• Journal of Environmental Science International
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• v.19 no.4
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• pp.491-507
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• 2010

This study focuses on the fauna, seasonal prevalence and altitudinal distribution of the flies from March to November, 2008 in Mt. Hallasan, Jejudo Island, Korea. The fauna of flies was 39 species belonging to 5 Families which consist of 12 Calliphoridae, 19 Muscidae, 5 Sarcophagidae, 1 Dryomyzidae 1, Scathophagidae and 1 Anthomyiidae. The total number of flies collected was 21,605 with sex ratio of 57.98% in Mt. Halla. The ratio is higher than that of the residential area and other mountain survey sites. The average number of per trap individuals collected on the trapping day is 267, which is similar with the average of Mts. Jiryong, Juwang, Palgong and Gumo. The five dominant species showed a distinctive seasonal prevalence of 92.6% of the total flies: Chrysomyia pinguis (34.2%), Calliphora lata (25.3%), Hydrotaea dentipes(23.1%), Fannia scalaris (5.1%), and Lucilia caesar (4.9%). The seasonal prevalence of the flies was from the beginning of March to the end of November, and the highest peak time of the whole flies, males and females were different respectively. In the similarity index of the flies collected in different altitude, that of between 1,000 meters and 1,500 meters was the highest among the indices of 500 meters and above 1,000 meters. The index at each altitude was above 80% because of the same area. The diversity index of fly species was between 0.00 and 0.88 through altitudinal traps monthly. The highest index in Trap 1 was 0.88 in October, in Trap 2, 0.82 in July and in Trap 3, 0.63 in July. The diversity above 1,000 meters was most various in July. The five dominant species of C. pinguis, C. lata, H dentipes, F. scalaris, and L. caesar showed distinctive seasonal prevalence, relative abundance and altitudinal distribution respectively.

• Journal of the Korean Society of Costume
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• v.61 no.3
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• pp.139-152
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• 2011

This research explores the idea of digilog for fashion; it would help to conclude the uncertain mixed-phenomena and words as a neologism and find a fundamental concept that would be a reference for a lot of uncertain new words that have been occurring even this year. Furthermore, this research is aimed at analyzing how digilog has been reflected on the contemporary fashion and directing the ways towards the future of fashion. The digilog fashion design is the expression of a combination of opposite extremes, that is to say the combination of a paradoxical mix and directly-opposed elements. The outward expression of fashion design with digilog can be classified into several ways. First of all, it tends to use the elements of paradoxical expression; for example, applying high-technology to express a primitive and natural material. The analog expresses unprocessed. Secondly, using high-tech machine to express the texture of handicraft or rough embroidery. Lastly, digital printing(DTP) is applied to enlarge the several or the whole parts of a natural object or sensitivity. As a result of the analysis, the inside view of the contemporary fashion with digilog delineate followings; it is the attitude that claims to go back to the past and accepts the combination of nature and high-technology to get calmness in the rapidly changing modern world. And it is the will to fly from the utterly exhausted reality through the recurrence of the past when there used to be a lot of energies and used to live in affluence.

• Journal of the Ergonomics Society of Korea
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• v.17 no.3
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• pp.13-22
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• 1998

Aircraft and the three-dimensional environment in which they operate are not user-friendly for human beings. As a result, maintaining the proficiencies necessary to safely and efficiently fly an airplane are difficult, and costly. The physiological and emotional status of the human element remains crucial in maintaining safe performance by all crew members. In the study of Hagiwara et al.(1993). they called the physiological and emotional status of the human element into the human alertness or physiological activity and stress, fatigue, circadian rhythm, alcohol. smoking, and self-medication are known the major factors that deteriorate the human alertness. Accordingly. this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applied. Throughout this experiment using performance test, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05~0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is expected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.

• Korean journal of applied entomology
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• v.4
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• pp.67-74
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• 1965

The work on the 'Studies of radiosensitivity' in Korea has been initiated since 1959 by the author at various institutions in home and foreign countries, and more than 20000 of plant materials in 73 varieties and 41 kinds are treated under varied conditions for the studies of radiosensitivity in plants. However, a study of the susceptibility to radiation in insect pests as well as their biological effects has not been previously reported in this country. During the year of 1964 and 1965, near 50000 of insects at the stages of adult, egg, larva and pupa in 14 different kinds are irradiated under acute X and gamma rays to investigate the behavior of growth and lethality after irradiation, and thrir general tolerances to radiations are compared by the kind of insects, stage of growth, radiation sources and exposured dosages. Through the experiments, it is shown that the lethality in most of insects are high as several kilo roentgens above and no significant effects on pupation. emergence, and oviposition in the treated generation at the dose of 3 Kr. below, but in the following generation , the rice stem borer for instance, no oviposition or decreased laying is observed from the dosages at 3 Kr. to 1 Kr., and the hatching was possible from 1.5 Kr. below of irradiated larvae although laying and hatching are seemed in normal. In general, the lethal dose $50\%$ of tested infect materials at the larval stage can he classified some what 60-80 Kr. for Pine caterpillar, Fall webworm, Camphor silk moth and their relatives, at 40-60 Kr. for Gypsy moth, Monley prominent and some relatives and at 20-30 Kr. for House fly, Rice weevil, Pine sawfly etc. Plant parasitic nematodes such as Hirschmannia and Paratylenchus shown very high resistance to radiation and the LD-50 is observed from 100 Kr. or above. A concept to evaluate the radiosensitivity in insects by taxological family line as a practical measure is not answerable yet, but it ran he solved within the near future through the continuing experiments.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.4
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• pp.45-52
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• 2019

