• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1918-1919
• /
• 2011

상체 지원 외골격 로봇은 크게 인간의 근력을 보조하는 형태와 인간의 근력을 증강하는 형태가 있다. 여기서는 인간의 근력을 증강하는 외골격 로봇을 중심으로 기술하고자 한다. 이러한 외골격 로봇은 팔의 EMG (Electromyograph;근전도) 신호를 측정하는 방법보다는 손의 힘을 직접 감지하는 방법을 통한 팔꿈치와 어깨의 엑추에이터를 구동하는 방식을 취하는 경향이 있다. 본 논문에서도 후자의 방식을 이용하여 손에 작용하는 힘을 분석하여 외골격 로봇을 움직이는 방식을 취하였다. 손의 힘 중에서도 인간을 중심으로 볼 때 위방향과 전진방향의 힘을 분석하기 위하여 2개의 F/T(Force/Torque) 센서를 사용하였으며 팔을 벌리는 동작은 엑추에이터 없이 자유롭게 동작이 가능하도록 설계하였다. 이러한 위방향 및 전진방향 힘의 크기를 팔꿈치와 어깨의 엑추에이터의 동작으로 바꾸어 인간의 동작을 도울 수 있고 힘을 증폭할 수 있는 외골격 로봇을 설계 제작하였다. F/T 센서는 손의 힘을 전기적 신호로 바꾸어주는 로드셀로 이루어지며 손의 힘을 최대한 잘 반영하기 위한 구조를 고안하였다. F/T 센서의 전기신호는 증폭기를 거쳐서 잡음을 제거한 후에 A/D 변환하여 processor에서 처리되어진다.

• Korean Journal of Environmental Biology
• /
• v.31 no.4
• /
• pp.393-401
• /
• 2013

The objectives of this study were to analyze structures of fish community and the ecological health using a multi-metric fish model, the Index of Biological Integrity (IBI) in the Backje Weir of Geum River during two periods namely before-the-fishkill ($B_f$) and after-the-fishkill ($A_f$). The total number of fish species observed were 32 and among them 10 species (35%) were Korean endemic species. The exotic species observed were 3 which decreased by 0.4% after-the-fishkill ($A_f$). The dominant species were Opsariichthys uncirostris amurensis (13%) at the Bf period and Squalidus japonicus coreanus (17%) at the Af period in the Backje Weir. At after the fishkill ($A_{f-I}$) total biomass was about 10 times lower than the biomass before-the-fishkill ($B_f$). The biomass of Carassius auratus decreased 98% after-the-fishkill and as time passed by the biomass recovered to nearly 100%. Similar decrease in the biomass occurred in the population of Opsariichthys uncirostris amurensis, while Rhinogobius brunneus population increased. According to the structure analysis of fish community, species richness index, evenness index and species diversity index were high but after-the fishkill, the values of indices decreased. Tolerant species (64%) dominated the fish community, and the sensitive species (2%) were rare, indicating the degradation of the ecosystem. According to analysis of the multi-metric model (IBI), the mean model value of the fish community in Backje Weir was estimated as 17.5 indicating a "fair condition".

• Journal of the Korean earth science society
• /
• v.31 no.4
• /
• pp.370-377
• /
• 2010

In this study, we investigated the kinematical properties of the L1521F-IRS in Taurus region using HCN (J=1-0) molecular line. The high resolution mapping has carried out by $5{\times}5$ point observations covering $3.7'{\times}3.7'$ area using a 12-m telescope of Arizona Radio Observatory in Tucsan, USA. L1521F which harbors the faint infrared L1521F-IRS, displayed a strong central concentration of integrated intensity in HCN without serious molecular depletion. It showed a symmetric kinematical structure with the opposite infall motion in either side of the central cores. It is a direct evidence of bipolar outflows in the core of L1521F.

• Journal of Life Science
• /
• v.15 no.2 s.69
• /
• pp.182-185
• /
• 2005

We used the IS1096 transposon to construct Mycobacterium bovis BCG mutants resistant to an antituberculosis drug PA-824 and isolated several different mutants. We identified the locations of the insertions and found that the insertions were at various sites including the genes for the PPE proteins. HPLC analyses of the extracts of these five PPE mutant cells showed that three mutants produced only F0, and intermediate for the synthetic pathway of coenzyme $F^{420}$, and the remaining two neither F0 nor $F^{420}$. These data suggest that the products of these PPE genes are somehow involved in the biosynthesis of the coenzyme $F^{420}$.

• Culinary science and hospitality research
• /
• v.17 no.1
• /
• pp.93-109
• /
• 2011

This study explores the effect of parent-brand attitude on the purchase intention of an extended brand for expanding a foodservice brand and the interaction effect between parent-brand attitude and perceived risk by fit for the purchase intention of an expanded brand using the proof analysis. As a result, the main effects among parent-brand attitude(F(1,295)=12.012, p<0.01), fit(F(1,295)=17,758, p<0.001), perceived risk(F(1,295)=12.570, p<0.01) and the purchase intention of an expanded brand were significant statistically. Also, for the purchase intention of an expanded brand, not only the effect of interactions between parent-brand attitude and perceived risk(F(1,295)=5.782, p<0.05) but the effect of interactions among parent-brand attitude, fit and perceived risk(F(1,295)=6.068, p<0.05) were significant. In addition, there was difference between parent-brand attitude to purchase intention and the interaction effect of perceived risk by the fit of an extended brand.

