertigation treatments. Stable results were obtained from analysis of nitrate ($NO_3{^-}$) using top $10^{th}$ or $11^{th}$ leaf petioles collected between 10 to 11 am in the morning. Under the semiforcing culture, $NO_3{^-}$ content of leaf petiole juice was highest at 60 days after transplanting (DAT) at all fertigation treatments. Appropriate $NO_3{^-}$content of leaf petiole juice was $2,418{\pm}78{\sim}2,668{\pm}118$ at 45 DAT, $3,032{\pm}90{\sim}3,332{\pm}63$ at 60 DAT, $2,709{\pm}50{\sim}3,158{\pm}155$ at 75 DAT, $2,535{\pm}49{\sim}2,907{\pm}83$ at 90 DAT, and $2,242{\pm}48mg\;L^{-1}$ at 105 DAT. In addition, appropriate $NO_3{^-}$ content of soil solution was $167{\pm}9{\sim}212{\pm}15$ at 45 DAT, $83{\pm}10{\sim}112{\pm}12$ at 60 DAT, $49{\pm}3{\sim}92{\pm}6$ at 75 DAT, $71{\pm}9{\sim}103{\pm}9$ at 90 DAT, and $73{\pm}9mg\;L^{-1}$ at 105 DAT. The cucumber yield at 100% N level of fertigation was $7,770kg\;10a^{-1}$ and no difference in yield was found at 200% N level of fertigation. However, there was 12% decrease in yield at 50% N fertigation and, 17% decrease at 0% N fertigation. Under retarding culture, $NO_3{^-}$ concentration of leaf petiole juice was highest at 55 days after transplanting (DAT) at all fertigation treatments. Appropriate $NO_3{^-}$ content of leaf petiole juice was $2,464{\pm}102{\sim}2,651{\pm}33$ at 45 DAT, $3,025{\pm}71{\sim}3,314{\pm}84$ at 55 DAT and $2,488{\pm}92mg\;L^{-1}$ at 65 DAT, respectively. Appropriate $NO_3{^-}$ content of soil solution was $111{\pm}10{\sim}155{\pm}14$ at 45 DAT, $93{\pm}7{\sim}147{\pm}14$ at 55 DAT, $67{\pm}4mg\;L^{-1}$at 65 DAT, respectively. The cucumber yield at 50% N fertigation was not different from $1,697kg\;10a^{-1}$ of 100% N fertigation level and even with that of the 200% N fertigation. However, there was 21% decrease in yield at 0% N fertigation.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.13-33
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• 1999

The aim of this study was to investigate fatigue scores, physical complaints, farmer's syndrome and to find out its risk factors among farmers. The questionnaire survey was conducted to 177 vinyl house workers and 213 farmers who lived in Chongyang gun of Chungnam province from February 24 to March 15, 1998. The obtained main results were followings; 1. The fatigue scores were not significantly different between vinyl house workers and farmers. The fatigue scores were higher in female group, lower education group, shorter sleep hours group(under 8 hours), nonsmoker, nondrinker group than otherwise groups. There was not statistically significant difference between the mean fatigue scores and age, eating habit and body mass index. Duration of farming years in vinyl house and farming area and number of farming workers in farmers family showed a slight relationship with the fatigue score. 2. Health scores were not different between vinyl house workers and farmers. The health states was poorer in female group, lower education group, shorter sleep hours group(under 8 hours), nonsmoker group, and nondrinker group than otherwise groups by health scores. Health scores were not related with age, eating habit and body mass index. 3. The proportion of farmer's syndrome was 49.1% in vinyl house workers and 52.1% in farmers. That was higher in female than in male and the higher proportion was found in the lower education group of vinyl house workers and farmers. The proportion of farmer's syndrome was higher in the group of smoker, alcohol drinkers and over or under weight in vinyl house workers, but did not differ in those of farmers. 4. By multiple logistic regression, sex and sleep hours were risk factors affecting to farmer's syndrome. Odds ration for female group was 2.53 (reference group was male) and that for over 8 sleep hours group was 0.74 (reference group was under 8 sleep hours group). 5. The chief complaints by CMI were "I am difficult to work due to aching the back and the limbs", "I feel prickle pain in the limbs", "I sometimes have a twinge in the limbs", "I am not quite well as having a pain in the limbs", "I feel weaker grasping power than before" in both of vinyl house workers and farmers. Vinyl house workers more frequently pointed out skin darkening, skin disease and hemorrhoids than farmers. 6. According to correspondence analysis, skin disease of vinyl house workers was related to vinyl house farmers and digestive and general symptom was associated with male and endocrinological and muscular symptom was associated with female in vinyl house workers. And it revealed that farmer's syndrome was highly related with female and farmers relatively. By the above results, the fatigue scores, perceive health and farmer's syndrome did not much differ in two groups, but aged female farmers should be considered as female farmers represented higher fatigue score, farmers syndrome and poorer perceive health than male farmers in addition to farmer's syndrome was increased with ageing process. Also feeble but distinguished symptoms which might be due to working environment were observed especially in vinyl house workers and that should be considered and investigated continuously.

