• 공업화학
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• 제5권6호
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• pp.1056-1061
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• 1994

$80^{\circ}C$에서 열처리하거나, $80^{\circ}C$와 상대습도 85%인 습도 조건에서 처리한 황동이 피복된 강선 코드의 표면 상태와 고무와 접착 성질을 조사하였다. 열처리로 황동의 산화가 진행되었으며, 습윤처리 후에는 더 심하게 산화되었다. 처리기간이 길어질수록 전처리한 코드의 접착 성질이 나빠졌으며, 고무부착 정도가 심하게 저하되었다. 황동 피복층의 산화로 인한 코드의 접착 성질 저하를 산화아연층의 과도한 성장과 연계지어 설명하였다.

• Tuberculosis and Respiratory Diseases
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• 제52권3호
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• pp.265-270
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• 2002

운동유발성 호흡곤란으로 내원하여 운동유발성 천식으로 치료 하였으나 증상 호전이 없어 운동후 기관지 내시경을 시행하여 성대기능이상을 확진하고 치료한 운동유발성 성대기능이상 1례를 문헌고찰과 함께 보고하는 바이다.

• 화약ㆍ발파
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• 제27권1호
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• pp.1-6
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• 2009

취수정 내의 스트레이너는 수중의 이물질, 토사 등에 의해 폐쇄되어 투수율이 떨어지게 된다. 본 연구에서는 도폭선의 폭발압력을 이용하여 스트레이너를 재생하는 방법을 제시하고 적용 가능성을 검토하였다. 물이 채워진 수조 내에서 도폭선 발파를 시행하여 스트레이너에 손상을 주지 않는 범위의 압력을 산정하였다. 실험결과 $3,000\;kg/cm^2$ 정도의 충격압이 직경 12 cm인 스트레이너를 손상하지 않고 재생하기에 적절한 것으로 판단되었다. 스트레이너에 부착시킨 모르타르는 거의 완전하게 탈락되었다.

• 대한후두음성언어의학회지
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• 제7권1호
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• pp.27-31
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• 1996

The voice of aged persons is known generally to be somewhat different from that of other adults, suggesting that laryngeal change occurs with advancing age. However, because knowledge of the voice characteristics of aged persons is limited, it is difficult to judge whether their voices arc normal. Chart review and laryngoscopic examination from ninety-one patients with hoarseness over the age of 60(1st group) and one hundred sixteen patients with hoarseness below the age of 50(2nd group) were done to define aging related voice disorders. The following results were obtained. 1) Associated diseases related to laryngeal disease were hypertension(12%), pulmonary disease(4.4%), thyroid disease(1.1%) in 1st group and hypertension(9.5%), thyroid disease(1.7%) in 2nd group. 2) The underlying diseases causing hoarseness in order of frequency were benign vocal fold lesion(37.7%), inflammatory disease(36.8%), functional dysphonia(17%) in 1st group and benign vocal fold lesion(43.6%), functional dysphonia(26.3%), inflammatory disease(16.5%) in 2nd group. 3) In stroboscopic findings, atrophy and sulcus of vocal cords are more prevalent in males than in females and edema of vocal cords is more common in females. Generally the voice characteristics of aged persons depend on the mass of the vocal folds which may be decreased through atrophy or be increased by edema. However, other factors such as systemic diseases, drug side effects and compensatory mechanism to presbylaryngis must be taken into account in diagnosing and treating voice disorders in aged persons.

• 대한후두음성언어의학회지
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• 제28권1호
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• pp.25-31
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• 2017

Background and Objectives : Though voice therapy is proven to be effective in academia, treatment results and satisfaction level are inconsistent in clinics. The inconsistency may rise from diverse vocal cords misuse patterns in patient population as they suffer from different diseases or have bad phonation habits. In order to overcome the limitation, we uniformized patients' vocal cords with injection laryngoplasty prior to voice therapy. The efficacy of voice therapy and consistency in treatment results after injection laryngoplasty were assessed. Materials and Methods : Patients diagnosed with vocal nodules were either treated with injection laryngoplasty followed by voice therapy (combined treatment group) or voice therapy only (voice therapy group). Each group consisted of 15 patients. Acoustic measures (jitter, shimmer, NHR), aerodynamic measures (MPT, Psub, MAFR), and subjective auditory conscious measures (K-VHI, K-VRQOL) between two groups were analyzed. Results : After treatments, both groups improved in terms of acoustic, aerodynamic, and subjective auditory conscious measures compared to pre-treatment. Combined treatment group had statistically significantly greater improvement in shimmer, P in K-VHI, and PF in K-VRQOL compared to voice therapy group. Conclusion : Injection laryngoplasty treatment prior to voice therapy synergizes in treating patients compared to voice therapy only.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.238-241
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• 2007

