• 제목/요약/키워드: Smooth area

검색결과 468건 처리시간 0.021초

SAXS와 AFM에 의한 HF-용액내 양극 에칭에 의해 제조된 기공성 실리콘의 구조연구 (SAXS and AFM Study on Porous Silicon Prepared by Anodic Etching in HF-based Solution)

  • 김유진;김화중
    • 한국전기전자재료학회논문지
    • /
    • 제17권11호
    • /
    • pp.1218-1223
    • /
    • 2004
  • Porous silicon materials have been shown to have bright prospects for applications in light emitting, solar cell, as well as light- and chemical-sensing devices. In this report, structures of porous silicon prepared by anodic etching in HF-based solution with various etching times were studied in detail by Atomic Force Microscopy and Small Angle X -ray Scattering technique using the high energy beam line at Pohang Light Source in Korea. The results showed the coexistence of the various pores with nanometer and submicrometer scales. For nanameter size pores, the mixed ones with two different shapes were identified: the larger ones in cylindrical shape and the smaller ones in spherical shape. Volume fractions of the cylindrical and the spherical pores were about equal and remained unchanged at all etching times investigated. On the whole uniform values of the specific surface area and of the size parameters of the pores were observed except for the larger specific surface area for the sample with the short etching time. The results implies that etching process causes the inner surfaces to become smoother while new pores are being generated. In all SAXS data at large Q vectors, Porod slope of -4 was observed, which supports the fact that the pores have smooth surfaces.

경질양극산화된 5083-H321 알루미늄 합금의 해수 내 액적충격침식부식 손상 연구 (Investigation of Liquid Droplet Impingement Erosion Corrosion based on the Flow Rate of Anodized 5083-H321 Al Alloy in Seawater)

  • 신동호;김성종
    • Corrosion Science and Technology
    • /
    • 제19권6호
    • /
    • pp.310-317
    • /
    • 2020
  • This study investigated the damage to the specimen due to liquid droplet impingement erosion corrosion, which improved the corrosion resistance and durability via hard anodization of 5083-H321 aluminum alloy, which is widely used for small ships and marine structures. The experiment combined liquid droplet impingement erosion and electrochemical equipment with the flow rates in natural seawater solution. Subsequently, Tafel extrapolation of polarization curves was performed to evaluate damage due to the liquid droplet impingement erosion corrosion. The damaged surface was observed using a 3D microscope and a scanning electron microscope. The degree of pitting damage was measured using the Image J program, and the surface hardness was measured using the micro-Vickers hardness tester. The corrosion current density, area, depth, and ratio of the damaged areas increased with the increase in flow rate. The grain size of the damaged area at a flow rate of 20 m s-1 showed fewer and minor differences in height, and a smooth curved shape. The hardness of the damaged surface tended to decrease with increase in flow rate.

A Study on the Actual Utilization Status of Public Cremation Facilities in Each Metropolitan City by Citizens in the Jurisdiction Area and out of the Jurisdiction Area with the Use of e-Haneul Funeral Information System

  • Choi, Jae-sil;Kim, Jeong-lae
    • International journal of advanced smart convergence
    • /
    • 제8권4호
    • /
    • pp.121-129
    • /
    • 2019
  • We are based on the results of this study, the policy measures for improving the efficiency of supply & demand policy of public cremation facilities in six metropolitan cities in the whole nation could be suggested as follows. First, when the utilization rate of public cremation facilities by citizents out of the jurisdiction area was lower, the overall demand for cremation was high. Therefore, the supply & demand policy of public cremation facilities should be carried forward by preferentially focusing on Busan Metropolitan City(4.1%) and Daegu Metropolitan City(17.9%) with low utilization rate by citizens out of the jurisdiction area. Second, the utilization variance of public cremation facilities in the whole six metropolitan cities in the whole nation, was insignificant(1.4%). Therefore, for the efficiency of supply & demand policy of cremation facilities in those six metropolitan cities, the customized-policies considering the characteristics of each metropolitan city should be carried forward in priority. Third, on the basis of 2018, the population size of those six metropolitan cities in the whole nation is from minimum 1.15million to maximum 3.39million as a large city, and relatively, they are facing many difficulties in the expansion for supply & demand of cremation facilities. Therefore, for the smooth construction of cremation facilities, it would be necessary to enforce policies that could disperse the demand for cremation through the joint construction of cremation facilities with other local governments close to each metropolitan city.

