• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.6
• /
• pp.568-572
• /
• 2009

We present a ternary microfluidic multiplexer unit, capable to address three flow channels using a pair of control lines with two different threshold pressure valves. The previous binary multiplexer unit addresses only two flow channels using a pair of control line with identical threshold pressure valves, thus addressing $2^{n/2}$ flow channels using n control lines. The present ternary multiplexer addressing three flow channels using a pair of control lines, however, is capable to address $3^{n/2}$ flow channels using n control lines with two different threshold pressure valves. In the experimental study, we characterized the threshold pressure and the response time of the valves used in the ternary multiplexer. From the experimental observation, we also verified that the present ternary multiplexer unit could be operated by two equivalent valve operating conditions: the different static pressures and dynamic pressures at different duty ratio. And then, $3{\times}3$ well array stacking ternary multiplexers in serial is addressed in cross and plus patterns, thus demonstrating the individual flow channel addressing capability of the ternary multiplexer. Thus, the present ternary multiplexer reduces the number of control lines for addressing flow channels, achieving the high well control efficiency required for simple and compact microfluidic systems.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.4 no.3
• /
• pp.400-410
• /
• 2010

In an identity-based threshold broadcast encryption (IDTHBE) scheme, a broadcaster chooses a set of n recipients and a threshold value t, and the plaintext can be recovered only if at least t receivers cooperate. IDTHBE scheme is different from the standard threshold public key encryption schemes, where the set of receivers and the threshold value are decided from the beginning. This kind of scheme has wide applications in ad hoc networks. Previously proposed IDTHBE schemes have ciphertexts which contain at least n elements. In addition, the security of theses schemes relies on the random oracles. In this paper, we introduce two new constructions of IDTHBE for ad hoc networks. Our first scheme achieves S-size private keys while the modified scheme achieves constant size private keys. Both schemes achieve approximately (n-t)-size ciphertexts. Furthermore, we also show that they are provablesecurity under the decision bilinear Diffie-Hellman Exponent (BDHE) assumption in the standard model.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.11
• /
• pp.2597-2615
• /
• 2013

This paper proposes a dynamic downlink load control scheme that jointly employs dynamic load threshold management and virtual coverage management schemes to reduce the degree of performance degradation due to traffic overload in two-tier femtocell networks. With the proposed scheme, the downlink load in a serving macrocell is controlled with a load threshold which is adjusted dynamically depending on the varying downlink load conditions of neighboring macrocells. In addition, traffic overloading is alleviated by virtually adjusting the coverage of the overloaded serving macrocell, based on the adjusted load threshold of the serving macrocell. Simulation results show that the proposed scheme improves the performance of two-tier femtocell networks in terms of the outage probability and sum throughput. This improvement is significantly increased with appropriate values of load thresholds and with an intermediate-level adjustment of the virtual coverage area (i.e., handover hysteresis margin: HOM). Furthermore, the proposed scheme outperforms both a previously proposed load control scheme with a static load threshold and the LTE system without a HOM adjustment.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.21 no.1
• /
• pp.199-205
• /
• 2008

Purpose: This study was conducted for evaluating whether the postpartum women has lower threshold than healthy non delivered women and men. Methods: We divided the groups by three. Group I is consist of postpartum women who have delivered within 7days. Group II is nonparous women, and the Group III is consist of men. Pain threshold in 6 specific points was measured using the digital algometer from each groups. Results: Pain threshold was obviously higher in Group III than Group I, II, And group II’s threshold was significantly higher than group I’s Conclusion: This study shows the postpartum women had lower pressure pain threshold than non delivered women and men. So clinicians should consider the physiologic and psychologic aspects for the pain control if they meet postpartum women.

