• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.53-64
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• 2015

This research was performed of high school science classes. These science classes progressed by using Scratch, and surveyed students' perception after finishing each class. This research was conducted of male students who want to choose department of natural science in the next grade. Those classes are consisted of four classes. This study produced a journal, and contained expressions of their thinking and feeling based on experiences during attending classes and projects. Consequently, that journal was analyzed in view of understanding and perception of Scratch using science classes, and it was also included of utilizing Scratch program. Research shows following three conclusions. First, students preferred Scratch using class to general one. They attend more active with high interest, and they felt senses of accomplishment while they make output by themselves. Second, their studies passed through three stages. These are problem perception, problem solving, and producing. Problem solving stage is especially complicated and difficult stage to students. This stage is consisted of Scratch side and Science side. Scratch side has Design and applying process, and Science side has data gathering and analyzing. Students' comprehension of scientific knowledge is increased and is preserved long time through this stage. Last, students had a hard time using Scratch. Because, it is the first time to them to use that program. Therefore, we deemed that they needed to start this kind of experience at lower grade than they are now, such as middle school stage. It is expected that this type of classes are getting more expanded and more populated as a part of students' core ability.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.196-202
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• 2006

Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However the most troublesome problem of lamivudine treatment is the emergence of lamivudine-resistant strains with amino acid substitution in the YMDD motif of DNA polymerase gene during the treatment. The aim of this study was to determine the mutation of YMDD motif (codon 552) and codon 528 in chronic HBV patients with lamivudine therapy using PCR-direct sequencing and to investigate the relationship between lamivudine mediated HBV mutation and HBeAg. HBV DNA was extracted from serum samples of HBV patients and amplified by nested PCR with two sets of primer pairs selected in HBV DNA polymerase gene. Amplified PCR product was analyzed by 2% agarose gel electrophoresis and direct sequencing. HBV mutation was detected in 124 out of 207 samples (60%). Single mutation was 50.8% for M552I, 43.5% for M552V, 5.7% for M552I/V and the L528M mutation was 67.0%. Double mutation was 43.6% for M552V/L528M, 33.1% for M552I/L528(wild type), 17.7% for M552I/L528M and 5.6% for M552I/V/L528M. Serine mutation at YMDD motif (M552S) was not found and the L528M mutation frequently accompanied M552V type. In this study, the typical difference of frequencies for HBV mutation depending on HBeAg was not found. Moreover, the PCR-direct sequencing method used in this study might be a powerful tool for the mutation study in clinical reference laboratories with high volume.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.285-297
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• 1993

For the application of the diffusion equation, slope height and maximum slope angle are calculated from the plotted slope profile. Using denudation rate as a solution for the diffusion equation, an apparent age index can be calculated, which is the total amount of denudation through total time. Plots of slope angle versus slope height and apparent age index versus slope height are useful for determining relative or absolute ages and denudation rates. Mathematical simulation plots of slope angle versus slope height can generate equal denudation-rate lines for a given age. Mathematical simulations of slope angle versus age for a given slope height, for equal denudation-rate at a particular profile site, and for comparing to other sites having controlled ages.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.312-320
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• 1993

Along with the fade out of the Cold War the world is undergoing a fundamental restructuring. The process is generally refered to regionalization and globalization. In this context, the Paper presents a geopolitical perspective on the future of Northeast Asia. To meet the global trend, it is expected that the countries in the area organize an economically cooperative unity, the concept of which the author calls the northeast Asian Rim (NEAR). With its huge potentials to become the largest economic area in the world and with its rather complicated historical and social background, the Rim is tentatively supposed to have a loose and soft organization, to be flexible in dealing with the intra-and interregional relations. The idea underlying the view is that the former area of confrontation between the land power and the sea power is, under the new world environment, going to recover its proper locational attributes and develop into a merging area, a new core. As a physical framework of the Rim a spatial structurc is assumed to consist of two-subrims and two development axes with four development centers.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.242-253
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• 2020

