• Animal cells and systems
• /
• 제2권1호
• /
• pp.145-152
• /
• 1998

The spinning apparatus and production of secretory silk from silk gland of the black widow spider, Latrodectus mactans were studied with scanning and transmission electron microscopes. The silk glands were located in seven groups on the spinnerets including each pair of major and minor ampullate, 3 pairs of tubuliform, 1 pair of flagelliform, 2 pairs of aggregate, about 50 pairs of pyriform and over 250 pairs of aciniform glands, respect- ively. Each group of silk gland feeds silk into one of the three spinneret pairs. Secretory silk is synthesized from rough endoplasmic reticulum (rER) of glandular epithelial cells. The secretory silk is transported from toe rER into the secretory vacuoles which are grown up by fusion with the surrounding small vesicles including the secretory silk. The secretory vacuoles, which show a gradual increase in electron density with the process of maturity, are formed without involvement of the Golgi complex, suggesting that they do not play an important role in the processing of the secretory silk. The secretory silk products are released by the mechanism of apocrine secretion, losing part of their cytoplasm. Moreover, another type of silk precursor, possibly protein, appears as granular material, and is also discharged to the luminal cavity.

• Journal of Multimedia Information System
• /
• 제2권3호
• /
• pp.255-262
• /
• 2015

The modern manufacturing systems and technologies produce products that are more accurate day by day. This can be reached mainly by improvement the manufacturing process with at the same time restricting more and more the quality specifications and reducing the uncertainty in part. The main objective an industry becomes to lower the part's variability, since the less variability - the better is product. One of the part of this task is measuring the object's uncertainty. The main purpose of this study is to understand the application of bootstrap method for uncertainty evaluation. Bootstrap method is a collection of sample re-use techniques designed to estimate standard errors and confidence intervals. In the case study a surface of an automobile engine block - (Top view side) is measured by Coordinate Measuring Machine (CMM) and analyzed for uncertainty using Geometric Least Squares in complex with bootstrap method. The designed experiment is composed by three similar measurements (the same features in unique reference system), but with different points (5, 10, 20) concentration at each level. Then each cloud of points was independently analyzed by means of non-linear Least Squares, after estimated results have been reported. A MatLAB software tool used to generate new samples using bootstrap function. The results of the designed experiment are summarized and show that the bootstrap method provides the possibility to evaluate the uncertainty without repeating the Coordinate Measuring Machine (CMM) measurements many times, i.e. potentially can reduce the measuring time.

• Animal cells and systems
• /
• 제12권2호
• /
• pp.109-116
• /
• 2008

Among the four kinds of silk glands in the funnel-web spider Agelena limbata, the ampullate gland for dragline silk production is the most predominate one in both sexes, and is composed of three functional parts-excretory duct, storage ampulla and convoluted tail regions. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another two pairs of minor ampullate glands supply the middle spinnerets. There are no apparent differences between the major and minor ampullate glands not only the external spigots but also their internal silk glands. However, the microstructure is very unique in this spider, because each gland has spherical shaped storage sac with twig-like branched tails. Nevertheless, the wall of the secretory region is similarly composed of a single layer of epithelial cells. The mature secretory silks in glandular epithelium are closely packed and accumulated as electron-opaque vesicles. Most of the secretory products which originated from the rough endoplasmic reticula(rER) are grown up by fusion with the surrounding small vesicles however, the Golgi complex does not seem to play an important role in this process of secretion.

• 한국기계가공학회지
• /
• 제20권2호
• /
• pp.45-50
• /
• 2021

In the recent fourth industrial revolution, the demand for additive processes has emerged rapidly in many mechanical industries, including the aircraft and automobile industries. Additive processes, in contrast to subtractive processes, can be used to produce complex-shaped products, such as three-dimensional cooling systems and aircraft parts that are difficult to produce using conventional production technologies. However, the limitations of additive processes include nonuniform surface quality, which necessitates the use of post-processing techniques such as subtractive methods and grinding. This has led to the need for hybrid machines that combine additive and subtractive processes. A hybrid machine uses additional additive and subtractive modules, so product deformation, for instance, deflection, is likely to occur. Therefore, structural analysis and design optimization of hybrid machines are essential because these defects cause multiple problems, such as reduced workpiece precision during processing. In this study, structural analysis was conducted before the development of an additive/subtractive hybrid processing machine. In addition, structural optimization was performed to improve the stability of the hybrid machine.

