• Geomechanics and Engineering
• /
• 제13권4호
• /
• pp.671-683
• /
• 2017

Groundwater control is a significant issue in most underground construction. An estimate of the inflow rate is required to size the pumping system, and treatment plant facilities for construction planning and cost assessment. An estimate of the excavation-induced drawdown of the initial groundwater level is required to evaluate potential environmental impacts. Analytical and empirical methods used in current engineering practice do not adequately account for the effect of the jointed-rock-mass anisotropy and heterogeneity. The impact of geostructural anisotropy of fractured rocks on tunnel inflows is addressed and the limitations of analytical solutions assuming isotropic hydraulic conductivity are discussed. In this paper the unexcavated Zagros tunnel route has been classified from groundwater flow point of view based on the combination of observed water inflow and numerical modeling results. Results show that, in this hard rock tunnel, flow usually concentrates in some areas, and much of the tunnel is dry. So the remaining unexcavated Zagros tunnel route has been categorized into three categories including high Risk, moderately risk and low risk. Results show that around 60 m of tunnel (3%) length can conduit the large amount of water into tunnel and categorized into high risk zone and about 45% of tunnel route has moderately risk. The reason is that, in this tunnel, most of the water flows in rock fractures and fractures typically occur in a clustered pattern rather than in a regular or random pattern.

• 전기학회논문지
• /
• 제60권10호
• /
• pp.1846-1857
• /
• 2011

This paper deals with design and analysis of surface-mounted PM (SPM) motor for compressor of air-conditioning system for electric vehicle applications according to slot/pole combination. First, required torque-speed curve characteristics are determined from operating conditions of the compressor. Restricted conditions such as motor size limit and current density are also determined. And then, under same rated and restricted conditions, twelve models which have different slot/pole combinations each other are designed for various pole arc/pitch ratio using simple equations and 2-d finite element (FE) analyses. Designed models are analyzed and compared in terms of back-emf THD, cogging torque, torque ripple, power losses, efficiency, etc. On the basis of analysis results, it is found that the motor with a 6-pole PM rotor and a 27-slot stator has most outstanding performances in electromagnetic aspects. Finally, through the mechanical modal analysis and demagnetization analysis, it is concluded that the determined motor is most suitable for the compressor of air-conditioning system for electric vehicles.

• Journal of Pharmaceutical Investigation
• /
• 제31권3호
• /
• pp.181-184
• /
• 2001

The purpose of this study was to develop transdermal drug delivery system (TDDS) for the combination of physostigmine and procyclidine. The effects of various pressure sensitive adhesives (PSA) on the percutaneous absorption of procyclidine across hairless mouse skin were evaluated to select an appropriate PSA. In addition, the influences of various vehicles on the percutaneous absorption of procyclidine from PSA matrix across hairless mouse skin were evaluated using flow-through diffusion cell system at $37^{\circ}C$. Physostigmine did not have any influence on the permeation rate of procyclidine. The flux of procyclidine was the highest in silicone and PIB and was relatively lower in SIS, Acryl, and SBS adhesive matrices, however, their use was limited by the crystallization of the drug in the matrix. Among acrylic adhesives, the permeability of procyclidine was the highest from poly (ethylene oxide) grafted acrylic adhesive. Some enhancers show different enhancing effect depending on the drug, however, many of the tested enhancers showed enhancing effect for the permeation of both procyclidine and physostigmine to some extent. $Crovol^{\circledR}$ EP 40 showed the highest enhancing effect on the permeation of both compounds. The size of TDDS to provide required permeation rate was estimated to be $35\;cm^2$ based on available information.

• Wind and Structures
• /
• 제30권3호
• /
• pp.219-229
• /
• 2020

Net pressures on roofs and walls of buildings are dependent on the internal and external pressure fluctuations. The variation of internal and external pressures are influenced by the size and location of the openings. The correlation of external and internal pressure influences the net pressures acting on cladding on different parts of the roof and walls. The peak internal and peak external pressures do not occur simultaneously, therefore, a reduction can be applied to the peak internal and external pressures to obtain a peak net pressure for cladding design. A 1:200 scale wind tunnel model study was conducted to determine the correlations of external and internal pressures and effective reduction to net pressures (i.e., net pressure factors, F_C) for roof and wall cladding. The results show that external and internal pressures on the windward roof and wall edges are well correlated. The largest ${\mathcal{C}}_{{\check{p},net}$, highest correlation coefficient and the highest F_C are obtained for different wind directions within 90° ≤ θ ≤ 135°, where the large openings are on the windward wall. The study also gives net pressure factors F_C for areas on the roof and wall cladding for nominally sealed buildings and the buildings with a large windward wall opening. These factors indicate that a 5% to 10% reduction to the action combination factor, K_C specified in AS/NZS 1170.2(2011) is possible for some critical design scenarios.

