• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.43 no.3 s.309
• /
• pp.76-83
• /
• 2006

A main objective of audio equalizer is for user to tailor acoustic frequency response to increase sound comfort and example applications of audio equalizer includes large-scale audio system to portable audio such as mobile MP3 player. Up to now, all the audio equalizer requires manual setting to equalize frequency bands to create suitable sound quality for each genre of music. In this paper, we propose an intelligent audio graphic equalizer system that automatically classifies the music genre using music content analysis and then the music sound is boosted with the given frequency gains according to the classified musical genre when playback. In order to reproduce comfort sound, the musical genre is determined based on two-step hierarchical algorithm - coarse-level and fine-level classification. It can prevent annoying sound reproduction due to the sudden change of the equalizer gains at the beginning of the music playback. Each stage of the music classification experiments shows at least 80% of success with complete genre classification and equalizer operation within 2 sec. Simple S/W graphical user interface of 3-band automatic equalizer is implemented using visual C on personal computer.

• The Journal of Korean Academy of Prosthodontics
• /
• v.44 no.5
• /
• pp.594-605
• /
• 2006

Statement of problem: Modification of titanium implant surface has potential to ensure clinically favorable performance that several surface modification technologies have been introduced. Among the methods. anodizing method and sol-gel hydroxyapatite coating method have gained much interest due to its roughness and chemical composition of the coating layer, but more of its biocompatibility result is required. Purpose : The purpose of this study was to compare bone-implant interface shear strength of four different surface treated implants as time elapsed. Resonance frequency analysis(RFA) and removal torque measurement methods were employed to measure implant stability at one week and six week after implantation. Material and method: A total of 80 screw-shaped implant [20 machined, 20 resorbable media blasted(RBM), 20 anodized, and 20 anodized+hydroxyapatite sol-gel coated] were prepared, and one of each group was implanted in the tibia of a New Zealand white rabbit that total 20 of them were used. In order to test the implant stability and implant-tissue interface contact changing in the bone bed, each 10 rabbit were sacrificed 1 week and 6 week later while resonance frequency and removal torque were measured. One-way analysis of variance and the Tukey test were used for statistical analysis. Results : The results were as follows. 1. There was no statistically significant difference of implant stability quotients(ISQ) value in RFA between individual groups after 1 week of implantation and 6 weeks(p>0.05). But, there was statistically significant increase of ISQ value in 6 weeks group compared to 1 week group(p<0.05). 2. There was no statistically significant difference in removal torque analysis between individual groups after 1 week of implantation and 6 weeks(p>0.05). but there was statistically significant increase in all 4 groups after 6 weeks compared to 1 week later(p<0.05). 3. There was no statistically significant difference in removal torque analysis between anodized group and HA coating after anodic oxidation 6 weeks later(p>0.05), but significant difference was appeared in both groups compared to RBM group and smooth-machined group(p<0.05). Conclusions : It can be suggested that changes in surface characteristics affect bone reactions. Anodized and anodized+hydroxyapatite sol-gel coating showed significantly improved bone tissue response to implants, but further study on the effect of hydroxyapatite dissolution is needed.

• Journal of Korean Medical Ki-Gong Academy
• /
• v.10 no.1
• /
• pp.130-157
• /
• 2007

The purpose of this research is to seek for efficient health maintenance device and to suggest desirable daily habit, based on the inquiry on interrelationship between workers' daily lives and their heartbeat change level. The paper survey about general features, case history and daily habits was conducted on workers during medical examination in Jeollabukdo, and examined their change of heartbeat as well. The results of research deducted from data analysis are as follows; 1. There found very positive interrelations between time-domain analysis and frequency-domain analysis, and MHR and LF/HF ratio had negative connection with other analyses. 2. The recipient showed high time-domain analysis when they are younger, have worked shorter or have spouse, and it contributes to stable sympathetic nerve and parasympathetic nerve as it stimulates autonomic nervous system. 3. According to the result of frequency-domain analysis, recipients showed higher TP and LF when they are younger, and the highest HF when they are under 34.The level of VLF was higher for university graduates than the ones who finished high school. The recipients showed higher TP and HF when they don't have spouse, and lower TP, LF and HF when they have worked longer. 4. The level of RMSSD and TSRD was high for the people who don't have case history, and HF was high when they don't have any disease in progress. 5. According to the result concerning correlation of daily habits with time-domain analysis and frequency-domain analysis, cigarette, alcohol and sleeping hours don't affect heartbeat change, but the ones who regularly workout showed higher result in every analysis. It shows that the autonomic nervous system of recipients who regularly exercise response more actively. The result mentioned above suggests that the change of heartbeat is a direct index which shows the change of autonomic nervous system, and it depends on the exercise the most. Thus, workout is proved to be the best method in order for workers to take care of their health.

