• Mass Spectrometry Letters
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• v.10 no.1
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• pp.27-31
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• 2019

In this article, the properties of ${CO_2}^+(CO_2)_n$ clusters in a Paul ion trap have been investigated using mass-selective instability mode which conducted by chosen precursor ions, mainly $Ar^+$ and ${CO_2}^+$ produced by a mixture of Ar and $CO_2$. Exposure of ${CO_2}^+$ ions to $CO_2$ molecules, lead to the formation of ${CO_2}^+(CO_2)_n$ clusters. Here, Ar gas react as a buffer gas and lead to form ${CO_2}^+(CO_2)_n$ cluster by collisional effect.

• Journal of Korean Neurosurgical Society
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• v.42 no.3
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• pp.184-190
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• 2007

Objective : The authors retrospectively analyzed clinical and radiographic features of patients who developed symptomatic adjacent segment degeneration (ASD) that required re-operation. Methods : From 1995 to 2004, among 412 patients who underwent posterior lumbar fusion surgery, the authors experienced twenty-six patients who presented symptomatic ASD. Records of these patients were reviewed to collect clinical data at the first and second operations. Results : The patients were 9 males and 17 females whose mean age was $63.5{\pm}8.7$ years. Among 319 one segment and 102 multi-segment fusions, 16 and 10 patients presented ASD, respectively. Seventeen ASDs were noticed at the cephalad to fusion (65%), eight at the caudad (31%), and one at the cephalad and caudad, simultaneously (4%). All patients underwent decompression surgery. Nine patients underwent additional fusion surgeries to adjacent degenerated segments. In 17 patients who underwent only decompression surgery without fusion, the success rate was 82.4%. In fusion cases. the success rate was observed as 55.5%. There were no statistically significant factors to be related to development of ASD. However, in cases of multi-level fusion surgery, there was a tendency toward increasing ASD. Conclusion : Multi-segment fusion surgery could be associated with a development of ASD. In surgical treatment of symptomatic ASD, selective decompression without fusion may need to be considered as a primary procedure, which could reduce the potential risk of later occurrence of the other adjacent segment disease.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1284-1290
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• 2001

Objective : PCB cervical instrument is a newly introduced fusion device which comprises cervical plate, cage (spacer) and screw system. It is developed to enhance fusion rate and stability, as well as to reduce complications related to hardware failure. We investigated the efficacy of clinical and radiological results of PCB instrument and Lubboc bone. Methods : From August, 1998 to October, 1999, authors performed 54 cases of anterior cervical interbody fusion with PCB instrument and Lubboc bone. Retrospective analysis was undertaken based on clinical and radiological findings. Clinical improvement was evaluated according to Odom's criteria. Cervical plain films and tomography were taken every 2 months to evaluate the degree of interbody fusion and disc height changes. Results : Bone fusion was observed in 36 cases(90%) over 6 months after operation, and during which time there was no significant interval change. There were 3 cases of hardware dislodgement. Disc height was increased significantly and preserved in all cases. Clinical outcome over good degree was seen more than 94% of patients. Conclusion : Longer follow-up period and comparative studies to similar instrument appear to be necessary, but this instrumentation system has shown high fusion rate and fewer adverse effects in our series. We believe this system might be indicated for the treatment of cervical trauma and degenerative disease in selective cases.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.1
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• pp.189-196
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• 2024

Frequent false positives alarm from the Intelligent Selective Control System have raised significant concerns. These persistent issues have led to declines in operational efficiency and market credibility among agents. Developing a new model or replacing the existing one to mitigate false positives alarm entails substantial opportunity costs; hence, improving the quality of the training dataset is pragmatic. However, smaller organizations face challenges with inadequate capabilities in dataset collection and refinement. This paper proposes an automatic human pose data collection system centered around a human pose estimation model, utilizing camera-based sensor fusion techniques and edge devices. The system facilitates the direct collection and real-time processing of field data at the network periphery, distributing the computational load that typically centralizes. Additionally, by directly labeling field data, it aids in constructing new training datasets.

• KSBB Journal
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• v.16 no.1
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• pp.1-10
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• 2001

Escherichia coli has been used as an expression work horse for foreign genes. This article summarized recent development in genetic engineering techniques for overproduction of medical proteins and industrial enzymes. Special emphasis was placed upon research activities concerning folding and refolding of inclusion bodies at genetic and fermentation levels. Plasmid and mRNA stabilization, development of strong inducible promoters, modification of translational elements and reduction of rpoteolytic degradation were carried out to elevate an expression level of a target protein. Optimization of culture conditions, improvement of denaturation and renaturation steps and coexpression of molecular chaperones or foldase were accomplished to produce active proteins in soluble form. Fusion protein systems with selective separation and surface display technology were also performed in an effort to make the E. coli expression system more effective and versatile.

