• 한국환경과학회지
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• 제25권3호
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• pp.345-359
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• 2016

This study analyze the synoptic meteorological cause of rainfall, rainfall intensity, drop size distribution(DSD), fall velocity and oblateness measured by the 2D-Video distrometer(2DVD) by comparing two cases which are heavy rainfall event case and a case that is not classified as heavy rainfall but having more than $30mm\;h^{-1}$ rainrate in July, 2014 at Gimhae region. As a results; Over the high pressure edge area where strong upward motion exists, the convective rain type occurred and near the changma front, convective and frontal rainfall combined rain type occurred. Therefore, rainrate varies based on the synoptic meteorological condition. The most rain drop distribution appeared in the raindrops with diameters between 0.4 mm and 0.6 mm and large particles appeared for the convective rain type since strong upward motion provide favorable conditions for the drops to grow by colliding and merging so the drop size distribution varies based on the location or rainfall types. The rainfall phases is mainly rain and as the diameter of the raindrop increase the fall velocity increase and oblateness decrease. The equation proposed based on the 2DVD tends to underestimated both fall velocity and oblateness compared with observation. Since these varies based on the rainfall characteristics of the observation location, standard equation for fall velocity and oblateness fit for Gimhae area can be developed by continuous observation and data collection hereafter.

• Environmental Analysis Health and Toxicology
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• 제20권2호
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• pp.153-159
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• 2005

In order to evaluate the physical and mental health status of airline flight attendants, 136 airline flight attendants were given a general health questionnaire (Todai Health Index), and the prevalence of their subjective complaints was measured. Collected data were classified according to age distribution, length of employment, service area, smoking status, job satisfaction, gender, and marital status. The results obtained were summarized as follows: 1 The scores of health complaints of physical items were higher in the oldest group $(age 50\~60)$ than in younger groups. The THI eye and skin symptom scores were significantly higher for the oldest groups than for the younger groups. 2. The health complaints scores of physical items were higher in the long-length employment group (more than 5 years), whereas most scores of mental items were higher in the short- length employment group (less than 2 years). The THI mouth and anus scores for the long-length employment group were significantly higher than for groups of workers who had been employed for a shorter time. 3. THI scores were higher for domestic airline crews, dissatisfied workers and females. 4. The irregular life THI score was significantly higher among domestic crews than international crews. 5. The impulsiveness and depression scores were significantly higher in the dissatisfaction group. 6. The female group showed higher scores in the multiple subjective symptoms, mental irritability, depression, and irregular life categories. 7, The THI scores of the mouth, anus and nervousness were significantly higher for the married group than for the unmarried group. In summary, this study shows that the health complaints scores of physical and mental symptoms tended to be higher among the aged group, domestic airline crews, the dissatisfaction group, and females. These results can be used for improving the psychosomatic health status and working environments of flight attendants.

• The International Journal of Costume Culture
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• 제4권2호
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• pp.77-85
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• 2001

The purpose of this study was to classify the somatotype around a upper body of 30's men. The subjects were 202 working men aged from 30 to 39 and the data of 33 items including computed items were analysed by factor analysis and cluster analysis. Re results were as follows: As a factor of somatotype in evaluating males in 30's, the horizontal area represented the chest circumference at scye and the breadth items, the vortical region indicated hit length posterior, front length, back length, the breadth difference and the length difference. The somatotype by cluster analysis was classified with 3 type. Type I as the Roher's index 1.21 indicating the smallest in the circumference and weight item was classified as the thin and long featuring bending somatotype. Type 2 with the Rohrer's index 1.35 showing the mid-group between type 1 and 3 had the highest distribution rate as the balanced featuring the standard somatotype. Type 3 as the rohrer's index 1.40 was the largest physical condition group in the obesity featuring the turning over somatotype.

• Journal of Forest and Environmental Science
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• 제28권1호
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• pp.1-7
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• 2012

Tropical forests whether fragmented or undisturbed or be they equatorial or deciduous, remain the storehouse of biodiversity for hundreds of thousands of plant and animal species. This unique characteristic continues to attract a wide range of scientists and international organizations to study and attempt to understand tropical forest ecosystems. Gene flow is mediated by pollen, seed and seedling dispersal, and factors affecting this gene flow include phenology, spatial distribution, population structures, seed predation, sexual and mating systems as well as physical and biological barriers to gene flow. Two methods are used in measuring gene flow: direct method that relies on the actual observation of seed and pollen dispersal, whereas indirect methods involve the use of genetic markers such as allozymes and DNA techniques. Political strife, extreme natural and artificial disasters, the lack of a comprehensive forestry research vision, coupled with difficult socio-economic conditions in Africa have made the environment quite difficult for sustained research activities on the part of those undertaking or wishing to undertake such studies. Gene flow studies in this region are few and far between. This review elaborates on the mechanisms of gene flow mediation in Sub-Saharan Africa.

• 농업과학연구
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• 제43권4호
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• pp.507-521
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• 2016

Landslides are one of the most common natural hazards causing significant damage and casualties every year. In Korea, the increasing trend in landslide occurrence in recent decades, caused by climate change, has set off an alarm for researchers to find more reliable methods for landslide prediction. Therefore, an accurate landslide-susceptibility assessment is fundamental for preventing landslides and minimizing damages. However, analyzing the stability of a natural slope is not an easy task because it depends on numerous factors such as those related to vegetation, soil properties, soil moisture distribution, the amount and duration of rainfall, earthquakes, etc. A variety of different methods and techniques for evaluating landslide susceptibility have been proposed, but up to now no specific method or technique has been accepted as the standard method because it is very difficult to assess different methods with entirely different intrinsic and extrinsic data. Landslide prediction methods can fall into three categories: empirical, statistical, and physical approaches. This paper reviews previous research and surveys three groups of landslide prediction methods.

