• 한국전산구조공학회논문집
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• 제36권6호
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• pp.381-389
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• 2023

BIM에서 가장 중요한 요소 중의 하나가 디지털 데이터이다. 체계적인 디지털 데이터 관리를 위해 최근까지 연구를 통해 객체분류체계(OBS)와 속성분류체계(Pset)가 제시되어 왔다. 특히 공정 및 기성 관리에 사용되는 디지털 데이터는 WBS와 CBS로 나뉘고 이를 BIM 객체와 매핑하려면 CBS의 수량 분개가 필요한데 CBS는 양이 매우 방대하고 공종이나 규격, 명칭 및 CBS 코드가 발주처마다 상이하여 WBS나 BIM 모델에 맞는 수량 분개 작업을 엑셀 등을 이용해서 수작업으로 한다는 것은 사실상 어렵다. 이러한 문제점을 극복하기 위해 BIM 모델에 의해 산출하기 힘든 수량 중에서 대부분을 차지하는 연장에 근거한 수량의 전체분을 분개하는 방안, 축적된 WBS-CBS 이력으로부터 최적 CBS를 도출하는 방안과 합리적인 CBS 데이터베이스 구축을 위해 필수적인 CBS 코드 통합 표준화 방안을 제시하였다.

• 대한환경공학회지
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• 제33권6호
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• pp.453-479
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• 2011

오늘날 전세계적으로 수환경에서의 잔류 의약물질들의 오염에 대한 연구결과들이 많이 보고되고 있다. 이들 잔류 의약물질들은 다양한 종류와 그들이 가지는 물리 화학적인 특성들로 인해 수환경에서의 거동, 오염현황, 영향 및 독성 등도 매우 다양하여 수환경 및 수처리 공정에서의 거동을 예측 평가하기가 어렵다. 선진 외국의 경우 환경 중에서의 오염 현황 및 사용량을 정량화하기 위한 조사를 이미 시작하였고, 잔류 의약물질들의 인체에 대한 잠재적 위험성뿐만 아니라 상수나 하수처리 공정에서의 제거기술에 관한 다양한 연구도 활발히 진행하고 있다. 그러나 국내의 경우 잔류 의약물질들에 대해 전국 주요하천과 상수원에 대한 모니터링 결과도 매우 부족한 실정이다. 우선 국내의 경우는 상수원으로 이용되는 전국 주요 하천과 호소에 대해 주기적이고 체계적인 오염현황 평가가 선행되어야 하며, 잔류 의약물질들이 비교적 고농도로 검출되는 상수원에 대해서는 주오염원에 대한 조사도 병행되어야 한다. 또한, 의약물질 사용량은 지속적으로 증가할 것으로 전망되기 때문에 하수처리 시설에 대한 부하도 지속적으로 증가할 것이다. 따라서 수환경에서의 유해도를 저감시키기 위해 효과적인 하수처리 공법의 도입이 절실하며, 상수에 대한 안전성 확보를 위해서도 잔류 의약물질들의 수환경중에서의 물리 화학적 거동에 대한 면밀한 연구가 요구된다.

• 한국산업보건학회지
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• 제23권3호
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• pp.169-176
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• 2013

Objectives: The aim of this study is to critically review the health effects of not only direct exposure to biocide, but also indirect exposure to by-product hazardous agents generated through the use of biocide in metalworking operations. Methods: An extensive literature review was conducted of studies reporting on respiratory disease cases, particularly hypersensitivity pneumonitis (HP), in environments using water-soluble metalworking fluids (MWFs). Keyword search terms included 'metalworking fluids', 'machining fluids', 'metalworking operation' 'machining operation' and 'biocide', which were also used in combination. Additional articles were identified in references cited in the articles reviewed. Results: Several of the field, epidemiological and experimental studies reviewed assumed that the symptoms and signs typical of HP developed in machinists who handled water-soluble MWF could be caused by inhalation exposure to nontuberculous mycobacteria (NTM). Most NTM are known to be not only resistant to both biocide and disinfectant, but also to have acid-fast cell walls that are highly antigenic. The presence or persistence of the Mycobacterium species, referred to as NTM, in metalworking fluid-using operations may be caused by NTM contamination in either the natural water or tap water that is used to dilute the base oil and additives for water-soluble MWFs. This hypothesis that NTM contamination in water-soluble MWFs is a causative agent of HP has high biologic plausibility, such as antigenic property, hydrophobicity and small diameter (< 5 um). Conclusions: Aerosolized mycobacteria colonized from MWF are likely to be causing the HP. Inhalation exposure to mycobacteria should be considered as a possible cause for the development of HP.