Six ornamental metal quiver fittings were excavated from stone chamber No.1 of the ancient tombs of Jeongchon, Bokam-ri, Naju. The ornamental quiver fittings are metal, but the body of the quiver was made of organic material, so that it corroded and disappeared in the burial environment. The ornamental metal quiver fittings were made in pairs, and decorated one quiver according to the location they were found in and their forms. The ornamental metal quiver fitting can be divided into two types: A band style ornament (帶輪狀金具) which decorates the arrow pouch, and a board style ornament (板狀金具) which decorates the board connecting the waist belt. Two ornamental metal quiver fittings excavated from wooden coffin 2 of stone chamber No.1, were made in the band style, while the ornamental metal quiver fittings from southeast of stone chamber No.1 were identified as two boardstyle ornaments and two band-style ornaments for what was presumed to be belt loops. Material analysis of the ornamental metal quiver fittings shows that they are made of a gilt bronze plate attached to an iron plate, and the surface is marked with a speck of chisel to make lines and patterns. Chemical composition analysis (XRF) established that 24~40wt% Au and 50~93wt% Cu were detected on the gold surface, and it was confirmed that bronze corrosion had taken place on the gilt surface. SEM-EDS analysis of the gold plating layer identified a working line for glossing, and 7~9wt% Hg and an amalgam of gilt layers was detected, confirming the amalgam gilding. CT and FT-IR analysis established that the band style was double-layered with silk fabric under the iron plate, and there was also a lacquer piece underneath. The band-style ornaments have two layers of silk under the iron plate, along with lacquer pieces. Adding the fabric to the arrow pouch increases adhesion and decorative value. It is assumed that the lacquer pieces indicate that the surface of the lacquered arrow pouch had fallen together with the ornaments. On the other hand, the board-style ornaments have a thick layer of organic matter under the iron plate, but this is difficult to identify and appears to be a remnant of the quiver board. The characteristics of these ornamental metal quiver fittings were similar in Baekje, Silla, and Gaya cultures from the late 4th to the late 5th centuries, and enable us to identify the art of ancient gold craftwork at that time.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.57-65
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• 2000

Objective of research is obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(wood-based materials) were analyzed. Proximate analysis showed the wood-based materials contains 0.37~2.27% ash, 70~74% volatile matter, and 17~20% fixed carbon. As carbonization temperature was increased, the charcoal yield was decreased. However, no difference in charcoal yield was found due to time increase. The specific gravity after the carbonization decreased about 30~40% comparing to green wood. The charcoal had 1.08~4.18% ash, 5.88~13.79% volatile matter, and 80.15~90.94% fixed carbon. The pH of plywood and particleboard(pH 9 at $400^{\circ}C$, pH 10 at $600^{\circ}C$ and $800^{\circ}C$) made charcoals was higher than that of fiberboard. The water-retention capacity was not affected by the carbonization temperature and time. The water-retention capacity within 24h was about 2~2.5 times of sample weight, and the Equilibrium moisture content(EMC) became 2~10% after 24h. EMC of charcoal from the thinned trees were 9.40~11.82%($20^{\circ}C$, RH 90%), 6.87~7.61%($20^{\circ}C$, RH 65%), and 1.69~2.81%($20^{\circ}C$, RH 25%). EMC of charcoal from the wood-based materials under $20^{\circ}C$, relative humidity(RH) 90% was similar to EMC of charcoal from the thinned trees(9~11 %). However, under $20^{\circ}C$, RH 25.65%, EMC of charcoal from the wood-based materials were higher(2~3%) than EMC of charcoal from the thinned trees. Every charcoal from the wood-based materials fulfilled the criteria in JWWA K 113-1947.

