• Journal of The Korean Association For Science Education
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• v.4 no.1
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• pp.1-14
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• 1984

The student's attitude toward science is generally influenced by their teachers. Therefore, teachers' positive attitudes toward science and science teaching play an important role to change the student's attitude toward science. The purpose of this survey is to investigate the status on attitudes toward science and science teaching among the secondary school science teachers in Korea. The attitudes were surveyed by the questionnaire which was developed by Sung-Jae Pak. The instrument is designed to use Likert type scale and is composed of two kinds of scale: one is the attitudes toward science scale (the AT scale) and the other is the attitudes toward science teaching scale (the AT Kale), which contains 24 questions respectively. Each of them has 6 sub-level areas. The six areas of attitude toward science are as follow: The goals and values, process and method of science, knowledge and the view of nature, social and cultural aspects, scientist and a career in science, the preferences and willingness. The six areas of attitude toward science teaching are as follow: The goals and values, process and method of science teaching, the content and structure, social and cultural aspects, science educator and a career in science teaching, satisfaction and willingness. From 152 teachers' responses, the tendency of total as well as each area and the contrast of their backgrounds at the level of 5% significance were analyzed by SPSS computer program. Some results and conclusion of the study are as follow: 1. The overall attitude of the measured secondary school science teachers shows a positive trend tendency. Also total positive attitude toward science teaching are slightly higher than that of science, which support the fact that the teachers are not scientists but they are directly involved in teaching of science. 2. The attitudes toward science are moderately correlated to the attitudes toward science teaching (r=0.52). 3. The areas of knowledge, nature-view and tile area of social aspects of science show a very negative tendency. Also the two areas are not correlated to some other areal at the level at 5% significance. 4. Female science teachers exhibit just a little more positive attitudes than those of male teachers in science teaching. 5. The science teachers who wanted to have a profession of scholar or educator exhibit a little more positive attitudes than others in science and total attitudes (AS+AT). 6. The more the science teachers have "intellectual delights" the more their attitudes toward science and science teaching are positive. 7. At the level of 5% significance, there are differences which college they graduated from, but there are no differences in multiple comparison at 10% level. 8. The differences in their background dose not appear in such as age; teaching career; academic career; deny the superstition; their onlook for the scientist or educator when they were freshmen; major the basic science; opinions about the U.F.O. and the origin of life. 9. The responses of certain individual statement are quite different from the overall tendencies, which strongly suggest the de1ailed analysis and deeper study. For the continuing study, it is recommendable to revile the measuring tools with the theoretical study for the better validity and reliability, and investigate the status of the attitudes toward science and science teaching among the science teachers with sufficient samples.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.332-338
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• 2012

Soil compaction is one of the major problems facing modern agriculture. Overuse of machinery, intensive cropping, short crop rotations, intensive grazing and inappropriate soil management leads to compaction. This study was carried out evaluate of the effects soil texture and different compaction levels within the soil profile on the soybean root growth and productivity. The soybean plants were grown in $21cm{\o}{\times}30cm$ cylinder pots using three different soil textures (clay, fine loamy and coarse loamy) compacted at different compaction levels (1.25, 1.50, 1.75, and 2.00 MPa). Results revealed that soybean development is more sensitive on penetration resistance, irrespective of soil type. Soybean yield and root weight density significantly decreases with increasing levels of soil compaction in both clayey and fine loamy soils, but not in coarse loamy soil. The highest root weight density was recorded in coarse loamy soils, followed by fine loamy and clay soils, in descending order. The root growth by soil compaction levels started to decline from 1.16, 1.28 and 1.60 MPa for clay, fine loamy and coarse loamy soils. Soybean production in the field experiment decreased about 30% at compacted sub-soils compared to undisturbed soils.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.643-656
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• 2005

