• Journal of Periodontal and Implant Science
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• 제48권4호
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• pp.202-212
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• 2018

Purpose: Bone-to-implant contact (BIC) is difficult to measure on micro-computed tomography (CT) because of artifacts that hinder accurate differentiation of the bone and implant. This study presents an advanced algorithm for measuring BIC in micro-CT acquisitions using a spiral scanning technique, with improved differentiation of bone and implant materials. Methods: Five sandblasted, large-grit, acid-etched implants were used. Three implants were subjected to surface analysis, and 2 were inserted into a New Zealand white rabbit, with each tibia receiving 1 implant. The rabbit was sacrificed after 28 days. The en bloc specimens were subjected to spiral (SkyScan 1275, Bruker) and round (SkyScan 1172, SkyScan 1275) micro-CT scanning to evaluate differences in the images resulting from the different scanning techniques. The partial volume effect (PVE) was optimized as much as possible. BIC was measured with both round and spiral scanning on the SkyScan 1275, and the results were compared. Results: Compared with the round micro-CT scanning, the spiral scanning showed much clearer images. In addition, the PVE was optimized, which allowed accurate BIC measurements to be made. Round scanning on the SkyScan 1275 resulted in higher BIC measurements than spiral scanning on the same machine; however, the higher measurements on round scanning were confirmed to be false, and were found to be the result of artifacts in the void, rather than bone. Conclusions: The results of this study indicate that spiral scanning can reduce metal artifacts, thereby allowing clear differentiation of bone and implant. Moreover, the PVE, which is a factor that inevitably hinders accurate BIC measurements, was optimized through an advanced algorithm.

• 대한치과교정학회지
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• 제50권6호
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• pp.373-382
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• 2020

Objective: To compare computer-aided design and computer-aided manufacturing (CAD/CAM) customized nitinol retainers with standard stainless-steel fixed retainers over a 12-month study period. Methods: This randomized controlled trial (RCT) was conducted on 62 patients randomly allocated to a control group that received stainless-steel retainers or a test group that received customized CAD/CAM nickel-titanium retainers. Four time points were defined: retainer placement (T0) and 1-month (T1), 6-month (T2), and 12-month (T3) follow-up appointments. At each time point, Little's irregularity index (LII) (primary endpoint) and dental stability measurements such as intercanine width were recorded in addition to assessment of periodontal parameters. Radiological measurements such as the incisor mandibular plane angle (IMPA) were recorded at T0 and T3. Failure events (wire integrity or debonding) were assessed at each time point. Results: From T0 to T3, LII and other dental measurements showed no significant differences between the two groups. The data for periodontal parameters remained stable over the study period, except for the gingival index, which was slightly, but significantly, higher in the test group at T3 (p = 0.039). The IMPA angle showed no intergroup difference. The two groups showed no significant difference in debonding events. Conclusions: This RCT conducted over a 12-month period demonstrated no significant difference between customized CAD/CAM nickel-titanium lingual retainers and standard stainless-steel lingual retainers in terms of dental anterior stability and retainer survival. Both retainers eventually appeared to be equally effective in maintaining periodontal health.

• 한국재난관리표준학회지
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• 제1권2호
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• pp.61-66
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• 2008

국토의 70% 이상이 산지로 구성되어 있어서 도로와 철도 건설을 위해 절토사면이 필연적으로 발생한다 우기, 동절기 서리로 인한 지반융기, 그리고 해빙은 암석 탈락과 사면붕괴의 원인이 되며 매년 사면붕괴에 의한 차량파손과 인명피해가 증가하고 있다. 인명과 재산을 보호하기 위해 사연붕괴를 조기에 탐지할 수 있는 실시간 모니터링 시스템이 필요하다. GMG사에서 개발한 병진 회전 침하(TRS) 센서를 사면 내에 설치하여 실시간으로 사면을 모니터링을 할 수 있도록 했으나, 시스템의 데이터 획득체계가 취약하여 순간적인 낙뢰에 의해 전체 시스템이 손상될 수 있다. 따라서 저자들은 USN(Ubiquitous Sensor Network)을 제시하여 낙뢰에 의한 손상을 최소화시키고 신뢰도 높은 사면 변형 모니터링 체계를 구축했다.

