금속 및 금속염계 항균제가 혼입된 항균 콘크리트 개발

최홍식,허권,이호범,이시우,곽홍신,Choi, Hong-Shik,Heo, Kwon,Lee, Ho-Beom,Lee, Si-Woo,Kwak, Hong-Shin 한국건설순환자원학회 2013 한국건설순환자원학회 논문집 Vol.1 No.2

하수시설 및 복개 구조물 등은 용해 시 산성으로 작용하는 황화수소에 크게 노출되어, 황산화균의 작용에 의해 강산성의 황산이온이 생성된다. 이에 따라 콘크리트의 생화학적 부식에 의한 열화가 촉진되며, 콘크리트 손상을 더욱 가속화하여 내구성이 크게 저하될 수 있다. 본 연구에서는 콘크리트에서 황산화균이 유기 생체적으로 사용하는 황화수소를 제거하기 위해, 금속의 살균성을 이용하여 금속 및 금속염 분말을 콘크리트에 혼입한 후, 황산화 억제 성능을 평가하였다. 이를 위해 중성화한 콘크리트 시편의 황산화균에 대한 항균 성능을 비교 평가하였고, 급속 염소이온 침투시험을 통해 금속 및 금속염계 항균제 첨가량에 따른 콘크리트 염화물 침투깊이 및 확산계수를 측정하였다. 또한 야외에서 폭로시킨 콘크리트 시편의 표면 상태의 생화학적 상태를 관측하여, 항균콘크리트의 성능 및 적용성을 확인하였다. In the sewage structures and wastewater facilities, concrete is exposed to hydrogen sulfide ($H_2S$) which acts as an acid material in a solution, and a strongly acidic sulfate ion ($SO{_4}^{-2}$) is generated by a sulfuric bacteria. Hence, a degradation of concrete with biochemical corrosion would be accelerated. Finally, durability of concrete and concrete structures may be greatly reduced. In this study, in order to remove the hydrogen sulfide which is used by the sulfuric bacteria organic-biologically, the antibiotic metal and metallic salt powders were mixed to concrete, and a suppressing performance of the sulfate ion was assessed. For the sulfuric acid bacteria, a comparative evaluation of antimicrobial performance on neutralized concrete specimens were carried out, also by a rapid chloride penetration test, chloride penetration depths and diffusion coefficients were measured for antibiotic concrete in accordance with the amount of metal and metallic salt-based antibacterial agents. Eventually, by an observation of the biochemical state of the surface of concrete specimens exposed outdoors, the performance and applicability of antibiotic concrete were confirmed.

서양식 성악발성법의 의학적 이해

최홍식,홍현준,염용혁,남도현,Choi, Hong-Shik,Hong, Hyun-Jun,Yum, Yong-Hyuk,Nam, Do-Hyun 대한후두음성언어의학회 2011 대한후두음성언어의학회지 Vol.22 No.2

Western classical singing voices are different from those of pop song singer's singing voices as well as traditional Korean singing such as Pansori. We anlalysed the singing voices from three different categories with using free application programs available at the usual smart phones : sound level meter and Spectral View Analyzer and fiberoptic rhinolaryngoscopic evaluation. The intensity of voice produced by a classical western singer was 11 dB louder than that produced by a pop song singer. Source sound, glottic sound, as well as harmonic sound and singing resonant sound (Singer's formant) are much more prominent. When evaluated under video-rhinolaryngoscopy during singing, the resonance cavity especially oropharyngeal cavity and hypopharyngeal cavity are widely opened during singing of the western classical singer than those of the traditional Korean singer's singing. Difference of singing methods including producing the glottal sound, respiration and resonance are discussed. Possible explanation of development of 'Singer's Formant' is discussed.