• 한국산업융합학회 논문집
• /
• 제6권4호
• /
• pp.413-420
• /
• 2003

We can take 'Profit security', in the field Process improvement activity and man-power upgrade in the learning of organization activity or upgrading ability of each peoples. After Tayler System(Scientific Management in1911) and Ford System(Conveyor system in 1913), Toyota System(Ohno's TPS; Toyota Production System around 1980) which was developed by Toyota in Japan in the third productive revolution. This thesis study on the focus of 2 successful examples(P and S companies in Seong-Seo industrial complex Tae-Gu city) which introduce Toyota system can apply to VM(Visual Management), 3jeong(Right Products Right Quantity, Right Box and Right Position)5S(Seiri, Seiton, Seisoh Seiketsu, Sitsuke), JIT(Just In Time), KAIZEN(Improvement), KANBAN System(Logistic) and output of Factory. For examples P company obtained a lot of results(productivity increase 19%, Quality up 46%-36ppm, storage decrease 25% per year), S company obtained a lot of results(productivity increase 20%, Quality up 40%, storage decrease 33% per year, 2600 improvements in 2002. In conclusion Korean KANBAN system (modified Toyota System) is similar to exchange of work as Korean traditional system in agriculture as like dure 'PUMASHI' SANGBU-SANJO) that's autonomous management systems. In conclusion Korea KANBAN system needs apply to not only all the manufacturing industry but also the various fields of industry.

• 한국멀티미디어학회논문지
• /
• 제12권1호
• /
• pp.122-129
• /
• 2009

레거시 시스템이나 특정 벤더의 애플리케이션이 혼재 되어 있는 기존 IT 환경에서 새로운 기술을 도입한다는 것은 많은 비용과 시간이 소요되는 작업이다. 특히 특정 소프트웨어나 일부 상용 애플리케이션에서 상호 연동성이 높지 않은 경우 이러한 상황이 더 많이 발생하며 시스템 도입 중 예상하지 못하는 상황이 발생할 가능성이 높아 새로운 애플리케이션을 적용하는 시간이 더욱 길어지게 된다. 서비스 지향 아키텍처를 기본으로 인터넷 애플리케이션을 생성하면 연결된 시스템 구성에 대해 유연한 처리 방법과 느슨한 결합을 기반으로 하는 아키텍처를 구현 할 수 있다. 이러한 접근방식은 XML 기반의 Web Service를 활용하여 서비스의 통합과 재사용을 통해 복잡한 처리를 요구하는 인터넷 환경의 워크플로우 모델 개발의 가능성을 살펴보고, 하나의 복잡한 비즈니스 프로세스와 다양한 서비스들이 워크플로우를 통해 재사용 될 수 있는 방법을 제안한다.

• 한국CDE학회논문집
• /
• 제18권6호
• /
• pp.428-438
• /
• 2013

The requirement for high performance visualization of engineering analysis of digital products is increasing since the size of the current analysis problems is more and more complex, which needs high-performance codes as well as high performance computing systems. On the other hand, different companies or customers do not have all the facilities or have difficulties in accessing those computing resources. In this paper, we present a multi-view supporting VR/AR system for providing supercomputing-based engineering analysis services. The proposed system is designed to provide different views supporting VR/AR visualization services depending on the requirement of the customers. It provides a sophisticated VR rendering directly dependent on a supercomputing resource as well as a remotely accessible AR visualization. By providing multi-view centric analysis services, the proposed system can be more easily applied to various customers requiring different levels of high performance computing resources. We will show the scalability and vision of the proposed approach by demonstrating illustrative examples with different levels of complexity.

