• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.13-22
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• 2008

The initiation and growth processes of cyclic ice body in porous systems are affected by the thermo-physical and mass transport properties, as well as gradients of temperature and chemical potentials. Furthermore, the diffusivity of deicing chemicals shows significantly higher value under cyclic freeze-thaw conditions. Consequently, the disintegration of concrete structures is aggravated at marine environments, higher altitudes, and northern areas. However, the properties of cyclic freeze-thaw with crack growth and the deterioration by the accumulated damages are hard to identify in tests. In order to predict the accumulated damages by cyclic freeze-thaw, a regression analysis by the response surface method (RSM) is used. The important parameters for cyclic freeze-thawdeterioration of concrete structures, such as water to cement ratio, entrained air pores, and the number of cycles of freezing and thawing, are used to compose the limit state function. The regression equation fitted to the important deterioration criteria, such as accumulated plastic deformation, relative dynamic modulus, or equivalent plastic deformations, were used as the probabilistic evaluations of performance for the degraded structural resistance. The predicted results of relative dynamic modulus and residual strains after 300 cycles of freeze-thaw show very good agreements with the experimental results. The RSM result can be used to predict the probability of occurrence for designer specified critical values. Therefore, it is possible to evaluate the life cycle management of concrete structures considering the accumulated damages due to the cyclic freeze-thaw using the proposed prediction method.

• Korean Journal of Environment and Ecology
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• v.21 no.4
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• pp.311-317
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• 2007

This study was conducted to determine the geographical distribution and habitat for Rana catesbeiana and Trachemys scripta elegans in order to obtain the current basic data on biota needed for establishing a database on non-indigenous species(NIS) in Jeju-do and to develop management plans applicable to Jeju, starting from March 2005 until May 2006. As a result of an inspection, it was found that the habitat for R. catesbeiana in Jeju includes Hankyeong-myeon, Daejeong-eup, and Ahndeok-myeon. These areas are all located on the western side of Jeju-do, and considered to have favorable conditions for R. catesbeiana to inhabit. Thus, it is unlikely that the population of R. catesbeiana will possibly decrease; what's worse, there exists even a risk that it could not only expand to other regions but also do damage to the population of native insecta, fishes, amphibians and reptiles, so this terrible species ought to be exterminated. More than 92 individuals of T. scripta elegans species were found to inhabit in 15 ponds around Jeju Island. T. scripta elegans. as the topmost predator, could destruct the pond ecosystem, and also cause a problem of water pollution due to its excrement. Counter-measures against T. scripta elegans could include publicity activities encouraging self-control of the release of captive T. scripta elegans, extermination plans using its ecological habits, and sign-posting publicizing its hazard to healthy ecosystem at the areas with high population density of T. scripta elegans or at its habitats with high foot traffic, together with the continuous management of NIS(none-indigenous species).

• Journal of Sasang Constitutional Medicine
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• v.18 no.1
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• pp.30-40
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• 2006

1. Objectives The present study purposed to examine the contents and the principles of music therapy according to Oriental medicine theories in order to prove that music therapy is not a new research area but its principle is found in the long tradition of Oriental medicine. 2. Methods We investigate the possibility of music therapy based on Oriental medicine theories and examine the meanings of music therapy from the viewpoint of Oriental medicine. 3. Conclusions and discussions (1) The principles of music therapy are the principle of homogeneity, catharsis and balance. (2) When one’s mind changes, there are naturally occurred sounds, which are called Oseong (五聲: the oriental five voices exhalation, laughing, singing, wailing and groaning), and the notes defined by arranging the Oseong according to the principle of Ohaeng (五行: the oriental five phases wood, fire, earth, metal, water) are Oheum (五音: the oriental five musical notes Gakeum, Chieum, Gungeum, Sangeum and Wooeum.). If Eum (musical notes) is classified into Ohaeng, it can be divided into Gakeum, Chieum, Gungeum, Sangeum and Wooeum. (3) Change of Sinji (神志: consciousness) induces change of Gigi (氣機: function of Gi), which can change the character of voices. Oseong controls the functions of Ojang (五臟: the oriental five viscera) by ruling one’s Jeongji (情志: emotion). It can reduce the damage of the viscera caused by excessive vent of emotion resulted from unconscious expression of Oseong - Hoseong (呼聲: exhalation), Soseong (笑聲: laughing), Gaseong (歌聲: singing), Gokseong (哭聲: wailing) and Sinseong (呻聲: groaning). (4) Yijeongseungjeong (以情勝情: Control emotion with emotion) therapies, which suppresses an emotion by stimulating another, include Noseungsabeop (怒勝思法: Control anxiety with anger), Heeseungbibeop (喜勝悲法: Control sorrow with joyfulness), (思勝恐法: Control fear with anxiety), Biseungnobeop (悲勝愁法: Control anger with sorrow) and Gongseungheebeop (恐勝喜法: Control joyfulness with fear). (5) Seongeum (聲音: voices and musical notes) can be applied to a stimulation method that not only harmonizes the rhythm of living organs but also controls the occurrence of diseases caused by mutual Pyeonseongpyeonsoi (偏盛偏衰: relative preponderance and weakness) through direct induction of the strength and weakness of Gi function of the oriental five viscera in a human body according to the individual character. Sounds preferred by the patient, the material of an instrument selected by the patient, the character of rhythm and music expressed by the patient and the sound or voice uttered frequently by the patient can be considered in diagnosis and treatments for the patient’s body and mind.