• 한국공간정보시스템학회 논문지
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• 제11권1호
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• pp.195-199
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• 2009

증강현실 기술은 실제 환경에 컴퓨터로부터 생성된 가상 데이터를 실시간으로 덧씌우는 기술을 말하며, 이는 지리정보의 가시화 같은 작업에 매우 큰 잠재력을 갖고 있다. 하지만 지금까지 연구된 이동형 증강현실 시스템은 사용자의 위치를 파악하기 위해 GPS(Global Positioning System)를 사용하거나 마커를 현장에 붙이는 방식을 사용하였다. 최근 연구들은 마커를 사용하지 않는 방법을 지향하고 있으나 많은 제약을 갖고 있다. 특히 실내의 경우는 GPS정보를 사용할 수 없기 때문에 실내 위치파악을 위해서는 좀 더 복잡한 문제들을 해결할 수 있는 새로운 기술이 필요하다. 최근 무선(RF, Radio Frequency)기반의 실내 위치 추정 연구가 활발히 수행되고 있지만, 이 또한 다량의 센서와 인식기를 설치해야한다는 제약이 존재한다. 본 연구에서는 한 대의 카메라를 사용하는 SLAM(Simultaneous Localization and Mapping) 알고리듬을 이용한 위치 추정기법을 제시하였으며, 추정된 위치를 이용하여 증강현실을 통한 정보 가시화 프로그램을 개발하였으며 이를. 향후 실내외 seamless 연동이 가능한 모바일 u-GIS (Ubiquitous Geospatial Information System) 시스템에 적용할 것이다.

• Mass Spectrometry Letters
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• 제7권1호
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• pp.1-11
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• 2016

Various efforts have been developed to improve sample preparation steps, which strongly depend on hands-on processes for accurate and sensitive quantitative proteome analysis. In this study, we carried out heating the sample prior to trypsin digestion using an instrument to improve the tryptic digestion process. The heat shock generated by the system efficiently denatured proteins in the sample and increased the reproducibility in quantitative proteomics based on peptide abundance measurements. To demonstrate the effectiveness of the protocol, three cell lines (A human lung cancer cell line (A549), a human embryonic kidney cell line (HEK293T), and a human colorectal cancer cell line (HCT-116)) were selected and the effect of heat shock was compared to that of normal tryptic digestion processes. The tryptic digests were desalted and analysed by LC-MS/MS, the results showed 57 and 36% increase in the number of identified unique peptides and proteins, respectively, than conventional digestion. Heat shock treated samples showed higher numbers of shorter peptides and peptides with low inter-sample variation among triplicate runs. Quantitative LC-MS/MS analysis of heat shock treated sample yielded peptides with smaller relative error percentage for the triplicate run when the peak areas were compared. Exposure of heat-shock to proteomic samples prior to proteolysis in conventional digestion process can increase the digestion efficiency of trypsin resulting in production of increased number of peptides eventually leading to higher proteome coverage.

• 한국의류학회지
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• 제40권5호
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• pp.936-953
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• 2016

This article surveys the meaning and history of fashion museum exhibitions to understand the characteristics that make a fashion museum exhibition special. It explores dress museology and fashion museology in theory, and practice across a range of international case studies that include the Costume Institute at the Metropolitan Museum of Art in New York, Mode Museum in Antwerp, and the Victoria and Albert Museum in London. In particular, it examines how curatorial intervention has developed the interpretation and display techniques of dress within the context of the museum or gallery as well as how fashion has made museums accessible to diverse audiences. For a specific case study, we review the types and roles of fashion exhibitions organized by the Simone Handbag Museum, Seoul. It is the first handbag-centered fashion museum in the world as well as one of the most representative local fashion museums. The museum collection includes fashionable western handbags from rare specimens of the $15^{th}$ century to the latest bags of the $21^{st}$ century, and presents a history of changing fashion cycles and the major socio-cultural shifts that have profoundly affected women's lives in public spaces. Exhibitions show the perspective to a range of curatorial methodologies and show the innovative approaches towards collections and displays with broader fashion issues such as gender, materialism and technology. The article is to help encourage further scholar discourse between fashion museum exhibitions and fashion museology.