• Journal of Advanced Marine Engineering and Technology
• /
• v.38 no.6
• /
• pp.632-638
• /
• 2014

Nowadays, as part of an effort to increase the efficiency of propulsion shafting system, the revolution of the main diesel engine in CMCR(Contract Maximum Continuous Rating) is reduced whereas the stiffness of hull structure supporting the main diesel engine is relatively flexible. However, vibration problems related with resonant response of main diesel engine are increasing although top bracing is installed between the main diesel engine and the hull structures to increase natural frequency of engine body above CMCR to avoid resonant phenomenon. In this study, the dynamic characteristic of top bracing is reviewed by analyzing measuring results of general cargo ships which apply the hydraulic type instead of the friction type to control the natural frequency and the vibration of the engine body. Moreover, considering the vibration characteristic of the engine body and the hydraulic type of the top bracing by varying the number of top bracing, authors suggest the more effective way to control the vibration of the engine body despite of lower stiffness of the hull structure than in the past when the hydraulic type of top bracing is used.

• Journal of Plant Biotechnology
• /
• v.33 no.4
• /
• pp.271-276
• /
• 2006

Hypocotyl explants of Chinese cabbage (us. 'Jeong Sang' and 'Seoul') produced adventitious shoots on Murashige and Skoog (MS) basal medium supplemented with 4mg/L $AgNO_3$, 5 mg/L acetosyringone, 4 mg/L 6-benzyladenine and 3mg/L alpha-naphthaleneacetic acid (SI) after cocoultivation with strains of Agrobacterium tumefaciens (LBA4404) harboring the pCAMBIA1301 and the $_PPTN290$ containing hygromycin-resistance gene and paromomycin-resistance gene as a selectable marker genes, respectively. There was a significant difference in the frequency of transgenic plants depending on antibiotics and cultivars used. Paromomycin was better than hygromycin, and cultivar 'Jeong-sang' was higher than 'c.v. Seoul' in the frequency of transgenic plants. In particular, the highest frequency (0.70%) of transgenic plants was obtained from selection medium (SI) containing 100mg/L paromomycin in c.v., 'Jeong-sang' GUS positive response were obtained 9 plants and 3 plants from the cultivars, 'Jeong-sang' and 'Seoul', respectively. They were grown to maturity in a greenhouse and normally produced $T_1$ seeds. GUS histochemical assay for progeny $(T_1)$ revealed that the transgenes were expressed in the plant genome.

• Korean Journal of Community Nutrition
• /
• v.12 no.3
• /
• pp.259-271
• /
• 2007

The purpose of this study was to investigate the dietary habits and daily intake of nutrients in college students. This survey was conducted using a self-administered questionaire. The average heights and weights were 173.5 cm and 72.3 kg of male students and 161.8 cm and 57.2 kg of female students. The average of BMI was $24.2kg/m^2$ of male and $21.9kg/m^2$ of female, and the value of male students was higher than the value of female students. The response to the daily meals was 54.6% for '$2{\sim}3$ times/week'. The regularity of mealtime was 41.7% for irregular and the frequency eating after nine was 45.7% for '5-6 times/week', respectively. The repast was 72.2% for 'overeating and little eating' and was a significant difference of male and female students (p<0.05). The eating rate was higher '$10{\sim}20min$'. As for breakfast food eaten, skipping breakfast was 23.6% for 'no/week' and female students were higher than male students (p<0.05). The frequency of snacks was 36.0% for 'nothing' of males students and 34.8% for '3-4 times/week' of female students (p<0.05). The type of snack was a significant difference of males and females students (p<0.01), and was the highest 75.0% for carbonated drinks of males and 37.5% for snacks of females. The eating due to stress solution was a significant difference of male and female students (p<0.01), and was the highest 23.0% for 'frequency' of males and 44.7% for 'sometime' of females. As for food intake of male and female students, the meat intake was 66.7% for 'everything of male and female students. The fish intake was 68.1 % for '1-2times/week'. The milk, milk products, eggs and beans were each 40.3%, 58.3%, 56.9%, 47.2% for '1-2 times/week' (p<0.05). The fat intake was 55.6% for '$1{\sim}2$ times/week'. The average consumption of energy was 58% of male and 67% of female of estimated energy requirement (EER). Their mean ratio of carbohydrate: protein: fat was 57 : 15 : 28 of all subjects. The mean intakes of vitamin C and folic acid were 70% and 51% of males and 62% and 52% of females of recommended intake (RI). The mean intakes of Ca, P, Fe and Na were 71%, 140%, 146% of males and 72%, 122%, 76% of female of RI and 273% of males and 233% of females of adequate intake (AI). Therefore, nutritional education is necessary for college students to establish physicall and mentall optimal health conditions though nutritional intervention.

