• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.1240-1246
• /
• 2006

Generally, there are two types of main factors to affect output power quality of a auxiliary power supply an EMU(electric multiple unit). One is a voltage flicker by amplitude modulation of short time and air compressors. The other is repetitive motion of large capacity motor such as air compressors, HVAC unit etc. in main factors. This paper compared two kinds of fluorescent lamp, 32W (after remodeling interior) and 40W(before remodeling interior) and measured the light output varying input power(AC220V) for a flicker phenomenon related power supply of lamps in EMU. Also, we analyzed a flicker considering EMU operating time and density in order to grasp main factors of a load change to cause a voltage change. As a results of test, a 40W fluorescent lamp was more insensitive with 20.26% degree an eye recognition degree sides about changes of the input power and lower with 19.9% voltage side generating flicker compare with fluorescent lamp 32W. Also, we confirmed the fact which the fluorescent lamp flicker was generated by varying fluorescent lamp output voltage when the commercial EMU was in high driving density and at the busy time. Additionally, we confirmed the frequency band which an EMU passenger could feel sensitively blinking of a fluorescent lamp was visually $8Hz{\sim}15Hz$.

• Restorative Dentistry and Endodontics
• /
• v.24 no.1
• /
• pp.187-199
• /
• 1999

Bone remodeling is characterized by the continuing processes of osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Bone metabolism is tightly regulated at the local level by networks of hormones, cytokines, and other factors. In pathological conditions of bone remodeling, including osteoporosis and periodontal diseases, inflammatory cytokines and local mediators are responsible for enhancement of osteoclast resorption and inhibition of repair at the sites of bone resorption. TNF-${\alpha}$ is a pleiotropic hormone with actions on the differentiation, growth, and functional activities of normal and malignant cells from numerous tissues. TNF-${\alpha}$ has been proposed as a local mediator of the control of bone turnover in situations of chronic inflammation, and it has been assumed that the local source of TNF-${\alpha}$ is the monocyte in the adjacent bone marrow or the local circulation. TNF-${\alpha}$ is a potent inducer of bone resorption. TNF-${\alpha}$ is known to induce the activation of apoptotic signaling pathway, which leads to the apoptosis of bone cells. We demonstrated that treatment of murine osteoblastic MC3T3E1 cells with TNF-${\alpha}$ decreases proliferation as well as alkaline phosphatase (ALP) activity in a dose depenent manner. In addition, TNF-${\alpha}$ increases osteoclast-like cell formation in $1{\alpha}$, 25(OH)2D3 or PGE2-treated bone marrow cell culture. When cells were cultured in TNF-${\alpha}$ free ${\alpha}$-MEM, this inhibitory effect of ALP activity was reversible up to 10 ng/ml TNF-${\alpha}$, in contrast, at the 20 ng/ml TNF-${\alpha}$, irreversible. In this concentration, TNF-${\alpha}$ may induce apoptosis in MC3T3E1 cells. In this study, TNF-${\alpha}$ induces apoptosis resulting in chromosomal DNA fragmentation, preceded by JNK/SAPKs and caspase-3 activation. Our present results show that JNK/SAPKs and caspase-3 are activated by TNF-${\alpha}$, suggesting that the JNK/SAPKs and caspase-3 participate in the bone resorption, associated with apoptosis.

• International Commerce and Information Review
• /
• v.11 no.2
• /
• pp.173-201
• /
• 2009

As a result of overemphasizing the goods sector in trade structure, Korea does not meet properly the global trend which has the key role of 'trade in services' as the service economy have been expanded. Hereafter, it is easily forecasted that trade in services will be one of the main factors for Korea's competitiveness and engine of growth. Nevertheless, because Korea does not equip the concreteness of governance for trade in services, it is possible that the efficiency deterioration of trade volume, confusion of Korea's trade policy, conflict among trading countries, and discordance between the interested parties may be occurred. This paper analyzes the governance system of Korea for trade in services in order to enhance the competitiveness reflecting the importance of trade in services and to draw some strategies for remodeling the service governance system. It is expected to raise the efficiency of Korea's trade policy by constructing the systematic governance for trade in services, and to remove lots of latent risks during global transactions by improving the imbalance between manufacturing and service part for the development of trade in services in Korea. Analysis revealed itself the result that Korea is weak enough to can not identify the governance system about trade in services. Except 'Extent of Services' article of the Foreign Trade Act, Korea has not prepared the governance system for trade in services so that governance system have been scattered overly or decentralized. Problems about trade in services are not limited to enterprise's side, but extended to all the players including government agency whole, academic world and research institute. Therefore, the governance of trade in services should be strengthened and systematized by making the model law for trade in services(provisional name : Master Law for Trade in Services or Promotion Law for Trade in Services) by formatting type of fundamental law or separate legislation. If the bill legislation does not meet the conditions, the Foreign Trade Act should be totally reformed to Omnibus Trade Act concept including trade in services.

