• Journal of Korean Elementary Science Education
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• v.41 no.1
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• pp.150-161
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• 2022

Matter is a basic concept that students should understand during their science classes. However, many difficulties are associated with understanding the concepts of matter due to its abstraction. In this study, the elementary school students' understanding of the concept of matter and the examples of matter and non-matter are investigated and analyzed by grade. The subjects of this study were 418 students from third grade to sixth grade. The survey was conducted using a free-response questionnaire comprising three questions. The results are as follows. First, the elementary school students' conceptions of matter were "materials that make up objects," "what can be seen and touched," and "solid, liquid, and gas." As the grade increased, the explanations for a material decreased and the explanations for the state of matter increased. Furthermore, only few students explained matter in terms of mass and volume. Second, solids were the most common examples of matter presented by the students, and liquids and gases were included in the upper grades. However, there were many cases in the upper grades where students were unable to distinguish between objects and matter. Third, non-matter was properly presented by the 6th graders as compared to the other graders, and in many cases, objects, liquids, and gases were mentioned as non-matter. Fourth, it was found that the students' conceptions of matter influenced the examples of matter and non-matter that they presented.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.1-10
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• 1982

This study was conducted to determine effect of fruits removal on the CO2 exchange rates (CER) and growth of ginseng plant. Fruit of 2, 4 age plant removed at 7, May. The results of these investigations are as follows. 1. The net photosynthetic rates of the ginseng bearing fruits increased to a considerably greater degree than that of the ginseng without fruit in each ages. 2. The total dry matter per plant in bearing fruit (40.24g) had produced more dry matter than that of non-fruiting plant (38.13g) , but the root 4.y matter in fruiting plant (26.2g) had produced less dry matter than that of non-fruiting plant (27.1g) in 4 age. 3. The ginseng plant in bearing fruit did not influence the dry matter of stem and leaf. 4. The maximum RGR of root (17, June) was slower than that of fruit (4, June) .

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.19
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• pp.169-190
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• 2003

Uniform Computer Information Transactions Act (UCITA) for e-commerce in non-UCC and non-UETA transactions, promulgated in 1999. The Act Drafted by the National Conference of Commissioners on Uniform State Laws. UCITA applies to contracts to license or buy software, contracts to create computer programs, contracts for on-line access to databases and contracts to distribute information over the Internet. UCITA does not apply to goods such as television sets, stereo equipment, airplanes or traditional books and publications. Goods generally remain subject to UCC Article 2 or Article 2A. Many transactions may include more than computer information. If that transaction covers non-goods subject matter, UCITA applies only to the part of the transaction which is computer information and other law applies to the other subject matter. In the event the other subject matter is goods, UCC Article 2 or 2A applies to the goods subject matter and UCITA applies to the computer information part. UCITA is coordinated with existing Articles 2 and 2A, so coverage of each to part of the transaction will be facilitated. With respect to other subject matter (primarily services) UCC Articles 2 and 2A have worked in mixed transactions with the common law applicable to the services.

• Journal of Korean Society on Water Environment
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• v.34 no.5
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• pp.487-493
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• 2018

Urban stormwater runoff is the one of the most extensive causes of deterioration of water quality in streams in urban areas. Especially, in the Suyeong River watershed, non-point sources from urban-residential areas are the most common cause of water pollution. Also, it has been ascertained that BOD and COD as indexes of organic matter, have limitation on management of Suyeong River's water quality. In this study, changes of organic matter properties of Suyeong River from inflow of non-point source during rainfall were investigated. Fractions of organic matters were analyzed using water samples collected at two sites (Suyeong River and Oncheon Stream) during a rain event. Variations of dissolved organic carbon (DOC) concentration by rainfall were similar to flow rate change in the river. Distribution of organic matter fraction according to change of rain duration revealed that while hydrophilic component increased at initial rainfall, the hydrophobic component was similar to change in dissolved organic carbon (DOC) concentration. Also, the relative proportion of hydrophilic components in organic matter in river water increased, due to rainfall. Results of biodegradation of organic matters revealed that decomposition rate of organic matters during rainfall was higher than that of during a non-rainfall event.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.496-504
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• 1996

The study was conducted to obtain the basic information on increasing aromatic degrees by shading and organic matter application on Condonopsis lanceolata. The result were as followings : Fresh root wt. in shading 55 % treatment was increased about twices, whereas fresh root weight in non-shading was decreased. But growth of ground parts such as vine length, leaf width, and leaf number was promoted under non-shading treatment. Macroelements such as K, Ca, and Mg, were increased in non-shading and higher organic matter application. The components such as crude protein, fiber, and ash were increased in the shading 55% treatment compared with non-shading. In the sixteen amino acids, arginine contents were the highest in non-shading and organic matter 30M/T. Recovery yield of essential oil was 0.005% in non-shading. The highest was organic matter 30M/T in the non-shading as 0.007%. Major aromatic constituents were 11 kinds of aliphatic alcohols such as I-hexanol, cis-3-hexenol, and trans-2-hexanal. As a result, major aromatic degree was higher in shading 55%, also increased in the much organic matter application. It was considered to be applied dense shading 55% and much organic matters to produce Condonopsis lanceolata plants which have high aroma and good quality.

