• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.403-410
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• 2007

The purpose of this study was to investigate whether rhBMP-2 (BMP2) could induce synergistic effect with $Pro-Root^{(R)}$ MTA (MTA) in pulpotomized teeth in the rats. Healthy upper first molars from thirty-two, 10 weeks old, Sprague-Dawley rats were used for this investigation. The molars were exposed with round bur, and light pressure was applied with sterilized cotton to control hemorrhage. 1.2 grams of MTA cement was placed in right first molars as a control group. In left first molars, $1\;{\mu}g$ of BMP2 was additionally placed on exposed pulps with MTA. All cavities were back-filled with light-cured glass-ionomer cements. The rats were sacrificed after 2 weeks and 7 weeks, respectively. Then histologic sections were made and assessed by light microscopy. Data were statistically analyzed via student t-test with SPSSWIN 12.0 program (p < 0.05). Inflammation observed in 2 weeks groups were severe compared to the 7 weeks groups. But the differences were not statistically significant. BMP2-addition groups had less inflammation than MTA groups in both periods, though these differences were also not statistically significant. In conclusion, the combination of BMP2 and MTA showed no differences with MTA only for pulpotomy of rat teeth.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.181-189
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• 2012

We developed a new high-yield synthesis method of free-standing germanium nanocrystals (Ge NCs) by means of the gas-phase photolysis of tetramethyl germanium in a closed reactor using an Nd-YAG pulsed laser. Size control (5-100 nm) can be simply achieved using a quenching gas. The $Ge_{1-x}Si_x$ NCs were synthesized by the photolysis of a tetramethyl silicon gas mixture and their composition was controlled by the partial pressure of precursors. The as-grown NCs are sheathed with thin (1-2 nm) carbon layers, and well dispersed to form a stable colloidal solution. Both Ge NC and Ge-RGO hybrids exhibit excellent cycling performance and high capacity of the lithium ion battery (800 and 1100 mAh/g after 50 cycles, respectively) as promising anode materials for the development of high-performance lithium batteries. This novel synthesis method of Ge NCs is expected to contribute to expand their applications in high-performance energy conversion systems.

• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.31-42
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• 2000

Consolidation and permeability are major engineering properties of soil. In clay, coefficient of permeability and consolidation can be calculated by incremental loading consolidation test. However, it is known that the incremental loading test has several deficiencies including long testing time, non-uniform stress state, very soft clay and problem of back pressure saturation. Specially, it is not performed with horizontal consolidation test. Several methods have been proposed for obtaining reliable values of $C_v$. Among these, the square root of time-fitting method proposed by Taylor(1948) and logarithm of time-fitting method, also called Casagrande's method, are used extensively in soil engineering practice. But these methods are not amenable for the absence of initial linear portion and have the difficulties involved in distinguishing secondary compression from primary compression. Rowecell consolidation tests were carried out in this study with different trimming axis and sample size. The results were compared with those of other methods; Casagrande,$Taylor,\; Casagrande,\; Hyperbolic,\; \delta/t-logt$. From the results, we explained a relationship between horizontal coefficient of permeability and void ratio was obtained. Finally, the directly measured horizontal coefficient of permeability obtained by using the Rowecell was compared with the permeability derived indirectly from the consolidation test result.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.4
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• pp.362-367
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• 2017

This study was conducted to compare the particulate removal efficiency of the developed diesel particulate filter using various measurement methods in a high-speed marine diesel engine. A four-stroke mechanical marine diesel engine is used for the test, which has a maximum output of 403 kW and is coupled to an AC dynamometer to control engine speed and load. The test was conducted based on four steady-state engine operating conditions of E3 engine test cycle for the measurement of PM and soot removal efficiency using partial dilution method considered as gravimetric method and filter smoke number method as light absorption method, respectively. As a result of the removal efficiency measurement according to the application of diesel particulate filter, particulate matter was reduced from 76% to 91% and the soot was reduced by more than 90% while meeting the permissible engine back pressure. From these results, the applicability of diesel particulate filter adopted in high-speed marine diesel engines could be confirmed. In addition, based on the result that the particulate removal efficiency varies with different measurement methods, the necessity of unification of these methods could be identified.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.11 no.1
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• pp.41-51
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• 2016