• 대한한방내과학회지
• /
• 제19권2호
• /
• pp.219-232
• /
• 1998

Paljintanggagmbang has been used for cure of tumor as a traditional medicine without any experimental evidence to support the rational basis for its clinical use. This study was carried out to evaluate. the possible therapeutic or antitumoral effects of Paljintanggagmbang extract against tumor, and to carry out some mechanisms responsible for its effect. Experimental studis were performed for measurement of Humoral and Cellular Immune Response and Phagocytosis in Mice treated with mitomytion C(MMC) and Paljintanggagmbang alone and combination. The results obtained in this study were as follows 1. The adminstration of Paljintanggagmbang extract decresed size of tumors cell which MCA induced. 2. The adminstration of Paljintanggagmbang extract decresed growth of the tumors which S 180 transplant. 3. The adminstration of Paljintanggagmbang extract decresed reproduction of A549, Hep3b, 3LL cell and S 180 in vivo. 4. The adminstration of Paljintanggagmbang extract incresed activity of the NK cell. These results also suggested that effect of Paljintanggagmbang might be chiefly due to nonspecific enhancement of Humoral and Cellular Immune Response and Phagocytosis in Mice treated with MMC and Paljintanggagmbang alone and combination.

• 한국기계가공학회지
• /
• 제11권5호
• /
• pp.104-108
• /
• 2012

Recently, small scale hydropower needs to be developed due to its clean, renewable and abundant energy resources. However, suitable draft of hydro-turbine body in combination with differences in wheel blade shapes is not determined yet in the range of small hydropower and it is necessary to study for the effective draft in combination with type. Therefore, watermill shaped of 250mm diameter. hydro-turbine aiming 20 watt class generator is adopted in this study because of its simple structure and high possibility of applying to small hydropower. The result shows that effective draft for the turbine body is variable concerning the size of turbine and flow rate of water. Thus, the difference of water depth between fore and aft turbine body contributes to the increase of torque, angular momentum and power output.

• 한국정밀공학회지
• /
• 제30권8호
• /
• pp.779-784
• /
• 2013

Increased efficiency and improved performance associated with light-weight materials were investigated in this study. Numerous studies have investigated surface treatments to improve the fatigue strength of metals. Laser heat treatment is a promising method because the power and spot size can be easily controlled, allowing a small heat affected zone (HAZ). However, changes in the material properties can result; in particular, the material can become more brittle. In this study, a combination of laser heat treatment and vibration peening was proposed to increase fatigue strength without changing the material characteristics. SCM440H was investigated experimentally, and specimens were tested using a giga-cycle ultrasonic fatigue tester. The results show that the combination of these two processes significantly increased the fatigue strength and, furthermore, different fracture types were observed after a small and large number of cycles.

• 한국멀티미디어학회논문지
• /
• 제18권3호
• /
• pp.298-311
• /
• 2015

Vector data represents a map by its coordinate and Raster data represents a map by its pixel. Since these data types have very large data size, data compression procedure is a compulsory process. This paper compare the results from three different methodologies; GIS (Geographic Information System) vector map data compression using DP(Douglas-Peucker) Simplification algorithm, vector data compression based on Bin classification and the combination between two previous methods. The results shows that the combination between the two methods have the best performance among the three tested methods. The proposed method can achieve 4-9% compression ratio while the other methods show a lower performance.

• 대한한방내과학회지
• /
• 제38권5호
• /
• pp.820-827
• /
• 2017

The prevalence of breast cancer is very high in Korea. Although the patients receive standard treatments, such as surgery, chemotherapy, or radiotherapy, they frequently experience recurrence or metastasis of their tumors. In addition, many patients with breast cancer also suffer from side effect symptoms induced by these standard treatments. Therefore, increasing numbers of patients now want to undergo treatment with traditional Korean medicine (TKM) in addition to conventional treatment. We present a case of 46-year-old female with recurred breast cancer. She first received two kinds of chemotherapy and then underwent surgery. She then also received 4 cycles of adjuvant chemotherapy. At a follow-up examination, she was informed of recurrent lesions on the right anterior chest wall. She started to receive TKM treatments together with a new chemotherapy. After about one month, the size of the recurred tumor in right chest wall had decreased. Her symptoms, such as shoulder pain, chest pain, and nausea induced by conventional therapy, were also improved. We suggest that a combination of TKM and chemotherapy is a promising treatment for breast cancer.

• 지역연구
• /
• 제14권2호
• /
• pp.65-75
• /
• 1998

Education is widely recognized one of main sources for growth. This paper attempts to incorporate the general recognition into formal regional growth model. The model structure is largely neoclassical. It produces a single good with the two factors, educated labor and non-educated labor, via a constant return production migrating to the region with the higher real wage. The educated labor in a region is accumulated by two sources, migration and physical education capital, while the non-educated labor is by only migration. The paper shows that regional growth equilibrium is characterized as a saddle point. This indicates the presence of the minimum threshold size that must be overcome before a region may grow. It contrasts sharply with results obtained in regional growth models. The paper suggests that regional growth is determined less by the technical characteristics of regional production function characteristics of regional production function but by the stock combination of educated function but by the stock combination of education labor and non-educated labor. Based on this result, the impact of agglomeration economies on regional growth is explored. It is by phase diagram demonstrated that the presence of agglomeration economies do not always lead a region to growth since there still exists the minimum threshold even in the presence of agglomeration economies.