• Journal of the korean Society of Automotive Engineers
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• v.9 no.2
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• pp.1-4
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• 1987

내연기관 연구에 전념하는 모든 사람들의 한결같은 3대 염원은 연비향상, 비출력증대 및 유해 배기가스 성분 감소이다. 이중 비과급 가솔린 기관의 경우 비출력 증대를 위한 4-stroke cycle 엔진에서의 여구는 현지까지 헤아릴 수 없이 많은 연구가 진행되어 발전의 한계에 도달한 느낌 이다. 따라서 이의 실질적인 증대는 시각을 달리하여 2-stroke cycle로의 전환으로서만 가능하리 라 본다. 2-stroke 엔진은 원래 이목적으로 고안된 것이라는 것은 주지의 사실이다. 그러나 이 장치가 비출력면에서 효과적인 가솔린엔진의 경우에서도 현재까지 별로 각광을 받지 못한 것은 다음과 같은 몇가지 두드러진 이유 때문이라고 본다. 첫째 흡입연료의 일부가 소기(scavenging) 과정에서 배기공으로 곧바로 유출됨으로 배기 공해성분을 증가시키고 연료손실에 따른 연비저감 을 초래하는 것이다. 둘째로 crankcase 소기를 이용하는 소형가솔린 2-stroke 엔진에서는 새 공 기의 흡입이 충분치 못하여 일방적으로 높지 않은 소기효율을 고려한 최종 흡입 체적효율은 상당 히 낮아지게 됨으로써 목적하는바의 비출력 증대의 득을 별로 얻지 못함은 물론 잔류가스율이 높아 저부하, 저속도에서 엔진의 구동이 손조롭지 못ㅎ하고 시동이 어려워지는 특성을 나타나게 된다. 따라서 이러한 바람직하지 못한 결과를 감수할 수 있는 경우에는 소형원동기에 주로 2-stroke 가솔린 엔진이 이용되어 왔다. 요사이 이러한 약점들을 타개할 수 있는 고안들이 미국 SAE지에 소개되어 관심을 끌고 있어 이에 대해 요저먹으로 소개하고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.26-31
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• 2011

In this study, it made to run conventional single direct injection(DI) diesel engine, which adapted bulk combustion system not following spark ignition system without any ignition apparatus. It was heated and controlled inlet-air into conventional single DI diesel engine. The maximum value of brake thermal efficiency was at 35 region of air-fuel ratio. On the contrary, when the region of air-fuel ratio leaner than 35, brake thermal efficiency was decreased suddenly. And brake thermal efficiency was increased as much as inlet-air heating temperature increased. So, when air-fuel ratio was decreased and inlet-air heating temperature was higher, the engine was in optimal operation condition.

• International Area Studies Review
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• v.15 no.3
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• pp.29-53
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• 2011

This paper studies the contribution of imports and inward foreign direct investment (FDI) as a vehicle of technology transfer onto the EU new member states at both macroeconomic and industry level. The paper takes the effectiveness of the recipient's utilization into account by constructing a new index, the so-called Effective Absorption (EA) Index, to measure ability to absorb and utilize the foreign technology in the recipient country. Using data from 12 donors and 10 recipients from 1998 to 2009, the study at macroeconomic level indicates that technical spillovers of foreign research and development (R&D) play more crucial role relatively to domestic R&D on total factor productivity (TFP) growth of the new member states. Imports are found as the major vehicle of technical spillovers rather than inward FDI. The study at industry level is conducted by using data from 17 manufacturing industries of 10 donors and 6 recipients during 1998 to 2009. The empirical results also support the findings at country level. The patterns of technology transfer are different across industries. Nonetheless, technical spillovers exhibit significantly high contribution on TFP growth in high-tech manufacturing industries.

• Fire Science and Engineering
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• v.27 no.3
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• pp.30-37
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• 2013

The ultimate purpose of the present study is to secure a effective method for foam liquid discharge when the mixing ratio deviates from the permissible range due to a decrease in the bypass flow rate resulting from a decrease in the cross sectional area of the foam liquid piping ranging from the branching header of one foam proportioner to the branching headers of multiple branching foam fire-extinguishing systems in the region for fire extinguishing and then to the standpipe at the lower part of the storage tank when a fire occurred in a combustible tank. To this end, the cause of mixing ratio variations following changes in the flow rates of existing foam fire extinguishing systems was analyzed, methods for compensation for constant mixing ratios were investigated, and it was proved that metering orifice replacements that could expand the cross sectional area of the stock solution inhaling piping was the most effective way for the improvement of form fire extinguishing systems' mixing ratios through foam proportioner venturi, foam chamber orifice, and metering orifice replacement experiments.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.170-177
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• 2011

As the Internet market develops and grows, the Internet advertising has emerged as a critical medium of advertisement and become important in a modern society. In addition, the Internet advertising is more fascinating and attractive than other media in terms of diversity and absorption. In the Internet banner advertising, for example, various expression methods which attract attention from users have been more than just visual advertisement, arousing curiosity and interest. Especially, humorous expressions in the Internet banner advertising have brought a new paradigm to advertising market. Therefore, this paper has investigated the patterns of humorous expressions in banner advertising and analyzed the related case studies to make a contribution to the effective production of the Internet banner advertising, which induces user awareness and selection. For this, it has been attempted to analyze humorous patterns and involvement that are found in humorous banner advertisings such as CIA Athletica, Panadol, Toy & Stok, Adidas and Lipton among the banners which have relatively high preference in Banner blogs.