• The Korean Journal of Physiology and Pharmacology
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• 제16권2호
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• pp.113-118
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• 2012

Ginsenosides are low molecular weight glycosides found in ginseng that exhibit neuroprotective effects through inhibition of $N$-methyl-D-aspartic acid (NMDA) receptor channel activity. Ginsenosides, like other natural compounds, are metabolized by gastric juices and intestinal microorganisms to produce ginsenoside metabolites. However, little is known about how ginsenoside metabolites regulate NMDA receptor channel activity. In the present study, we investigated the effects of ginsenoside metabolites, such as compound K (CK), protopanaxadiol (PPD), and protopanaxatriol (PPT), on oocytes that heterologously express the rat NMDA receptor. NMDA receptor-mediated ion current ($I_{NMDA}$) was measured using the 2-electrode voltage clamp technique. In oocytes injected with cRNAs encoding NMDA receptor subunits, PPT, but not CK or PPD, reversibly inhibited $I_{NMDA}$ in a concentration-dependent manner. The $IC_{50}$ for PPT on $I_{NMDA}$ was $48.1{\pm}4.6\;{\mu}M$, was non-competitive with NMDA, and was independent of the membrane holding potential. These results demonstrate the possibility that PPT interacts with the NMDA receptor, although not at the NMDA binding site, and that the inhibitory effects of PPT on $I_{NMDA}$ could be related to ginseng-mediated neuroprotection.

• Environmental Engineering Research
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• 제21권3호
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• pp.291-296
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• 2016

Application of photocatalytic nanoparticles has been recently gaining an increased attention as air purifying material for sustainable urban development. The present work reports the photocatalytic removal of gaseous phase nitrogen oxides ($NO_x$) using $TiO_2$-coated zeolite to be applied as a filter media for the urban green infrastructure such as raingardens. The $TiO_2$-coated zeolite was synthesized by simple wet chemistry method and tested in a continuous-flow photo-reactor for its removal efficiency of $NO_x$ under different conditions of the weight percentage of $TiO_2$ coated on the zeolite, and gas retention time. The removal efficiency of $NO_x$ in general increased as the weight percentage of $TiO_2$ coated on the zeolite increased up to 15-20%. Greater than 90% of $NO_x$ was removed at a retention time of one minute using the $TiO_2$-coated zeolite ($TiO_2$ weight percentage = 20%). Overall, $TiO_2$-coated zeolite showed greater efficiency of $NO_x$ removal compared to $TiO_2$ powder probably by providing additional reaction sites from the porous structure of zeolite. It was presumed that the degradation of $NO_x$ is attributed to both the physical adsorption and photocatalytic oxidation that could simultaneously occur at the catalyst surface.

• Journal of Ginseng Research
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• 제28권4호
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• pp.165-172
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• 2004

Ginseng is traditionally cultivated worldwide in cold continental climates. It is now also being cultivated in maritime environments such as New Zealandis. This paper reports a number of growth and quality parameters for plants grown under those conditions over two growing seasons and the intervening winter dormant period. While shoot biomass peaked mid-summer, in contrast, root biomass peaked late autumn/early winter. Starch, sucrose, fructose, glucose and inositol were detected in the roots. Starch concentrations were highest in early autumn (mean 470 mg $g^{-1}$ dry weight) and lowest in mid spring (218 mg $g^{-1}$ dry weight). Sucrose concentrations were low during early summer until late autumn but increased rapidly with the onset of winter and peaked during mid spring (168 mg $g^{-1}$ dry weight). Fructose and glucose concentrations were similar and peaked in late spring (5.3 and 6.2 mg $g^{-1}$ dry weight). Inositol concentrations peaked in mid summer (1.7 mg $g^{-1}$ dry weight). Starch/sugar ratios were high during summer and autumn and low during winter and spring. Ginsenoside concentrations and profiles showed that the six major ginsenosides, Rgl, Re, Rb1, Rc, Rb2 and Rd, were present, but Rf was absent. Concentrations did not vary with sampling date. The most abundant ginsenosides were Re (15.9 to 17.5 mg $g^{-1}$ dry weight) and Rb1 (10.7 to 18.1 mg $g^{-1}$ dry weight). Combined, they accounted for < $75{\%}$ of total ginsenoside concentrations. Limited taste tests indicated that highest root quality occurred during late autumn, after the shoots had senesced. However, quality could not be related to plant chemistry.

