• International Journal of Naval Architecture and Ocean Engineering
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• 제6권2호
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• pp.363-379
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• 2014

In an effort to cope with recent high oil price and global warming, developments of air lubricated ships have been pursued to reduce greenhouse gas emissions and to save fuel costs by reducing the frictional resistance. In this study, reduction in the frictional resistance by air lubrication with air layers generated on the lower surface of a flat plate was investigated experimentally in the large water tunnel of SSMB. The generated air layers were observed, and changes in the local frictional drag were measured at various flow rates of injected air. The results indicated that air lubrication with air layers might be useful in reducing the frictional resistance at specific conditions of air injection. Accordingly, resistance and self-propulsion tests for a 66K DWT bulk carrier were carried out in the towing tank of SSMB to estimate the expected net power savings.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1366-1369
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• 2010

Along with the increasing need of sea development, the hydraulic stability of seabed structure on a soft seafloor ground is becoming an issue in the course of seaside development recently. However, the movement and hydraulic resistance or hydraulic stability of seafloor ground are mutually coupled with various phenomena, and there has been no clear proof for the issue, which makes it difficult to forecast. Furthermore, most researches are focused on hydraulic variables and the conditions of marine external force, while there have been few researches into the assessment in consideration of the type of a seafloor ground and the geotechnical characteristics. In addition, according to the periodic change of the flow direction, possible changes in hydraulic resistance performance of the seafloor deserves all the recognition. But there is no way to measure the hydraulic unstability of the sea ground due to tidal flow quantitatively. In this study, conventional hydraulic resistance measurement apparatus was improved to consider direction change of the current flow. Various artificial clayey soil specimens were made from Kaolinite and Jumunjin standard sand and hydraulic resistance tests were performed by changing the flow direction to validate the effect of the direction change on the scour of the seafloor.

• 대한기관식도과학회지
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• 제5권2호
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• pp.113-118
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• 1999

Background & Objectives : Nasal resistance which is halfly responsible for airway resistance is known to be influenced by hypoxia, hypercapnia, exercise, pregnancy, alcohol, ammonia and smoking. Smoking is a common part of our sociocultural environment and we have many a times been introduced to its various adverse effects, which have usually been more focused on lung problems. The purpose of this study is to determine any relationship between smoking and nasal resistance and to evaluate it's effective sites. Materials and Methods : Acoustic rhinometry was performed in 25 smokers and 25 nonsmokers who had no nasal symptoms nor abnormal rhinoscopic findings, and used an acoustic rhinometry to measure the distance from nose-piece to the C-notch, cross sectional area at the C-notch, and volume of the nasal cavity from nose-piece to 7cm. The authors compared the data between the two groups. Results : The cross sectional area at the C-notch was significantly decreased(p<0.05) in smoking group. The distance to the C-notch and the volume of nasal cavity were decreased likely in smoking group but there were no significant difference(p>0.05). Conclusion : Smoking reduced the cross sectional area at the C-notch, so increased the nasal resistance. The underlying mechanisms seems to be decreased nasal mucosal reactivity and congestion of the nasal mucosa. The authors believe there should follow more studies on pathophysiologic mechanisms and the histopathologic changes which involve the effect of smoking on nasal structures.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1071-1074
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• 2008

In this study, the behavior of dredged soil was measured by repeated tide and analyzed the change of settlements and cone penetration resistance by centrifuge model about dredged soil of Kunsan-Janghang site that maximum tidal range is 7.4m. Consequently the settlements of dredged soil by repeated tide in the 2nd month was 0.489 m. After 12th month, the total settlements was 0.524 m in the model. It meaned the settlements of dredged soil by repeated tide in the 2th month was 80% of the settlements. Also, with the lapse of time, cone penetration resistance increased centrifuge model test for catching the strength change of dredged soil by repeated tide. After 10th month, there were not almost changes. cone penetration resistance in 10th month was measured more 3.5~5.6 times than that in its early stages. Also, with the lapse of time, cone penetration resistance increased almost linearly. And, when we surveyed the relation between cone penetration resistance and time, as depth increased, cone penetration resistance rose.

• 중환자간호학회지
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• 제9권2호
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• pp.48-60
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• 2016

Purpose: The purpose of this study was to identify the attributes of the concept, of psychological resistance to antihypertensive medication. Methods: The study was conducted in accordance with Walker and Avant's conceptual analysis process. We reviewed 47 related studies selected from 4 international and Korean databases including Medline, CINAHL, NDSL, and RISS to perform the analytical processes from January 1980 to September 2015. Results: The attributes of psychological resistance to antihypertensive medication include 1) reservation, 2) opposition, 3) denial, 4) refusal, and 5) seeking alternative therapy. The antecedents of the concept can be classified into patient factors such as reactance trait and knowledge deficit, provider factors, interpersonal factors, and environmental factors. The consequences of psychological resistance to antihypertensive medication are non-compliance, deterioration of the disease, developing complications, increased anxiety, and changes in life. Conclusions: The concept of psycho logical resistance to antihypertensive medication can provide guidance for the development of an intervention program that promotes the compliance to medication regimen of hypertensive patients. Further research needs to be done to develop a measurement tool for psychological resistance to antihypertensive medication.

