• 대한인간공학회지
• /
• 제30권2호
• /
• pp.339-347
• /
• 2011

Objective: The purpose of this study was to evaluate of various material of pillows by using biomechanical variables such as the cervical stability, head pressure distribution, and muscle activity. Method: Eight subjects participated in the experiment. Three different materials such as polyester sponge, memory foam and the buckwheat shell used for Korean traditional pillow were tested. Electro-goniometer, six channels of electromyography(EMG), ten channels of the head pressure sensors were used to measure the biomechanical responses. Surface electrodes were attached to the right/left semispinals capitis(RSC, LSC), the right/left sternocleidomastoid(RSM, LSM), the right/left upper trapezius(RUT, LUT). The cervical stability was evaluated by the angle deviated from the standing neck position. The head pressure distribution was evaluated by the pressure per unit area recorded on the sensors and the intensity of peak pressure. Electromyography(EMG) data were analyzed by using root mean square(RMS) and mean power frequency(MPF). Results: The buckwheat shell material showed a higher stability in the cervical spine then the other pillows during spine position. In terms of head pressure distribution, the memory form indicated the lowest pressure at supine position, buckwheat shell material indicated the lowest pressure during lying down to side, and polyester cushion recorded the highest pressure at all postures. Conclusion: The buckwheat shell material has a biomechanical advantage to maintain a healthy neck angle and reduce the pressure on the head, which means the buckwheat shell is a potential material for ergonomic pillow design. The pillow with memory form showed second best biomechanical performance in this study. Application: The shape of the buckwheat shell pillow and the characteristics of materials can be used to design the pillow preventing neck pain and cervical disk problems.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2009년도 제38회 동계학술대회 초록집
• /
• pp.448-448
• /
• 2010

Magnetic random access memory (MRAM) has made a prominent progress in memory performance and has brought a bright prospect for the next generation nonvolatile memory technologies due to its excellent advantages. Dry etching process of magnetic thin films is one of the important issues for the magnetic devices such as magnetic tunneling junctions (MTJs) based MRAM. CoFeB is a well-known soft ferromagnetic material, of particular interest for magnetic tunnel junctions (MTJs) and other devices based on tunneling magneto-resistance (TMR), such as spin-transfer-torque MRAM. One particular example is the CoFeB - MgO - CoFeB system, which has already been integrated in MRAM. In all of these applications, knowledge of control over the etching properties of CoFeB is crucial. Recently, transferring the pattern by using milling is a commonly used, although the redeposition of back-sputtered etch products on the sidewalls and the low etch rate of this method are main disadvantages. So the other method which has reported about much higher etch rates of >$50{\AA}/s$ for magnetic multi-layer structures using $Cl_2$/Ar plasmas is proposed. However, the chlorinated etch residues on the sidewalls of the etched features tend to severely corrode the magnetic material. Besides avoiding corrosion, during etching facets format the sidewalls of the mask due to physical sputtering of the mask material. Therefore, in this work, magnetic material such as CoFeB was etched in an ICP etching system using the gases which can be expected to form volatile metallo-organic compounds. As the gases, carbon monoxide (CO) and ammonia ($NH_3$) were used as etching gases to form carbonyl volatiles, and the etched features of CoFeB thin films under by Ta masking material were observed with electron microscopy to confirm etched resolution. And the etch conditions such as bias power, gas combination flow, process pressure, and source power were varied to find out and control the properties of magnetic layer during the process.

• 한국분말재료학회지
• /
• 제23권1호
• /
• pp.8-14
• /
• 2016

A bulk-type Ta material is fabricated using the kinetic spray process and its microstructure and physical properties are investigated. Ta powder with an angular size in the range $9-37{\mu}m$ (purity 99.95%) is sprayed on a Cu plate to form a coating layer. As a result, ~7 mm-sized bulk-type high-density material capable of being used as a sputter material is fabricated. In order to assess the physical properties of the thick coating layer at different locations, the coating material is observed at three different locations (surface, center, and interface). Furthermore, a vacuum heat treatment is applied to the coating material to reduce the variation of physical properties at different locations of the coating material and improve the density. OM, Vickers hardness test, SEM, XRD, and EBSD are implemented for analyzing the microstructure and physical properties. The fabricated Ta coating material produces porosity of 0.11~0.12%, hardness of 311~327 Hv, and minor variations at different locations. In addition, a decrease in the porosity and hardness is observed at different locations upon heat treatment.