The East Sea, a marginal sea or back-arc basin, consists of Japan Basin, Yamato Basin, and Ulleung Basin and is surrounded by the Pacific Plate and Philippine Sea Plate. Ulleung Basin locates in the southwestern part of the East Sea and shows the depth of 1,500 m in average and 2,500 m in maximum, connecting to the Japan Basin along 2,000 m contour. The slope of the seafloor is greater in the western side of the basin than in the southern and the eastern side. The crustal thickness of the Ulleung Basin from the OBS tends to get thicker toward the north and the west side and the sediment thickness of the Ulleung Basin is getting thicker toward the southeast side and reaches up to 12 km. The crustal type of the Ulleung Basin was variously suggested as like as a rifted continental crust, an extended continental crust, and an incipient oceanic trust. The origin of the crustal formation and the Ulleung Basin, however, is still controversial. Based on the bathymetry and gravtiy anomaly data for this study, the axis of the Ulleung Basin shows that the basin develops along the axis trending NW-SE direction and reveals a general symmetry of the bathymetry. And also the free-air gravity anomalies show a very similar pattern to the bathymetry of the basin. The sediment thickness is relatively thicker in the southeastern side of the basin than in the northwestern side. Although the crustal age of the Ulleung Basin is supposed to be younger than them of the Japan Basin and the Yamato Basin, the free-air gravity anomalies of the Ulleung Basin ranging -40 to 50 mGals are lower than the other basins, which suggests that the densities of crust and sediment of the Ulleng Basin are lower than the Japan Basin and the Yamato Basin.

• Journal of The Korean Association For Science Education
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• v.23 no.3
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• pp.286-298
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• 2003

The purpose of this study was to analyze scientific thinking types and processes generated in inductive inquiry by college students. Subjects were three college student. Three inductive tasks were developed: Caminalcules set I which is a task consisted of 6 imaginary animals, a potato task which is a task about the interaction between juiced potato and $H_2O_2$, and Caminalcules set 2. Subjects' thinking types and processes were investigated through thinking-aloud method and interview. Subjects' performances were recorded on videotapes and analyzed. Subjects have shown 5 types of inductive thinking in the first task; observing, discovering commonness, discovering pattern, classifying, discovering hierarchy. The processes of inductive thinking shown by students are followed; observing $\rightarrow$discovering commonness $\rightarrow$classifying $\rightarrow$discovering pattern $\rightarrow$discovering hierachy. The subtypes of inductive thinking on observing were investigated by the analysis of subjects' performance on the second task. In analysis of protocol, student' thinking types on observing have been classified as simple observing and operational observing. Operational observing has been categorized conjectural observing and predictive observing. The subtypes of inductive thinking on classification and hierarchy were investigated by the analysis of subjects' performance on the third task. In analysis of protocol, students' thinking types on classification have been searching criteria for classifying and selecting criteria for classifying. Subtypes of discovering hierarchy have been classifying groups and hierarchical ordering by students. Processes of classifying groups proceeded from searching criteria for classifying to selecting criteria for classifying.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.57-68
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• 1983

To estimate the possible amount of weed-crop competitions under the various cropping patterns of two rice cultivars of different type, comparisons between weedy check and weed-free plots in plant height, tillering number, and plant weight were investigated. Fluctuations in Importance Value, competition value, and net productivities were used to discuss the crop-weed competition, respectively. As a result, differences in dominant weed species, competitive crop variety, most effective cropping pattern, and crop yielding characteristics under the different weed competitions were investigated, respectively.

• Journal of Life Science
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• v.21 no.5
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• pp.720-728
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• 2011

Garlic (Allium sativum) has been used as a source food as well as a traditional folk medicine ingredient since ancient times. Aged black garlic is a type of fermented garlic and is expected to have stronger anticancer and antioxidant activities than raw garlic. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis are poorly understood. In the present study, the effects and mechanisms of water extracts of raw garlic (WERG) and aged black garlic (WEABG) on adipocyte differentiation and adipogenesis in 3T3-L1 preadipocytes were investigated. Treatment with WEABG significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet number and lipid content through Oil Red O staining, however WERG had no such effect. In addition, WEABG reduced accumulation of cellular triglyceride, which is associated with a significant inhibition of key pro-adipogenic transcription factors including peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins ${\alpha}$ (C/EBP${\alpha}$) and C/EBP${\beta}$. Taken together, these results provide important new insight that aged black garlic might inhibit adipogenesis by suppressing the pro-adipogenic transcription factors in 3T3-L1 preadipocytes, and further studies will be needed to identify the active compounds that confer the anti-obesity activity of aged black garlic.

