• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.46 no.3
• /
• pp.34-41
• /
• 2009

This paper investigates the issue of efficient reading for sensor data of semi-passive sensor tag. The Cold Chain management system requires complete sensor data without data loss and the short processing time of reading sensor tag data. However, reading the sensed data could be interfered by RF environment such as a jamming, obstacle and so on. This study found that it could lead to loss of the sensed data and takes much time to read it when data loss is occurred. To solve this problem, we propose the transaction processing mechanism that guarantees efficient reading of the sensed data. To do this, we present the technique of dynamic packet size and technique of data recovery to execute read transaction. These techniques improve the reliability of reading operation as well as speed up of read process for the large capacity data. This paper contributes to the improvement of efficient reading of sensed data without any loss of data and large time required.

• Biomolecules & Therapeutics
• /
• v.22 no.1
• /
• pp.27-34
• /
• 2014

Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin $D_2$ ($PGD_2$) and 5-lipoxygenase (5-LO) dependent leukotriene $C_4$ ($LTC_4$) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular $Ca^{2+}$ influx via phospholipase $C{\gamma}1$ ($PLC{\gamma}1$) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-${\kappa}B$ (NF-${\kappa}B$) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum $LTC_4$, $PGD_2$, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.

• Archives of Plastic Surgery
• /
• v.39 no.4
• /
• pp.317-321
• /
• 2012

Background Many topical hemostatics are widely applied for bleeding control. They can be classified into two categories according to their mechanism of action on the clotting cascade in a biologically active or passive manner. Passive hemostatics include cellulose and gelatin. We performed an experimental study to compare the effect of passive hemostatics in wound healing by applying them to a rectus abdominis muscle defect of white mice. Methods Surgicel is a sterile absorbable knitted fabric prepared by the controlled oxidation of regenerated cellulose. Spongostan is an absorbable hemostatic gelatin sponge. In 30 mice, a $1{\times}1$ cm defect was created on the rectus abdominis muscle and the materials were applied in three ways: control group, cellulose (Surgicel) group, gelatin (Spongostan) group. For the histologic analysis, biopsies were performed at 3 and 28 days. Results After 3 days, the cellulose group showed limited granulation formation with acute inflammatory reactions similar to the control group. At the 28th day, moderate amounts of granulation tissue formation was observed with milder inflammatory reactions than the control group. In the gelatin group, after 3 days, gelatin remnants were observed surrounded by severe inflammatory changes. After 28 days, the same quantity of gelatin remnants could be still observed. Conclusions This study suggests that cellulose is associated with minimal morbidity in wound healing, while the use of gelatin shows severe adverse tissue reactions with delayed wound healing. Consequently, cellulose is better than gelatin when considering wound healing.

• The Journal of Korean Medicine
• /
• v.18 no.1
• /
• pp.25-39
• /
• 1997

Shoulder hand syndrome is characterized by pain, vasomotor instability, and tenderness, mainly in the distal upper extremity. The pathophysiologic mechanism of this syndrome is not yet proved. The purpose of this study is to evaluate the usefulness of thermographic imaging on shoulder hand syndrome after stroke for early diagnosis and its clinical pattern analysis including acupuncture and electroacupuncture therapy. This study was performed from June to September in 1996 on 46 stroke patients who were admitted at Oriental hospital of Kyung Hee Medical Center. The study group were 23 patients with shoulder hand syndrome. The control group were 23 patients without shoulder hand syndrome. Skin temperatures on the both upper extremities were measured by Digital Infrared Thermographic Imaging(D.I.T.I.) before the study and 3 weeks later again. The results were as follows; 1. The shoulder hand syndrome group were significantly more restricted in shoulder passive range of motion than the control group. 2. The shoulder hand syndrome group showed significant temperature difference of both dorsal hands. 3. The electroacupunture therapy group were significantly more improved on the temperature difference of both dorsal hands than acupuncture therapy group in 3 weeks later. 4. Both posterior arms showed the biggest temperature difference from 11 to 30 days in shoulder hand syndrome group. 5. The lesser passive ROM(range of motion) of shoulder group showed significantly increased temperature difference of both hands. The above results show that measurement of shoulder passive range of motion and D.I.T.I. is a useful method for early diagnosis on shoulder hand syndrome and its clinical pattern analysis including evaluation of acupuncture and electroacupuncture therapy. Continuous study will be needed for more clinical application and evaluation on shoulder hand syndrome.

• Journal of the Korean Chemical Society
• /
• v.60 no.3
• /
• pp.169-176
• /
• 2016

In a borate buffer solution, the growth kinetics and the electronic properties of passive film on aluminum were investigated, using the potentiodynamic method, chronoamperometry, and multi-frequency electrochemical impedance spectroscopy. The corrosion of aluminum was heavily influenced by the degree of oxygen concentration because of the increasing reduction current. The oxide film formed during the passivation process of aluminum has showed the electronic properties of n-type semiconductor, which follow from the Mott-Schottky equation. It was found out that the passive film (Al(OH)₃) of Al formed in the low electrode potential changes to Al₂O₃ while the electrode potential increases. The growth kinetics data as measured by chronoamperometry suggests a mechanism in which the growth of the film of Al₂O₃ is determined by field-assisted transport of ions through the film.