• 한국환경과학회지
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• 제8권2호
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• pp.249-254
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• 1999

The biosorption and desorption of Cd were carried out using brown marine algae, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by the physical and the chemical pretreatment of Sargassum fluitans biomass. The Cd uptake was independent of the alginate content. In case of protonated biomass, Cd uptake was the lowest because the alginic acid of biomass was dissolved to cadmium solution during the biosorption. The maximum Cd uptake of Sargassum biomass was ranged from 79 mg/g to 139 mg/g. In case of raw biomass, the higher the alginate content of biomass, the higher was the Cd uptake. 100% of Cd and light metals sorbed in the biomass were eluted at 0.1N HCI(pH 1.1). However, the elution efficiency in $CaCl_2$ and $Ca{(NO_3)}_2$solution was varied by the concentration, the solid to liquid ratio and the pH of calcium solution. The distribution coefficient between Cd and protons in the desorption solution at pH ranged from 1.6 to 2.9 was observed on the constant stoichometric coefficient(1.3).

• 한국축산식품학회지
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• 제29권4호
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• pp.513-522
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• 2009

HACCP is a scientific and systematic program that identifies specific hazards and gives measures for their control to ensure the safety of foods. Based on the Livestock Products Processing Act, the HACCP system is now being applied to Korean livestock products since December 1997, and Korea is accelerating its application from farm to table, including in farms, slaughterhouses, livestock product industries, retail markets, and transportation. The transport of livestock and its products is one of the vulnerable sectors in terms of food safety in Korea. Meats are transported in trucks in the form of carcasses or packaged meats in boxes. Carcasses may be exposed to microbiological, physical, and chemical hazards from the environment or through cross-contamination from other meats. Poor cleaning or maintenance of vehicles and tools may also raise the exposure of carcasses to microbiological or chemical hazards. HACCP application and its acceleration in distribution, particularly in transport, is regarded as critical to the provision to consumers of ultimately safe livestock products. To achieve this goal, steady efforts to develop practical tools for HACCP application should be carried out.

• 한국환경과학회지
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• 제5권4호
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• pp.535-544
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• 1996

In the development of Molten Carbonate Fuel Cell, one of the serious problems is the dissolution of cathode material. Therefore, the development of the alternative cathode which is stable in molten carbonate is needed. In this research, the licoo, was chosen as alternative cathode material. $LiCoO_2$ powder was synthesized by high temperature calcination method and by citrate sol-gel method. And its structure and physical iharacteristics were analyzed by XRD, 1 R, TCA and porosimeter. The conductivity and solubility of $LiCoO_2$ electrode were also measured. Homogeneous $LiCoO_2$ Powder was obtained by citrate sol-Rel method at 445$^{\circ}C$, however, obtained above 75$0^{\circ}C$ by high temperature calcination method. Homogeneous particle size distribution and fine powder were obtained by the citrate sol-Rel method. $LiCoO_2$ electrode showed higher electric conductivity ($1.7 $\Omega$^{-1}cm^{-1}$) than NiO (0.1 $\Omega$^{-9} cm^{-1}) at $650^{\circ}C$. The solubilities of $LiCoO_2$ electrode in electrolyte were varies 0.6 to 1.0 ppm during 200 hours. So, the solubilities of $LiCoO_2$ were much lower than that of NiO.

• 한국환경과학회지
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• 제16권8호
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• pp.929-939
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• 2007

Red mud is a waste generated by the aluminium industry, and its disposal is a major problem for this industry. Red mud has a reddish-brown color and superfine particle characteristics. So, it can be a promising pigment admixture for concrete industry. An experimental study was conducted to investigate the potential use of red mud in color concrete. The micro structures of red mud and iron oxide pigment such as porosity, pore size distribution, diameter of particle were analyzed with the aid of SEM, X-ray diffraction(XRD), and the infrared absorbance. Tests on physical properties of color concrete, such as strength, slump, early shrinkage crack patterns, and color characteristics were carried out and the results were reported in this paper.

• 한국도로학회논문집
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• 제17권6호
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• pp.97-104
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• 2015

PURPOSES : Expressways experience chronic and recurring congestion, especially during weekends and holidays, because of the increased demands for leisure-related travel. The alternatives to solve chronic and recurring congestion may be three-fold: (1) physical expansion of expressway capacities, (2) road pricing, and (3) temporal and spatial distribution of traffic demands. Among these, the third alternative may be the most cost-effective method for the Korea Expressway Corporation (KEC) that can be achieved by using the existing ITS infrastructure. METHODS : KEC initiated a pilot study in which the traffic on congested expressways was managed by providing traffic condition information (i.e., travel times) of neighboring national highways for taking detours via variable message signs (VMS). This study aimed to estimate the detour rate, and the two pilot studies on Seohaean and Yeongdong expressways yielded many benefits. RESULTS : It was revealed that the total length of congestion segments decreased by 7.8 km, and the average travel speed increased by 5.3 km/h. CONCLUSIONS : Based on these findings, it was concluded that the propagation of detour information via VMSs during congestion hours can help reduce congestion on expressways and increase the benefits of the entire network.