• Title/Summary/Keyword: PEGs

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Synthesis and Characterization of Poly(ethylene oxide) Derivatives Containing Carbonate Linkages (고분자 주사슬에 카보네이트 관능기가 도입된 새로운 폴리에틸렌 옥사이드 유도체의 합성 및 분석)

  • 최유선;차국찬;서정인;정동준;안정호
    • Polymer(Korea)
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    • v.25 no.6
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    • pp.759-764
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    • 2001
  • In order to obtain PEO with reduced crystallinity, novel PEO derivatives containing carbonate linkages in the main chain have been synthesized by the reaction of various molecular weight poly (ethylene glycol)s (PEGs) with dimethyl carbonate (DMC) in the presence of $H_2SO_4$ to yield methyl carbonate terminated PEGs, followed by condensation reaction under vacuum in the presence of titanium isopropoxide (TiP) catalyst. The number average molecular weight of PEGs used was in the range of 200 and 600 g/mol. The structure and compositions of the resulting polymers were characterized by $^1$H-NMR and $^{13}C-NMR$. Their thermal behavior and molecular weight were characterized by DSC/TGA and GPC, respectively.

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Uplift Bearing Capacity of Spiral Steel Peg for the Single Span Greenhouse (온실용 나선철항의 인발저항력 검토)

  • Lee, Bong Guk;Yun, Sung Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yu, Chan;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.23 no.2
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    • pp.109-115
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    • 2014
  • This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.

Development of Biosphere Assessment Modeling Strategy for Deep Geological Disposal in Generic Site of the Korean Peninsula

  • Do Hyun Kim;Wontak Lee;Dongki Kim;Jonghyun Kim;Joowan Park
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.21 no.1
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    • pp.149-164
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    • 2023
  • As part of the safety case development for generic disposal sites in Korea, it is necessary to develop generic assessment models using various geosphere-biosphere interfaces (GBIs) and potentially exposed groups (PEGs) that reflect the natural environmental characteristics and the lifestyles of people in Korea. In this study, a unique modeling strategy was developed to systematically construct and select Korean generic biosphere assessment models. The strategy includes three process steps (combination, screening, and experts' scoring) for the biosphere system conditions. First, various conditions, such as climate, topography, GBIs, and PEGs, were combined in the biosphere system. Second, the combined calculation cases were configured into interrelation matrices to screen out some calculation cases that were highly unlikely or less significant in terms of the exposure dose. Finally, the selected calculation cases were prioritized based on expert judgment by scoring the knowledge, probability, and importance. The results of this study can be implemented in the development of biosphere assessment models for Korean generic sites. It is believed that this systematic methodology for selecting the candidate calculation cases can contribute to increasing the confidence of future site-specific biosphere assessment models.

The Effect of Group Motor Activity Program on Motor Function and Self-efficacy of Children in the Community Children's Center (집단 운동 활동 프로그램이 지역아동센터 아동의 운동기능 및 자기효능감에 미치는 영향)

  • Kim, Hye Jin;Je, Young Hyeon;Seo, Jeong Min;Kim, Eun Young
    • The Journal of Korean Academy of Sensory Integration
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    • v.18 no.1
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    • pp.23-33
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    • 2020
  • Objective : The current study investigated the effectiveness of group motor activity programs on motor function and perceived self-efficacy of children in the community children's center. Methods : Nine children aged six to nine years participated in this study. We applied the group motor activity program for 7 sessions. Before and after the intervention, children's motor function and self-efficacy were assessed using the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition, Short Form (BOT-2 SF) and the Perceived Efficacy and Goal Setting, Second Edition (PEGS-2), respectively. Results : The group motor activity program enhanced the motor function and self-efficacy of children. Conclusion : This study showed that the group motor activity program was effective for increasing the objective motor function and the subjective self-efficacy of children in the children's community centers. The result suggests that programs using activities in the community centers can facilitate children's self-development.