• The Journal of the Petrological Society of Korea
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• v.9 no.2
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• pp.99-118
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• 2000

The variation of Na(A), K, Na(M4), A l O and Al(VI)+Fe3++Ti+Cr in the zonal amphiboles from the amphibolites of the Hwanggangri area indicates that the tschermakite-, edenite- and glaucophane substitutions are higher in the rim than in the core, in which actinolite changes to hornblende with going outward from core to rim. The contents of substitutional elements of hornblende~ of three samples@l29-2, M76-2, M78), which include diopside and greenish brown hornblende and are thought to represent the highest metamorphic grade, are lower than those of rim homblendes of the lower metamorphic grade and are higher than those of core actinolite that they conform to the middle domain in those of the whole amphiboles. Considerations about the origin of zonal amphiboles are as follows. Firstly, two samples(R102-1, R210-9) have the same amphibole composition like core is actinolitic hornblende, and rim is magnesian hastingsite although plagioclases such as albite(R102-1) and labradorite (R210-9) show the wide compositional difference. It is impossible to produce both albite and labradorite by one metamorphic event. Judging from this wide compositional difference, the existence of zonal amphiboles does not indicate the miscibility gap but is thought to be the result of the polymetamorphism. Secondly, the crystallographically sharp and gradational interfaces between actinolite and hornblende fonned in the amphibolites rgardless of the distance from the granite. In case of the samples(R210-9, M128, M130) having the sharp interface between two amphiboles, the plagioclase show the compositions produced at the low grade and the medium grade. Because such variable compositions of plagioclase indicates the overprinting of metamorphism of higher metamorphic grade than that of the formation of miscibility gap, it implies that zonal amphiboles were formed by polymetarnorphism. In case of the gradational interface between two amphiboles, this texture is also thought to be the effect of polymetamorphism from the fact that this texture mainly occur near the granite and from the consideration of the metamporphic grade. The relationship between the compositional variations of the amphiboles and the pressure types of metamorphism suggests that actinolitic core is considered to be grown by the metamorphism of medium pressure, while hornblende rim is shown to have genetic relations with the metamorphism of low pressure type.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.185-197
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• 1995

Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.44-49
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• 2004

Changes in quality properties of Kochujang prepared with Paecilomyces japonica powder and extract using different solvents were investigated during 90 days of fermentation at $20^{\circ}C$. Although moisture contents were not significantly different, pH of P. japonica-added Kochujang was lower than that of control group without P. japonica, and decreased with increasing fermentation time. Amino nitrogen content increased up to 60 days of fermentation and decreased slightly after 90 days, with that of P. japonica-added Kochujang showing highest on 30 and 60 days at 179.2 and 282.2 mg%, respectively, higher than control gruup. L, a, and b values decreased in proportion to fermentation period, with P. japonica-added Kochujang, particularly P. japonica powder-added Kochujang, lower than those of control g개up. Sensory evaluation test showed color of control group was 'clear red', whereas that of P. japonica powder-added Kochujang was 'dark reddish brown' and P. japonica extract-added Kochujang was darker than control group; consumer preference for dark color was low, Textures of all samples were 'glossy and smooth', showing high consumer preference. Salt content of P. japonica-added Kochujang was higher than that of control group, with P. japonica extract-added Kochujang higher than that made with powder Hot taste or P. japonica-added Kochujang was weaker, whereas its flavor higher, than control group, with P. japonica powder-added Kochujang showing highest flavor score. Overall preference was higher for P. japonica-added Kochujang than control group, with P. japonica water extract-added Kochujang showing the highest score.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.319-326
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• 2003

Angiotensin-I converting enzyme(ACE)inhibitor was isolated from beef by-products. The beef by- product hydrolysates prepared with various proteases were tested for the inhibitory effects against ACE. The proteases used were proteinase A from bakers yeast, protease type ⅩIII fungal and thermolysin. The maximum inhibitory effect was observed after hydrolysis for 12hrs(beef heart) and 24hrs(beef spleen), respectively. After gel filtration, IC50 value was 0.37mg/ml in beef heart and 1.84mg/ml in beef spleen. After RP-HPLC, the IC50 value of peak 1, peak 2, peak 3 and peak-4 were 0.28mg/ml, 0.26mg/ml, 0.25mg/ml and 0.35mg/ml, respectively. In the results of amino acid composition of peak 1, peak 2, peak 3 and peak 4, it was observed that peak 1 was consisted mainly of glycine and methionine, peak 2 was proline, cystine and methionine, peak 3 was proline and peak 4 was alanine, methionine and leucine. In conclusion, beef heart hydrolysate treated with thermolysin+ proteinase A was shown to have the highest inhibitory effect for 12hrs incubation at 37$^{\circ}C$.