• Journal of Hospice and Palliative Care
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• v.14 no.1
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• pp.8-19
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• 2011

Purpose: This study identifies research trends and provides fundamental data related to curative power of aromatherapy to relieve pain in Korea. Methods: The study analyzed 44 experimental studies on humans that were published in Korea before the end of December, 2009. The key words used for searching were: aroma, aromatherapy, hyang-yobeob, hyanggi-yobeob, hyanggichilyo, aromatherapy and pain, headache, scapulodynia, omodynia, feeling uncomfortable in the perineal region, sense of pain, labor pains, arm pain, menstrual pain, aches, and dysmenorrheal. Those words were found on websites, including those for Korea Education & Research Information Service, the National Assembly Library, KISS, KoreaMed, and NDSL. Collected data were analyzed using descriptive statistics. Results: The results showed that most of essential oils to relieve pain is composed of three to four kinds of oils, including Lavender, Roman chamomile, Rosemary, and Clarysage. Aromatherapy is applied usually by means of massage (50%), inhalation (13.6%), or a combination of the above two (13.6%). Measuring instruments as a dependent variable include VAS, questionnaire, GRS, blood pressure, pulse, and Algometer. Aromatherapy plays an important role in soothing headaches and arthralgia. However, when it comes to labor and menstrual pain, it doesn't seem to be effective. Conclusion: The study found that different kinds of oil, frequencies, and periods of time are used for the same symptoms. Further research should employ standardized oil blending, application, duration, and measuring instruments, and more systematically analyze the effects of aromatherapy to establish the effects on relieving pain.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.393-397
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• 2012

This study developed a rapid egg-salting method using a temperature change in NaCl solution under pressure. The permeation effects(PEs) of NaCl into eggs at ambient pressure were analyzed 1) after soaking them in 20, 30, or 40%(w/v) NaCl solution at $50^{\circ}C$ and 2) after soaking in 20~40% concentrations(w/v) of NaCl solution at $4^{\circ}C$ immediately after soaking at $50^{\circ}C$ for 1 hr(temperature change method; TCM). Under permeation conditions(40% NaCl solution with TCM), the PE of NaCl into eggs at various pressures(4.0~7.0 MPa) was determined. The PE improved with increasing NaCl concentration and pressure. In 40%(w/v) NaCl solution, the PE was more rapid with TCM(0.70% for 2 hr) than without TCM(0.60% for 2 hr). At 7.0 MPa pressure, the PE was more rapid with TCM(1.66% for 15 min) than without TCM(1.40% for 15 min). These results suggest that the TCM-induced contraction of the egg membrane improved the PE. Therefore, we believe that the development of a rapid salting method for seasoning eggs is possible with the TCM.

• The korean journal of orthodontics
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• v.29 no.5 s.76
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• pp.551-562
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• 1999

This study was undertaken to investigate the relation between orthodontic force magnitude and the amount of tooth movement. And more light force application for reducing root resorption Twenty-four rats were divided into three experimental groups(A, B, C) based on force magnitude and application method. Springs of 50g force were applied to A group, springs of 100g force were applied to B group and springs of 25g force were applied to C group initially, and after 4 days springs of C group were changed to springs of 50g force. Two kinds of $sentally^{(R)}$(GAC U.S.A.) closed coil spring, 50g and 100g, were used. And we made 25g springs by heat treatment process of 50g springs. Each spring was inserted between the maxillary central incisor and the maxillary left first molar. Amounts of tooth movement were measured everyday by digital caliper($Digimatic^{(R)}$, Mitutoyo, Japan) under inhalation anesthesia for 15 days. After 15 days, all rats were sacrificed and histological samples were obtained with Hematoxyline-Eosin stain and Masson's trichrome stain. Following conclusion were made; 1. Group B showed the mean cumulative tooth movement of $2.19{\pm}0.41mm$ at 15th day, which was greatest among three groups, followed by group C($2.06{\pm}0.10mm$), group A($1.90{\pm}0.49mm$) respectively. however, there was no statistically difference among three groups. 2. All groups showed general tooth movement pattern and A, B, C group finished lag phase at 9th, 8th, 7th day, but there was no statistical significance. 3. Group A,B,C showed root resorption and especially group B showed the most severe root resorption and group C showed milder root resorption than other groups. According to the above results, large initial force with the development of a flirty widespread hyalinized zone may cause severe root resorption, so initial force should be applied lightly to reduce hyalinized area and eventually root resorption and then increased force will induce efficient tooth movement.

• Development and Reproduction
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• v.2 no.2
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• pp.213-221
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• 1998

Intracytoplasmic sperm injection (ICSI) has been widely used to treat couples with infertility due to severely impaired sperm charateristics and for whom conventional in-vitro fertilization (IVF) had failed. The extent to which the morphology of the oocyte at the light microscopy level is related to the results of ICSI vis controversial. In this study, oocytes from 44 patients were reviewed. The ICSI procedure was recorded through CCD camera. The oocytes were divided into five groups according to the presence of cytoplasmic inclusions, the width of perivitelline space (PVS), the presence of cell debris in PVS, the status of first polar body and the flexibility of oolemma. The results showed that the fertilization rate and embryonic development were not associated with the morphological criteria of oocyte. The degeneraton rate of oocytes after ICSI was significantly higher (P<0.001) in the oocytes whose membranes were broken at the moment of insertion (17.7%) than the oocytes whose membranes were broken by aspiration of cytoplasm (1.6%). More oocytes with cytoplasmic inclusions (48.4% vs. 25.1%, p<0.001), wide PVS (35.2% vs. 19.0%, p<0.001), or cell debris in PVS (53.3% vs. 38.4%, p<0.05) were observed in patients with female factor infertility compared to patients with male factor infertility. These results .suggest that the fertilization rate and embryonic development after ICSI are not correlated with oocyte morphology based on the presence of cytoplasmic inclusions, size of PVS, the presence of cell debris in PVS and the status of polar body. And the degeneration rate of oocytes after ICSI was associated with the flexibility of oolemma.