나노필라멘트 직물의 광학적 특성에 관한 연구

최세진,예나경,민문홍,김한성,Choi, Se Jin,Ye, Na Kyung,Min, Mun Hong,Kim, Han Seong 한국섬유공학회 2013 한국섬유공학회지 Vol.50 No.2

The most important characteristic of a nanofilament fabric is that it has a significantly higher surface area than conventional fabrics. Such nanofilament fabrics exhibit new physical properties that are unknown in conventional fibers, and it is anticipated that future demand of nanofilament fibers with improved fiber functionality could significantly increase. In this study, in order to analyze the size effect of the fiber, the optical properties of 800 nm and 600 nm filament fabrics were compared. The results showed that the 600 nm fabric had significantly more luster and less transparency as compared to the 800 nm fiber.

리스페리돈이 심혈관계에 미치는 영향

최세진,전진숙,최영태,Choi, Se-Jin,Cheon, Jin-Sook,Choi, Young-Tai 대한생물정신의학회 2000 생물정신의학 Vol.7 No.2

Objectives : Risperidone is a new antipsychotic drug developed to overcome the therapeutic limitation of conventional antipsychotics. It responses to negative as well as positive symptoms by blocking both dopaminergic and serotonergic receptors, causing no significant side effects such as agranulocytosis and seizure. It is, however, not known whether it induces any serious cardiovascular side effects as evoked by other conventional antipsychotic drugs. The aims of this study were to evaluate the effect of risperidone on cardiovascular function, and to discuss the factors affecting the cardiovascular function. Methods : For 42 patients(22 males and 20 females) diagnosed as schizophrenia, schizophreniform disorder or schizoaffective disorder according to the DSM-IV classification, the cardiovascular fuctions such as heart rate, systolic and diastolic blood pressure, PR interval, QRS interval and QT interval were successively checked before and after 2 weeks and 4 weeks risperidone administration. Furthermore, variables such as body weight, Brief Psychiatric Rating Scale(BPRS), Clinical Global Impression(CGI), Extrapyramidal Symptom Rating Scale(ESRS), Anticholinergic Rating Scale(ARS), serum cholesterol level, serum triglyceride level, serum high-density-lipoprotein level, serum WBC, serum Hb, serum platelet level, prothrombin time and partial thromboplastin time were also analyzed before and after 2 weeks and 4 weeks risperidone administration. Results : 1) Risperidone treatment resulted in a significantly decreased heart rate and increased QT interval after 4 weeks administration(p<0.005 respectively). 2) The scores of BPRS and CGI were significantly decreased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). The scores of ESRS and ASRS were significantly increased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). 3) There were positive correlations between heart rate after 4 weeks and total dose(P<0.05). Blood pressure was significantly(p<0.05) correlated with sex(higher in male) and significantly(p<0.05) positive correlated with body weight. QT interval was significantly(p<0.05) correlated with sex(longer in female) and smoking history(shorter in smokers). Conclusions : Risperidone could induce significant change in heart rate and Q-T interval. Therefore, the cardiovascular safety for risperidone should be reconsidered according to the duration and dosage increase.

전도성 방적사 및 필라멘트사를 이용한 섬유형 전극 정전용량형 터치 센서의 성능 비교 연구

최세진,방주엽,민문홍,이창헌,김한성,Choi, Sejin,Bang, Ju Yup,Min, Moon Hong,Lee, Chang Heon,Kim, Han Seong 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.6

With the rapid growth of the Internet of things in the recent years, smart textile technologies have correspondingly attracted significant research attention in the industry. One important elementary technology being considered for smart textiles is a touch sensor input device to enable direct communication between users and other electronic devices. This study investigated the effect of the structural difference in conducting fibers on the sensing property of capacitive textile touch sensors. Conducting fibers made of stainless steel spun yarns and filaments used for electrodes presented different changes in electrical resistance with the application of tensile and compressive forces. It is believed that the different structures between spun yarns and filaments induced difference in the electric contact among their constituent fibers with the application of an external force. Moreover, the random deformation of staple fibers resulted in the unstable change of capacitance and large hysteresis, while a stable performance and low hysteresis was observed for textile sensors with filaments.