• 대한가정학회지
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• 제50권7호
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• pp.67-79
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• 2012

This study analyzed the characteristics of morphing in fashion design through the documentaries on morphing and fashion. The characteristics of morphing in fine art, media, and design area were categorized as reversible metamorphosis, sequential dissolve and blurring of interpolation boundaries. The results were as follow in fashion design. Reversible metamorphosis showed an automatic silhouette transformation by remote control, the metamorphosis of folding method by wearer's own movements and the automatic silhouette transformation by the air pressurizing method. It represented the thoughts of omnipotence as in the feeling of the magical world, the human desire for control in life, the rationalization of magical thinking and imaginative power, the creation of a new dress space and the extension of dress function. Sequential dissolve showed juxtaposition in the same area by the time order, juxtaposition in virtual space through the computer graphics, the series of fashion photography by steel cut of the dress making process and the blending of digital film and fashion design. It represented the approach for the storytelling of fashion show, implication of creative fashion design process and the creation of organic forms and the feeling of fantasy through artificial technology. The blurring of interpolation boundary showed an overlay of different fabrics with transparent boundaries, an overlay of different patterns with transparent boundaries and the blending of fabrics through the visual mixing of color. It represented the obfuscation of the object, the connotation of the space order, the connotation of the extensive and various meanings and the integrative property of objects.

• 대한기계학회논문집
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• 제17권5호
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• pp.1227-1236
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• 1993

본 연구에서는 또하나의 새로운 서술방식을 제시하게 되는데, 먼저 에너지 이동현상으로서의 일중에서 가용일을 분리하고, 가역과정만이 가능한 세계 즉 가역세 계 안에서 측정과 산정이 가능하도록 열역학의 가장 중요한 물리량인 온도와 엔트로피, 열 등을, 가용일의 가측성을 이용하여 정의한 다음, 그러한 제한조건하에서 기존 열역 학의 기본 법칙들이 어떻게 표시되는가 살펴보고, 이것을 비가역과정에 확장하는 식의 순서에 따라 열역학의 기존원리들에 대한 서술을 재구성하고자 한다.

• 전기화학회지
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• 제3권2호
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• pp.72-75
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• 2000

For the purpose of developing the non-stoichiometric Zr-based Laves phase alloy with higher capacity and better performance for electrochemical application, extensive work has been carried out in KAIST. After careful alloy design of $ZrMn_2-based$ hydrogen storage alloys through varing their stoichiometry while susbstituting or adding some alloying elements, the $Zr-Ti-(Lh-V-Ni)_{2.2},\;Zr-Ti-(Mn-V-Cr-Ni)_{1.8\pm0.1}$ with high capacity and better performance was developed. Consequently the $Zr-Ti-(Mn-V-Ni)_{2.2}$ alloy has a high discharge capacity of 394mAh/g and shows a high rate capability equaling to that of commercialized $AB_5$ type alloys. On the other hand, in order to develop the hydrogen storage alloy with higher discharge capacity, the hypo-stoichiometric $Zr(Mn-V-Ni)_{2-\alpha}$ alloys substituted by Ti are under developing. As the result of competitive roles of Ti and $stocihiometry({\alpha})$, the discharge capacity of $Zr-Ti-(Mn-V-Cr-Ni)_{l.8\pm0.1}$ alloys is about 400mAh/g(410 mAh/g, which shows the highest level of performance in the Zr-based alloy developed. Our sequential endeavor is improving the shortcoming of Zr-based Laves phase alloy for commercialization, i.e., poor activation property and low rate capability, etc. It is therefore believed that the commercialization of Zr-based Laves phase hydrogen storage alloy for Ni-MH rechargeable battery is in near future.

• Journal of Welding and Joining
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• 제30권2호
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• pp.65-69
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• 2012

Environmental and health concerns over the lead have led to investigation of the alternative Pb-free solders to replace commonly used Pb-Sn solders in microelectronic packaging application. The leading candidates for lead-free solder alloys are presently the near eutectic Sn-Ag-Cu alloys. Therefore, extensive studies on reliability related with the composition have been reported. However, the insufficient drop property of the near eutectic Sn-Ag-Cu alloys has demanded solder compositions of low Ag content. In addition, the solder interconnections in automobile applications like a smart box require significantly improved vibration resistance. Therefore, this study investigated the effect of alloying elements (Ag, Bi, In) on the vibration fatigue strength. The vibration fatigue was conducted in 10~1000Hz frequency and 20Grms. The interface of the as-soldered cross section close to the Cu pad indicated the intermetallic compound ($Cu_6Sn_5$) regardless of solder composition. The type and thickness of IMC was not significantly changed after the vibration test. It indicates that no thermal activities occurred significantly during vibration. Furthermore, as a function of alloying composition, the vibration crack path was investigated with a focus on the IMCs. Vibration crack was initiated from the fillet surface of the heel for QFP parts and from the plating layer of chip parts. Regardless of the solder composition, the crack during a vibration test was propagated as same as that during a thermal fatigue test.