• Journal of Chest Surgery
• /
• v.48 no.4
• /
• pp.238-245
• /
• 2015

Background: Some patients show favorable changes in the descending aortic false lumen after conventional repair of acute type A dissection, although the incidence of favorable changes has been reported to be low. We aimed to investigate the incidence of positive postoperative changes in the false lumen and the factors associated with positive outcomes. Methods: In 63 patients who underwent surgery for type A acute dissection as well as serial computed tomography (CT) scanning, morphological parameters were compared between the preoperative, early postoperative (mean interval, 5.4 days), and late CT scans (mean interval, 31.0 months) at three levels of the descending thoracic aorta. Results: In the early postoperative CT images, complete false lumen thrombosis and/or true lumen expansion at the proximal descending aorta was observed in 46% of the patients. In the late images, complete thrombosis or resolution of the proximal descending false lumen occurred in 42.9% of the patients. Multivariate analysis found that juxta-anastomotic false lumen thrombosis was predictive of favorable early changes, which were in turn predictive of continuing later improvement. Conclusion: Even after conventional repair without inserting a frozen elephant trunk, the proximal descending aortic false lumen showed positive remodeling in a substantial number of patients. We believe that the long-term prognosis of type A dissection can be improved by refining surgical technique, and particularly by avoiding large intimal tears at the anastomosis site during the initial repair.

• Journal of the Korean earth science society
• /
• v.30 no.1
• /
• pp.96-110
• /
• 2009

The ESE (Earth Systems Education) teaching module was developed to teach an "Earth and Star" unit for the 8th grade (aged 14) students. The planet remodeling activity was developed as a sub-ESE teaching module. The main point of this activity was that students were supposed to remodel planets for life to live on. The purpose of this study was to visualize students' thought and to interpret their understandings through their drawings and writings. A framework of analysis with four categories was designed and applied to analyze students' cognitive structure. In order to explore students' cognitive contents, the analyzing factors were classified into two domains: subsystems of the earth systems and use of science & technology. Results revealed via the planet remodeling activity that students' cognitive characteristics were impacted by ESE activities such as Earth literacy.

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.3
• /
• pp.291-297
• /
• 2015

An oral environment is constantly exposed to environmental factors and microorganisms. The periodontal ligament (PDL) fibroblasts within this environment are subject to bacterial infection and allergic reaction. However, how these condition affect PDL fibroblasts has yet to be elucidated. PDL fibroblasts were isolated from healthy donors. We examined using reverse transcription-polymerase chain reaction and measuring the intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$). This study investigated the receptors activated by exogenous bacterial pathogens (Lipopolysaccharide and peptidoglycan) and allergens (German cockroach extract and house dust mite) as well as these pathogenic mediators-induced effects on the intracellular $Ca^{2+}$ signaling in human PDL fibroblasts. Moreover, we evaluated the expression of pro-inflammatory cytokines (interleukin (IL)-$1{\beta}$, IL-6, and IL-8) and bone remodeling mediators (receptor activator of NF-${\kappa}B$ ligand and osteoprotegerin) and intracellular $Ca^{2+}$-involved effect. Bacterial pathogens and allergic mediators induced increased expression of pro-inflammatory cytokines, and these results are dependent on intracellular $Ca^{2+}$. However, bacterial pathogens and allergic mediators did not lead to increased expression of bone remodeling mediators, except lipopolysaccharide-induced effect on receptor activator of NF-${\kappa}B$ ligand expression. These experiments provide evidence that a pathogens and allergens-induced increase in $[Ca^{2+}]_i$ affects the inflammatory response in human PDL fibroblasts.

• The Korean Journal of Physiology and Pharmacology
• /
• v.28 no.3
• /
• pp.229-237
• /
• 2024

Cough is a common symptom of several respiratory diseases. However, frequent coughing from acute to chronic often causes great pain to patients. It may turn into cough variant asthma, which seriously affects people's quality of life. For cough treatment, it is dominated by over-the-counter antitussive drugs, such as asmeton, but most currently available antitussive drugs have serious side effects. Thus, there is a great need for the development of new drugs with potent cough suppressant. BALB/c mice were used to construct mice model with cough to investigate the pharmacological effects of pectolinarigenin (PEC). Hematoxylin-eosin and Masson staining were used to assess lung injury and airway remodeling, and ELISA was used to assess the level of inflammatory factor release. In addition, inflammatory cell counts were measured to assess airway inflammation. Airway hyperresponsiveness assay was used to assess respiratory resistance in mice. Finally, we used Western blotting to explore the potential mechanisms of PEC. We found that PEC could alleviate lung tissue injury and reduce the release of inflammatory factors, inhibit of cough frequency and airway wall collagen deposition in mice model with cough. Meanwhile, PEC inhibited the Ras/ERK/c-Fos pathway to exhibit antitussive effect. Therefore, PEC may be a potential drug for cough suppression.