종합병원 설비집약적인 부문의 리모델링 방안에 관한 연구 - 중앙진료부와 공급부를 중심으로 - (A Study on the Remodeling Strategy for the Equipment Intensive Areas of General Hospitals - Focused on the Diagnosis/Treatment Areas, the Supply Areas -)

  • 김하진
    • 한국실내디자인학회논문집
    • /
    • 제14권1호
    • /
    • pp.100-108
    • /
    • 2005
  • If remodeling is defined as activities that restore the overall function of a building up to the standards currently demanded rather than as a simple replacement or repair of old facilities and equipment, the main task of remodeling should be the reduction in differences between areas, establishment of a functional linkage between departments and setup of a smooth circulation system. Therefore, this study is an analysis of remodeling strategies and construction processes to resolve major tasks of remodeling. Through this research we acquire concluding remarks. 1) The remodeling strategies of equipment-intensive areas can be divided into two measures: utilizing the existing buildings (the main buildings) the most, and of concentrated relocation in the new buildings. The former method is advantageous in that the main building serves as a center in hospital layouts because concentrated placement of the diagnosis/ treatment area and the supply area benefit the overall operation in terms of functions. However, the measure has limits in that it is difficult to install the facilities and equipment of the new demands due to the low ceilings, which serve as a potential challenge in future growth and changes. 2) The latter measure is the one in which equipment-intensive areas and the areas that are absolutely short of space are first placed in the new buildings while other areas (the outpatient area, the administration area and the miscellaneous areas) are in the existing building (main building). Given the possibility of development In the future, concentrated placement in the new buildings can be said to be more effective order to actively address future growth and changes.

상호혼합에 의한 메로시아닌 색소 단분자막의 2차원 거동 및 J-회합체 형성 (Two-Dimensional Behavior and J-Aggregate Formation of Merocyanine Dye Monolayers in Mutual Mixing)

  • 신훈규
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제51권3호
    • /
    • pp.105-110
    • /
    • 2002
  • J-aggregates in the mutual mixing LB films of [6Me-DS]$_{1-x}$ [DO]$_{x}$,[DS]$_{1-x}$ [DO]$_{x}$ and [DSe]$_{1-x}$ [DO]$_{x}$ have been studied by optical absorption, fluorescence and surface pressure-area isotherms. In [6Me-DS]$_{1-x}$ [DO]$_{x}$ films, sharp J-band absorption and fluorescence of [6Me-DS] are linearly shifted to the longer wavelength for the replacement of [6Me-DS] by [DO]. According to the x, a smooth shift of the limited area has been cleared. In the [DS]-[DO] system, the J-band is enhanced at 1:1 composition and strong fluorescence is also observed. Also, the presence of phase separation was suggested in the [DSe]-[DO] system, because the absorption spectra were decomposed into [DSe] and [DO] spectra. On the other hand, in the pressure-area isothermal study, reduction in the molecular occupying area of monolayers has been clarified. This could be ascribed to the enhancement of molecular ordering in J-aggregates. These facts are also believed to reflect the most closely packed arrangement of chromophores in the merocyanine dye monolayers. Thus, it was confirmed that the interaction between mixed dye molecules and the CdC1$_2$+KHCO$_3$subphases affected the J-aggregates of the LB films. Also. it is thought that the J-aggregates are formed non-dimensionally in LB films, such as solution synthesized [DX:DO] assemblies on mixing.s on mixing.

도심지역과 농촌지역의 보건소 이용 만족도에 관한 융합연구 (The Convergence Study about Use Satisfaction of Public Health Center in Urban Areas and Rural Areas)

  • 이보우;이영주;장선주;김창규
    • 한국융합학회논문지
    • /
    • 제10권12호
    • /
    • pp.123-128
    • /
    • 2019
  • 이 연구는 경상북도 G시의 지역주민 409명을 대상으로 도심지역과 농촌지역으로 구분하여 보건소 이용에 대한 만족도와 지역주민에게 필요한 건강사업을 분석하기 위하여 설문조사를 실시하였다. 409명의 대상자 중 보건소를 이용한 경험이 있는 284명을 대상으로 보건소 진료에 관한 만족도를 분석하였으며, 일반진료, 한방진료, 치과진료, 물리치료, 검사, 예방접종 등 모든 분야에서 농촌지역의 만족도가 현저히 낮게 나타났다. 이를 개선하기 위하여 지역주민에게 원활한 공공의료서비스가 제공 될 수 있도록 시설 확충 및 개선이 필요하며, 도심지역과 농촌지역 간의 의료 불평등 해소를 위한 보건의료정책을 펼쳐나가야 할 것 이다.

FEEDING SYSTEM OF LARGE RUMINANTS IN RURAL BANGLADESH

  • Rahman, M.M.;Islam, M.R.;Rahman, M.M.;Zaman, M.A.;Malek, M.A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제5권2호
    • /
    • pp.349-355
    • /
    • 1992
  • In order to explore feeding practices of large ruminants and methods followed in the rural areas, an exploratory survey was made during the period from January 1988 to January 1989 in eight different agro-ecological areas of Bangladesh in relation to the existing seasons and farmers' categories. The study shows what feeding practices varied (p<0.01) from area to area and season to season but not with the farmers' category. Considering the overall picture of feeding practices existing in the country, it can be observed that bigger proportion of farmers practiced stall feeding and tethering ($38.4{\pm}35.1$) followed by stall fed ($34.3{\pm}35.2$) and grazing or tethering ($17.3{\pm}26.7$). The figure with wider deviations indicates that farmers in the rural areas did not follow a smooth feeding practice, the system is rather a complex, heterogenous and a mere consequence of existing land use system. The results of feeding methods of by-product concentrates indicate that it also varied (p<0.01) from area to area but however, not with seasons and farmers' category. It is observed that bigger proportion of farmers fed concentrates to their animals mixed with water ($74.1{\pm}30.3$) followed by mixed with roughage and water ($10.3{\pm}13.3$) or fed alone ($5.6{\pm}14.2$). The method like feeding practice is also complex and heterogenous in the rural areas of Bangladesh. Hence, it is needed to develop a strategic feeding system and method identifying the problems associated with those.