• Journal of Pharmaceutical Investigation
• /
• v.34 no.6
• /
• pp.491-497
• /
• 2004

We investigated some important factors which affect the transdermal flux of ketoprofen, a nonsteroidal anti-inflammatory agent, as a first step to provide some basic knowledge for the development of a iontophoretic transdermal patch system. Factors such as current density, polarity, buffer (HEPES) and electrolyte concentration and pH were studied using hairless mouse skin. The effect of poly(L-lysin), which is known to affect the electro-osmotic flow through skin, on flux was also studied. Passive flux was about $20\;{\mu}g/cm^2hr$ at pH 4.0, but was negligible at pH 7.4 where all ketoprofen molecules dissolved are ionized (ketoprofen pKa=5.94). At pH 4.0, application of anodal current increased the flux further above the passive level, however anodal flux at pH 7.4 was much smaller than passive flux at pH 4.0. The application of cathodal current at pH 4.0 increased the average flux to $30-40\;{\mu}g/cm^2hr$, depending on the current density applied. At pH 7.4, cathodal flux was only about $5\;{\mu}g/cm^2hr$. Decrease in buffer and electrolyte concentration increased this cathodal flux about 10 fold. However decrease in HEPES buffer concentration 100 fold did not affect the flux. Anodal flux of acetaminophen was much larger than cathodal flux, indicating that electroosmotic flow can be playing an important role in the flux. Poly(L-lysin) increased the cathodal flux at pH 7.4. These results provide some important insights into the mechanism of transdermal flux of ketoprofen and the role of electroosmotic flow.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.45 no.1
• /
• pp.28-45
• /
• 2021

The importance of smart clothing as a product is increasingly emphasized as further growth in the potential of the smart market is expected. There is a high understanding and sympathy for the potential of smart clothing in the mass consumer market; therefore, commercialization is not actively carried out. This study enhances the understanding of the development direction of products with a focus on technical benefits, in order for smart clothing to gain access to customers as wearable devices. This study identifies major technologies used in smart clothing through an analysis of the patent technology status of smart clothing in Korea. Smart clothing is divided into three types: passive smart, active smart and advanced smart clothing based on a reaction mechanism and functional scope. We present the smart clothing and discuss the product features for three types. According to research, smart clothing products were equipped with passive, active, and advanced smart systems as well as provided new services by converging big data and AI technologies, rather than only using technologies such as sensors, controls, and actuators. Future directions for new smart clothing product development is also discussed in the conclusion.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.2
• /
• pp.178-184
• /
• 2012

This paper presents a transformable track mechanism for wall climbing robots. The proposed mechanism allows a wall climbing robot to go over obstacles by transforming the track shape, and also increases contact area between track and wall surface for safe attachment. The track mechanism is realized using a timing belt track with one driving actuator. The inner frame of the track consists of serially connected 5R-joints and 1P-joint, and all joints of the inner frame are passively operated by springs, so the mechanism does not require any actuators and complex control algorithms to change its shape. Static analysis is carried out to determine design parameters which enable $90^{\circ}$ wall-to-wall transition and driving over projected obstacles on wall surfaces. A Prototype is manufactured using the transformable track on which polymer magnets are installed for adhesion force. The size of the prototype is $628mm{\times}200mm{\times}150mm$ ($Length{\times}Width{\times}Height$) and weight is 4kgf. Experiments are performed to verify its climbing capability focusing on $90^{\circ}$ wall to wall transition and driving over projected obstacle.

• Nuclear Engineering and Technology
• /
• v.49 no.1
• /
• pp.54-70
• /
• 2017

The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility-the advanced core-cooling mechanism experiment (ACME)-was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups-a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break-were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient.

• Journal of KIISE:Computing Practices and Letters
• /
• v.9 no.1
• /
• pp.100-108
• /
• 2003

By choosing Multicast for transmission of educational contents in the Remote Educational System, we can reduce the server load and increase network bandwidth utilization. We design and implement Multicast Middleware for the Remote Educational System in this paper. There are three characteristics in this Multicast Middleware: 1) Through Centralized Multicast Group Management for passive members, it allows a host to make multicast group, which is composed of receivers, called Group Member and who are chosen by the host, called group Maker. Because, all groups are created by the Group Maker in Centralized Group Management, Group Member's join action will be passive 2) Maintenance and recovery of multicast group information in order to restore from exception and crash; the maintenance and recovery mechanism of Group Maker is distinct from that of Group Member. 3) The mechanism which enables to transmit large size multimedia data through multicasting and remove additional copy operation through shared buffer. Fragmentation/de-fragmentation for large data delivery results in additional copy operation in user level. But by using user level shared buffer, it can be done without user Bevel copy operation. By applying to Remote Educational environment which consists of 30 PCs and Fast Ethernet, we can examine the efficiency of this middleware, which can transmit 18frames/sec movie which resolution 320 $\times$ 120 pixels, 128Kbps encoded sound data and some text data.