• Journal of Environmental Science International
• /
• v.20 no.10
• /
• pp.1347-1355
• /
• 2011

In Jeju island, runoff has frequently happened when the rainfall depth is over a threshold value. To simulated this characteristic rainfall-runoff model structure has to be modified. In this study, the TRSM (Threshold Runoff Simulation Method) was developed to overcome the limitations of SWAT in applying to the hydrologic characteristics of Jeju island. When the precipitation and soil water are less than threshold value, we revised the SWAT routine not to make surface/lateral or groundwater discharge. For Hancheon watershed, the threshold value was set as 80% of soil water through the analysis of rainfall-runoff relationship. Through the simulation of test watershed, it was proven that TRSM performed much better in simulating pulse type stream flow for the Hancheon watershed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.31 no.3
• /
• pp.146-151
• /
• 2018

In this study, we compared the threshold-voltage extraction methods of accumulation-type JLDG (junctionless double-gate) MOSFETs (metal-oxide semiconductor field-effect transistors). Threshold voltage is the most basic element of transistor design; therefore, accurate threshold-voltage extraction is the most important factor in integrated-circuit design. For this purpose, analytical potential distributions were obtained and diffusion-drift current equations for these potential distributions were used. There are the ${\phi}_{min}$ method, based on the physical concept; the linear extrapolation method; and the second and third derivative method from the $I_d-V_g$ relation. We observed that the threshold-voltages extracted using the maximum value of TD (third derivatives) and the ${\phi}_{min}$ method were the most reasonable in JLDG MOSFETs. In the case of 20 nm channel length or more, similar results were obtained for other methods, except for the linear extrapolation method. However, when the channel length is below 20 nm, only the ${\phi}_{min}$ method and the TD method reflected the short-channel effect.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.4
• /
• pp.719-724
• /
• 2003

In this paper, we have presented the simulation results about threshold voltage of nano scale lightly doped drain (LDD) MOSFET with halo doping profile. Device size is scaled down from 100nm to 40nm using generalized scaling. We have investigated the threshold voltage for constant field scaling and constant voltage scaling using the Van Dort Quantum Correction Model (QM) and direct tunneling current for each gate oxide thickness. We know that threshold voltage is decreasing in the constant field scaling and increasing in the constant voltage scaling when gate length is reducing, and direct tunneling current is increasing when gate oxide thickness is reducing. To minimize the roll off characteristics for threshold voltage of MOSFET with decreasing channel length, we know $\alpha$ value must be nearly 1 in the generalized scaling.

• The KIPS Transactions:PartA
• /
• v.15A no.5
• /
• pp.243-248
• /
• 2008

This paper proposes a low-power carry look-ahead adder using multi-threshold voltage CMOS. The designed adder is compared with conventional CMOS adder. The propagation delay time is reduced by using low-threshold voltage transistor in the critical path. Also, the power consumption is reduced by using high-threshold voltage transistor in the shortest path. The other logic block is implemented with normal-threshold transistor. Comparing with the conventional CMOS circuit, the proposed circuit is achieved to reduce the power consumption by 14.71% and the power-delay-product by 16.11%. This circuit is designed with Samsung $0.35{\mu}m$ CMOS process. The validity and effectiveness are verified through the HSPICE simulation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.3
• /
• pp.398-403
• /
• 2006

In this paper, we describe a fuzzy threshold selection technique for feature extraction in digital color images. this is achieved by the formulation a fuzzy inference system that evaluates threshold for feature configurations. The system uses two fuzzy measures. They capture desirable characteristics of features such as dependency of local intensity and continuity in an image. We give a graphical description of a nonlinear sketch feature extraction filter and design the fuzzy inference system in terms of the characteristics of the feature. Through the design, we provide selection method on the choice of a threshold to achieve certain characteristics of the extracted features. Experimental results show the usefulness of our fuzzy threshold inference approach which is able to extract features without human intervention.

• Physical Therapy Korea
• /
• v.5 no.2
• /
• pp.1-14
• /
• 1998

This study was conducted to examine the increasing effects of Ga-As-Al laser Koryo-hand acupuncture on experimental pressure threshold. Forty healthy subjects (female=20. male=20) aged 21 to 30 years were randomly assigned to two treatment groups with same ratio in sex. The subjects in the experimental group (n=20) received Ga-As-Al laser stimulation, and those in the control group (n=20) received sham stimulation on appropriate Koryo-hand acupuncture points M10 on the left hand which is reflex point of upper trapezius portion. Experimental pressure threshold at the contralateral upper trapezius was determined with a pressure algometer and Galvanic Skin Response (GSR) before and after treatment. The change of pressure threshold between pretreatment and posttreatment in the experimental group was greater than that in the control group (p<0.05). The result indicates that Ga-As-Al laser Koryo-hand acupuncture increases experimental pressure threshold and suggests that it is an effective noninvasive pain management technique.