• Journal of the Korean Electrochemical Society
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• v.23 no.2
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• pp.25-38
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• 2020

Photoelectrochemical water splitting has been considered as the most promising technology for generating hydrogen energy. Transition metal dichalcogenide (TMD) compounds have currently attracted tremendous attention due to their outstanding ability towards the catalytic water-splitting hydrogen evolution reaction (HER). Herein, we report the synthesis method of various transition metal dichalcogenide including MoS₂, MoSe₂, WS₂, and WSe₂ nanosheets as excellent catalysts for solar-driven photoelectrochemical (PEC) hydrogen evolution. Photocathodes were fabricated by growing the nanosheets directly onto Si nanowire (NW) arrays, with a thickness of 20 nm. The metal ion layers were formed by soaking the metal chloride ethanol solution and subsequent sulfurization or selenization produced the transition metal chalcogenide. They all exhibit excellent PEC performance in 0.5 M H₂SO₄; the photocurrent reaches to 20 mA cm^-2 (at 0 V vs. RHE) and the onset potential is 0.2 V under AM1.5 condition. The quantum efficiency of hydrogen generation is avg. 90%. The stability of MoS₂ and MoSe₂ is 90% for 3h, which is higher than that (80%) of WS₂ and WSe₂. Detailed structure analysis using X-ray photoelectron spectroscopy for before/after HER reveals that the Si-WS₂ and Si-WSe₂ experience more oxidation of Si NWs than Si-MoS₂ and Si-MoSe₂. This can be explained by the less protection of Si NW surface by their flake shape morphology. The high catalytic activity of TMDs should be the main cause of this enhanced PEC performance, promising efficient water-splitting Si-based PEC cells.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.72-84
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• 1993

This study was carried out to understand the varietal variation in physicochemical properties of rice grain and those environmental changes by different transplanting time, and to elucidate the interrelationships among the factors related with eating quality of cooked rice. Fifty three rice samples, among which fifty samples were harvested at ordinary or late transplanted plots of the Crop Experiment Station in Suwon and three samples were harvested orpurchased from Niigata prefecture in Japan, were tested for various physicochemical components of rice grain and some physical factors of cooked rice. All of twenty seven rice cultivars tested were the recent-bred Korean japonica rice showing the wide range of maturity from early to medium-late heading and considerable difference in palatability of cooked rice. Amylose content, taste value by Nireco palatability tester (TVN), iodine blue color of cooking extracts(IB), and the ratio of IB /extracted solid amounts (ES) increased significantly by late transplanting, while viscosity (VN) and Mg / K. N value by Nireco tester, hot-water absorption of milled rice (HA), loss tangent of cooked rice by Rheolograph-Micro(LT), and most viscogram characteristics except setback viscosity (C-P) decreased drastically by late transplanting as compared with ordinary transplanting. Most of physicochemical properties of milled rice revealed narrower varietal variation in lately transplanted plot than in ordinary transplanted one. Protein content (PRO), volume expansion rate of cooked rice(VE), C-P and all physical factors of cooked rice by Rheolograph-Micro showed almost negligible seasonal variation, while amylose content (AM), VN, HA, IB/ES, peak viscosity(P), hot viscosity(H) and breakdown(P-H) viscosity exhibited considerably large seasonal variation. The early-headed varieties revealed lower amylose content and smaller seasonal variation of IB/ES compared with medium or medium-late headed rice varieties. AM was closely associatied with IB and IB / ES and VN was highly correlated with Mg/K. N and TVN in both ordinary and late transplanted plots. VN also was highly negatively correlated with cooking characteristics and highly positively correlated with viscogram properties in ordinary culture. PRO was closely connected with moisture content of milled rice and L T in ordinary transplanted plot. IB, which was closely connected with ES, was also singificantly associated LT, P and P-H in ordinary seasonal culture. IB/ES was highly negatively correlated with P, P-Hand P-H / C-P in ordinary culture but with LT and dynamic viscosity of cooked rice in late seasonal culture. The thirty rice cultivars were largely classified into two varietal groups by cluster analysis with physicochemical properties related with eating quality of cooked rice. Korean and Japanese high-quality rice cultivars were separately distributed in two respective varietal group.

