• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.455-462
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• 2001

We propose a new method to evaluate the network reliability which greatly reduces the intermediate steps toward calculations of maximum capacity flow by excluding unnecessary simple paths contained in the set of failure simple paths. By using signed simple paths and signed flow, we show that our method is more efficient than that of Lee and Park (2001a) in the number of generated composite paths and in the procedure for obtaining minimal success composite paths. Numerical examples are given to illustrate the use and the efficiency of the method.

• Communications for Statistical Applications and Methods
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• v.13 no.3
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• pp.577-585
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• 2006

This paper presents a method for reliability evaluation of a telecommunication network with variable link-capacities when the simple paths of the network are known. The LP-EM, suggested by Lee and Park (2001), identifies a composite path as a subnetwork and adds only a minimal set of links at each step which gives maximal increase on the maximum capacity flow of the subnetwork. Thereby the LP-EM reduces the possible occurrence of redundant composite paths significantly over other existing methods. Based on the LP-EM, our method further reduces the possible redundancy by identifying such simple paths that could give no increase of maximum capacity flow on the current subnetwork and excluding those simple paths from consideration in the process of constructing composite paths.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.343-347
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• 1992

In this paper, an unilateral teleoperation system using an universal master arm is developed. This system is composed of an universal master arm, a slave arm and a telerobot controller. The universal master arm has a vertically articulated type link structure, while an industrial robot is used as a slave arm. As the shapes of master arm and slave arm are different, the workspace mapping is needed, which maps the workspace of master arm to that of slave arm. Experimental results show that the slave arm of the developed system effectively follows the operator's motion.

• Molecules and Cells
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• v.41 no.8
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• pp.742-752
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• 2018

Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive degeneration of dopaminergic (DAergic) neurons, particularly in the substantia nigra (SN). Although circadian dysfunction has been suggested as one of the pathophysiological risk factors for PD, the exact molecular link between the circadian clock and PD remains largely unclear. We have recently demonstrated that $REV-ERB{\alpha}$, a circadian nuclear receptor, serves as a key molecular link between the circadian and DAergic systems. It competitively cooperates with NURR1, another nuclear receptor required for the optimal development and function of DA neurons, to control DAergic gene transcription. Considering our previous findings, we hypothesize that $REV-ERB{\alpha}$ may have a role in the onset and/or progression of PD. In the present study, we therefore aimed to elucidate whether genetic abrogation of $REV-ERB{\alpha}$ affects PD-related phenotypes in a mouse model of PD produced by a unilateral injection of 6-hydroxydopamine (6-OHDA) into the dorsal striatum. $REV-ERB{\alpha}$ deficiency significantly exacerbated 6-OHDA-induced motor deficits as well as DAergic neuronal loss in the vertebral midbrain including the SN and the ventral tegmental area. The exacerbated DAergic degeneration likely involves neuroinflammation-mediated neurotoxicity. The $REV-erb{\alpha}$ knockout mice showed prolonged microglial activation in the SN along with the over-production of interleukin $1{\beta}$, a pro-inflammatory cytokine, in response to 6-OHDA. In conclusion, the present study demonstrates for the first time that genetic abrogation of $REV-ERB{\alpha}$ can increase vulnerability of DAergic neurons to neurotoxic insults, such as 6-OHDA, thereby implying that its normal function may be beneficial for maintaining DAergic neuron populations during PD progression.

• Journal of Oral Medicine and Pain
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• v.48 no.3
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• pp.106-111
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• 2023

Purpose: In this study, we evaluate the potential of the relative ratio of capsular width (RCW) between the affected side (Aff) and non-affected side (Non-aff) in patients with temporomandibular joint (TMJ) arthralgia. We assessed whether RCW may hold greater diagnostic significance than the objective capsular width (CW) reported in previous studies when diagnosing arthralgia using ultrasonography (US). Methods: Forty-nine patients were assessed using US, excluding four patients with bilateral arthralgia. The patients were divided into two groups: 40 with unilateral arthralgia (UA), and nine without arthralgia (NA). We measured CW and masseter muscle thickness using US. Moreover, we employed RCW to analyze the variances between the groups. The numerical rating scale (NRS) and RCW were compared before and after dexamethasone injection in 10 patients who underwent follow-up evaluations. Results: Within the UA group, CW on the Aff was found to be significantly larger compared to the Non-aff (p<0.001). Additionally, RCW in the UA group was greater than that in the NA group (p<0.01). Furthermore, after dexamethasone injection, a reduction in the NRS and RCW values was observed in the 10 patients who were followed up. Conclusions: While previous studies have suggested a link between arthralgia and TMJ effusion, making CW a possible indirect diagnostic indicator for arthralgia, our findings propose that RCW could hold more diagnostic value than objective CW. However, additional studies are required to standardize the protocols for interpreting US results and determining the cutoff value of RCW in diagnosing TMJ arthralgia.