• 골판지포장물류
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• 62호
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• pp.55-64
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• 2005

1856년 7월7일 영국에서 에드워드 찰스 힐리 와 에드워드 엘리스 알렌(Edward Charles Healey & Edward Ellis Allen)에 의해 골판지가 처음 발명되었고, 15년후인 1871년12월19일에 현재의 골판지상자 형태의 특허가 미국의 알버트. L. 존스(Albert. L.Jones)에게 취득된지 130여년이상이 지난 이 시대에는 실로 다양한 분야에서 골판지를 사용하고 있지만, 주 사용분야는 포장산업의 분야이다. 과거에는 포장의 주목적은 첫째 포장 내용물(상품)의 보호 둘째 상품의 운송과 적재 및 취급의 편리성 셋째 상품 구매동기 유발의 순서이었으나 최근에는 첫째와 둘째의 목적은 필수불가결한 것이고 세번째의 상품 구매동기 유발의 목적에 더 큰 비중이 있는 추세이다. 따라서 포장재의 규격은 생산자의 입장에서는 보다 단순해지고 규격화 되는 것이 생산코스트의 절감과 생산성향상의 지름길이지만(그러나 더욱 복잡해지고 비규격화 되는 것이 제품 부가가치가 더 높을 수도 있기 때문에 여기에는 보다 신중한 판단이 필요하다.) 각종 통신기술, 인터넷과 I.T산업의 발달과 더불어 소비자가 언제라도 상품의 다양한 정보에 쉽게 접할 수있는 이 시대에는 다양한 소비계층의 NEED를 모두 만족시켜 줄려고 하는 상품 개발자의 제품설계 및 개발과 판매전략에 의해 더욱 더 상품은 다양해지고 있다.(필자의 판단으로는 앞으로 보다 더 다양해지고 복잡해지고 있는 추세이다.) 즉 다시말하면 이러한 다양한 형태의 포장재의 변화를 수용하여, 가장 높은 가격경쟁력으로, 적시에 가장빠르게 생산하여 공급할 수있는 능력을 갖춘 포장재 제조업자만이 미래에는 적자생존 할 수있다는 결론이다. 더욱이 우리나라의 현실은 대한민국 골판지 포장산업의 특성상 세계적으로 유래가 없는 적은 판매마진(과도한 출혈경쟁으로 인함)으로 인하여, 생산설비만 계속 증설하여 생산량과 규모에 의한 경제성 만으로 수치채산성을 맞추는 형태로 발전하여 왔기 때문에, 각 골판지 생산공장의 수익성은 악화일로로 치닫고 있는 실정이다. 즉 아주 적은 규모의 공장이나 아니면 많은 자금력을 이용한 대형공장만이 수익성을 유지하고 있는 것처럼 보인다.(지금과 같이 시장의 성장이 없는 골판지시징에서 시장의 총규모는 정해진 상태이고, 여기에서 서로 나눠 가지는 형태이므로, 최악의 경우는 어느 한쪽만이 살아 남는 제로섬 게임이 될 수 있으므로, 실제로는 가장 적정한 규모의 공장이 가장수익성이 높다.) 여기에서 필자는 이러한 위기에 처해 있는 우리나라 골판지산업의 생산공장에서 생산성을 저하시켜 제조원가를 높이는 요인들을 살펴보고, 이 요인들 중에서 주된 요인중의 하나인 소로트오다가 더욱 더 많아지고 있는 현실과 다가오는 미래의 상황에 대비해 골판지 공장의 완전자동화(Ubiquitous in Corrugating Factory)에 대비한 가장 효율적인 소로트생산 운영방법에 대해서 집중적으로 이야기 해보고자 한다.