• Korean journal of applied entomology
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• v.41 no.4
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• pp.239-245
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• 2002

It was investigated whether or not such helpers as worker bee, bee-cocoon and egg-cup etc, have any effects on oviposition and colony foundation of the bumblebee queen, Bombus ignitus. Among the helpers tested, the callow workers of B. ignitus and B. terrestris showed the most remarkable effects on the oviposition rates to 92% and 88%, respectively. The live cocoon as a helper improved oviposition rate over 60%. A narcotized old worker 10-20 days-aged after emergence, showed similar effects to a callow worker on the colony development such as oviposition rate, colony foundation and progeny-queen production. On the other hand, dried cocoon, callow honeybee worker or egg-cup did not show a positive effect as a helper. In the number of workers recruited to a foundation queen, two workers showed better effect than one worker on the colony development, with no difference between two and more.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.11a
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• pp.88-88
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• 2001

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2001.10a
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• pp.80-80
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• 2001

• Polymer(Korea)
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• v.27 no.4
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• pp.313-322
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• 2003

The morphology of poly(ethylene terephthalate) (PET)/poly(m-xylene adipamide) (MXD-6) blends, which was prepared by adding compatibilizer and interchange reaction agent, was investigated. The morphological change in the stretched blend films was also studied. The stretched film showed a dispersed MXD-6 fibril. This fibril became finer with increasing draw ratio (DR). The addition of compatibilizer and interchange reaction agent had no effect on the improvement of interfacial adhesion but caused a defect between the continuous phase and the dispersed phase, leading to the formation of irregular fibril. The change in the superstructure of blends with composition and draw ratio was examined with light scattering (LS). The H$\sub$v/ LS patterns showed a double-cross type pattern consisting of a broad rod-like pattern and a sharp cross streak. On the basis of the model calculation of the H$\sub$v/ pattern, it was found that the appearance of the double-cross type pattern was attributed to the stacking of crystals oriented along the draw direction. The crystals were gradually oriented to the stretching direction with draw ratio. As a result, the high level of orientation was obtained fur the sample of draw ratio is 6.0.

• Solar Energy
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• v.15 no.3
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• pp.141-149
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• 1995

The tungsten oxide thin films were prepared on $s_i$ wafer by using an electron-beam evaporation technique. Thickness and structure of tungsten oxide film degraded in various electrolytes were analyzed by Rutherford backscattering spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscope. Thickness of $WO_3$ film was the most dissolved in 1M $H_2SO_4$ electrolytye. We have confirmed that the degradation of this films was accelerated by $H_2O$ in electrolytes. But the electronic structure of film degraded by electrolyte contained of glycerol was not changed as comparision with as-deposited film. The degradation may be attributed to a change of thickness and the surface morphology of the film.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.344-350
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• 2003

In this paper, we propose a novel sharing method ordering the events occurring between users collaborated with the common telecomputing environment. We realize the sharing method with multimedia data to improve the coworking effect using teleprocessing network. This sharing method advances the efficiency of communicating projects such as remote education, tele-conference, and co-authoring of multimedia contents by offering conveniences of presentation, group authoring, common management, and transient event productions of the users. As for the conventional sharing white board system, all the multimedia contents segments should be authored by the exclusive program, and we cannot use any existing contents or program. Moreover we suffer from the problem that ordering error occurs in the teleprocessing operation because we do not have any line-up technology for the input ordering of commands. Therefore we develop a method of retrieving input and output events from the windows system and the message hooking technology which transmits between programs in the operating system In addition, we realize the allocation technology of the processing results for all sharing users of the distributed computing environment without any error. Our sharing technology should contribute to improve the face-to-face coworking efficiency for multimedia contents authoring, common blackboard system in the area of remote educations, and presentation display in visual conference.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.62-62
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• 2000