• Journal of Food Hygiene and Safety
• /
• v.18 no.3
• /
• pp.101-106
• /
• 2003

The aim of this study is to develop a label-free immunosensor for microbial detection and to evaluate its applicability to Pseudomonas aeruginosa detection in various food samples. The antibodies used were a polyclonal antiserum from rabbit (polyvalent type) and a monoclonal antibody raised against the flagella of P. aeruginosa. Antibody immobilization was done by a thiolated antibody chemisorption onto one gold electrode of a piezoelectric quartz crystal with a thiol-cleavable, heterobifunctional cross-linker, sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate. To the Stomacher-treated samples from various raw and processed foods under cold storage, comprising sirloin, cod and pettitoes, spiking and enrichment culture were done to prepare the model samples, followed by the measurements of the frequency shifts after sample injections. The frequency shifts obtained by the sample matrices themselves were in the range of 52~89 Hz. The injections of the spiked samples caused the frequency shifts of 108~200 Hz, whereas the enriched samples decreased the steady-state resonant frequencies by 162~222 Hz. All sample measurements including baseline stabilization, sample injection and acquisition of the steady-state response were accomplished within 30 min.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.4
• /
• pp.555-563
• /
• 1999

Background: Chronic cough is a common symptom that requires the systematic diagnostic approach for proper evaluation. Postnasal drip syndrome(PNDS), bronchial asthma, gastroesophageal reflux disease(GERD), and chronic bronchitis are among the common causes. This study was conducted to evaluate the spectrum and the frequency of the causes of chronic cough. Methods: We prospectively evaluated 93 patients who had chronic cough despite normal chest radiographic finding. History and physical examination were done along with paranasal sinus radiograph, spirometry, bronchoprovocation test and 24-hours' ambulatory aesophageal pH monitoring as necessary. Results: Forty-nine(52%) of the 93 patients had PNDS, 15 patients(16%) bronchitis, 10 patients(11%) asthma, 4 patients (4%) GERD, 7 patients (8%) both PNDS and asthma, 4 patients (4%) undiagnosed condition and 4 patients(4%) were taking ACE inhibitor. Sixty-nine percent of the patients with PNDS improved after follow up, 73% patients with bronchitis, 80% patients with asthma, 50% patients with GERD, 100% patients with both PNDS and asthma, and 100% patients with ACE inhibitor. Conclusion: PNDS was the most common causes of chronic cough. Bronchitis was the second and asthma the third in frequency. The etiology of chronic cough can be determined easily by history and physical examination, successful therapy initiated in most patients. The response to specific therapy also was important in evaluation of chronic cough.

• Journal of the Korean Society for Railway
• /
• v.20 no.2
• /
• pp.165-172
• /
• 2017

High frequency squeal noise can be generated when a railroad vehicle runs a sharp curved section; this noise causes environmental complaints and excessive wear on the wheel and the railroad track. In this paper, curved squeal noise experiments on a commercial railway were carried out to investigate this phenomenon. The relationship of the squeal noise pressure level, the frequency characteristics, the railway running speed, and the modal behavior of the wheel were investigated. At the same time, the lateral motion of the wheel relative to the rail was captured using a video camera; wheel movement was calculated when the noise was generated. queal noise occurred at the highest level at the inner front wheel; this phenomena is considered to be related to the lateral vibration response characteristics of the wheel. It can be seen that the magnitude of this squeal noise is not directly related to the increase in vehicle speed.

• Geophysics and Geophysical Exploration
• /
• v.20 no.2
• /
• pp.88-95
• /
• 2017

Chogye basin, which is surrounded by country rock, has a closed-basin form. In such a basin, incident seismic energy can form multiply reflected waves, thus causing energy concentration to occur at this closed-basin area. Microtremor measurement survey was performed at the Chogye basin, which is located in Chogye-myeon and Jeokjungmyeon, Hapcheon-gun, Gyeongsangnam-do, Republic of Korea. Microtremor data were transformed into the frequency domain, and then the horizontal-to-vertical spectral ratios (HVSR) were calculated. Fundamental resonance frequencies were estimated from the HVSR results for every observation point. Using the empirical relationship between site period and thickness for sediment sites in Korea known from the previous study, the distribution of sediment thickness of the Chogye basin was estimated from the fundamental resonance frequencies. Being compared with the mountainous rim with steep slope, the measurement points inside the basin have low values of the fundamental resonance frequency with the minimum of 1.03 Hz, which corresponds to the thickness of sedimentary layer with the maximum depth of about 100 m. A three-dimensional basin model was constructed for bedrock topography of the Chogye basin by an interpolation of basin depths estimated at each measurement site.