연축성 발성장애(Spasmodic Dysphonia)에 대한 보톡스 주입치료

최홍식,Choi, Hong-Shik 대한후두음성언어의학회 2012 대한후두음성언어의학회지 Vol.23 No.2

Spasmodic dysphonia is a chronic, focal, movement-induced, action-specific dystonia of the laryngeal musculature during speech. It can have a profound effect on quality of life, severely limiting people's communication, especially via telephone and in noisy backgrounds. Spasmodic dysphonia (SD) is usually of the adductor type characterized by glottic contractions causing tightness and voice breaks with forced-strangled voice, but it may also be abductor type or, much less commonly, mixed. Treatment options for adductor spasmodic dysphonia (ADSD) include voice therapy, surgical procedures, and botulinum toxin injections (Botox). The use of Botox injected into the laryngeal muscles remains the "gold standard" treatment for reducing the vocal symptoms of ADSD and Botox induces a temporary paresis of the laryngeal muscles and provides short-term relief of symptoms. Repeated injections of the laryngeal muscles, generally every 3-4 months, are required for continuous relief of symptoms. Improvement in vocal function has been reported after use of Botox injections, though a completely normal voice is rarely achieved. In this hospital, 1,030 patients have been enrolled for Botox injection therapy so far (May, 2012). In this review article, I'd like to present my personal experience of management of spasmodic dysphonia mainly by Botox injection.

Silastic을 이용한 내전 갑상성형술-적용 및 술기

최홍식,Choi, Hong-Shik 대한후두음성언어의학회 2007 대한후두음성언어의학회지 Vol.18 No.1

Unilateral vocal fold paralysis resulting in glottal incompetence can cause significant morbidity attributable to impaired speech, swallowing, and ability to protect the airway. The treatment of unilateral vocal cord paralysis has a long history, marked by technical innovations and improvements. These methods typically use endoscopic injection or implants to augment the volume of the affected vocal fold. The first known treatment, reported by Brunnings in 1911, was paraffin injection. The first thyroplasty medializing the paralysed vocal cord was performed by Payr in 1915 ; here, a cartilage door-flap was created from the thyroid ala to obtain better voice quality. In the 1970s, Isshiki systematized and developed the use of the external medialization by Payr. Later he modified his original technique, and achieved safer and better results. Many other methods were introduced for external medialization during the 1980s and 1990s. There has been couple of materials using for medialization laryngoplasty: silicone bloc, cartilage, goretex (polytetrafluoroethylene), titanium, etc. Among them, silicone bloc is the most popularly used material. Type I thyroplasty in combination with arytenoid adduction is a proven technique for medialization of the paralysed vocal fold. In this paper, personal experience for using silicone bloc type I thyroplasty : decision making and practical points, long-term results and complication of the procedure will be discussed.

585-nm Pulsed Dye LASER를 이용한 성대 폴립의 치료

최홍식,이근완,김민호,권순호,전주현,김광문,Choi, Hong-Shik,Lee, Kun-Wayn,Kim, Min-Ho,Kwon, Soon-Ho,Jeon, Ju-Hyun,Kim, Kwang-Moon 대한후두음성언어의학회 2007 대한후두음성언어의학회지 Vol.18 No.1

Background and Objectives: The 585-nm pulsed dye laser (PDL) has recently been adopted by otolaryngologists because of its epithelial-sparing properties. Many authors have reported the use of PDL for treatment of various vocal cord lesions. This purpose of this study is to examine the effectiveness of 585-nm PDL in the treatment of vocal polyp. Materials and Methods: Eight patients with vocal polyp were treated with 585-nm PDL from Sep. 2006 to Nov. 2006 in Yong-dong Sevrance hospital. 5 of them went through local anesthesia and 3 of them went through general anesthesia. In order to control laser fiber, flexible digital transnasal laryngoscope was applied under local anesthesia and general anesthesia using LMA, and micromanipulator was used under general anesthesia using endotracheal tube. The evaluations of vocal function was done at pre-and postoperation. Results: All patients improved in the perceptual evaluation of voice after PDL surgery. The aerodynamic study revealed that 5 of 8 patients showed improvement in maximal phonation time, and 6 of 8 showed improvement in mean airflow rate during phonation. The acoustic analysis revealed that all patients showed improvement in Jitter and Shimmer, and 7 of 8 showed improvement in noise to harmony ratio. Conclusion: This study demonstrates promising results in the efficacy of 585-nm PDL for the treatment of vocal polyps, and it illustrates a new option for vocal polyp treatment as well as the advantage of PDL surgery.