• 한국시뮬레이션학회논문지
• /
• 제20권3호
• /
• pp.1-10
• /
• 2011

본 연구에서는 반도체, 디스플레이 등과 같은 첨단 전자제품 제조 시스템에서의 공정별 기계 대수를 결정하는 용량계획 문제를 고려한다. 제조 시스템은 공정별로 동일한 병렬기계가 존재하는 혼합흐름공정의 형태를 갖고 있으며, 각 기계 마다 서로 다른 제품 종류를 연속적으로 가공할 때는 셋업 작업이 발생한다. 설비를 구매할 수 있는 예산에 제약이 있는 상황에서 제조시스템의 생산율을 최대화 할 수 있는 공정별 기계 대수 조합을 결정해 주고자 한다. 혼합흐름공정 형태의 복잡한 제조시스템을 대상으로 주문이 동적으로 도착하고 여러 가지 일정계획방법을 적용하는 것을 모델링 하기 위하여 시뮬레이션 모델을 개발하였다. 본 연구에서는 시뮬레이션 실행을 포함한 다양한 조합의 기계 대수 증감 휴리스틱 방법을 제안하여 해를 도출하였다. 제안된 방법들은 일련의 계산실험을 통하여 그 성능을 비교 평가하였다.

• 대한기계학회논문집A
• /
• 제39권9호
• /
• pp.871-877
• /
• 2015

다양한 기계부품과 센서류가 포함된 수중로봇, 무인 잠수정 등과 같은 심해장비 시스템은 수심에 따른 높은 수압과 온도, 조류 등 심해의 복합적인 극한 환경조건의 영향을 받기 때문에 실제 현장에서 사용되기 전에 제품의 신뢰성을 검증하는 것이 매우 중요하다. 이러한 복합적인 해양환경을 재현하여 제품에 대한 실증적인 시험을 할 수 있는 시험장비의 구축이 요구되는 실정이다. 본 연구를 통하여 최대수압 2.0MPa, 수온 $5{\sim}60^{\circ}C$, 최대유속 2 m/s의 복합 환경조건의 구현이 가능한 워크인 타입의 수중복합 환경시험장비를 구성하는 주요 구성품의 개발 요구사양 및 설계방안을 제시하고 이를 통해 심해장비 시스템 및 모듈 부품에 대한 제품 신뢰도를 검증할 수 있는 시험장비의 개발 내용을 제시하고자 한다.

• 지능정보연구
• /
• 제27권2호
• /
• pp.1-15
• /
• 2021

추천시스템은 사용자의 기호를 파악하여 물품 구매 결정을 도와주는 역할을 할 뿐만 아니라, 비즈니스 전략의 관점에서도 중요한 역할을 하기에 많은 기업과 기관에서 관심을 갖고 있다. 최근에는 다양한 추천시스템 연구 중에서도 NLP와 딥러닝 등을 결합한 하이브리드 추천시스템 연구가 증가하고 있다. NLP를 이용한 감성분석은 사용자 리뷰 데이터가 증가함에 따라 2000년대 중반부터 활용되기 시작하였지만, 기계학습 기반 텍스트 분류를 통해서는 텍스트의 특성을 완전히 고려하기 어렵기 때문에 리뷰의 정보를 식별하기 어려운 단점을 갖고 있다. 본 연구에서는 기계학습의 단점을 보완하기 위하여 BERT 기반 감성분석을 활용한 추천시스템을 제안하고자 한다. 비교 모형은 Naive-CF(collaborative filtering), SVD(singular value decomposition)-CF, MF(matrix factorization)-CF, BPR-MF(Bayesian personalized ranking matrix factorization)-CF, LSTM, CNN-LSTM, GRU(Gated Recurrent Units)를 기반으로 하는 추천 모형이며, 실제 데이터에 대한 분석 결과, BERT를 기반으로 하는 추천시스템의 성과가 가장 우수한 것으로 나타났다.