• Journal of Power System Engineering
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• v.18 no.6
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• pp.45-50
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• 2014

In the previous paper, we have reported on the development of foaming sponge seat with the auxiliary spring member and suggested new possibility of the special seat with the auxiliary plastic member for movie theater chair. In this study, we have examined the major design parameters needed in the development of a foaming sponge seat in which the mesh type plastic member are inserted to improve the vibration transfer effect of a chair seat. Through analyzing several prototypes by applying experimentation as well as the experimental modal analysis method, it was confirmed that the effect of vibration transfer can be improved through the use of a mesh type plastic member and applied to the design of practical chair seat.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.7
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• pp.857-862
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• 2004

HCCI engines take advantage of high compression ratio and heat release rate, they exhibit high efficiency in compression ignition engines. HCCI engines also utilize a lean air/fuel ratio resulting in low emissions of NOx and particulate matter(PM). The objective of this research is to determine the effects of EGR rate on the combustion processes of HCCI. For this purpose, a 4-cylinder, compression ignition engine was converted into a HCCI engine, and a heating device was installed to raise the temperature of the intake air and also to make it more consistent. In addition, a pressure sensor was inserted into each of the cylinders to investigate the differences in characteristics among the cylinders.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.421-422
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• 2019

In this paper, we present the results of the implementation of the strain gauge sensor module which can be applied to measure the load weight in preparation for forklifts with high frequency of safety accidents in the industrial field. The sensor module consisted of strain gauge, LNA, LPF and ADC. In order to increase the accuracy and durability of the sensor, four sensors were inserted into four anchor bolts.

• Journal of Chest Surgery
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• v.54 no.4
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• pp.314-318
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• 2021

In this paper, I present the technique of subxiphoid single-port video-assisted thoracic surgery (VATS) thymectomy for thoracic surgeons to perform this procedure safely. This procedure is indicated for all anterior mediastinal masses and may be extended to lung cancer. The patient is placed in the lithotomy position, and the operator should be on the midline. Below the xiphoid process, a skin incision is made 4-5 cm horizontally at a single thumb's width down. Under two-lung ventilation, CO₂ is insufflated, maintaining 10 mm Hg. The fat tissue and thymic tissue are all resected from the sternum and pericardium between both phrenic nerves using an articulated grasper and an energy device. After retrieval of the mass with a wrap bag, a Jackson-Pratt drain is inserted instead of a chest tube. One of the advantages of this procedure is less postoperative pain than intercostal VATS. The subxiphoid approach can be used for bilateral pneumothorax, bilateral pulmonary metastasectomy, and simple lobectomy for both upper lobes and the right middle lobe.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.14 no.2
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• pp.117-122
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• 2003

Background and Objectives : $VoCoM^{\circledR}$ is a commercialized set composed of prefabricated hydroxylapatite implants and shims of various sizes which are specially designed for the type I thyroplasty. Even though a previously published preliminary report showed that $VoCoM^{\circledR}$ is a convenient and safe product for the type I thyroplasty, further investigations or experiences are yet to be reported. Authors aimed to evaluate the efficacy of $VoCoM^{\circledR}$type I thyroplasty, and its advantage and/or disadvantage. Materials and Method : Twenty three consecutive patients with unilateral vocal cord palsy enrolled for the study, who received type I thyroplasty with $VoCoM^{\circledR}$ between July 2001 and June 2003. Acoustic, aerodynamic and stoboscopic analyses were performed prior to surgery and 1 to 3 months after surgery. Speech language pathologists evaluated their voice quality by GRBAS scale, and patients themselves reported subjective changes of their voice by visual analog scale. Results : The average time for the operation was 80 min, which is about 30 min less than other methods. Preoperative jitter was 3.25$\pm$1.65% and improved to 1.94$\pm$1.79% postoperatively (p<0.05). Preoperative shimmer was 9.72$\pm$6.56% and improved to 5.61 $\pm$3.76% (p<0.05), Maximal phonation time increased from 4.41$\pm$2.99 to 7.98$\pm$4.35 sec (p<0.05) The postoperative stroboscopy revealed an effective medialization in 91.3% of the patients. The subjective phonetic improvements were reported in 21 out of 23 patients. GRBAS scale improved from 2.71$\pm$0.46 to 1.47$\pm$1.12(p<0.05). Additional medialization with $Gore-Tex^{\circledR}$ was easily performed in two revision cases. Previously inserted $VoCoM^{\circledR}$ implant was hard to remove because of the tight integration of soft tissues around the implant. Side effects such as extrusion or foreign body reaction are not observed. $VoCoM^{\circledR}$ was relatively expensive and costed more than 10 times of $Gore-Tex^{\circledR}$. Conclusion : Prefabricated hydroxylapatitie implant($VoCoM^{\circledR}$) provides a convenient, safe and efficient way of vocal fold medialization. However it is relatively expensive and hard to remove.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.582-585
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• 2015

In the aging society, TKRA is steadily increased because of joint diseases. Artificial joint used in TKRA generates metal artifacts in the MRI. Metal artifact may affect diagnosis. In study, We are going to minimize the effect of metal artifact to improve the value of diagnosis by changing the sequence and the type of artificial joint(Co-Cr, Ni-Ti). 1.5T AVANTO, plastic containers and each of the artificial joint (Normal, Co-Cr, NiTi) were used. After the artificial joints fixed in a paper cup was inserted in a plastic container of cylindrical, Signal intensity was measured. To obtain strong and uniform signal intensity, the plastic container was filled with water. We changed Sequences(T1 TSE, T2 TSE, PD TSE) and obtained an Axial image. After excepting the maximum and minimum values, We calculated the average of SNR, CNR and PSNR. Consequently, The SNR, CNR value of PD TSE are measured higher than these of T1 TSE, T2 TSE and The PSNR of Co-Cr is higher than this of Ni-Ti. The SNR of Co-Cr is similar to the SNR of normal comparing this of Ni-Ti. As a result, Using sequence of PD Tse and Co-Cr alloy is considered to be useful.

