• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.9
• /
• pp.745-751
• /
• 2012

Hybrid rocket shows interesting characteristics of complicated mixing layers developed by interactions between turbulent oxidizer flow and mass flow from surface due to fuel vaporization. In this study, compressible LES with a ring structure attached at the entrance of the combustor are performed. According to one recent report, adding a ring structure in the middle of the combustor helps increasing regression rate. From the numerical results, it is seen that vortex structures near the wall becomes stronger due to the interaction with surface mass injection, and the local heat flux increases due to the vortices. This phenomenon is obviously related to the generation of dimple structures which are seen in the number of experiments. Also, the ring structure at the entrance induces strong vortex flow which enhances heat transfer to the wall surface and mixing between fuel and oxidizer as well as reaction efficiency.

• Journal of Pharmacopuncture
• /
• v.21 no.3
• /
• pp.203-206
• /
• 2018

Objectives: There is an increasing number of complex diseases that are progressively more difficult to be controlled using the conventional "single compound, single target" approach as demonstrated in our current modern drug development. TCM might be the new cornerstone of treatment alternative when the current treatment option is no longer as effective or that we have exhausted it as an option. Orthogonal stimulus-response compatibility group study is one of the most frequently employed formulas to produce optimal herbal combination for treatment of multi-syndromic diseases. This approach could solve the relatively low efficacy single drug therapy usage and chronic adverse effects caused by long terms administration of drugs that has been reported in the field of pharmacology and medicine Methods: The present review was based on the Science Direct database search for those related to the TCM and the development of antihypertensive TCM herbal combination using orthogonal stimulus-response compatibility group studies approach. Results: Recent studies have demonstrated that the orthogonal stimulus-response compatibility group study approach was most frequently used to formulate TCM herbal combination based on the TCM principles upon the selection of herbs, and the resulting formulated TCM formula exhibited desired outcomes in treating one of global concerned complex multi-syndromic diseases, the hypertension. These promising therapeutic effects were claimed to have been attributed by the holistic signaling mechanism pathways employed by the crude combination of herbs. Conclusion: The present review could serve as a guide and prove the feasibility of TCM principles to be used for future pharmacological drug research development.

• Journal of Korean Medicine Rehabilitation
• /
• v.25 no.2
• /
• pp.65-72
• /
• 2015

Objectives To investigate and validate potential standard compounds for standardization of Sinbaro3 pharmacopuncture prepared at OO Hospital of Korean Medicine. Methods Sinbaro3 pharmacopuncture was prepared by extraction, purification and hydrolysis of Harpagophytum procumbens, and various potential standard compounds were quantified through HPLC-UV and HPLC-MS analysis. Validation was examined by assessing specificity, linearity, precision, and accuracy. Results The retention time of harpagide and cinnamic acid were 15.2 min and 28.2 min, respectively, and both showed good linearity in analysis by concentration at 0.9999 and 0.9998, respectively. Intra-day variation of precision was 0.0015~0.0045% and 0.0058~0.1629%, while inter-day variation of precision was 0.0011~0.0243% and 0.0098~0.1629%, and that of accuracy was 99.53~99.89% and 99.50~99.91%, respectively. Conclusions Harpagide and cinnamic acid, which are hydrolyzates of harpagoside within Sinbaro3 pharmacopuncture, were both validated using HPLC-MS and HPLC-UV analysis, and Sinbaro3 pharmacopuncture contained 78.41 ug/ml harpagide, and 2.05 ug/ml cinnamic acid.

• Macromolecular Research
• /
• v.12 no.4
• /
• pp.422-426
• /
• 2004

Solid polymer electrolytes based on poly(ethylene glycol)-polyurethane (PEG-PU) complexed with LiClO$_4$ salt have been prepared by the solvent casting method. A PEG-PU material (PEG:4,4'-diphenylmethane diisocyanate: l,4-butanediol = 1:2:1) was synthesized through a typical two-step condensation reaction. We investigated the effects of the salt concentration on the ionic conductivity ($\sigma$) and the glass transition temperature (T$_{g}$ ) of the complex electrolytes by using alternating current impedance spectroscopy, differential scanning calorimetry, and dynamic mechanical thermal analysis. The measured values of both $\sigma$ and T$_{g}$ exhibited similar tendencies in that they had maxima within the range studied, probably because of two opposite effects, i.e., the increased number of carrier ions and the decreased chain mobility (or increased T$_{g}$ ) caused by the increase in the salt concentration. The highest conductivity, on the order of 2.43 ${\times}$ 10$^{6}$ S$cm^{-1}$ /, was obtained at an [O]/[Li$^{+}$] ratio of ca. 16 (0.92 ㏖ salt per kg of matrix polymer).