Objectives : This study is planned to classify Correlation between Cobbs Angle of Lumbar scoliosis and prevalence of Lumbar Intervertebral Disc. Methods : We Measured the lumbar scoliosis angle of the 114men and 91 women patients with lumbar pain in Bucheon Jaseng Korean Medicine Hospital. We use Cobb's angle method for measuring the lumbar scoliosis. And We use Magentic Resonance Imaging(MRI) for classifying the patient who has lumbar intervertebral disc or not. Results : 1.There was no statistical relation between the Cobbs angle and gender(P>0.05) 2.There was no statistical relation between the Cobbs angle and age(P>0.05) 3.There was significant relation between the direction of lumbar scoliosis and the direction of disc herniation(P<0.05) 4.There was no statistical relation between on the Cobbs angle and disc herniation. The more severe of lumbar scoliosis has not tendency of disc herniation. 5.There was no statistical relation between lumbar scoliosis Cobbs Angle on HIVD of L-spine patient and direction of disc herniation on horizontal plane. Conclusions : The direction of disc herniation has tendency of the opposite direction of lumbar scoliosis. When disc herniation, opposite side bending broad intervertebral foramen and reduce pressure.

• Journal of Oriental Neuropsychiatry
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• v.7 no.1
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• pp.1-13
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• 1996

1. Out of 21 examples on a clinical base Alzheimer type dementia were 8 examples(38%), 11 vascular types(52%), 1 Alzheimer and vascular mixed type and rest 1 was secondary dementia type(NPH).2. Between the genders, there were 5 males and 3 females for Alzheimer types, 6 males and 5 females for the vascular types, 1 male for Alzheimer and vascular mixed type, and 1 female for secondary dementia type(NPH).3. For the degrees of Alzheimer type dementia there were 2 mild dementia, 4 moderate dementia, and 2 severe dementia. 4. Among the Alzheimer types 2 mild dementia were almost recovered back to normal in approximately 2 months, 2of 4 moderate dementia became significantly better in approximately 2 months and recovered to almost normal state in 3 to 5 months. The rest 2 have been under treatment for 3 months, but showed a little improvement. Out of 2 severe dementia examples, one showed a little improvement even if it has been under treatment over 2 years. The other example did not show any improvement, but dementia did not proceed any more.5. Among the 11 vascular examples, 7 recovered in 2 to 3 months, 1 in 5 months, 2 recovered in a year, and the treatment was stopped arbitrary for the last one.6 In the case of Alzheimer and vascular mixed type dementia, even the moderate dementia did not show any apparent result in 6 months.7. For NPHI (Normal Pressure Hydrocephalus), there was an improvement on dementia in 2 months after the treatment, but gait disturbance and urinary incontinence did not show any noticeable difference. As a conclusion, almost all the Alzheimer and vascular type patients recovered, but the treatment periods varied depending on the types of the dementia and the degree of seriousness, especially in the case of the severe Alzheimer patients, the treatment oniy suppression the progression of the dementia. The most important aspect from clinical point of view was even if almost all the patients were almost completely cired, they need to keep being cured for a long period of time. The method with respect to Four Constitutions is thought of the most desirable.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.1
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• pp.65-75
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• 1990

There have been many methods for measuring the injection rate of diesel engines, but the results of them are not always identical and the reason for the discordance is not clear. Besides, a single shot injection equipment has been used for the fuel spray and the combustion research of diesel engines, but the results of experiment using the equipment don't apply to a volleyed shot injection of real engines. This paper investigates the merits and faults of the Bosch's method and the Zeuch's method, at the same, this paper also compares the injection rates of single shot inject rates of single shot injection and a volleyed shot injected by the Bosch's method. the results are summarized as follows: (1) The measurement error of the Bosch's method is about $\pm$1%, therefore, its accuracy is reliable. (2) By the Bosch's method, as the speed and the load of fuel pump increase, the injection rate becomes higher, on the contrary, the injection period(ms) shortens as the speed increases and the load decreases. (3) In this experiment, the injection rate of a single shot injection is lower than that of a volleyed shot injection under the same conditions. (4) The bulk modulus of elasticity using the Zeuch's method increases in proportion to the back pressure. (5) The Zeuch's method is less accurate than the Bosch's method.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1296-1302
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• 2005