• Natural Product Sciences
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• 제19권4호
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• pp.316-323
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• 2013

Adipose tissue-derived chronic inflammation contributes to development of insulin resistance in obesity, leading to type 2 diabetes and cardiovascular disease. Baicalin, a flavonoid, has antioxidant, anti-inflammatory, antihyperglycemic, anti-adipogenic, and antiobesity effects. However, whether baicalin attenuates adipose tissue-derived development of insulin resistance remains still unclear. This study was to investigate effect of baicalin on the inflammatory changes involved in the development of insulin resistance in adipose tissue. RAW 264.7 cells and differentiated 3T3-L1 adipocytes were pretreated with various concentrations of baicalin in complete media for 1 h and then cultured in the presence or absence of LPS or TNF-${\alpha}$. Our results demonstrated that baicalin remarkably inhibited LPS-induced production of TNF-${\alpha}$, IL-6, and NO by RAW 264.7 cells in a dose-dependent manner. Baicalin also inhibited TNF-${\alpha}$-induced production of IL-6 and $PGE_2$ in differentiated 3T3-L1 cells in a dose-dependent manner, while upregulated TNF-${\alpha}$-suppressed expression of adiponectin and PPAR-${\gamma}$ mRNA and IRS-1 protein. These findings suggest that baicalin may prevent the adipose tissue-derived development of insulin resistance in obesity.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7913-7917
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• 2014

Apoptotic cell death plays a predominant role in histone deacetylase (HDAC) inhibitor-induced cytotoxicity. Nuclear morphological changes and activation of apoptotic executors are involved in CTS203-induced cell death. However, emerging issues of HDAC inhibitor-resistance have been observed in patients. Herein, MCF-7 cells were continuously exposed to CTS203 until the derived cells could proliferate normally in its presence. The newly obtained CTS203-resistant cells were nominated as MCF-7/203R. Compared to MCF-7 original cells, the MCF-7/203R cells were less sensitive to CTS203-induced apoptosis, with a minimal 6-fold higher $IC_{50}$ value. In contrast, the expression of Beclin-1 was dramatically up-regulated, positively correlated to the acquisition of CTS203-resistance. Our results revealed the participation of autophagy in acquired HDAC inhibitor-resistance and further identified Beclin-1 as a promising target for anti-drug resistance.

• Journal of Welding and Joining
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• 제22권4호
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• pp.35-42
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• 2004

Contact tips are required to have a higher resistance to wear and thus to have an extended life time under the advanced GMAW welding process. Several requirements have been specified and employed by domestic industries for selecting their tips for such a purpose. However no attempt has been made to justify their requirements based on the experimental data of wear resistance or life time of contact tips. In this study, five different contact tips with three different compositions were employed for actual GMA welding up to 4 hours and were evaluated their wear resistance by measuring in every one hour the area of enlarged hole at the exit side. Experimental results clearly showed that the Cr-containing tips strengthened by precipitation hardening have much better resistance to wear than those made by work hardening. It was further noticed that Cr is an excellent alloying element for improving the wear resistance of contact tips only when it is in an properly aged condition. Initial hardness may play some role in the early stage of wear but not in the later stage of welding because the microstructure of tip changes significantly by the prolonged exposure to welding arc heat. Based on these results, critical review has been made on the current requirements employed by domestic industries. Of importance is that a new guideline has been confirmed to be more reasonable.

• 대한정형도수물리치료학회지
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• 제14권1호
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• pp.15-23
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• 2008

Purpose : To evaluate the effects of elastic resistance exercise of lumbo-pelvic region and upper limbs muscle on equilibrium ability and shoulder pain of the elderly. Methods : The subject consisted of sixteen healthy elderly people(14 females. 2 males). They were from 61 to 83 years old and the mean age was 68.06. All subjects were assigned only the elastic resistance exercise group. The subject group received elastic resistance exercise for about 60 minutes per day, two times per weeks, during 8 weeks period. A Stop watch was used to measure static equilibrium ability and dynamic equilibrium ability and then pressure algometer was used to measure shoulder press pain threshold. All measurements of each subjects were measured at pre-experiment and post-experiment stage. SPSS 12.0 program was used to compile results. A Paired samples t-test was conducted to examine changes of static equilibrium, dynamic equilibrium and shoulder press pain threshold between pre-experiment and post-experiment. Results : The static equilibrium ability, dynamic equilibrium ability and shoulder press pain threshold were significantly differences between pre-experiment and post-experiment(p<.05). Conclusion : This data suggests that an eight week elastic resistance exercise improved static equilibrium ability and dynamic equilibrium ability and then reduced shoulder pain.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권4호
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• pp.147-151
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• 2002

The resistances of metal2 contact to metall and poly Si are checked by various RF etch conditions in terms of pre-cleaning. The changes of resistance are evaluated by statistical analysis method(SAS) for the AC bias power, coil power and RF target. The contact area on poly Si is shown by TEM image and the distributions of contact resistance according to ar etch target and RTP are investigated. The RTP groups have larger variations than normal RF etch targets. When the RF etch target becomes lower and coil power becomes higher, the resistances of metal2 contact to metals and poly Si have lower contact resistance. But the condition of AC bias power did not satisfied low meta12 contacts resistance for metall and poly Si simultaneously. The R-square of ststistical analysis was 0.98 for resistances of meta12 contact to poly Si and 0.87 for resistances of meta12 contact to metall.