조습재료와 물-시멘트비에 따른 콘크리트의 강도 및 염분 침투 평가

최홍식 ( Choi Hong-shik ),허권 ( Heo Gweon ),이시우 ( Lee Si-woo ),홍기남 ( Hong Gi-nam ),박정천 ( Park Jeong-cheon ) 한국구조물진단유지관리공학회 2008 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.12 No.2

Recently, people take a great interest in comfortable environment for health. However, the humidity of indoors can not be controled with the incresing complexites of life. So that the humidity controllable concrete is required. But it is expected that the strength and the durability of the concrete mixed with the humidity control materials may be changed. In this studies, the durality and the strength of the concrete mixed with humidity control materials is evaluated by the experiments of RCPT. Pearlite and rice straw is used as the humidity control materials. The results of this work is that the strength and the durability of the concrete is decreased with increasing humidity control materials and W/C ratio.

광범위한 국소재발 및 경부, 종격동 전이를 동반한 유두상 갑상선암 1례

최홍식(Hong Shik Choi),이주형(Ju Hyoung Lee),김재원(Jae Won Kim),양해동(Hae Dong Yang) 대한두경부종양학회 1997 대한두경부 종양학회지 Vol.13 No.1

The papillary carcinoma is the most common malignant neoplasm of thyroid gland and the prognosis is better than anyother type of thyroid carcinoma. However, the thyroid is closed to the important organs such as esophagus, trachea and larynx, there are some possibilities to invade these organs. In case of advanced disease, not only surrounding structures but also mediastinum and cervical lymphatic chain can be involved or distant metastasis develops frequently. Therefore in these cases the prognosis is worse and the rate of inoperable case is more than those of non-metastatic group. Generally, the treatment modality for papillary thyroid carcinoma consists of surgery, postoperative thyroid hormone and radioiodine therapy. If the tumor invades surrounding structures, cervical lymph node or mediastinum, total thyroidectomy and wide excision of tumor invaded area including mediastinal dissection and neck dissection is necessary. Recently, the authors have experienced a case of locally invasive and recurred papillary thyroid carcinoma without treatment for 7 years. The patient was performed previously thyroid lobectomy and isthmusectomy 13 years ago. We had determinded surgical therapy for this patient and performed mass excision with overlying skin, completion total thyroidectomy, right type I modified radical neck dissection, left lateral neck dissection, thoracotomy with supramediastinal dissection, shaving of diffusely involved trachea and skin defect reconstruction with pectoralis major myocutaneous flap. After operation 2 cycles of radioiodine therapy were taken. Now the patient is following up at the outpatient base and no evidence of disease state for postoperative 16 months. So we report on this case with a brief review of literature.

조습콘크리트의 실용화를 위한 적용성 연구

최홍식 ( Choi Hong-shik ),허권 ( Heo Gweon ),이시우 ( Lee Si-woo ),이성로 ( Lee Seong-lo ),박정천 ( Park Jeong-cheon ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.2

The wellbeing circumstance is the first objective of the recent human society. This paper discussed about the moisture absorption ability of the concrete material as like pearlite, vermiculite, pulp and rice straw. The most absorptive rice straw. In this paper, pearlite is used as an aggregate and the rice straw is used as a filler with small amounts.

원로와의 대화_우리학회 명예회원 구봉근 교수님과 함께...

최홍식(Hong-Shik Choi),홍기남(Ki-Nam Hong) 한국콘크리트학회 2009 콘크리트학회지 Vol.21 No.2

콘크리트 표면의 생태계 물질에 의한 오염연구

최홍식 ( Choi Hong-shik ),허권 ( Heo Gweon ),이시우 ( Lee Shi Woo ),이명규 ( Lee Myong-gyu ),안지은 ( An Ji-eun ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.2

This study discussed about the pollution due to the ecosystem on the concrete surface. The concrete surface was decaied in the order of the higher humidity and the shading green algae. The black ecosystem substance as like Clisterium sp. etc. grow well at the a higher humid and shading place. The increment of ecosystem substance independed on the neutrality of concrete, that would be depended the environment of the concrete.