• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.45-46
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• 2006

An ultrawide bandpass filter with sharp rejection and wider stopband is designed and implemented using multilayer ceramic configuration. The proposed filter is composed of a broadside coupled structure and a ring type filter with an embedded stripline stub. The measured results show that the fractional bandwidth and upper stopband of the proposed filter are 106 % and better than -30 dB, respectively. The insertion loss is less than 1 dB, and group delay is less than 0.3 ns in the passband. In addition, ring and broadside coupled gap structures are characterized and compared to the proposed structure.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.169-170
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• 2006

A band pass filter for the V-band application with unique circuit and structure was designed and implemented using 2-metals, 3-BCB layers. In the mean while the effective electrical conductivity of metal layer was extracted and its value was $4{\times}10^7S/m$. The insertion loss of band pass filter at 60 GHz was 3.0 dB and group delay was below 0.1 ns.

• Journal of Magnetics
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• v.12 no.1
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• pp.49-52
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• 2007

We investigated annealing effect of microforged powders on magnetic properties and electromagnetic absorption behaviors for ferromagnetic Fe-Cr metal alloy powder-polymer composites. The coercive properties greatly decreased with annealing temperature and the magnetic permeability had significantly increased after microforging and subsequent annealing treatment, due to a reduction in lattice strain of the microforged powders. The power loss in the far field regime also had greatly increased after microforging and subsequent annealing treatment in frequency range from 50 MHz to 6 GHz. As a result, the electromagnetic absorption of ferromagnetic Fe-Cr alloy metal powder-polymer composites was highly improved because of the relaxation of the internal strain during annealing process.

• Journal of Sensor Science and Technology
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• v.28 no.5
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• pp.277-283
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• 2019

In this paper, we propose a distributed fusion estimation for sensor networks using a receding horizon strategy. Communication channels were modelled as Markov jump systems, and a posterior probability distribution for communication channel characteristics was calculated and incorporated into the filter to allow distributed fusion estimation to handle path loss observation situations automatically. To implement distributed fusion estimation, a Kalman-Consensus filter was then used to obtain the average consensus, based on the estimates of sensors randomly distributed across sensor networks. The advantages of the proposed algorithms were then verified using a large-scale sensor network example.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.554-557
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• 2021

Surgeons are increasingly using the right mini-thoracotomy approach to perform aortic valve surgery. This approach has shown better results in terms of blood loss and length of hospital stay than the sternotomy approach. For selected patients requiring aortic root and ascending aorta surgery, a right mini-thoracotomy approach may prove beneficial. In our technique, we placed a 5-cm horizontal skin incision in the right second intercostal space. Femoro-femoral cardiopulmonary bypass was established. A valved aortic conduit was used for aortic root replacement. The patient's postoperative course was uneventful, with a short hospital stay. This technique offers a minimally invasive approach to aortic root and ascending aorta surgery with easy adaptability and reduced costs.

• Clinical Nutrition Research
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• v.12 no.1
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• pp.1-6
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• 2023

Gastrectomy is the most effective method of treating gastric cancer, but it is commonly associated with weight loss, nutritional deficiencies, and the increased risk of malnutrition due to post-surgery complications, including gastric stasis, dumping syndrome, malabsorption, and maldigestion. Malnutrition is a risk factor for postoperative complications and poor prognosis. To prevent it and guarantee a quick recovery after surgery, continuous and individualized nutrition intervention should be performed both before surgery and postoperatively. The Department of Dietetics at Samsung Medical Center (SMC) performed nutritional status assessment before gastrectomy, initial nutritional assessment within 24 hours of admission, description of therapeutic diet after surgery, nutrition counselling before discharge, and nutritional status assessment and individual nutrition counselling after 1, 3, 6, and 12 months from surgery. This is a case report of a patient who underwent gastrectomy as well as intensive nutrition intervention in SMC.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.913-919
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• 2004