A roller straightening process is a metal forming technique to improve the geometric quality of products such as straightness and flatness. The geometrical quality can be enhanced by eliminating unnecessary deformations produced during upstream manufacturing processes and minimizing any detrimental internal stress during the roller straightening process. The quality of steel cords can be achieved by the roller straightening depends the process parameters. Such process parameters are the roll intermesh, the roll pitch, the diameter of rolls, the number of rolls and the applied tension. This paper is concerned with the design optimization of the roller straightening process for steel cords with the aid of elasto-plastic finite element analysis. Effects of the process parameters on the straightness of the steel cord are investigated by the finite element analysis. Based on the analysis results, the optimization of the roller straightening process is performed by the response surface method. The roller straightening process using optimum design parameters is carried out in order to confirm the quality of the final products.

• 대한의용생체공학회:의공학회지
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• 제17권3호
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• pp.297-304
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• 1996

Although collagen is still considered to be a poor immunogen, animals can produce antibodies to a number of different sites in the collagen molecule. In type I collagen, three classes of antigenic determinants have been described those are recogrlized as different degrees in different species. These are essentially composed of helical, conformation-dependent antigenic determinants and terminal, nonhelical antigenic determinants, and finally central antigenic determinants exposed only after denaturation of the collagen molecule. To utilize collagen as implantable biomateriall human e61bryonic collagen, ten immunological to body, was purified from human umbilical cords and found to contain [$\alpha$1(I)]$_2$. [$\alpha$2(I). Each step of purification were observed by polarized light microscope and analyzed through SDS-PAGE. The conclusious are follows; 1 . The purified collagen revealed gradual fiber indenties on each step of purification by polarized microscope. 2. The structual changes of extracted collagen as removed telopeptide were confirmed by SDS-PAGE.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.475-476
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• 2007

Electroglottography (EGG) is a technique used to register laryngeal behavior indirectly by a measuring the change in electrical impedance across the throat during speaking. However, EGG waveform is affected by laryngeal muscles which fluctuate the vocal cords, and which result in baseline wander. It is required to reduce baseline wander in EGG waveform, because EGG waveform is used for input signal of nonlinear speech synthesizer in next chapter. In vocal cords, the abduction-adduction of glottis is mainly controlled by the posterior cricoarytenoid (abductor) and interarytenoid (adductor) muscles respectively. Empirical Mode Decomposition method was adopted in cancellation of EGG waveform baseline wandering, and showd better performance than that of high pass filter with 500 order.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.330-334
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• 2004

In this paper, we studied on the fire dispersive patterns and the fire progress at the power cord sets for low voltage appliances in the wall-model. For the experiment, we manufactured a wall-model and applied the external flame at the power cord sets. From the results, short-circuit of the power cord sets was haunted by the external flame it was disconnected with the flashing and the scattering. The fire progress on the polyvinyl chloride insulated flexibel cords is not observed because the ignition energy decreases. In case of rubber insulated flexible cords, however, the fire was progressed continuously. Molten marks were formed at a two electric wire by continuous electric discharge in power source part. A large molten mark was formed in load part. And the columnar structure and voids were observed in molten wire.

• 한국안전학회지
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• 제19권1호
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• pp.60-65
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• 2004

The PVC insulated flexible cords are used mainly as power supply cords of electric appliance. This electric wire is a stranded wire consisted of dozens of strands. In case stranded wires are disconnected by mechanical stress, it weakens electrically. Finally, the over current flows through stranded wires, and electrical fire occurs. In this study, we analyzed the melting properties of strands by over current, such as melting process, melting current and melting time. And we analyzed that quantity of heat for melting, a cross sectional structure, and surface structure by optical microscope and SEM. As analysis results, melting time decreased as melting current increased. And quantity of heat for melting was low, too. From the cross sectional structure of melted wire, when a melting current low and melting time long, it was found that the dendrite structure grew. However, the dendrite structure is hard to grow because growing time is not enough when a melting current high and melting time short.