혼화재 종류 및 치환율에 따른 모르터의 조기강도 특성에 관한 연구

최세진,이성연,김성수,Choi, Se-Jin,Lee, Seong-Yeun,Kim, Sung-Su 한국건축시공학회 2007 한국건축시공학회지 Vol.7 No.2

Recently, due to the increase of high-rise buildings construction, many researches for making harden of concrete earlier and remove of forms faster are being performed to reduce construction period. In this study, we compared and analysed the early strength properties of mortar according to the kinds and replacement ratio of mineral admixture to select the kinds and replacement ratio of mineral admixture of high early strength concrete. For this purpose, mortar mixtures according to the kinds(FA, MK, ZR, BFS, DM) and replacement ratio(0, 2, 4% by volume of sand) of mineral admixture were selected. From our test data, early-age compressive strength decreased in accordance with the increase of replacement ratio of fly-ash(FA) & blast furnace slag powder(BSF) and, in case of addition admixture, early-age compressive strength of with containing 4% appeared higher compared with containing 2%.

폴리올레핀계 단성분 부직포 및 이성분 시스-코어 복합부직포의 열융착 거동에 관한 연구

최세진,이도준,이현석,김한성,Choi, Se Jin,Lee, Do Jun,Lee, Hyun Seok,Kim, Han Seong 한국섬유공학회 2017 한국섬유공학회지 Vol.54 No.2

In this study, we have investigated the difference between the thermal bonding behaviors of mono-component and sheath-core nonwoven fabrics used as hot-melt adhesives. The difference between the manufacturing processes and the melting points of the nonwoven fabrics lead to a difference in their thermal bonding behavior. This was confirmed through image analysis by observing the change in the thermal shrinkage and the pore size ratio with temperature. The difference in the behavior of the fibers is also explained by dynamic mechanical analysis. The analysis of the thermal bonding mechanism of the hot-melt nonwoven fabrics can be used as a supporting data for their manufacturing process in order to improve the performance of the hot-melt adhesives and the design adhesion strength.

LMPET/PET 시스-코어 부직포의 온도에 따른 접착특성 및 물성 변화에 관한 연구

최세진,임지환,김한성,Choi, Sejin,Lim, Ji Hwan,Kim, Han Seong 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.2

In this study, a sheath-core, non-woven material composed of a low-melting-point polyester (LMPET) and regular PET was used as an adhesive layer and a regular PET textile was used as a surface layer for the unification of materials. Herein, we investigated the complex adhesion properties, caused by the structural deformation at different bonding temperatures, of a two-component non-woven material. It was confirmed that the structural deformation of the non-woven material was significantly changed near the bonding temperature of $180^{\circ}C$ due to the change in fluidity of the low-melting point component. The effects of the structural change on the properties, such as the induced shrinking and wrinkling as well as changes in the bonding strength and air permeability, of the sheath-core, non-woven material are discussed. In addition, it is expected that these results, including the compression characteristics, flexibility, and durability, may provide the possibility for the manufacturing of products that include this material.

이미지 프로세싱을 이용한 상용 의류관리기의 먼지 입자 제거 성능 분석법 및 상용 의류관리기의 성능 평가에 관한 연구

최세진,황영진,이효정,김미경,김선곤,김한성,Choi, Sejin,Hwang, Young Jin,Lee, Hyo-jung,Kim, Mi Kyung,Kim, Sun Gon,Kim, Han Seong 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.2

We have investigated, by a quantitative evaluation method, the efficiency of the removal of particulate matter that was attached to clothing, by using a clothing care system. We utilized a proper, standard image-processing method as well as experimental conditions which simulated an outdoor environment in order to ensure reliability. The kinetic energy loss, which occurred during the energy transfer, which was required to detach the dust particles from clothing was also studied with visual evidence in the form of high-speed images. The development of this method for the evaluation of particle removal which is based on direct, visual measurements, instead of indirect analogous interpretations, is expected to be useful for various fields that require precise quantitative evaluation.