• Vending industry
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• v.2 no.5 s.6
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• pp.56-62
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• 2002

담배자판기의 신규설치를 금지하고 기존 설치된 자판기마저 전면철거하도록 하는 보건복지부의 초강력 규제안이 마침내 철회가 되게 되었다. 보건복지부는 올 들어 확대되는 금연정책에 편승, 기존 흡연 구역 내 담배자판기 신규설치를 금지하고, 기존 설치된 제품들마저 전면철거하는 규제를 담은 국민건강증진법 시행령 개정안을 지난 4월 공고하며 그 입법추진을 진행한 바 있다. 이 공고안은 그간 국무총리실 산하 규제개혁위원회 분과위원회에 상정되어 1,2차 심의를 진행해 오다 지난 9월 27일 본회의를 통해 '보건복지부의 흡연구역 내 담배자판기 신규설치 금지 및 기존 자판기 철거는 명백히 영업활동 자유 및 재산권 침해에 해당된다.'는 이유로 이를 철회토록 하는 결정을 진행했다. 이 결정을 담은 국민건강증진법 개정안은 조만간 법제처 심사 및 차관회의 등을 거쳐 최종 확정 되게 된다. 이같은 규제개혁위원회의 결정은 협회를 중심으로 한 산업의 적극적인 대응이 있었기에 가능했다. 성인인증장치 도입을 통해 청소년 흡연문제를 완전, 해결하겠다는 산업계의 적극적인 자율대책에도 불구하고 아예 담배자판기를 뿌리 채 뽑겠다는 보건복지부의 행정만능주의적인 발상은 도저히 수용하지 못할 부당한 처사라는 데 관련업계가 인식을 같이 했다. 따라서 이를 반대하는 산업계 입장을 분명히 하며 분명히 하며 적극적인 저지 대응을 최근까지 진행해 왔다. 협회에서는 1차적으로 보건복지부 건강증진과에 담배자판기 전면철거에 대한 산업계 반대 입장을 피력하는 소견서 제출하고 적극적인 산업계의 반대의지를 피력하는 작업을 진행했다. 또한 청소년보호위원회를 통해 청소년 흡연감소를 위한 성인인증 담배자판기 설치 활용방안 건의하며 담배자판기의 긍정적인 활용측면을 집중 부각시키기도 했다. 재정경제부를 통해서는 담배사업법 관련 담배자판기 설치기준에 대한 질의를 통해 현행 관련법 내에서의 설치기준을 명확히 하기도 했다. 이같은 대응에 있어서의 핵심 설득 논리는 담배자판기가 이제는 성인인증장치 부착을 통해 청소년 및 사회적 위해 요인을 극소화 할 수 있다는 점에 있었다. 과거와는 달리 담배자판기가 오히려 청소년의 담배 구입루트 차단이라는 긍정적 역할을 할 수 있는 시점에 있어 이를 전면규제하기보다는 합법적인 설치 환경을 확보하여 사회적으로 떳떳하게 존재가치를 평가받을 수 있게 해달라는게 산업계의 초지일관의 주장이었던 것. 협회는 이같은 주장이 결코 산업계의 이기만이 아니라 세계적인 추세라는 점, 또 담배자판기를 전면철거까지 하면서 과당규제를 할 명분이 부족하다는 점을 반대논리로 적극 내세웠다. 규제개혁위원회가 이번 공공 이용시설 중 흡연구역으로 지정된 장소 내에 담배자판기는 설치 금지 및 철거규제에 철회권고를 내리게 된 것은 이러한 산업계의 주장을 적극 수용함에 힘입은 바 크다. 규제개혁위원회는 이번 결정의 주된 이유로 우선 기설치된 자판기에 대한 철거는 재산권 침해로 위헌 소지가 있음을 들고 있다. 또한 흡연자를 위한 흡연구역내에서마저 자판기 설치를 금지하는 등의 규제는 과도하며 흡연자의 권익보호 역시도 필요함을 인정하고 있다. 따라서 전면적인 규제보다는 청소년 이용통제 가능한 흡연구역에 한하여 담배자판기를 설치토록한 현행규정의 실질적 관리를 강화하며, 전체적으로 흡연구역을 축소 제한하는 방향으로 추진함이 바람직하다는 의견을 제시했다. 규제개혁위원회의 이번 결정으로 흡연구역 내 담배자판기의 설치는 현행법의 적용을 받게 되며, 산업계의 자율대책대로 성인인증 장치를 부착한 담배자판기의 설치 확대가 크게 촉발될 수 있을 것으로 기대된다. 담배자판기가 적극적이고 능동적인 사회적 역할을 할 수 있을 때 자연 이를 반대할 수 있는 명분도 약해질 수 밖에 없다. 산업계는 보다 신뢰성 있게 청소년 이용을 차단할 수 있는 담배자판기 관련 기술 수준을 향상시켜야 할 것이며, 협회에서는 담배자판기의 공공성과 역할에 대한 지속적인 계몽 홍보를 통해 소비자 인식을 고양시켜 나갈 수 있게 해야 할 것이다. 비록 전면 규제 완화가 어렵고 힘든 길이기는 하지만 소비자에게 신뢰성을 부여하고 청소년의 담배 구입 루트 차단에 혁혁한 역할을 다할 수 있게 된다면 그 입지기반을 재평가 받을 수 있게 될 것이다. 담배자판기의 내일은 이제 암울함이 아닌 서서히 희망을 비치는 쪽으로 급선회되고 있다.

