• Journal of Pharmaceutical Investigation
• /
• v.4 no.1_2
• /
• pp.39-45
• /
• 1974

According to previous paper, the hardness of semi-solid as ointments and suppositories causes the tough or skin, the pain and connected with absorption, the state of spread or the efficiency of drug. When the hardening agent or the softening agent is added to ointment whid, is registered on the pharmacopeia of the republic of Korea, the experimertal data by apparent logarithmic hardness are shown is Table 1. The results are as the folloring. 1) In case of the softening agent which is added to ointment base, each has shown two different equation with differnented slope as $K_1$ and $K_2$ value determined (Fig. 1,2). 2) When the hardening agent is added to same ointment base, these studies indicated that there is a direct correlation between $K_1$ and $K_2$. However, in case of softening agent $K_1$ and $K_1$ are not correlated as indicated in Fig. $3{\sim}8$. 3) On condition of same ointment base, the critical poit is proportional to $K_1$ 4) The second effect is at least $3{\sim}17$ times more. sensitive than the first effect or in average 8.3 times more sensitive, Therefore, the results presented in this paper. Suggest that, when the drug is added to a certain ointment base, it should be added within this first effect before the critical point is reached.

• Smart Structures and Systems
• /
• v.18 no.1
• /
• pp.75-92
• /
• 2016

The design of a semi-active (SA) control system addressed to mitigate wind induced structural demand to high wind turbine towers is discussed herein. Actually, the remarkable growth in height of wind turbines in the last decades, for a higher production of electricity, makes this issue pressing than ever. The main objective is limiting bending moment demand by relaxing the base restraint, without increasing the top displacement, so reducing the incidence of harmful "p-delta" effects. A variable restraint at the base, able to modify in real time its mechanical properties according to the instantaneous response of the tower, is proposed. It is made of a smooth hinge with additional elastic stiffness and variable damping respectively given by springs and SA magnetorheological (MR) dampers installed in parallel. The idea has been physically realized at the Denmark Technical University where a 1/20 scale model of a real, one hundred meters tall wind turbine has been assumed as case study for shaking table tests. A special control algorithm has been purposely designed to drive MR dampers. Starting from the results of preliminary laboratory tests, a finite element model of such structure has been calibrated so as to develop several numerical simulations addressed to calibrate the controller, i.e., to achieve as much as possible different, even conflicting, structural goals. The results are definitely encouraging, since the best configuration of the controller leaded to about 80% of reduction of base stress, as well as to about 30% of reduction of top displacement in respect to the fixed base case.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.2
• /
• pp.213-221
• /
• 2011

In this study, we discussed the weight reducing of a urban railway-car body, in particular, of the Korean EMU, by optimizing topology and size of aluminum extrusion profiles. The heaviest parts of aluminum railway-car bodies, i.e., the base plate of underframe and side panels of side frame composed of double skin structures are considered for optimization. Topology optimization process is applied to obtain get an optimized rib structure for the base plate. The thickness of ribs and plates of the topologically optimized base plate and the existing side panel are also optimized by employing the size optimization process. The results are verified by comparing the maximum von Mises stresses and maximum deformation in the case of the existing design with those in the case of the optimized design. It is shown that the weight of a base plate and side panel can be reduced by 12% and that the weight of the whole car body can be reduced by 8.5%.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.6
• /
• pp.2595-2618
• /
• 2018

In this paper, we investigate secure communication with the presence of multiple eavesdroppers (Eves) in a two-tier downlink dense heterogeneous network, wherein there is a macrocell base station (MBS) and multiple femtocell base stations (FBSs). Each base station (BS) has multiple users. And Eves attempt to wiretap a macrocell user (MU). To keep Eves ignorant of the confidential message, we propose a physical-layer security scheme based on cross-layer cooperation to exploit interference in the considered network. Under the constraints on the quality of service (QoS) of other legitimate users and transmit power, the secrecy rate of system can be maximized through jointly optimizing the beamforming vectors of MBS and cooperative FBSs. We explore the problem of maximizing secrecy rate in both non-colluding and colluding Eves scenarios, respectively. Firstly, in non-colluding Eves scenario, we approximate the original non-convex problem into a few semi-definite programs (SDPs) by employing the semi-definite relaxation (SDR) technique and conservative convex approximation under perfect channel state information (CSI) case. Furthermore, we extend the frame to imperfect CSI case and use the Lagrangian dual theory to cope with uncertain constraints on CSI. Secondly, in colluding Eves scenario, we transform the original problem into a two-tier optimization problem equivalently. Among them, the outer layer problem is a single variable optimization problem and can be solved by one-dimensional linear search. While the inner-layer optimization problem is transformed into a convex SDP problem with SDR technique and Charnes-Cooper transformation. In the perfect CSI case of both non-colluding and colluding Eves scenarios, we prove that the relaxation of SDR is tight and analyze the complexity of proposed algorithms. Finally, simulation results validate the effectiveness and robustness of proposed scheme.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.11 no.1
• /
• pp.25-47
• /
• 2007

Background and Purpose: There was seldom study about method that diagnose 8 Constitution beside method of pulse diagnosis in 8 Constitution Medicine. Objectives: This study is to make out check list for 8 Constitution Medicine Diagnosis Expert System Development used CBR(Case based Reasoning). Methods: Review of literatures about special quality element of 8 Constitution and supplement learning advice of 8 Constitution Medicine Experts constructed knowledge base. And then, knowledge base divided through AHP(Analytic Hierarchy Process), and made out check list with this. Results: Knowledge base based on special quality element of 8 Constitution was divided by 5 greate classification and 25 bisection kind, and check list consisted of 251 item was made out through this. Conclusion: Based on this research, cases necessary to make 8 Constitution Medicine Diagnosis Expert System can be gathered through check list, and further study for 8 Constitution Medicine Diagnosis Expert System Development used CBR(Case based Reasoning) is needed to supplement this research.