• Journal of Periodontal and Implant Science
• /
• v.33 no.4
• /
• pp.673-691
• /
• 2003

The current interest in periodontal tissue regeneration has lead to research in bone graft, root surface treatments, guided-tissue regeneration, and the administration of growth factors as possible means of regenerating lost periodontal tissue. Several studies have shown that a strong correlation between platelet-rich plasma and the stimulation of remodeling and remineralization of grafted bone exists, resulting in a possible increase of 15-30% in the density of bone trabeculae. The purpose of this study was to study the histopathological correlation between the use of platelet-rich plasma and a bone xenograft used in conjunction with a non-resorbable guided-tissue membrane, e-PTFE, compared to a control group with regards to bone regeneration at the implant fixture site. Implant fixtures were inserted and graft materials placed into the left femur of in the experimental group, while the control group received only implant fixtures. In the first experimental group, platelet-rich plasma and BBP xenograft were placed at the implant fixture site, and the second experimental group had platelet-rich plasma, BBP xenograft, and the e-PTFE membrane placed at the fixture site. The degree of bone regeneration adjacent to the implant fixture was observed and compared histopathologically at 2 , 4, and 8 weeks after implant fixture insertion. The results of the experiment are as follows: 1. The rate of osseointegration to the fixture threads was found to be greater in the first experimental group compared to the control group. 2. The histopathological findings of the second experimental group showed rapid resorption of BBP with subsequent new bone formation replacing the resorbed BBP. 3. The second experimental group showed new bone formation in the area adjacent to the fixture threads beginning two weeks after fixture implantation, with continued bone remodeling in the areas mesial and distal to the fixture. 4. Significant new bone formation and bone remodeling was observed in both experimental groups near the implant fixture sites. 5. The rate of osseointegration at the fixture threads was greater in the second experimental group compared to the first group, and the formation of new bone and trabeculae around the fixture site occurred after the fourth week in the second experimental group. The results of the experiment suggest that a greater degree of new bone formation and osseointegration can occur at the implant fixture site by utilizing platelet-rich plasma and bone xenografts, and that these effects can be accelerated and enhanced by concurrent use of a non-resorbable guided tissue membrane.

• Korean Institute of Interior Design Journal
• /
• v.18 no.5
• /
• pp.111-118
• /
• 2009

Urban houses of traditional Korean Style are a type of habitation that happened during a transitional period when the modernization of habitation had progressed in 1930s, and also a habitation folding societal trails that had adapted and developed into urbanization together with the native traits of traditional Korean Style houses. Because they keep our style of living and the process of change just as they were, it is important work to shed light on and keep a record of it. So, this thesis arranges the contents of research on the actual condition of living, and may try to reason by analogy the changing style of residents' living through the change of space composition and the way of space usage for the urban houses of traditional Korean style that were changed by extension and remodeling of residents. As the concrete matters, it is to grasp the physical and spatial change of urban houses of traditional Korean style in accordance with extension and remodeling, and to analyze in which part and how they had been changing for the spatial composition of urban houses of traditional Korean style according to the change of living style, and especially the change toward a stand-up type of k stand-and the following traits and factors of the change toward Dining-Kitchen. The kitchen changed toward Dining-Kitchen shows some typical discrepancies depending on the location of kitchen as like a case of changing toward Dining-Kitchen from the existing location, a case of extending into the rear side of kitchen, a case of switching of location between kitchen and the inner room, and a case of changing toward Dining-Kitchen from the location of a room across from the main living room. As kitchen changed toward Dining-Kitchen like these, it shows that the connecting trace into the inner room came out, each room came to show a bit clearer function but grow smaller relation with the threshing ground, and also the function of the threshing ground came reduced.

• Journal of Periodontal and Implant Science
• /
• v.35 no.1
• /
• pp.235-250
• /
• 2005

The current interest in periodontal tissue regeneration has lead to research in bone graft, root surface treatments, guided-tissue regeneration, administration of growth factors, and the use of enamel matrix protein as possible means of regenerating lost periodontal tissue. Several studies have shown that a strong correlation between platelet-rich plasma and the stimulation of remodeling and remineralization of grafted bone exits, resulting in a possible increase of 15-30% in the density of bone trabeculae. The purpose of this study was to study the histopathological results and differences between the use of platelet-rich plasma and the use of enamel matrix $protein(Emdogain^?)$ about bone regeneration at the implant. Implant fixtures were inserted and graft materials placed into the left femur in the experimental group, while the only implant fixtures placed in the control group. In the first experimental group, platelet-rich plasma and xenograft were placed at the supracrestally placed implant site, and in the second experimental group, $Emdogain^{(R)}$ and xenograft placed at the supracrestally placed fixture site. The degree of bone regeneration adjacent to the implant fixture was observed and compared histopathologically at 2, 4, and 8 weeks after implant fixture insertion. The results of the experiment are as follows: 1. The rate of osseointegration to the fixture threads was found to be greater in the experimental group compared to in the control group. 2. The histopathological findings showed that the bone regeneration, the partial osseointegration existed at 4 weeks, and that osseointegration and bone density increaced in the experimental groups at 8 weeks. 3. The results showed that new bone formation and bone remodeling increased in the area near to the fixture in the first and second experimental groups at 8 weeks than at 4 weeks. The results showed that in the area distant from the fixture, new bone formation did not increase and bone remodeling decreased in the first experimental group at 4, 8 weeks, and that new bone formation increased in the second experimental group. 4. The histopathological findings showed that AZ deposition in the first experimental group was remarkable at 2, 8 weeks, and in the second experimental group at 2, 4, 8 weeks in the area distant from the fixture threads.