• 한국정보과학회논문지:정보통신
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• 제31권1호
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• pp.27-36
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• 2004

사용자의 이동성을 지원하는 Mobile IP 환경에서, 빈번한 바인딩 갱신 메시지의 발생은 상당한 부하를 초래할 수 있다. 따라서 이를 감소시키기 위한 알고리즘 개발이 필요하다. 이를 위해, 본 논문에서는 사용자의 이동성과 관련된 지역적 특성을 고려한 동적 바인딩 갱신을 위한 라이프타임 할당 기법을 제안한다. 각 이동 노드는 방문한 서브넷과 관련된 로그 정보를 이용하여 프로파일을 유지하고 있다. 즉, 방문한 서브넷별로 평균 상주시간을 기반으로 하여 적응적 라이프타임을 결정하여 다음 방문 시에 이 값을 바인딩 갱신의 라이프타임으로 사용한다. 또한 각 이동 노드가 동일한 서브넷을 방문하더라도 방문 시간대에 따라 평균 상주시간이 차이가 날 수 있다는 사실을 기반으로 하여, 동일한 서브넷에 대하여 방문 시각에 따라 별개의 라이프타임을 결정하는 알고리즘도 제안한다. 제안한 기법의 성능 향상을 보이기 위하여 기존 Mobile IPv6과 비교 실험을 수행하였으며, 이 과정에서 다음의 두 가지 인자를 주로 비교하였다: 바인딩 갱신 메시지의 수 및 바인딩 요청 메시지의 수. 실험 결과, 제안한 기법은 기존 Mobile IPv6에 비해 위 메시지의 수를 줄임으로써 상당한 통신비용 절감효과를 보여주었다.

• Journal of Microbiology and Biotechnology
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• 제21권2호
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• pp.147-153
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• 2011

Bacillus species have been involved in metal association as biosorbents, but there is not a clear understanding of this chelating property. In order to evaluate this metal chelating capacity, cultures and spores from Grampositive bacteria of species either able or unable to produce surface layer proteins (S-layers) were analyzed for their capacity of copper biosorption. Only those endowed of S-layers, like Bacillus sphaericus and B. thuringiensis, showed a significant biosorption capacity. This capacity (nearly 50%) was retained after heating of cultures, thus supporting that structural elements of the envelopes are responsible for such activity. Purified S-layers from two Bacillus sphaericus strains had the ability to biosorb copper. Copper biosorption parameters were determined for strain B. sphaericus 2362, and after analyses by means of the Langmuir model, the affinity and capacity were shown to be comparable to other bacterial biosorbents. A competitive effect of $Ca^{2+}$ and $Zn^{2+}$, but not of $Cd^{2+}$, was also observed, thus indicating that other cations may be biosorbed by this protein. Spores that have been shown to be proficient for copper biosorption were further analyzed for the presence of S-layer content. The retention of S-layers by these spores was clearly observed, and after extensive treatment to eliminate the S-layers, the biosorption capacity of these spores was significantly reduced. For the first time, a direct correlation between S-layer protein content and metal biosorption capacity is shown. This capacity is linked to the retention of S-layer proteins attached to Bacillus spores and cells.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8563-8566
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• 2016

Colorectal cancer is one of the most common lethal cancer types worldwide. In recent years, widespread and large-scale studies have been done on medicinal plants for anti-cancer effects, including Glycyrrhiza glabra. The aim of this study was to evaluate the effects of an ethanol extract Glycyrrhiza glabra on the expression of HSP90, growth and apoptosis in the HT-29 colon cancer cell line. HT-29 cells were treated with different concentrations of extract (50,100,150, and $200{\mu}g/ml$). For evaluation of cell proliferation and apoptosis, we used MTT assay and flow cytometry technique, respectively. RT-PCR was also carried out to evaluate the expression levels of HSP90 genes. Results showed that Glycyrrhiza glabra inhibited proliferation of the HT-29 cell line at a concentration of $200{\mu}g/ml$ and this was confirmed by the highest rate of cell death as measured by trypan blue and MTT assays. RT-PCR results showed down-regulation of HSP90 gene expression which implied an ability of Glycyrrhiza glabra to induce apoptosis in HT-29 cells and confirmed its anticancer property. Further studies are required to evaluate effects of the extract on other genes and also it is necessary to make an extensive in vivo biological evaluation and subsequently proceed with clinical evaluations.