도공지 제조 시 적절한 표면특성을 지닌 원지를 사용하는 것은 최종 도공지 품질향상은 물론 조업성 개선에도 필수적인 요소이다. 이러한 목적을 달성하기 위해 도공원지의 표면 사이징이 실시되고 있다. 도공원지의 표면 사이정 시 양성전분을 이용할 경우 서로 반대로 하전된 전분 과 섬유 사이에 발현되는 정전기적 인력에 의해서 표면 사이정 전분의 원지로의 전분 침투가 억제되어 도공원지의 불투명도, 광택도 인쇄적성 둥의 물성 향상을 꾀할 수 있다. 또 이러한 원지를 이용하여 도공을 할 경우 음전하를 띤 도공액 구성성분과 양전하를 띤 원지 표면의 정 전기적 작용에 의해 도공액의 부동화가 촉진될 수 있으므로 도공액의 표면 잔류성이 향상되 며, 도공층 공극 구조 개선에 따른 광학적인 성질의 개선도 기대할 수 있을 것으로 기대된다. 본 연구에서는 양성전분으로 표면 사이정 된 원지를 사용한 도공지와 기존의 산화전분을 이용하여 표면 사이정한 원지를 이용하여 제조된 도공지의 특성을 비교하였다. 또 양성전분에 의한 표면 사이징 효과를 보다 극대화하고 도공안료와 원지 표면과의 반응성을 증가시키기 위 해 양이온성 폴리머를 표면 사이정 시 첨가하여 표면 사이칭을 하는 방법을 평가하였다. 아울 러 양성전분과 도공안료와의 반응에 따라 도공층의 부동화가 촉진될 수 있다는 근거를 구명하 기 위해 레올로지적인 접근을 시도하였으며, 도공층의 공극 특성 관찰, 광산란 및 광홉수 계수 측정 등을 통해 양성전분으로 표면 사이정된 도공층의 구조적 특성을 분석하였다. 그 결과 산화전분에 비해 양성전분으로 표면 사이징한 원지의 경우 도공지의 불투명도가 높게 나타났다. 이는 양성전분으로 표면 사이정한 원지를 사용한 경우 도공층의 구조가 광 산란계수를 향상시킬 수 있도록 변화되었기 때문임을 확인하였다. 표면 사이징시 양이온성 폴리머를 첨가할 경우 불투명도 개선에 상당한 효과가 있었으며, 전분 대비 1% 이하의 첨 가량에서도 어느 정도의 개선이 가능하였다. 양성전분에 의한 도공액의 조기 부동화가 발현 된다는 것을 구명하기 위해서 도공액의 점탄성적 평가를 실시한 결과 산화전분에 비해 양성 전분 상에서 도공액의 storage modulus가 높고 critical strain point 역시 높은 값을 나타낸 다는 것을 확인하였다. 이는 양성전분과 도공액, 특히 클레이와의 정전기적 인력에 의한 반 응 결과로 생각된다. 양성전분을 이용한 도공원지의 표면 사이정 기술은 특히 평량이 낮은 도공지의 경우 수분 의 침투를 억제함으로써 도공공정에서의 지절을 감소시킬 뿐 아니라 불투명도 등 광학적 성질 을 개선시키고, 표면 커버리지를 향상시키는 효과를 나타낼 것으로 기대된다.

• Korean Journal of Poultry Science
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• v.43 no.1
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• pp.47-54
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• 2016

The aim of this study was to investigate the expression patterns of key genes involved in lipid metabolism in response to dietary Coenzyme Q10 (CoQ10) in hens. A total of 36 forty week-old Lohmann Brown were randomly allocated into 3 groups consisting of 4 replicates of 3 birds. Laying hens were subjected to one of following treatments: Control (BD, basal diet), T1 (BD+ CoQ10 100 mg/kg diet) and T2 (BD+ micellar of CoQ10 100 mg/kg diet). Birds were fed ad libitum a basal diet or the basal diet supplemented with CoQ10 for 5 weeks. Total RNA was extracted from the liver for quantitative RT-PCR. The mRNA levels of HMG-CoA reductase(HMGCR) and sterol regulatory element-binding proteins(SREBP)2 were decreased more than 30~50% in the liver of birds fed a basal diet supplemented with CoQ10 (p<0.05). These findings suggest that dietary CoQ10 can reduce cholesterol levels by the suppression of the hepatic HMGCR and SREBP2 genes. The gene expressions of liver X receptor (LXR) and SREBP1 were down regulated due to the addition of CoQ10 to the feed (p<0.05). The homeostasis of cholesterol can be regulated by LXR and SREBP1 in cholesterol-low-conditions. The supplement of CoQ10 caused a decreased expression of lipid metabolism-related genes including $PPAR{\gamma}$, XBP1, FASN, and GLUTs in the liver of birds (p<0.05). These data suggest that CoQ10 might be used as a dietary supplement to reduce cholesterol levels and to regulate lipid homeostasis in laying hens.