Chemical grouting method is mainly used for construction of dams and reservoirs, stabilization and reinforcement of slopes, reinforcement of soft grounds such as embankments, dredging and landfills, the order of earthquake response method, and the reinforcement of structures. Recently, it is widely applied in construction sites such as highways, airfields, high-speed railways, subsea facilities, port construction works, tunnels, and subway works. As such, the demand for grouting continues to increase. The development of the grouting method was focused on increasing the strength of the ground, and the development of the chemical additives, the injection device, and the stirring device were mainly performed. But ordinary portland cement used for grouting is a product that consumes natural resources such as limestone, generates a large amount of greenhouse gases, consumes a large amount of energy sources, and it is time to develop products and new methods to replace them. In this study, Ordinary Portland Cement and New Grouting Binder (circulating fluidized bed boiler fly and blast furnace slag) were compared and analyzed by the following test. Homo-gel strength and homo-gel time, water quality analysis of the water used and soil contamination process tests of homo-gel samples were performed. In the case of NGB, when Using water is used as the reservoir water, the strength measured smaller than that of the other water. However, it shows about 2.5 times greater than the homo-gel compressive strength applied to OPC (7-day, reservoir water), so there is no problem with water quality when applied.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.8 s.227
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• pp.976-983
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• 2004

In high-density hard disk drives, the slider should be made to fly close to the magnetic recording disk to generate better signal resolution and at an increasingly high velocity to achieve better data rate. The slider disk interaction in CSS (contact-start-stop) mode is an important source of particle generation. Contamination particles in the hard disk drive can cause serious problems including slider crash and thermal asperities. We investigated the number and the sizes of particles generated in the hard disk drive, operating at increasing disk rotational speeds, in the CSS mode. CNC (condensation nucleus counter) and PSS (particle size selector) were used for this investigation. In addition, we examined the particle components by using SEM (scanning electron microscopes), AES (auger electron spectroscopy), and TOF-SIMS (time of flight-secondary ions mass spectrometry). The increasing disk rotational speed directly affected the particle generation by slider disk interaction. The number of particles that were generated increased with the disk rotational speed. The particle generation rate increased rapidly at motor speeds above 8000 rpm. This increase may be due to the increased slider disk interaction. Particle sizes ranged from 14 to 200 nm. The particles generated by slider disk interaction came from the lubricant on the disk, coating layer of the disk, and also slider surface.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.3
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• pp.167-173
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• 2018

In general, calcium is required for the reaction of blast furnace slag fine powder and fly ash. The by-products generated during the process of producing recycled aggregates have different calcium contents depending on the crushing stage and the possibility of using the process by-product as a concrete mixture is also different. In this study, the effect of the calcium content of the by-products on the compressive strength was investigated and the block was fabricated by using this. To utilize the by-products as an admixture, the calcium content was analyzed and the bending strength and surface temperature were measured according to the shape of the water storage block. As a result of this study, the possibility of making a block using recycled aggregate by-products was verified and arch type block was constructed to secure storage capacity and bending strength. Also, the surface temperature of the water storage block was reduced by $9^{\circ}C$ or more than that of the general permeable block.

• Journal of the Korea Concrete Institute
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• v.17 no.5 s.89
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• pp.735-742
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• 2005

The purpose of this study was to evaluate the salt water resistance of concrete depending on various types of cement. In this regard, 5 types of concrete were selected and their strength, void ratio and chloride ion diffusion characteristics were tested, and mutual correlation were analyzed. From the test results, the compressive strength and void ratio of concrete which using Type V cement was as good as Type I cement at long-term ages but the chloride diffusion coefficient of Type V cement was larger than Type I cement. And the concrete replacing some portion of the Type I cement with fly ash was superior in the cases of compressive strength, void ratio and the resistance of chloride ion permeation compared to the Type I cement with the lapse of ages. On the other hand, the compressive strength, the void ratio and the chloride diffusion coefficient of the concrete all indicated high levels of the correlation coefficient and the coefficient of determination regardless of the type of cement.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.601-604
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• 2008

This study as using admixture (G), high early strength agent, calcium hydroxide {a(OH)2} and fine particle cement, etc which have been newly developed for the purpose of quality improvements like the improvement of early strength of concrete that the FA was substituted by 20%, etc, reviewed the possibility of the utilization in the great quantity and the results are summarized as the followings. Slump loss by the kind of mixing material of high early strength agent and Ca(OH)$_2$ showed the smaller width of decrease than that of plain to appear the improved results and fine particle cement and G admixture showed the large slump loss. Air contents were appeared to satisfy the target air contents at all mixing materials. Regarding the compressive strength of the concrete by the kind of mixing material, G admixture was appeared to be highest all on aging 3 days, 7days and 28days at the initial strength. And fine particle cement and high early strength agent showed higher strength increase rate on aging 3days than plain but showed that the increase of strength becomes gradually dulled as aging is increased. And Ca(OH)$_2$ had almost no effect.

• Resources Recycling
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• v.22 no.3
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• pp.36-42
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• 2013

According to the recent community-based structures enlargement, specification, and diversification. It needs appropriate construction materials in terms of intensity and environmental aspects. Thus, in manufacturing the cement using micro limestone powder which is main material. It is also expected to save energies and reduces $CO_2$, by using the blast furnace slag and fly ash which are mitigated environmental load construction materials that emerged. In this research, The durability aspect tries to be grasped considering the chemical property according to the coherence of the hydration product. Consequently, The compressive strength was measured over 30 Mpa on 3rd. In addition, according to the content of the limestone powder, the setting time is promoted. It has the feature expanded in the length change. And it is determined because the possibility of replacing the existing for construction material such as it is measured compared with the time to use the portland cement usually that flexural strength is high with the age 7 days ago, so it is sufficient.