• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.1
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• pp.79-85
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• 1998

Changes in the human voice occur between infancy and old age and reflect a myriad of biological changes that influence the size, shape, and physical properties of the larynx. The human larynx is located near the base of the neck and attached inferiorly to the trachea and opens superiorly into the pharynx. The larynx by the third month of fetal life has the same features recognizable at birth. The fundamental frequency of vocal fold vibration generally becomes higher in early age, lower in middle age, and higher in old age. These decreases in Fo undoubtedly result from a combination of factors, consisting of modest increase in length and mass of the muscle and connective tissues of the vocal fold. But the level of the larynx in the neck may be closely connected with Fo directly, high larynx in related with high pitch and low larynx with low pitch. The purpose of this study is to determine the developmental level difference from child to adult larynx using conventional radiography, and the change of speaking fundamental frequency from second decade to sixth decade.

• Smart Structures and Systems
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• v.18 no.3
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• pp.449-470
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• 2016

Energy harvesting is an emerging technique that extracts energy from surrounding environments to power low-power devices. For example, it can potentially provide sustainable energy for wireless sensing networks (WSNs) or structural control systems in civil engineering applications. This paper presents a comprehensive study on harvesting energy from earthquake-induced structural vibrations, which is typically of low frequency, to power WSNs. A macroscale pendulum-type electromagnetic harvester (MPEH) is proposed, analyzed and experimentally validated. The presented predictive model describes output power dependence with mass, efficiency and the power spectral density of base acceleration, providing a simple tool to estimate harvested energy. A series of shaking table tests in which a single-storey steel frame model equipped with a MPEH has been carried out under earthquake excitations. Three types of energy harvesting circuits, namely, a resistor circuit, a standard energy harvesting circuit (SEHC) and a voltage-mode controlled buck-boost converter were used for comparative study. In ideal cases, i.e., resistor circuit cases, the maximum electric energy of 8.72 J was harvested with the efficiency of 35.3%. In practical cases, the maximum electric energy of 4.67 J was extracted via the buck-boost converter under the same conditions. The predictive model on output power and harvested energy has been validated by the test data.

• Structural Engineering and Mechanics
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• v.64 no.2
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• pp.233-241
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• 2017

Earlier numerous studies have been done on implementation of Tuned Liquid Damper (TLD) for structural vibration control by many researchers. As per current review there is no significant study on a sloped bottom TLD. TLD's are passive devices. A TLD is a tank rigidly attached to the structure and filled partially by liquid. When fundamental linear sloshing frequency is tuned to structure's natural frequency large sloshing amplitude is expected. In this study set of experiments are conducted on flat bottom and sloped bottom TLD at beach slope $20^{\circ}$, $30^{\circ}$ and $45^{\circ}$, for different types of structures, mass ratio, and depth ratio to investigate the overall effectiveness of TLD and specific effect of TLD parameters on structural response. This experimental study shows that a properly designed TLD reduces structural response. It is also observed that effectiveness of TLD increases with increase in mass ratio. In this experimental study an effectiveness of sloped bottom TLD with beach slope $30^{\circ}$ is investigated and compared with that of flat bottom TLD in reducing the structural response. It is observed from this study that efficiency of sloped bottom TLD in reducing the response of structure is more as compared to that of flat bottom TLD. It is shown that there is good agreement between numerical simulation of flat bottom and sloped bottom TLD and its experimental results. Also an attempt has been made to investigate the effectiveness of sloped bottom TLD with beach slope $20^{\circ}$ and $45^{\circ}$.

• Biomedical Engineering Letters
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• v.8 no.4
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• pp.365-371
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• 2018

Uninterrupted monitoring of multiple subjects is required for mass causality events, in hospital environment or for sports by medical technicians or physicians. Movement of subjects under monitoring requires such system to be wireless, sometimes demands multiple transmitters and a receiver as a base station and monitored parameter must not be corrupted by any noise before further diagnosis. A Bluetooth Piconet network is visualized, where each subject carries a Bluetooth transmitter module that acquires vital sign continuously and relays to Bluetooth enabled device where, further signal processing is done. In this paper, a wireless network is realized to capture ECG of two subjects performing different activities like cycling, jogging, staircase climbing at 100 Hz frequency using prototyped Bluetooth module. The paper demonstrates removal of baseline drift using Fast Fourier Transform and Inverse Fast Fourier Transform and removal of high frequency noise using moving average and S-Golay algorithm. Experimental results highlight the efficacy of the proposed work to monitor any vital sign parameters of multiple subjects simultaneously. The importance of removing baseline drift before high frequency noise removal is shown using experimental results. It is possible to use Bluetooth Piconet frame work to capture ECG simultaneously for more than two subjects. For the applications where there will be larger body movement, baseline drift removal is a major concern and hence along with wireless transmission issues, baseline drift removal before high frequency noise removal is necessary for further feature extraction.