• Journal of Korean Society on Water Environment
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• v.27 no.4
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• pp.433-437
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• 2011

The study is conducted to evaluate loading of organic matter as seasonal changes during non-storm period into Lake Paldang which is used to a major drinking water source. Samples were taken in Lake Paldang intake during non-storm period and were analyzed loading of organic matter. From the results of the survey, improving of the water quality showed remarkable tendency depending on the changing periods from summer to fall and from fall to winter. Dilution effect from the increase of base run-off caused by the concentrated rainfall in rainy season, the characteristics of Korea's climate seems to have to be the reason. On the other hand, deteriorating of the water quality showed tendency depending on the changing periods from winter to spring and from spring to summer. Increase of Cyanobacteria etc. is explained by seasonal effects which are a small amount of the rainfall in winter and spring and gradational increase of water temperature.

• Animal Bioscience
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• v.37 no.7
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• pp.1185-1195
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• 2024

Objective: This meta-analysis aimed to evaluate the impact of wilted and unwilted silage on various parameters, such as nutrient content, fermentation quality, bacterial populations, and digestibility. Methods: Thirty-six studies from Scopus were included in the database and analyzed using a random effects model in OpenMEE software. The studies were grouped into two categories: wilting silage (experiment group) and non-wilting silage (control group). Publication bias was assessed using a fail-safe number. Results: The results showed that wilting before ensiling significantly increased the levels of dry matter, water-soluble carbohydrates, neutral detergent fiber, and acid detergent fiber, compared to non-wilting silage (p<0.05). However, wilting significantly decreased dry matter losses, lactic acid, acetic acid, butyric acid, and ammonia levels (p<0.05). The pH, crude protein, and ash contents remained unaffected by the wilting process. Additionally, the meta-analysis revealed no significant differences in bacterial populations, including lactic acid bacteria, yeast, and aerobic bacteria, or in vitro dry matter digestibility between the two groups (p>0.05). Conclusion: Wilting before ensiling significantly improved silage quality by increasing dry matter and water-soluble carbohydrates, as well as reducing dry matter losses, butyric acid, and ammonia. Importantly, wilting did not have a significant impact on pH, crude protein, or in vitro dry matter digestibility.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.356-360
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• 2000

With isogenic waxy and non-waxy rice cultivars, growth responce as affected by leaf-removal treatment were examined in various fertilizer application. Vertical dry matter of culm was significantly decreased from ground upto 10cm. Culm dry matter of waxy rice was more steadily decreased than that of non-waxy rice. Starch content of culm in non-waxy rice was higher than waxy rice, and that in waxy and non-waxy rice were the lowest in three leaf-removal but no difference in single leaf-removal. Flag leaf in waxy rice and 2 nd leaf in non-waxy rice were dominantly affected yield by leaf-removal. The 1000-grain weight and rippend grain ratio of non-waxy rice were more higher than waxy rice and that in waxy and non-waxy rice were the lowest value in three leaf-removal but no difference in single leaf-removal treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.215-218
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• 1996

This study examines the possibility of early production of forage rape (cv. Akela and Velox) in the period of wintering. Bolting date was Feb. 2 to Feb. 9 in PE film house culture by non-heating and Mar. 3 to Mar. 12 in open field culture. And flowering date was Feb. 24 to Mar. 3 in PE film house culture by non-heating, so it was 30~50 days faster than the open field culture of Apr. 17 to Apr. 22. Fresh matter yield was 8, 356~4, 887 kg/10a in PE film house culture by non-heating, so it was 1, 431~1, 603 kg/10a yield increase than in the open field culture of 7, 253~7, 456 kg/10a Dry matter yield was 953~963 kg/10a in PE film house culture by non-heating, so it was 71~284 kg/10a yield increase than in the open field culture of 669~892 kg/10a.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.2
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• pp.35-42
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• 2001

The diesel engine exhaust gas is know as one of the causes to produce photochemical smog, which causes damage on environmental. However, due to the high thermal efficiency and low carbon dioxide emission, the usage of a diesel engine is prevailed. In this study, the DC non-thermal plasma technology used to the particulate matter (PM) aftertreatment. The exhaust gas characteristics and energy density were investigated on the dynamometer test bed and chassis dynamometer with CVS-75 mode in a passenger diesel car. It was reported that the smoke removal efficiency has around the 70% in the dynamometer test with 80W energy consumption and the PM removal efficiency has the 68% in the real car test. The NOx also reduced the 20% according to electrode type respectively. Considering these results, plasma technology is one of the ways to simultaneously removing method the particulate matter (PM) and NOx.