Structure of sensilla on the Antenna and Mouthparts of the Oriental Tobacco Budworm(Heliothis assulta Guenee) Larvae (담배나방의 유충의 촉각 및 구기 감각기의 구조)

  • 박순식;부경생
    • Korean journal of applied entomology
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    • v.27 no.2
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    • pp.94-102
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    • 1988
  • Studies were carried out to describe the structure and distribution of various sensilla on the antenna and mouthparts of the Oriental tobacco bud worm (H. assulta) larvae by light and scanning electron microscopy. The larval antenna has 3 segments. The second segment has 2 hairs and 3 pegs, while the third segment shows 3 regular pegs and a segmented peg (styloconicum type). Each mandible bears 2 aporous hairs on the lateral surface. The labrum bears 12 aporous hairs on its external surface. and 6 aporous hairs, 4 coeloconica-like sensilla and 2 campaniformia-like sensilla on its epipharynx. The stipes has 3 hairs, and the galea has 3 pegs. 2 papillae and 2 domes. The maxillary palpus has only a digitiform sensillum on its 1st segment but 11 sensilla of 4 different types on its 2nd segment. Maxillary sensilla represent almost 70% of total number of larval sensilla on the mouthparts. Labial pal pus has a single segment bearing a large segmented uniporous peg and a small peg. Finally their possible fun¬ctions were suggested.

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Microbial Degradation of Polyethylene Glycol (Polyethylene Glycol의 미생물학적 분해)

  • 이종근;이상준;이재동;박송희;박재림
    • Korean Journal of Microbiology
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    • v.24 no.3
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    • pp.329-334
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    • 1986
  • The bacteria capable of utilizing polyethylene glycol(PEG) 6,000 as a sole carbon source were isolated from soil and sewage water connected to factory area. The isolate designated as EL-033 had high biodegradability on PEG 6,000, and was identified as Micrococcus sp. Micrococcus sp. EL-033 could grow on and degrade di-, tri-, tetraethylene glycols and PEGs with molecular weight up to 6,000 and very slowly stilize PEG 20,000 as sole carbon source, but not degrade ethylene glycol. The growth rate of isolate was increased in the higher molecular weight PEGs. The optical culture medium was established to be as follow: PEG 6,000, 0.2%(w/v); $K_2HPO_4$, 0.1%; $NaH_2PO_4{\cdot}12H_2O,\;0.1%\;:\;MgSO_4{\cdot}7H_2O$, 0.05%; polypeptone, 0.1% in distilled water, pH7.5. About 90% of PEG 6,000 was degraded in exponential phase of 48h culture and PEG 6,000 was completely degraded during 72h.

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Study on How the Height of the Table Influences of the Functional Ability Perfomence to Patients Group with Stroke (뇌졸중 환자군을 대상으로 한 작업대 높이가 수행도에 미치는 영향에 대한 연구)

  • Yu, Young-Yul;Kim, Hee-Soo
    • Journal of the Ergonomics Society of Korea
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    • v.28 no.4
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    • pp.9-15
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    • 2009
  • Our study goal is to find out how the table height influences functional ability of upper extremity to patients with stroke when they are having therapy. In this study, we tested forty patients with stroke at the age of over sixty-five who do not have visual, auditory disability and have no difficulty in communicating and moving things by using upper extremity. And they were able to pinch grip in hospital. We used occupational table for occupational therapy as Lab Materials. We also used cube and pegs board to test upper extremity functional ability. We used occupational table for occupational therapy as Lab Materials and we used cube and pegs board to test upper extremity functional ability. The method is that we measured the recommended table height that takes the subjects' size into consideration and patients' preferred table height and therapists' preferred table height and we applied them and then we have done a comparative analysis and set significance level(p<0.05). As the result, we found the Statistically significant between the recommended height and the other two, which are patients' preferred height and therapists' preferred height. We also discovered that functional ability of upper extremity varies significantly depending on each table height. We came to a conclusion that the table height had effects on the upper extremity functional ability of patients with stroke who are over sixty-five years old. It is therefore considered that the proper table height is important to improve upper extremity functional ability of patients with stroke for their physical therapy.