• Journal of Korean Society of Forest Science
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• v.46 no.1
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• pp.1-9
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• 1980

This study was carried out to examine the substitution possibility into fiber pot instead of Jiffy pot for the good transplanting. Fiber pot was made of fiber, wood waste particle, and bark powder (10% of the particle weight) and also latex was added into the furnish as a binder. The pots were sprayed with just enough urea solution to prevent nitrogen deficiency of pot media coming from the breakdown of wood fiber in the pot wan during the plant growing. The utility of fiber pot was compared with that of Jiffy pot in the service test of two tree species under a green-house condition. The results obtained can be summarized as follows ; 1. Fiber pot made of 30% wood fiber+70% particle including 10% of bark powder, and 3%-latex has shown a good results like that of Jiffy pot in the sp. gr., tear factor and burst factor. For water absorption, fiber pot made of 50% fiber+50% particle, and 3%-latex got the best result. In the consideration of the above physical and mechanical properties of the fiber pot for good root penetration through the pot wall and facile handling, fiber pot made of 30% fiber+70% particle, and 3%-latex may be seemed to be good. 2. There were no harms in sapling growth in fiber pot as well as in Jiffy pot. The root penetration ability through the fiber pot was slightly inferior to that of Jiffy pot, and yet the pot damage through transportation seemed to be slighter in fiber pot than in Jiffy pot.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.63-71
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• 2014

Objectives : Lonicerae japonicae Flos(LJF) has been reported to exhibit anti-oxidant, anti-inflammatory, anti-viral, anti-rheumatoid properties. However, it is still largely unknown whether LJF inhibits the ultraviolet(UV)B-induced oxidative damage in human HaCaT keratinocytes. Therefore in this paper, we investigated the anti-oxidative capacity and protective effect of LJF against UVB-induced oxidative demage in human HaCaT keratinocytes. Methods : To evaluate the anti-oxidative activity of LJF extracts, we measured total phenolic contents, total flavonoid contents, antioxidant capacity, and superoxide scavenging activity. To give an oxidative stress to HaCaT cells, UVB was irradiated with $200mJ/cm^2$ to HaCaT cells. To detect the protective effect of LJF against UVB, we measured cell viability, DNA fragmentation and reactive oxygen species (ROS) production. In addition, we performed high-performance liquid chromatography (HPLC) analysis to find a major component of LJF. Results : LJF contained phenolic and flavonoid contents, and showed the anti-oxidant and superoxide scavenging activity. The UVB-induced oxidative conditions led to the cell death, DNA fragmentation and reactive oxygen species (ROS) production. However, pretreatment with LJF reduced oxidative conditions, including inhibition of cell death, DNA fragmentation and ROS production. In addition, we found out chlorogenic acid as major component of LJF. Conclusions : These results could suggest that LJF contained anti-oxidative contents and exhibited protective effects against UVB on human HaCaT keratinocytes. And the effective compound of LJF which could show protective activities against UVB is chlorogenic acid. Thus, LJF and chlorogenic acid would be useful for the development of drug or cosmetics treating skin troubles.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.177-186
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• 2005

The latest concrete structure has showed that the deterioration of durability has been increased by the damage from salt, carbonization, freezing & thawing and the others. Therefore, the measures for the concrete which has deteriorated durability have been taken. Among them, it has been often used that surface treatment which cuts off the deterioration factors of durability by protecting the surface of concrete. However, troubles such as fracture and rupture in the repair layer have been reported as time goes by due to the difference between the organic repair material like epoxy and concrete properties. Researchers have been developing the repair material which can cut off the deterioration factors of durability such as $CO_2$ gas, chloride ion and water by making the formation of concrete elaborate through the reaction with calcium ion when the surface improving agent is coated on the concrete. The main ingredient of that is inorganic substance which is the same as the concrete property. This study was evaluated the surface improving agent for permeability, watertightness, air-permeability, chemical resistance and elution resistance. As a result, it has been reported that the surface improving agent improves watertightness and air-permeability by penetration more than 10mm within concrete. Therefore, it is concluded that the surface improving agent developed in this research prevents deterioration of concrete durability when it is coated on the concrete structure.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.569-576
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• 2012