• The Journal of Korean Obstetrics and Gynecology
• /
• v.28 no.4
• /
• pp.11-20
• /
• 2015

Objectives The purpose of this study was to examine the relationship between cold hypersensitivity and bone mineral density. Methods 28 outpatients who visited OO University Oriental Hospital from July 11th, 2013 to August 28th, 2013 were analyzed. Patients were subjected to thermometer, and those with thermal difference greater than 0.3 ℃ between upper arm and palm and also with more than VAS 4 of cold hypersensitivity were diagnosed with cold sensitivity. Lumba spine (L2-4) and heel bone measurement were obtained on dual energy X-ray absorptiometry (DEXA) and Quantitative Computed Tomography (QCT). Results 1. There was statistically significant correlation between T-score of DEXA and body weight (0.522), BMI (0.643), OSTA (Osteoporosis elf-assesment Tool for Asians, 0.579), BMI, T-score and Z-score of QCT. OSTA and T-score of QCT (0.521) also had statistically significance. 2. There was no statistically significant correlation between body fat, abdominal obesity rate, degree of cold hypersensitivity, upper arm and palm's temperature difference, palm temperature, height and Z-score, T-score of QCT or T-sore of DEXA. Conclusions Bone mineral density was lower in women who had cold hypersensitivity of hand and feet. But there was no statistically significant correlation between bone mineral density and degree of cold hypersensitivity, upper arm and palm’s temperature difference.

• YAKHAK HOEJI
• /
• v.41 no.1
• /
• pp.38-47
• /
• 1997

Using a concentric cylinder type, rheometer. the steady shear flow properties of vaseline were measured over the temperature range of 20~70${\circ}$C. In this paper, the shea rate and temperature dependencies of its flow behavior were investigated and the validity of some flow models was examined. In addition, the flow characteristics over a wide temperature range were quantitatively evaluated by calculating the various material parameters. Main findings obtained from this study can be summarized as follows: (1) At relatively lower temperature range, vaseline is a plastic fluid with a yield stress and its flow behavior shows shear-thinning characteristics. (2) As the temperature increases, the value of a yield stress and the degree of shear-thinning become smaller, consequently, the Newtonian flow behavior occurs at a lower shear rate range. (3) At temperature range lower than 45${\circ}$C, the flow behavior shows much stronger temperature dependence, and a larger activation energy is needed for flow. (4) The Herschel-Bulkley model is the most effective one g$^3$ to predict the flow behavior of vaseline having a yield stress. The validity of the Bingham and Casson models becomes more available with increasing temperature. The flow behavior of vaseline at temperature range higher than 45${\circ}$C can be perfectly described by the Newton model.

• Journal of the Society of Naval Architects of Korea
• /
• v.45 no.4
• /
• pp.441-454
• /
• 2008

Shipyard design and equipments layout problem, which are directly linked with the productivity of ship production, is an important issue serving as reference data of production plan for later massive production of ships. So far in many cases, design of a shipyard has been relying on the experienced engineers in shipbuilding, resulting in sporadic and poorly organized processes. And thus, economic losses as well as trials and errors in that accord have been pointed out as inevitable problems. This paper extracts a checklist of major elements to fine tune the shipbuilding yard designing process and the input/output data based on the simulation based shipbuilding yard layout designing framework and methodology proposed in existing researches, and executed initial architecture to develop software that integrates all the relevant processes and designing tools. In this course, both user request and design data by the steps are arranged and organized in the proposed layout design template form. In addition, simulation is done based on the parent shipbuilding process planning and scheduling data of the ship product, shipbuilding process and work stage facilities that constitute shipbuilding yard, and design items are verified and optimized with the layout and equipment list showing optimal process planning and scheduling effects. All the contents of this paper are based on simulation based shipbuilding yard layout designing methodology, and initial architecture processes are based on object oriented development methodology and system engineering methods.