• Journal of Microbiology and Biotechnology
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• v.3 no.2
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• pp.123-128
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• 1993

The polyesters (polyhydroxyalkanoates; PHAs) production capability in a two-step cultivation of Alcaligenes eutrophus H16(ATCC 17699) was investigated by using various organic carbon sources. The carbon sources used included linear $C_2~C_10$ monocarboxylic acids, $C_3~C_10$ dicarboxylic acids, crotonic acid, and several linear vicinal and $\omega$-diols. The polyesters synthesized were characterized by 500 MHz $^1 H-NMR$ spectroscopy, intrinsic viscosity$[\eta]$ measurement in chloroform and differential scanning calorimetry (DSC). The PHAs synthesis data showed that the use of C-odd ($C_3, C_5, and C_7$) monocarboxylic acids resulted in poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(P(3HB-co-3HV) (3HV content ranging 40 to 70 mol%) while the use of $C_9$ substrate gave the copolyester containing only 4 mol% of 3HV. All culture products obtained on $C_3$~C$_{10}$ dicarboxylic acids gave exclusively P(3HB). 500 MHz $^1 H-NMR$ analysis showed that all polyesters synthesized generally contained 1~2 mol% 3HV even for the unrelated substrates such as the carboxylic acids with even number of carbon. When $\alpha, \omega$-diols with even number of carbon were used as substrates, 4-hydroxybutyrate(4HB) was inserted into the polyester chain composed of P(3HB-co-4HB). Vicinal diols were generally not utilized by the bacterium for polyester production.n.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.1
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• pp.43-53
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• 2007

The purpose of this experimental study was to examine the effect of the decontamination of carbon dioxide ($CO_2$) laser in treatment of ligature-induced peri-implantitis in dogs. A total 24 implants with a sandblasted with large-grit and acid-etched (SLA) surface were inserted in six mongrel dogs. After a 3-month healing period, experimental peri-implantitis characterized by a bone loss of about 3mm was established by inducing with wires. And then wires were removed and plaque control was implemented. Surgical treatment involving flap procedure + debridement of implants surface with chlorhexidine and saline (group 1), flap procedure + GBR with absorbable collagen membrane (Bio-Gide) and mineralized bone graft (Bio-Oss) (group 2), and flap procedure + $CO_2$ laser application + GBR (group 3) was performed. The animals were killed 8 weeks and 16 weeks after treatment, respectively. A histomorphometric analysis confirmed statistically considerable new bone formation within the limit of the 5 most coronal threads in group 3 compared with group 1 at 16 weeks (P<0.05). And intragroup analysis showed considerable increase of new bone formation in group 3 at 16 weeks compared with 8 weeks (P<0.05). The present study demonstrates considerable new bone formation after treatment of experimental peri-implantitis with flap procedure, $CO_2$ laser application and GBR.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.509-516
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• 2004

The measurement of abnormal change of temperature(temperature anomaly) will help determine the safety of various engineering constructions, as the measurement in body often used to diagnose one's health. Temperature anomaly can be occurred in leakage or seepage of water flow in rocks, and in ground water table etc. Grouting materials injected in fractured rocks generate heat during hardening process. The degree of temperature change is associated directly with heat flow characteristics, that is, thermal conductivity, specific heat capacity. density of the surrounding rocks and can afford to assess the grouting efficiency. However, in practice, the use of traditional temperature measuring technique composed of only one single thermal sensor has been fundamentally limited to acquire thermal data sufficient to use for that, partly due to the time-consuming measuring work, partly due to the non-consecutive quality of data. Thus, in this paper, a new concept of temperature measuring technique, what we call, thermal line sensor technique is introduced. In this, the sensors with an accuracy of $0.02^{\circ}$ are inserted at regular intervals in one line cable and addressed by a control device, which enables to fundamentally enhance the capability of data acquisition in time and space. This new technology has been demonstrated on diverse field model experiments. The results were simply meant to be illustrative of a potential to be used for various kinds of temperature measurements encountered in grouting and leakage problems.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.2
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• pp.217-221
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• 2012

As a part of basic research to improve screen quality, which deteriorates when strain occurs within optical sheets in LCD modules for laptop computers, a measurement system is needed to analyze the influence of heat and moisture, which are the main factors causing the strain. It is assumed that the existence of an air gap less of than 0.5 mm inside the LCD module causes humid air from outside to permeate through the module. To investigate this phenomenon, in this study a thin printed circuit board (PCB) of compact sensors that measure temperature and humidity is inserted into LCD modules, and thus, the changes in temperature and humidity can be analyzed in real time. The results can be used as basic data for simulation of the deformation behavior and structural design of LCD modules in the future.