• Sijohaknonchong
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• v.21
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• pp.77-110
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• 2004

This study is an exploration of a Korean-American writer, Hong-Eun's Mong-yu siga. Hong-Eun immigrated to the United States during the colonial rule of the Japanese government. He was a publisher of The New Korea Times, and contributed various literary works to it. The purpose of this study is to analyze his two Mong-yu sigas published in 1935 and 1947 and elucidate their meanings. Using dream as a primary motif, the intention of Mong-yu mode is to achieve desire which is impossible to reach in reality. While his staying in the United States, Hong-Eun could not return his home country for two reasons, that is, political and financial ones. To return Korea desperately, he wrote sigas by adopting Mong-yu mode. His first attempt was reflected as eight pieces of consecutive poetries titled This Mountain In My Dream, I am Home. This Mountain was published on the 25th of April, 1935 and In My Dream, I am Home was contributed from May the 9th of 1935 to July the fourth of the same year. These works were published in the The New Korea Times' poetry column under the pen name of Donghae-soboo , Representing gasa of the enlightenment era, this poetry depicts historical identity of Chosun dynasty, especially focusing on before and after the 1900s. As a result of it, the poetry sketches the ideology of the Middle Ages. His second attempt was A Country and Hometown written as a form of prelude on the 25th of September, 1947. In addition, A Country in My Dream was published as a form of six pieces of consecutive poetry from October the second to November the sixth of 1947. He chose sijo as a major form of poetry, and the image of the poetry seemed to be the continuation of his first attempt. Confronting the reality of the his own country which is divided, the writer expresses his antagonism toward America and Russia. Although he could eventually return his country later, he rationalized himself by saying that his it is not the ideal place to go. Mong-yu mode is a traditional poetic technique which the intellectuals of the Middle Age used to use as one pattern of allegory. In addition to this, in the period of the enlightenment of Korea, Mong-yu was used to avoid the Japanese censorship and experiment on the diverse ways of writing. In terms of literary history, the significance of Hong-Eun's creation of Mong-yu sigas is that Hong-Eun shares the same intention with Korean intellectuals of the enlightenment period.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.2 no.1
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• pp.113-160
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• 1996