세대별 QLF 기기의 평활면 비와동형 법랑질 우식 병소 탐지에 관한 진단정확도 비교 (Comparison of fluorescence loss measurements among various generations of QLF devices)

  • 박석우;이형석;김상겸;이은송;;김백일
    • 대한치과의사협회지
    • /
    • 제56권1호
    • /
    • pp.8-16
    • /
    • 2018
  • Purpose: The aim of in vitro study was to compare the diagnostic accuracy to detect non-cavitated enamel caries on smooth surface by using four kinds of the QLF devices. Materials and Methods: A total of 52 human permanent premolars and molars were used. Fluorescence images were captured by the QLF devices (Inspektor Pro, QLF-D, Qraycam, and Qraypen). Fluorescence loss of the QLF was calculated. The severity of lesions was categorized into the following 3 scores using polarized light microscopy: normal (S), enamel demineralization to outer half of enamel (D1), and inner half of the enamel up to the dentin-enamel junction (D2). The Kruskal-Wallis test was used to compare the fluorescence loss among the QLF devices. Spearman rank correlation coefficient between histological scores and fluorescence loss of the devices was calculated. The sensitivity, specificity, and area under the receiver operating curve (AUROC) were calculated to compare their diagnostic accuracies. Results: The correlation coefficients between histological scores and the fluorescence loss of the devices showed 0.77 to 0.81 (P < 0.001). All histological scores, the fluorescence loss among the devices showed no statistical difference. Among the devices, sensitivity, specificity, and AUC values of the fluorescence loss showed 0.84 to 0.94, 0.76 to 0.90, and 0.90 to 0.92, respectively. Conclusions: All QLF devices had no difference with excellent diagnostic accuracies to detect non-cavitated enamel caries on smooth surface.

  • PDF

상악동에 발생한 평활근 육종의 치험례 (LEIOMYOSARCOMA OF THE MAXILLARY SINUS : A CASE REPORT)

  • 최세경;김재영;김소미;김현우;남정우;남웅;차인호;김형준
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • 제35권6호
    • /
    • pp.490-493
    • /
    • 2009
  • Leiomyosarcoma(LMS) is a malignant neoplasm of smooth muscle origin, which accounts for 7 % of all soft tissue sarcomas. The most common sites are the gastrointestinal tract and female genital tract. In contrast, primary LMS of the oral and maxillofacial area is rare due to the paucity of smooth muscle in this region. Especially, LMS of the paranasal sinuses is very rare and has an aggressive clinical behavior. Only 28 cases have been described in the english literature, and of these, only 3 patients treated with surgery had a disease-free survival. A 46-year-old woman came to our department for the evaluation of pain on right midface. After a diagnostic work-up, the lesion was diagnosed as LMS of the right maxillary sinus. The radical surgery was done and chemotherapy combined radiotherapy was followed from post operation 1 month. The patient was disease free at post-operation 1 year. We will report this case with literature review.

석창포에 의한 발기부전 개선 효과 (Effect of Acorus Gramineus on the Relaxation of Corpus Cavernosum Smooth Muscle)

  • 리향;김호태;이재윤;이윤정;신홍균;강대길;이호섭
    • 동의생리병리학회지
    • /
    • 제25권5호
    • /
    • pp.863-869
    • /
    • 2011
  • The aim of the present study is to investigate whether an ethanol extract of Acorus gramineus Soland (EAG) augments penile erection in vitro and in vivo experiment. Preconstructed with phenylephrine (PE) in isolated endothelium-intact rabbit corpus cavernosum, EAG relaxed penile smooth muscle in a dose-dependent manner, which was inhibited by pretreatment with NG-nitro-L-argininemethylester (L-NAME), a nitricoxide synthase inhibitor, and 1H-[1,2,4]-oxadiazole-[4,3-${\alpha}$]-quinoxalin-1-one (ODQ), a soluble guanylylcyclase (sGC) inhibitor, respectively. EAG-induced relaxation was significantly attenuated by pretreatment with tetraethylammonium (TEA), a nonselective $K^+$ channel blocker. EAG increased cGMP levels of the rabbit corpus cavernosum in a concentration-dependent manner without changes in cAMP levels. In addition, EAG caused increase of peak intracavernous pressure (ICP), ICP/MAP ratio and area under the carve (AUC) in SD rats. Taken together, these results suggest that EAG augments penile erection via NO-cGMP system and $K^+$ channels in corpus cavernosum.