Development of Threshing Cylinder for Reduction of Soybean Seed Damage (콩 탈곡손상 절감을 위한 콩 탈곡통 개발)

  • Cho, Yong-Jin;Lee, Kyou-Seung
    • Journal of Biosystems Engineering
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    • v.35 no.6
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    • pp.380-386
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    • 2010
  • This study was carried out to develop soybean thresher which is able to reduce the soybean threshing damage in comparison to the conventional thresher. A threshing cylinder with different diameter of 480 and 384 mm at each end and with one quarter disc pegs of 60 mm radius was developed and attached to the prototype thresher. A conventional thresher which has a threshing cylinder with $\wedge$ type threshing pegs and same diameter of 480 mm at each end was used for comparative test. A series of comparative performance test was conducted using sun-yu and chung-ja soybean. For sun-yu bean, which is white and usually used for soybean paste and soy sauce, the ratio of damaged beans of prototype ranged 2-3% for 330-360 rpm which is recommended cylinder speed by manufacturer. The ratio of damaged beans of conventional thresher was 3-4% for the same range of cylinder speed. chung-ja beans with black color usually shows high damaged ratio compared with white beans, thus cylinder speed of 250-300 rpm is recommended by manufacturer to reduce the damaged ratio. For this range of cylinder speed, the damaged ratio of prototype was 1.3-1.4% and it was 2.7-6.1% for the conventional thresher. Thus prototype is able to reduce the damaged ratio 1.5-5.0% compared with conventional thresher. Prototype shows 0.4% of unthreshed soybean ratio for sun-yu bean in the optimum range of cylinder speed and it was 0.87% for the conventional thresher. For chung-ja bean, the ratio of unthreshed soybean was almost same for both prototype and conventional thresher with the value of 4.0%. The reason of high unthreshed soybean ratio for chung-ja bean compared sun-yu bean is due to the high seed moisture content of 29.11% which is much higher than that of the recommended.

The Effects of Agricultural Experience Program on Agricultural Literacy and Hand Function Improvement of Adolescents Living in Self-reliance Residence Hall

  • Ryu, Ja Yeong;Kim, Mi Jin;Yun, Suk Young
    • Journal of People, Plants, and Environment
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    • v.24 no.3
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    • pp.277-283
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    • 2021
  • Background and objective: This study was conducted to increase understanding of agriculture through agricultural experience programs for adolescents living in self-reliance residence hall, and to investigate changes in work performance ability through changes in hand function. Methods: There were 11 subjects, and the average age was 18.2 years, all males without disabilities. The agricultural experience program consists of a total of 10 sessions including orientation and watching videos on future agriculture, creating vegetable gardens, planting, managing each crop, harvesting, visiting the processing room, and selling at a local food store. Results: The change in agricultural literacy by the agricultural experience program positively improved from a score of 113.73 to 127.91 (p = .008). The changes by sub-item are as follows. The value and safety of agri-foods (p = .020) and agriculture and natural environment (p = .007) were significantly improved. The function and value of rural areas (p = .050), production of agricultural products (p = .160), processing and distribution of agricultural products (p = .248), and agricultural policies (p = .058) were not significantly changed. The simple function of the hands was measured by the number of pegs inserted during 30 seconds, and the assembly function was measured by the number of pegs inserted during 60 seconds. In the case of simple function, the dominant hand was improved from 14.82 to 15.83 (p = .014), andthe non-dominant hand was also significantly improved from 13.79 to 15.01 (p = .002). There was no significant improvement in the simple function (p = .153) and assembly function (p = .770) of both hands. Conclusion: It is considered that the agricultural experience program will enable youths living in self-reliance residence halls to enhance their understanding of agriculture as an occupation, and enable them to play a role as wise consumers by positively affecting improvements in their agricultural literacy and simple hand functions.

Empirical Analysis of Minimum Query Strategies in Mastermind Game using Black Pegs Only (검정 핀 만을 이용한 마스터마인드 게임 최소 질의 전략의 실험적 분석)

  • Lee, Jong-Hyun;Ahn, Chang-Wook
    • Proceedings of the Korean Information Science Society Conference
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    • 2012.06a
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    • pp.414-416
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    • 2012
  • 마스터마인드는 한 플레이어가 정한 비밀 코드를 다른 한 플레이어가 질의를 통해 추리해내는 방식으로 진행되는 암호해독 게임으로서 연구 초기 단계에 D. Knuth에 의해 암호해독자가 언제나 질의 5회 이내에 비밀코드를 찾을 수 있음을 보였고, 그 후 연구자들에 의해 변형된 형태의 마스터마인드 게임의 최소 질의 수가 연구되어 왔다. 본 논문에서는 마스터마인드 문제해결을 위한 전략들을 제안하고 시뮬레이션을 이용한 실험적 분석방법을 제시한다.