• Investigative Magnetic Resonance Imaging
• /
• v.21 no.2
• /
• pp.114-118
• /
• 2017

Dermoid cysts are benign congenital tumors composed of keratinizing squamous epithelium and dermal derivatives. They account for less than 1% of all intracranial tumors and are rarely exhibited at the base of the skull. To the best of our knowledge, only one case report has presented computed tomography and conventional T1-weighted magnetic resonance (MR) findings that revealed an infratemporal dermoid cyst. In the present study, we report an unusual case of a dermoid cyst in the right infratemporal fossa, which was incidentally detected by MR imaging with the Dixon technique. This article also highlights the importance of meticulous radiological review and the usefulness of the Dixon technique in everyday clinical practice.

• The Korean Journal of Ecology
• /
• v.23 no.2
• /
• pp.83-88
• /
• 2000

When interpreting change over time in forest ecosystems, distinguishing the effects of forest succession from the effects of environmental stress can be difficult. The result may be a simplistic interpretation. citing a specific successional or environmental cause of forest change when both types may be occurring. We present two case studies of changes in the forest floor in northern hardwoods. First, the belief that 50% of soil organic matter is lost in the first 20 years after logging was based on a study comparing northern hardwood stands of different ages. We resampled a series of 13 such stands after an interval of 15 years, and found that the young stands were not, in fact. losing organic matter as rapidly as predicted from the original chronosequence study. The pattern of higher organic matter content in the forest floors of older stands compared to young stands could be equally well explained by changes in logging practices over the last century as by the aging of the stand. The observed pattern of forest floor organic matter as a function of stand age was previously interpreted as a successional pattern, ignoring changes in treatment history. In the second case study, observed losses of base cations from the forest floor were attributed to cation depletion caused by acid rain and declining calcium deposition. We found that young stands were gaining base cations in the forest floor; losses of base cations were restricted to older stands. Differences in litter chemistry in stands of different ages may explain some of the pattern in cation gains and losses. In this case, the contribution of successional processes to cation loss had been overlooked in favor of environmental stress as the dominant mechanism behind the observed changes. Studies of environmental stress use repeated measures over time. but often don't consider stand age as a factor. Studies of successional change often assume that environmental factors remain constant. We were able to consider both forest succession and external factors because we repeatedly sampled stands of different ages.

• Journal of Korean Society for Atmospheric Environment
• /
• v.21 no.1
• /
• pp.73-81
• /
• 2005

It is widely accepted that, at present, the SO$_2$ emissions in China are not increasing thanks to the rigorous Chinese government policies. However, with the development of western China, it is possible that the SO$_2$ emission amounts might increase in regional scale. In this study, changes of sulfur deposition pattern and unprotected ecosystem in east Asia due to the sulfur emission pattern changes in China are studied by using the RAINS-Asia model. Five scenarios have been postulated to understand the effects on east Asia, especially, on Korea and Japan. It is found that the increase of SO$_2$ emission in western China might increase the total emission in whole China. And the amount of sulfur deposition from western China on east Asia would be higher than those from eastern China. The deposition amount of sulfur species on Asia is 3.2 Mt when SO$_2$ are emitted from western China only while 2.6 Mt from eastern China only. Generally, Korea and Japan are influenced more by emissions from eastern China than western China. However, if the SO$_2$ emissions from western China increase by 100% while those decrease by 10% in eastern China compared to the base case, the deposition amount of sulfur species on Korea and Japan would be higher than the base case. The fraction of unprotected ecosystem in Korea and Japan for the base case are 50 and 5%. However, if the emissions from western China increase by 100% while those decrease by 10% in eastern China, the fraction of unprotected ecosystem in Korea and Japan would be 52 and 6%.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.20 no.2
• /
• pp.148-150
• /
• 2009

Schwannoma are benign, solitary and encapsulated tumors originating from the Schwann cells of the nerve sheath. About 25% to 40% of all schwannomas are found in the head and neck and the acoustic nerve is most frequently involved, but schwannomas of the tongue is rare. When they do occur, treatment is simple. However, diagnosis is invariably delayed because of the vagueness of symptoms. Recently, authors experienced a case of schwannoma occurred in the base of tongue and the tumor was successfully removed through intraoral approach. So we report this case with literature review.

• Proceedings of the KWS Conference
• /
• 2002.10a
• /
• pp.826-830
• /
• 2002

In the civil engineering and architecture fields, welding for large sectional members, such as I section steel and H section steel, are usually performed. a flash welding system, by which large I section steel or H section steel can be welded for a short time, was newly developed. In order to know the basic characteristics of welded joints, the specimens were cut out from flash welded joints, and tensile and fatigue experiments were carried out. The joint efficiency of welded joints by flash welding is 100% for the specimens with reinforcements and 93% for without reinforcements. The fatigue strength of welded joints with reinforcement was about 50% of that of the base metal. Removing the reinforcement generated by flash welding, fatigue strength of flash welded joints became 75% of that of the base metal. In case of flash welded joints with reinforcements, after a couple of fatigue cracks had propagated, ductile fracture occurred at the toe. In flash welded joints without reinforcements, fracture occurred at the bond or at HAZ (Heat Affected Zone). In case of fracture at the bond, fracture was brittle, and in case at HAZ, fracture was ductile.