• Tunnel and Underground Space
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• v.22 no.4
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• pp.266-275
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• 2012

In this study, a method is devised to implement a supercritical $CO_2$ ($scCO_2$) injection environment on a laboratory scale and to investigate the effects of $scCO_2$ on the properties of rock specimens. Specimens of shale and sandstone normally constituting the cap rock and reservoir rock, respectively, were kept in a laboratory reactor chamber with $scCO_2$ for two weeks. From this stage, a chemical reaction between rock surface and the $scCO_2$ was induced. The effect of saline water was also investigated by comparing three conditions ($scCO_2$-rock, $scCO_2-H_2O$-rock and $scCO_2$-brine(1M)-rock). Finally, we checked the changes in the properties before and after the reaction by destructive and nondestructive testing procedures. The swelling of shale was a main concern in this case. The experimental results suggested that $scCO_2$ has a greater effect on the swelling of the shale than pure water and brine. It was also observed that the largest swelling displacement of shale occurred after a reaction with the $H_2O-scCO_2$ solution. The results of a series of the destructive and nondestructive tests indicate that although each of the property changes of the rock differed depending on the reaction conditions, the $H_2O-scCO_2$ solution had the greatest effect. In this study, shale was highly sensitive to the reaction conditions. These results provide fundamental information pertaining to the stability of $CO_2$ storage sites due to physical and chemical reactions between the rocks in these sites and $scCO_2$.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.99-128
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• 2018

The cultivation area of rice as staple grains is decreasing in the domestic situation in Korea. Import volume of a duty in foreign rice is 409,000 tons for a year regardless increasing of production per unit area and decreasing of rice consumption. The total stock of rice is increasing cumulatively despite the effort for production mediation of rice. Therefore, maintenance of cultivation area and reduction of production are necessary for national foodstuffs security problems. Development of environment-friendly and low-carbon technology as alternative of global warming and aging of farm labor power is very important responsibility for descendants with creation of sustainable agriculture environment. As alternative for demand and supply stabilization of rice from all angles, first stage: extension of environment-friendly cultivation area as 17% Jeollanam-do level with maintenance of cultivation area under the present circumstances, second stage: extension of environment-friendly cultivation area as 25%, third stage: extension of environment-friendly cultivation area as 35%. From above mentioned scenario, reduction of rice production (60,000 tons), increases of production cost (59,200,000,000 Won), and reduction of income (201,500,000,000 Won) are estimated in first stage. Reduction of rice production (90,000 tons), increases of production cost (122,100,000,000 Won), and reduction of income (313,700,000,000 Won) are estimated in second stage. Reduction of rice production (380,000 tons), increases of production cost (222,000,000,000 Won), and reduction of income (464,500,000,000 Won) are estimated in third stage. From analysis results for partial tillage in transplanting cultivation complex (10ha), rice production is decreased 1.3~1.5 ton by complex. Production cost of rice is decreased and increases of income cultivation type. Gradual extension of environment-friendly agriculture and low-carbon partial tillage could be expected for environment maintenance of the territorial integrity, confidence of consumer, and high-efficiency of low-cost.