• The Korean Journal of Ecology
• /
• v.18 no.1
• /
• pp.1-15
• /
• 1995

Alakline phosphatase activity (AP A) as a phosphorus deficiency measurement in flowing waters and of microhabitats (rocks, wood, leaves, and sediments) was measured and its relationship to flux of nutrients and response to rainfall events were determined for two geologically different streams in west Alabama from August to November. Results indicated water column AP A in both streams had a low correlation with levels of orthophosphate, total organic phosphorus, nitrate, ammonia, dissolved organic carbon, and discharge (r=0.075-0.583; n=g-IU. Communities on rock surfaces showed a higher AP A level than those on wood and leaves. Sediment passed through a $106{\mu}m$ sieve showed 2-9 times higher AP A level than material passed through $425{\mu}m$ sieve. The first storm after drought at Yellow Creek introduced substantial quantities of DOC (2.5 times baseflow concentrations) and $N0_3-N$ (5.8 times baseflow concentrations) which did not affect AP A significantly. The second storm at Little Schultz Creek caused minor changes in nutrient cocentrations; however $N0_3-N$ levels and AP A were drastically lower due to the dilution effect. Retention of stream water AP A at Yellow Creek and Little Schultz Creek on $0.45{\mu}m$ filter (54 and 43%, respectively) and $0.22{\mu}m$ (83 and 77% of total APA. respectively) indicated more free dissolved portion of the enzyme was present at Little Schultz Creek. Little Schultz Creek (with carbonate and with a higher productivity and biomass) showed a consistantly greater AP A activity $(132{\pm}54\;{\mu}M{\cdot}1^{-1}{\cdot}min^{-I};\;n=g)$ than Yellow Creek $(41{\pm}23\;{\mu}M{\cdot}1^{-I}{\cdot}min^{-I}$, with a sandstone substrate; n=l1, $p{\leq}O.OO1)$. Overall, a greater APA on all microhabitats and the presence of more dissolved enzyme in Little Schultz Creek during the study period may indicates it is more P deficient than Yellow Creek.

• KSBB Journal
• /
• v.10 no.4
• /
• pp.393-400
• /
• 1995

As a part of the .study on the multiple propagation and use of Dendropanax mcrbifera, distribution of this tree and component analysis of Golden Lacquer were investigated to reappear the Golden Lacquer, traditional paints. These results were summarized as follows. The natural growth habitat of Dendropanax morbifera was observed in 8 sites(Wando, Sanghwangbong, etc.), we could be found that Duryun nountain in Haenam for the first time. Dendropunax morbifera has grown from 100 to 450m above the sea level, appeared high frequency in the 200m. The soil pH of natural growth site was pH 4.9 to pH 5.8. Dendropanax morbifera grew in the area containing considerable moisture in that its contents was 16.5% to 27.4%. In community observation, dominance and community index of Bogildo and Chejudo was 3.3 in the forest tree layer and Wando was showed in the sub-forest tree layer mainly. In the growth conditions, Bogildo appeared the highest growth state that diameter of height of human chest was 1.0 to 20cm and tree height was 0.2 to 9m. As result of IR and GC-MS analysis, main component of Golden Lacquer was ${\beta}$-selinene and capnellane-8-one.

• Journal of the Society of Naval Architects of Korea
• /
• v.50 no.4
• /
• pp.262-271
• /
• 2013

Owing to the development of mobile communication technology during the last a few years, the number of users of mobile devices such as the smartphone and the tablet PC has increased rapidly. As a result, the range of applications of the mobile devices has also been greatly expanded from an application for the convenience of daily life to an application for assisting the operations of industrial fields. Especially, portability of mobile devices can provide great help in collecting and using information on the production site. In shipbuilding production processes, it is difficult to collect changes of circumstance in the field and reflect the changes to schedule due to the low production automation rate and frequent changes in schedule. In this study, we propose a system to solve the problems of shipbuilding production processes such as the ones described above by using mobile devices. First of all, we organize the production information and production processes of the panel line through the analysis of shipyard panel line operations. Next, we have developed a system that can support the production execution plan of the panel line and monitor the production processes in the field. The system was developed utilizing application virtualization to allow access to the system from various platforms of mobile devices and PC's. The system was implemented using ooCBD methodology considering the future expansion of the system and ease of maintenance.