• Molecules and Cells
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• v.41 no.1
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• pp.18-26
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• 2018

Mitochondrial quality control systems are essential for the maintenance of functional mitochondria. At the organelle level, they include mitochondrial biogenesis, fusion and fission, to compensate for mitochondrial function, and mitophagy, for degrading damaged mitochondria. Specifically, in mitophagy, the target mitochondria are recognized by the autophagosomes and delivered to the lysosome for degradation. In this review, we describe the mechanisms of mitophagy and the factors that play an important role in this process. In particular, we focus on the roles of mitophagy adapters and receptors in the recognition of damaged mitochondria by autophagosomes. In addition, we also address a functional association of mitophagy with mitochondrial dynamics through the interaction of mitophagy adaptor and receptor proteins with mitochondrial fusion and fission proteins.

• ETRI Journal
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• v.34 no.2
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• pp.216-225
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• 2012

This paper presents a transceiver module for human body communications whereby a spread signal with a group of 64 Walsh codes is directly transferred through a human body at a chip rate of 32 Mcps. Frequency selective digital transmission moves the signal spectrum over 5 MHz without continuous frequency modulation and increases the immunity to induced interference by the processing gain. A simple receiver structure with no additional analog circuitry for the transmitter has been developed and has a sensitivity of 250 ${\mu}V_{pp}$. The high sensitivity of the receiver makes it possible to communicate between mobile devices using a human body as the transmission medium. It enables half-duplex communication of 2 Mbps within an operating range of up to 170 cm between the ultra-mobile PCs held between fingertips of each hand with a packet error rate of lower than $10^{-6}$. The transceiver module consumes 59 mA with a 3.3 V power supply.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.3
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• pp.195-203
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• 2020

Selective laser melting(SLM) is one of the powder bed fusion(PBF) processes, which enables quicker production of nearly fully dense metal parts with a complex geometry at a moderate cost. However, the process still lacks knowledge and the experimental evaluation of possible process parameter sets is costly. Thus, this study presents a finite element analysis model of the SLM process to predict the melt pool characteristics. The physical phenomena including the phase transformation and the degree of consolidation are considered in the model with the effective method to model the volume shrinkage and the evaporated material removal. The proposed model is used to predict the melt pool dimensions and validated with the experimental results from single track scanning process of Ti-6Al-4V. The analysis result agrees with the measured data with a reasonable accuracy and the result is then used to evaluated each of the process parameter set.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.5
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• pp.239-244
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• 2019

Traditional casting methods require long production lead time and high cost while not accommodating design changes easily. One of the technological alternatives to improve casting method to meet diversifying needs is Additive Manufacturing (AM). Among the 7 AM techniques, Powder Bed Fusion (PBF) is deemed most appropriate for casting applications. Currently, most AM machines are imported; therefore limiting the scope of available services and applications. This paper explores the domestic development of AM machines as well as the applications in casting. Each chapter describes development phases of PBF machines, applicable materials and parameter settings, while the last chapter illustrates a successful case of additive manufacturing industrial casting cores.

• Journal of Korean Neurosurgical Society
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• v.51 no.4
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• pp.203-207
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• 2012

Objective: The purpose of this prospective study was to evaluate the efficacy and safety of screw fixation without bone fusion for unstable thoracolumbar and lumbar burst fracture. Methods: Nine patients younger than 40 years underwent screw fixation without bone fusion, following postural reduction using a soft roll at the involved vertebra, in cases of burst fracture. Their motor power was intact in spite of severe canal compromise. The surgical procedure included postural reduction for 3 days and screw fixations at one level above, one level below and at the fractured level itself. The patients underwent removal of implants 12 months after the initial operation, due to possibility of implant failure. Imaging and clinical findings, including canal encroachment, vertebral height, clinical outcome, and complications were analyzed. Results: Prior to surgery, the mean pain score (visual analogue scale) was 8.2, which decreased to 2.2 at 12 months after screw fixation. None of the patients complained of worsening of pain during 6 months after implant removal. All patients were graded as having excellent or good outcomes at 6 months after implant removal. The proportion of canal compromise at the fractured level improved from 55% to 35% at 12 months after surgery. The mean preoperative vertebral height loss was 45.3%, which improved to 20.6% at 6 months after implant removal. There were no neurological deficits related to neural injury. The improved vertebral height and canal compromise were maintained at 6 months after implant removal. Conclusion: Short segment pedicle screw fixation, including fractured level itself, without bone fusion following postural reduction can be an effective and safe operative technique in the management of selected young patients suffering from unstable burst fracture.