In general, aluminum alloys forms the passive film($Al_2O_3$, $Al_2O_3{\cdot}3H_2O$) in neutral solution. However, the passive film created on the surface will be destroyed by chloride ions contained in sea water so the corrosion will occur. In this study, in order to solve the problem of corrosion under a seawater environment, potentiostatic protection techniques were applied to Al-4.5%Mg-0.6%Mn aluminum alloy in seawater. At polarization experiments, active state were observed at anodic polarization and concentration polarization by reduction of dissolves oxygen and activation polarization were found at anodic polarization. As a results of potentiostatic experiment, calcareous deposit were created much more as applying time increase from the turning point of the concentration polarization and activation polarization and crevice corrosion was partially observed between calcareous deposit and surface of base metal. Overall potentiostatic anodic polarization experiment was difficult to apply potentiostatic corrosion protection technology by occurrence of active state, whereas potentiostatic cathodic polarization experiment examined optimum corrosion protection condition of -1.1 V~-0.75 V within the range of concentration polarization considered various applying time.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.179-186
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• 2017

This study was conducted to monitor the insecticidal susceptibility of western flower thrip, Frankliniella occidentalis, which damage horticultural crops in the Gyeonggi area. Bioassays were conducted under laboratory and greenhouse conditions by using the recommended concentrations of commercial insecticides being used for the control of thrips. Neonicotinoid insecticides, especially acetamiprid (8%) soluble powder (SP), clothianidin (8%) SC, imidacloprid (10%) wettable powder (WP) and thiacloprid (10%) water dispersible granule (WG) were not toxic to F. occidentalis collected from horticultural crops. However, F. occidentalis collected from vegetable greenhouses was extremely susceptible to acetamiprid + spinetoram (6 + 4%) suspension concentration (SC), clothianidin + spinetoram (6 + 4%) SC and methoxyfenozide + spinetoram (6 + 4%) SC, which resulted in over 90% control of thrips. In the greenhouse test, spinetoram (5%) WG, which caused 100% F. occidentalis mortality in the laboratory test, showed 87.4, 88.0, and 98.3% control at 3, 6, and 9 days after treatment, respectively, while imidacloprid (10%) WP showed below 44% control. From the results of this study, spinosin insecticides, such as more than over 4 and 10% of spinetoram and spinosad, and pyrrole insecticide, such as 5% chlorfenapyr, are recommended for the effective control of F. occidentalis.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.97-104
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• 2020

The present study conducted mock-up tests under the simulated sewage environments to examine the practical significance and limitation of coating materials that were previously developed on the basis of the bacterial glycocalix as a protection of concrete structures exposed to microbiological and sulphate attacks. The variations of the compressive strength and mass of the concrete due to the sulphate attack were measured using cylinder specimens. The bacteria growth and glycocalix formulation were calculated from the samples extracted from the sewage pipes. The next generation sequencing analysis was also conducted for environmental damage assessment due to the use of Rhodobacter capsulatus in the simulated sewage environments. The mock-up tests revealed that the developed coating materials have a good potential in resisting the sulphate attack, indicating no reduction on compressive strength and mass of the coated concrete under the sewage environment. At the age of 91 days, the concentrations of viable bacteria and glycocalix measured from the hardened coating materials were 1.4×10⁴cell/mL and 67.5mg/㎤, respectively. Moreover, harmful strains were not observed in the sewage water including glycocalix-coated concrete pipes. This implies that Rhodobacter capsulatus used in the coating materials does not influence negatively the microorganism cluster in the sewage environments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.97-103
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• 2020

The newly improved multistep steel pipe grouting method was applied to an existing steel pipe-reinforced grouting method. It was applied in order to prevent a damage caused by ground failure from excessive grouting pressure in a tunnel construction. The tunnel goes under a highway and a ramp connected to a rest area on OO highway with 11.3~12.1 m depth cover and is a part of roadbed facility construction section ordered by OO public corporation. The improved grouting method provides pre-construction work condition assessment technique through new water injection limit test and grouting effect assessment technique by grouting type assessment. It also includes assessments on interval of joints, appropriate grouting pressure, and optimal operation time to be applied to current operations. Application of the grouting method allowed the smooth road management in shallow-depth grouting construction area located upper part of tunnel excavation. Moreover, the possibility of the application of the method not only to shallow-depth grouting construction but also to various steel pipe-reinforced grouting constructions was confirmed.