PP 및 PE/PP 시스-코어 부직포의 열융착 거동의 차이에 기인한 접착 특성 및 통기성에 관한 연구

최세진,이도준,박충렬,이현석,김한성,Choi, Sejin,Lee, Do Jun,Park, Choong Ryoel,Lee, Hyun Seok,Kim, Han Seong 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.6

Herein, the thermal adhesion behavior of polypropylene (PP) mono-component and polyethylene/PP sheath-core non-wovens was investigated. The materials generally showed good mechanical properties and environmental benefits. The proper bonding temperature was determined because thermal bonding among fiber networks results in adversely affects bonding strength and structural integrity. The morphology of the adhesive interface, thermal shrinkage, wrinkle properties, and compressive properties were also characterized and showed that differences in thermal behaviors due to the material and dimensional variation affected bonding strength and air permeability. It is expected that these results, that also include flexibility and durability measurements, will provide guidance for the manufacturing of products containing these materials.

초고속 카메라 노출시간을 이용한 전기방사 속도 계측에 관한 연구

최세진,하용구,김한성,Choi, Se Jin,Ha, Yong Koo,Kim, Han Seong 한국섬유공학회 2014 한국섬유공학회지 Vol.51 No.6

Electrospinning is a technology for producing nanofibers using high voltages. In this study, we investigated jet velocities and the corresponding electrospinning mechanisms using high-speed camera observation. Moving jets were observed at various exposure times for obtaining reliable velocity data. Significant differences were observed in the velocities according to the position between the tip and collector, as a function of applied voltages. However, the jet was found to consistently progress at 3-5 m/s near the collector. This suggests that the drawing effect of the electrospun fiber, induced by bending instability, occurs in a limited region.

성대마비와 성대구증의 강도 변화에 따른 최대발성지속시간 비교

최세진(Choi Sejin),최홍식(Choi Hong-Shik),김재옥(Kim Jaeock),최예린(Choi Yaelin) 한국음성학회 2012 말소리와 음성과학 Vol.4 No.1

The patients with incomplete glottic closure have an important feature decreasing the maximum phonation time (MPT) because airflow rate or air leakage is greater than people without voice disorders. Also they can appear a problem in the intensity regulation. This study analyzed MPT difference based on the comfortable intensity and louder intensity and the correlation between MPT and respiration volume of unilateral vocal fold palsy (UVFP) and sulcus vocalis (SV) group. The twenty with UVFP, the 21 with SV, the 21 normal subjects measured MPT in /a/ vowel prolongation task with comfortable intensity and louder intensity and compared analysis by measuring FVC, FEV1, FEV1/FVC to analyze the correlation between MPT and respiration volume. First, a comparison of MPT according to the intensity between groups is that MPT of the normal group was statistically significant long compared to the patient group in comfortable intensity, but MPT between groups was not statistically significant difference in the louder intensity. Second, an analysis of the correlation between MPT and respiration volume is that this was statistically significant correlation between MPT in comfortable intensity and MPT in louder intensity. But this did not show statistically significant correlation between intensity and respiration volume. This study can be supported the preceding study results deduced that shorting MPT of the patient group compared to the normal group was originated in the problem of laryngeal valving mechanism at the level of vocal folds rather than a problem of respiratory function. Also at the phonation by varying the intensity, the result can deduce that in the case of patient group, the length of MPT had been improved by increasing the glottal closure ratio in the louder intensity. These results can support the theoretical basis that should be applied to the clinicians by varying the intensity at the voice evaluation and voice therapy for the patients with the glottis incompetence.