• The Korean Journal of Nuclear Medicine
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• v.27 no.2
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• pp.183-190
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• 1993

Abnomalities in the embryologic development and migration of the thyroid gland can result in ectopic thyroid tissue, which may occur on the midline in any position from the base of the tongue to the mediastinum. Although ectopic thyroid may be asymptomatic, local obstructive, hemorrhagic or other complication may occur. Radinuclide thyroid scan is confirmatory when the diagnosis is suspected. Hypothyroidism is common in lingual thyroid, and thyroid supplementation is generally required. In order to evaluate the features of ectopic thyroid, we investigated the scintigraphic findings, thyroid function test and clinical symptoms of 19 patients with ectopic thyroid. 1) Th frequency of ectopic thyroid was about 5.3 times more common in female than in male. Then patients were mostly below 30 years old (79%). 2) The frequency of location of ectopic thyroid were as follows: 10 cases in the tongue base, 1 case in suprahyoid, 5 cases in infrahyoid and 3 cases over 2 areas. 3) The thyroid function test was done in 16 cases of the ectopic thyroid patients. The hypothyroidism was detected in 7 cases, subclinical hypothyroidism in 4 cases and normal thyroid function in 5 cases. 4) The rate of hypothyroidism is 90% in the lingual thyroid and 33% in the others. The thyroid dysfunction was related with the location of the ectopic thyroid (p < 0.05). 5) The clinical manifestations include a mass in the tongue base, the foreignbody sensation of a throat and a swallowing difficulty in lingual thyroid. The palpable mass was the chief complaint in the others. 6) We prescribed the thyroid hormone to 10 cases with hypothyroidism. The ectopic thyroid was removed in 2 cases with normal thyroid function. The rest is following up through OPD. We must consider the possibility of the ectopic thyroid and take the thyroid scan when the patient has a mass in the tongue base, the sublingual and the prelaryngeal area. Then we have to check the thyroid function and follow up when the ectopic thyroid is diagnosed, because the patient with normal thyroid function can result in the hypothyroidism. Except these, we must mind of the possibility of occurence of the cancer in the ectopic thyroid tissue.

• Preventive Nutrition and Food Science
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• v.21 no.2
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• pp.104-109
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• 2016

In the current study, we investigated the longitudinal association between dietary acid load and the risk of insulin resistance (IR) in the Tehranian adult population. This longitudinal study was conducted on 925 participants, aged 22~80 years old, in the framework of the third (2006~2008) and fourth (2009~2011) phases of the Tehran Lipid and Glucose Study. At baseline, the dietary intake of subjects was assessed using a validated semi-quantitative food frequency questionnaire, and the potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores were calculated at baseline. Fasting serum insulin and glucose were measured at baseline and again after a 3-year of follow-up; IR was defined according to optimal cut-off values. Multiple logistic regression models were used to estimate the risk of IR according to the PRAL and NEAP quartile categories. Mean age and body mass index of the participants were 40.3 years old of $26.4kg/m^2$, respectively. Mean PRAL and NEAP scores were -11.2 and 35.6 mEq/d, respectively. After adjustment for potential confounders, compared to the lowest quartile of PRAL and NEAP, the highest quartile was accompanied with increased risk of IR [odds ratio (OR)=2.81, 95% confidence interval (CI)=1.32~5.97 and OR=2.18, 95% CI=1.03~4.61, respectively]. Our findings suggest that higher acidic dietary acid-base load, defined by higher PRAL and NEAP scores, may be a risk factor for the development of IR and related metabolic disorders.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.587-592
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• 2002