Mitochondrial DNA mutations have been reported in recent years in association with sensorineural hering loss. The purpose of this study is to identify the association between the noise-induced sensorineural hearing loss and the A to G mutation at nucleotide 3243, 1555, 7445 of mitochondrial DNA. Study subjects were established by history and chart review, and audiological and clinical data were obtained. Blood was sampled from 214 normal controls, 102 noise-induced hearing loss, and 28 sensorineural hearing loss. The DNA of these individuals were extracted, and mitochondrial DNA fragments were analyzed by polymerase chain reaction. Subsequently, the coding sequence of mitochondrial DNA 3243, 1555, 7445 were sequenced, and compared to the normal sequence, and all sequence variations were analyzed by restriction enzymes. Mitochondrial DNA mutations $(3243A{\rightarrow}G,\;1555A{\rightarrow}4G,\;7445A{\rightarrow}G)$ were not detected by polymerase chain reactions in any patients with noise-induced hearing loss, sensorineural hearing loss, and normal controls. The DNA sequencing of PCR products did not revealed an A to G substitution at nucleotide 3243, 1555, 7445 of mitochondrial DNA. The noise-induced sensorineural hearing loss was not associated with mitochondrial DNA mutation $(3243A{\rightarrow}G,\;1555A{\rightarrow}4G,\;7445A{\rightarrow}G)$.

• International journal of thyroidology
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• v.11 no.2
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• pp.88-91
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• 2018

After introducing tyrosine kinase inhibitors (TKIs) as promising treatments for radioactive iodine refractory advanced thyroid cancer patients, we more often meet patients with TKI-related hormone and electrolyte imbalances in clinics. Hypocalcemia associated with TKI is associated with an imbalance in calcium-vitamin D metabolism. TKI-related hypothyroidism is related to the metabolic rate of thyroid hormones. The two side effects usually occur in the early stages of TKI treatment, and if the imbalance is corrected appropriately, the effects are minor, but in severe cases, the TKI should be discontinued. The authors reported a case of severe hypocalcemia and thyroid dysfunction after TKI treatment. A 56-year-old man suffered from symptomatic hypocalcemia during TKI treatment, which was resolved after he stopped taking the TKI medication. Although calcium and vitamin D replacement have increased, hypocalcemia was recurred and TKI treatments have been permanently stopped due to serious weight loss in grade 3. After the interruption, his calcium levels normalized.

• Tribology and Lubricants
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• v.23 no.6
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• pp.306-311
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• 2007

This paper presents the friction characteristics of pb-fres pin bushing bearings for an automotive gasoline engine. The external load is 100 N to 600 N and the speed of the pin bushing bearing is 1000 rpm to 3000 rpm against the rubbing surfaces. And the contact modes of rubbing surfaces between a piston pin and a pb-free pin bushing specimen are a dry friction, an oil lubricated friction and a mixed friction that is starved by a lack of engine oil. Two influential factors of a contact rubbing modes and a material property are very important parameters on the tribological performance of a friction characteristic between a piston pin and a pb-free pin bushing. The experimental result shows that the pin bushing speed of 2000 rpm shows a typical oil film lubricated sliding contact mode in which means that as the applied load is increased, the friction loss is increasing. But other contact mode depending on the speed and the load may affect to the fiction coefficient without a regular and uniform trend. In summary, the oil lubricated rubbing surface definitely decreases a running-in period in short and increase oil film stiffness, and this may leads the reduction of a friction loss.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.10
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• pp.2233-2238
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• 2013

A novel design method of ultra wideband based on the composite right-/left handed (CRLH) transmission line is presented in this paper. Defected ground structure and microstrip interdigital coupler are used to implement the CRLH transmission line. The proposed CRLH transmission line in this paper have composite characteristics of low pass filter and high pass filter, also it has good advantages of low insertion loss and ultra wide passband characteristics. The structure with different cell number are studied, and the UWB filter using 3-cell CRLH transmission line is fabricated and measured, which shows a good agreement between simulated and measured results. It has center frequency of 5 GHz, fractional bandwidth of 105 %, and insertion loss of 0.7 dB at center frequency.