Laminariae Thallus has been known to be effective for the treatment of obesity. Te show the effectiveness of Laminariae Thallus in a more scientific way, Laminariae Thallus extract was prepared and evaluated in high fat diet rats by measuring the changes of body weight and lipid metabolism as described briefly below. 200 g of crushed Laminariae Thallus was extracted with methyl alcohol. The extract was evaporated under reduced pressure to give 14.4g. For 10 weeks, control group rat were ingested high fat diet, while the test group rat were fed with a fat diet pius Laminariae Thallus extract. Normal group was fed with normal diet. 150 mg of Laminariae Thallus extract per 1 kg of body weight was added to the diet in a test group rats. Control group rats on a high fat diet gained weight significantly, whereas the test group rats on a high fat diet plus Laminariae Thallus extract gained weight less. Significant increase of liver weight caused in a high fat diet was also inhibited by the Laminariae Thallus extract treatment. Total lipid, triglyceride, phospholipid and total cholesterol levels of serum in the high fat diet rats were remarkably increased, whereas their levels on a high fat diet plus Laminariae Thallus extract were less increased. While serum HDL-cholesterol levels was remarkably decreased in a high fat diet, its level was less decreased in a high fat diet plus Laminariae Thallus extract. Furthermore, we observed that the activities of hepatic acetyl-CoA carboxylase and fatty acid synthetase increased in a high fat diet, while their activities in a high fat diet plus Laminariae Thallus extract were getting back nearly to the normal levels of normal diet rats. These result showed that the obesity caused by a high fat diet was effectively inhibited by a Laminariae Thallus extract. Our results also showed that the abnormal lipid metabolism caused by a high fat diet was effectively cured by adding Laminariae Thallus extract.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.377-377
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• 2012

Microprocessor technology now relies on copper for most of its electrical interconnections. Because of the high diffusivity of copper, Atomic layer deposition (ALD) $TaN_x$ is used as a diffusion barrier to prevent copper diffusion into the Si or $SiO_2$. Another problem with copper is that it has weak adhesion to most materials. Strong adhesion to copper is an essential characteristic for the new barrier layer because copper films prepared by electroplating peel off easily in the damascene process. Thus adhesion-enhancing layer of cobalt is placed between the $TaN_x$ and the copper. Because, cobalt has strong adhesion to the copper layer and possible seedless electro-plating of copper. Until now, metal film has generally been deposited by physical vapor deposition. However, one draw-back of this method is poor step coverage in applications of ultralarge-scale integration metallization technology. Metal organic chemical vapor deposition (MOCVD) is a good approach to address this problem. In addition, the MOCVD method has several advantages, such as conformal coverage, uniform deposition over large substrate areas and less substrate damage. For this reasons, cobalt films have been studied using MOCVD and various metal-organic precursors. In this study, we used $C_{12}H_{10}O_6(Co)_2$ (dicobalt hexacarbonyl tert-butylacetylene, CCTBA) as a cobalt precursor because of its high vapor pressure and volatility, a liquid state and its excellent thermal stability under normal conditions. Furthermore, the cobalt film was also deposited at various $H_2/NH_3$ gas ratio(1, 1:1,2,6,8) producing pure cobalt thin films with excellent conformality. Compared to MOCVD cobalt using $H_2$ gas as a reactant, the cobalt thin film deposited by MOCVD using $H_2$ with $NH_3$ showed a low roughness, a low resistivity, and a low carbon impurity. It was found that Co/$TaN_x$ film can achieve a low resistivity of $90{\mu}{\Omega}-cm$, a low root-mean-square roughness of 0.97 nm at a growth temperature of $150^{\circ}C$ and a low carbon impurity of 4~6% carbon concentration.

• Journal of the Korean Magnetics Society
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• v.25 no.6
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• pp.189-197
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• 2015

As enforced the regulation of fuel efficiency, the electrification of automotive components in internal combustion vehicle has been applied instead of hydraulic pressure. A typical example of such parts is the EPS (electric power steering), and it is applied to most automotive at present. In electric power steering system, the core component is motor. The reduction of cogging torque and torque ripple is required to improve steering feeling and reduce NVH (Noise Vibration Harshness) in EPS. Generally the skewed design of stator or rotor is applied in order to reduce cogging torque and torque ripple. This paper propose the design and analysis methodology of Brusheless PMSM (Permanent Magnet Synchronous Motor) which is applied to skewed stator. The proposed methodology is as follows: First Intial Design PMSM with skewed stator for EPS, Second Optimal design using RSM (Response surface method), Third Performance Analysis such as Phase Back EMF, Inductance, Load torque using FEA (Finite Element Method). Finally, the reliability of proposed design methodology will be verified through the experiments of prototype sample.