Cancer is one of the most important cause of death. So recently, investigation of cancer progress prosperously all over the world. Cancer in the present medicine correspond to You-Am, Sin-Am, Young-Soon, Sel-Gyun, Sil-Young, Young-Lyoo, Seg-Je, Seg-Young, Seg-Ha, Jerk-Chui(積聚), Jing-Ha, Oel-Gyek, Ban-Oui, Bi-Gi, Bok-Lyang, Jang-Dan, Hyen-Bek in the oriental medicine. Among these, generally Jerk-Chui(積聚) is expressed to cancer. So to develop of new drugs of cancer in the present medicine, bibliographic investigation of mass-prescriptions was studied in the oriental medicine-books. According to the bibliographic study of Jerk-Chui-prescriptions, the results run as follows. 1. According to the analyses of three hundred sixty eight Jerk-Chui-prescriptions in the twenty-seven kinds of literature, the frequency number of the used drugs were Pericarpium Citri Nobilis Viride 140 times, Pericarpium Citri Reticulatae 135 times, Rhizoma Scirpi 124 times, Radix Aucklandie 115 times, Rhizoma Zedoariae 114 times, Cortex Magnoliae Officinalis 111 times, Radix Glycyrrhizae 106 times, Rhizoma Zingiberis 100 times, Rhizoma Coptidis 94 times, Radix Ginseng 93 times, Poria 86 times, Rhizoma Pinelliae 85 times, Semen Arecae 83 times, Rhizoma Cyperi 82 times, Radix Angelicae Sinensis 80 times, Rhizoma Atractylodis 74 times, Massa Fermentata Medisinalis 67 times, Radix Et Rhizoma Rhei 66 times, Fructus Aurantii 62 times, Fructus Hordei Genninatus 55 times, Conex Cinnamomi 54 times, Fructus Evodiae 51 times, Fructus Aurantii Immaturus 49 times, Fructus Crataegi 49 times, Rhizoma Cnidii 46 times, Radix Platycodi 44 times, Semen Tiglii 44 times, Radix Aconiti 43 times, Fructus Amoni 38 times, Semen Raphani 37 times, Radix Aconiti Praeparata 36 times, Radix Scutellariae 35 times, Pericarpium Zanthoxyli 35 times, Rhizoma Corydalis 33 times, Rhizoma Acori Graminei 31 times, Carapax Amydae 31 times, Fructus Foeniculi 31 times, Semen Persicae 30 times, Radix Bupleuri 30 times. 2. The frequency number of the most imponant used drugs in the Jerk-Chui-prescriptions were Rhizoma Coplidis 41 times, Rhizoma Scirpi 35 times, Radix Et Rhizoma Rhei 31 times, Pericarpium Citri Reticuiatae 30 times, Rhizoma Zedoariae 27 times, Rhizoma Cyperi 22 times, Cortex Magnoliae Officinalis 22 times, Rhizoma Atraclylodis 22 times, Pericarpium Citri Nobilis Viride 21 times, Rhizoma Pinelliae 20 times, Semen Arecae 20 times, Fructus Crataegi 18 times, Rhizoma Zingiberis 17 times, Carapax Amydae 16 times, Semen Pharbitidis 13 times, Poria 12 times, Radix Angelicae Sinensis 10 times, Semen Persicae 10 times, Fructus Evodiae 10 times, Radix Aeoniti 10 times, Radix Glycyrrhizae 9 times, Massa Fennenlata Medisinalis 9 times, Fructus Aurantii 9 times, Fructus Hordei Genninatus 8 times, Radix Aueklandie 8 times, Rhizoma Atractylodis 8 times, Radix Bupleuri 8 times, Radix Ginseng 7 times, Semen Raphani 7 times, Radix Astragali 7 times, Cortex Cinnamomi 6 times, Fructus Aurantii Immaturus 6 times, Rhizoma Cnidii 6 times, Radix Aconiti Praeparata 5 times, Fructus Foeniculi 5 times, Lacca Sinica Exsiccata 5 times, Radix Aconiti 5 times, Rhizoma Zingiberis 5 times. 3. The clinical-botanic classifications of the used drugs in the Jerk-Chui-prescriptions were regulating the flow of Qi drugs, warm-heating drugs, promoting blood circulation drugs, killing mass drugs, resolving drugs, purgative drugs, Qi and blood tonics drugs, heat clearing drugs, removing dampness by promoting diures is drugs, phlegm eliminating drugs, allaying pain drugs. 4. According to the nature and taste in the drugs, warm and heating recipes were used most, heatclearing recipes were used a few times assistantly. 5. The Jerk-Chui-prescription used frequently was Bun-Don-Tang, which was used 13 times ; Bok-Oyang-Hoan 12 times, Bi-Gi-Hoan(肥氣丸) 12 times, Sik-Boon-Hoan 12 times, A-Uie-Hoan 12 times, Bi-Gi-Hoan 12 times, Dai-Cil-Gi-Tang 8 times, San-Cuie-Tang 8 times, Guye-Gyen-Tang 6 times, On-Baig-Won 5 times, So-Jek-Jeng-Ouen-San 5 times, Jin-In-Hoa-Cel-Tang 5 times, Byel-Gab-San 5 times, Sng-Hong-Hoan 5 times, Ji-Sil-San 4 times, So-A-Oie-Hoan 4 times, Hyang-Rng-Hoan 4 times.