A new digital correlator fur an airborne synthetic aperture radiometer was designed in order to replace the conventional analog correlator unit which will become very complicated while the number of channels is increasing. The digital correlator uses digital IQ demodulator instead of the intermediate frequency (IF) phase shifter to make the correlation processing performed digitally at base band instead of analogly at IF. This technique has been applied to the digital receiver in softradio. The down-converted IF signals from each pair of receiver channels become low rate base-band digital signals after under-sampled, Digitally Down-Converted (DDC), decimated and filtered by FIR filters. The digital signals are further processed by two digital multipliers (complex correlation), the products are integrated by the integrators and finally the outputs from the integrators compose of the real part and the imaginary part of a sample of the visibility function. This design is tested by comparing the results from digital correlators and that from analog correlators. They are agreed with each other very well. Due to the fact that the digital correlators are realized with the help of Analog-Digital Converter (ADC) chips and the FPGA technology, the realized volume, mass, power consumption and complexity turned out to be greatly reduced compared with that of the analog correlators. Simulations show that the resolution of ADC has an influence on the synthesized antenna patterns, but this can be neglected if more than 2bit is used.

• Earthquakes and Structures
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• v.20 no.1
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• pp.55-70
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• 2021

In urban cities, buildings were built in the neighborhood, these buildings influence each other through structure-soilstructure interaction (SSSI) and seismic pounding due to limited separation distance in-between. Generally, the effects of the interaction between soil and structure are disregarded during seismic design and analysis of superstructure. However, the system of soil-base adversely changes structural behavior and response demands. Thus, the vibration characteristics plus the seismic response of a building are not able to be independent of those in adjacent buildings. The interaction between structure, soil, and structure investigates the action of the attendance of adjacent buildings to the others by the interaction effect of the sub-soil under dynamic disturbances. The main purpose of this research is to analyze the effects of SSSI and seismic pounding on the behavior of adjacent buildings. The response of a single structure or two adjacent structures with shallow raft base lying on soft soil are studied. Three dimensions finite element models are developed to investigate the effects of pounding; gap distance; conditions of soil; stories number; a mass of adjacent building and ground excitation frequency on the seismic responses and vibration characteristics of the structures. The variation in the story displacement, story shear, and story moment responses demands are studied to evaluate the presence effect of the adjacent buildings. Numerical results acquired using conditions of soil models are compared with the condition of fixed support and adjacent building models to a single building model. The peak responses of story displacement, story moment, and story shear are studied.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.445-459
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• 1997

The purpose of this study was to investigate of the dietary life, nutritional status and health condition in 100 elderly living in nursing homes in Pusan area. The quality of meals served in nursing homes base on nutrient contents and the state of preferared foods was evaluated by the questionaire and the nutritional status and health condition of subjects were estimated by the analysis of serum components. The results of this study are summarized as follows: 1 Almost all subjects were aged over 70 years and poor-educated. Mean height and weight of subjects were lower than Korean average standard but Body Mass Index(BMI) of those were normal and body fat contents of females were especially high. 2. Protein, vitamin A, vitamin C and Ca intake of subjects were lower than Korean RDA. Subjects preferred pan-broiled for meats and fishes, muchim for vegetables fruits as food between meals. 3. There were no smoking and drinking in almost all subjects. All subjects have taken nutritional supplements, mainly mineral supplements. Prevalence of disease in subjects were in the following order : cardiovascular, stomach, neuralgia in males. The frequency of neuralgia in females was highest. 4. Serum levels of HDL-cholesterol, total cholesterol, triglyceride, total protein, albumin, globulin, Ca and Mg were lower than those of normal ranges. Therefore, it Is necessary to improve nutritional status of the elderly in nursing homes with by increasing the various side dishes and to develop the standard menu for those.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.4
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• pp.386-392
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• 2008

This paper presents active vibration control performance of a hybrid mount. The proposed hybrid mount is devised by adopting both piezostack as an active actuator and rubber as a passive element. After experimentally identifying actuating force characteristics of the piezostack and dynamic characteristics of the rubber, the hybrid mount was designed and manufactured. Subsequently, a vibration control system with a specific mass loading is constructed, and its governing equations of motion are derived. In order to actively attenuate vibration transmitted from the base, a feedforward controller is formulated and experimentally realized. Vibration control responses are then evaluated in time and frequency domains.