• 복식
• /
• 제58권2호
• /
• pp.78-92
• /
• 2008

The mutual relationship between fashion and architecture and the similarities in their form and structure have been continuously debated over the decades, considering that both spheres are objects used in human life. Both spheres bring about the creation of three-dimensional space structures that are completed by the human body and material, based on a design targeted for people. The similarities between fashion and architecture in terms of form and structure have been debated by western architecture scholars focusing on the support that holds the garment's shape, the tailoring of a men's suit and also the material. The debate originates from the discussion of F. Th. Vischer, Kritische Gnge, and Gottfried Semper during the nineteenth century on the similarities between crinoline and the form of architecture and also the similarities between sewing and architecture. However, architects always regarded fashion as the inferior creative process that follows architecture in viewing the relationship between fashion and architecture. During the mid to end of the twentieth century, contrary to previous decades, the sense of fashion in architecture stood out, as an issue and a different approach was taken in discussing architecture that incorporates fashion. Accordingly, in the mid 1990's, architecture scholars such as Deborah Fausch and Mark Wigley began to conduct close observation of the mutual relationship between fashion and architecture from a more equal point of view. Notwithstanding, their point of view was still biased towards architectural standards. Commencing the Millennium, fashion has become the primary work of creation which leads style in all spheres, and under these circumstances this point of view has transferred from architecture to fashion when thinking about relationships between these spheres. The discussion on fashion and architecture form fashion's point of view is currently concentrated on the post 1990's phenomenon and illustrates the environment that is related to architecture. In general, the discussion is limited to determining a work of an individual designer as 'being architectural' when explaining the sculptural form of fashion. Therefore, this research aims to renew the discussion on twentieth century fashion design, which was neglected in any studies on observing architecture and fashion. The aim of this research is to classify the architectural paradigm of twentieth century fashion design and to observe the architectural forms of the respective eras. It is necessary to have a close observation of the architectural paradigm in twentieth century fashion design where support tools such as the crinoline was avoided and the form and functionality of the garment itself was emphasized. I will conduct this research by considering the architectural form shown in fashion as a practical three-dimensional creation that exists in space.

• Steel and Composite Structures
• /
• 제17권4호
• /
• pp.535-548
• /
• 2014

In this paper, the exact closed-form solutions for torsional analysis of heterogeneous magnetostrictive circular cylinder are derived. The cylinder is subjected to the action of a magnetic field produced by a constant longitudinal current density. It is also acted upon by a particular kind of shearing stress at its upper base. The rigidity of the cylinder is graded through its axial direction from one material at the lower base to another material at the upper base. The distributions of circumferential displacement and shear stresses are presented through the radial and axial directions of the cylinder. The influence of the magnetostrictive parameter is discussed. The effects of additional parameters are investigated.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2001년도 춘계학술대회 논문집
• /
• pp.925-929
• /
• 2001

Ultra-abrasives such as diamond and CBN have used to maintain accuracy and form deviation for superalloy etc. This study contains the dry cylindrical grinding of metals with Vitrified-bond CBN wheel and Resinoid-bond CBN wheel. For various conditions of grinding speed, workpiece speed, grinding depth and feed speed of table, the grinding resistance, the surface roughness, and the material removal are measured and discussed.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
• /
• pp.150-154
• /
• 2000

Coloring admixture is used for take color inside and outside of mortar and concrete, differently form pigment and spray paint take color limited surface. In our country, Using the coloring admixture is very slight and regulation is not yet about it. But that is expected the increase with raising the standard of living. Especially it is used to civil structure like dam and seawall for the environment harmony. Then we observe, in this experiment, the effect of coloring admixture on the material properties of color concrete and propose the suitable mix-proportion of color concrete.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
• /
• pp.379-382
• /
• 2006

In this study, an attempt was made to form magnesium oxide layer via aqueous solution route of salt precipitation process. A layer with flake morphology was formed from the process and various dopants were added during the forming process. The films formed were characterized using SEM, XRD, and cathodoluminescence measurement. In addition, the discharge characteristics were evaluated using panel tests. The results indicate that MgO film can be formed via the aqueous solution process successfully, of which characteristics are comparable to those of MgO film formed by e-beam evaporation process.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
• /
• pp.107-107
• /
• 2004

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2010년도 하계학술대회 논문집
• /
• pp.288-288
• /
• 2010

In this study radio rotatiing field is used in order to form the stable reversed field configuration. The experimental study removing the flux conserving ring not so as to conserve toroidal flux, it was found that there occurred a rapid formation of a stable reversed field configuration, in which toroidal flux was increased shaping reversed field configuration and F-$\Theta$ locus traced close to BFM because it started below F value.