• Clinical and Experimental Pediatrics
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• v.53 no.1
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• pp.72-79
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• 2010

Purpose: Left ventricular (LV) hypertrophy and impaired diastolic function may occur early in systemic hypertension. Diastolic dysfunction is associated with increased cardiovascular risk. Tissue Doppler imaging (TDI)-derived tissue velocity and strain rate are new parameters for assessing diastolic dysfunction. The aim of this study is to determine whether TDI and strain rate imaging (SRI) would improve the ability to recognize early impaired diastolic and systolic functions compared with conventional echocardiography in hypertensive adolescents. Methods: We included 38 hypertensive patients with systolic blood pressure above 140 mmHg or diastolic blood pressure above 90 mmHg. Ejection fraction and myocardial performance index (MPI) were estimated by conventional echocardiography. Peak systolic myocardial velocity, early diastolic myocardial velocity (Em), and peak late diastolic myocardial velocity (Am) were obtained by using TDI and SRI. Results: In the hypertensive group, interventricular septal thickness was significantly increased on M-mode echocardiography. Em/Am was significantly decreased at the mitral valve annulus. Among hypertensive subjects, the E strain rate at basal, mid, and apex was significantly decreased. Systolic strain was significantly decreased at the septum in the hypertensive group. Conclusion: Strain rate might be a useful new parameter for the quantification of both regional and global LV functions and could be used in long-term follow up in hypertensive patients. Early identification by SRI of subjects at risk for hypertensive and ventricular dysfunction may help to stratify risk and guide therapy. Further studies, including serial assessment of LV structure and function in a larger number of adolescents with hypertension, is necessary.

• Journal of Bio-Environment Control
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• v.28 no.2
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• pp.126-133
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• 2019

In recent years, the deterioration of fruit quality caused by poor coloration and sunburn disorder has become serious problems in apple market, which is a result of the increase of surface temperature due to the abnormal temperature increase during summer season. This study was conducted to investigate the effect of wind net shading and fine water spray using sprinkler on fruit coloration, sunburn damage and overall fruit quality of 'Fuji' and 'Hongro' apples. Fifteen sprinklers (7L/hr) were installed at the orchard of the Chungcheongnam-do Agricultural Research and Extension Services, located in Sinam-myeon Chungcheongnam-do Korea, at a height of 3m above the apple tree of $1.5m{\times}3.5m$ north-south direction. Fine water spraying treatment was divided into day time spray (10:00 am to 6:00 pm) and all day spray (10:00 am to 10:00 pm) from early July to 10 days before harvest in 2017 and 2018 season, respectively. Temperature of the surface of apple fruit, characteristic of fruit, and degree of sunburn damage were investigated. In 'Fuji', the fruit surface temperature checked at 2 pm on August 10 was decreased considerably in the day time spray ($35.6^{\circ}C$) and wind net ($39.0^{\circ}C$) when compared with the untreated control ($44.4^{\circ}C$). Similarly, the fruit surface temperature also decreased considerably in the all day spray ($35.1^{\circ}C$) and wind net ($36.9^{\circ}C$) treatments when compared with the untreated control ($46.5^{\circ}C$) in 'Hongro' apples. The incidence of sunburn disorder was significantly decreased with day time spray (5.0%), all day spray (5.8%) and wind net (7.0%) when compared with untreated control (23.4%) in 'Fuji' apples. As a results, the treatment of fine water spray and wind net consequently showed 26% and 34% increase of redness ($a^*$) value in the skin color difference, respectively, in 'Fuji' apples.