• Journal of Digital Convergence
• /
• v.20 no.2
• /
• pp.345-351
• /
• 2022

For simple undirected graph G=(V,E), L(2,1)-coloring of G is a nonnegative real-valued function f : V → [0,1,…,k] such that whenever vertices x and y are adjacent in G then |f(x)-f(y)|≥ 2 and whenever the distance between x and y is 2, |f(x)-f(y)|≥ 1. For a given L(2,1)-coloring c of graph G, the c-span is λ(c) = max{|c(v)-c(v)||u,v∈V}. L(2,1)-coloring number λ(G) = min{λ(c)} where the minimum is taken over all L(2,1)-coloring c of graph G. In this paper, based on Harary's Theorem, we use Tabu Search to figure out the existence of Hamiltonian Path in a complementary graph and confirmed that if λ(G) is equal to n(=|V|).

• Proceedings of the ESK Conference
• /
• 1992.10a
• /
• pp.22-25
• /
• 1992

항공산업은 그 특성상 고도의 신뢰성, 안정성이 요구되며, 이를 충족시키기 위하여는 복잡하고 정밀한 구조를 가져야 하므로 다른 산업제품과는 비교가 안될 정도로 그부가가치를 가지고, 타 산업에의 기술 파급 효과가 역시 지대하다. 따라서, 우리나라와 같이 부존자원이 빈약하나 인적 자원이 우수하고 풍부한 나라에서는 자원절약형 산업인 항공산업의 타당성을 검토, 장기적인 육성방안을 수립하여 추진하는 것은 시대적인 요구라 할 수 있다. 이러한 요구에 따라 국방과학연구소에서 공군의 초, 중등훈련기 개발을 추진 중에 있음은 KFP(Korea Fighter Program)사업과 함께 매우 중요한 의미을 갖는다. 이와 같은 시점에서 한국인의 인체특성에 보다 적합한 항공기의 개발은 가장 시급한 과제이며, 이 문제점을 극복하기 위한 기본연구로 조종실 내부설계에 필요한 기준점 및 치수, MIL-SPEC에서 규정하고 있는 기준치를 분석하였으며 실제 항공기(F-5, F-4, F-16)칫수를 측정하여 이를 정면도, 측면도, 평면도로 제시하고, 항공기 제어계통인 조종간, 동력제어기, 러더페달 및 조종석의 실제 측정치와 공군 조종사의 인체측정치를 비교, 평가하였다. 또한 전투기들의 정면 계기판과 좌, 우측의 제어판의 표시장치 및 조작기들을 기능별로 구분하여 각 요소별 제한조건 및 설계지침들을 비교, 분석하였다.

• Horticultural Science & Technology
• /
• v.31 no.3
• /
• pp.328-336
• /
• 2013

This study was conducted to evaluate imported tomato $F_1$ cultivars as breeding materials for the resistance to Tomato yellow leaf curl virus (TYLCV) by molecular markers and bioassay. From marker genotyping and disease evaluation of 40 $F_1$ cultivars, most of the cultivars declared as TYLCV-resistance carried heterozygous marker genotype for the TYLCV resistance genes Ty-1, Ty-3, or Ty-3a, and showed low disease rates. Whereas, 4 of 5 $F_1$ cultivars declared as intermediate resistance showed marker genotype for susceptibility and disease rates ranged 18.1-33.3%. However, the xx cultivars showed inconsistency in marker genotype and disease rate. Characterization of horticultural traits of the $F_1$ cultivars with TYLCV-resistance indicated that large-size fruit cultivars were higher in yield and similar in sugar contents and solid-acid ratio compared to a control cultivar preferred in the domestic market, although hardness remained to be a problem. On the other hand, cherry tomato cultivars showed lower yield and brix, but longer internode compared to a control cultivar, indicating that breeding for TYLCV-resistance using these cultivars will require more efforts and time compared to large-sized.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.25 no.2
• /
• pp.183-190
• /
• 2009

The aim of this study is to find the condition of forming the favorable nanotubes by anodizing with NaF and $H_3PO_4$. Machined Ti discs were used for anode, and Platinum net was used for cathode. For electrolyte, $H_3PO_4$ and NaF solution were mixed. We controlled voltage, electrolyte concentration, anodizing time and formed nanotubes on Ti discs. After that, these were washed with distilled water for 24 hours and dried in the $40^{\circ}C$ oven for 24 hours. The surface structure of specimens were analyzed. The results were as follows : At 0.5 wt % NaF, according as increasing voltage and anodizing time, early state of nucleating pores were generated. At 1.0 wt % NaF, 20 V, 20 & 25 min, well-formed nanotubes were observed. At 1.0 wt % NaF, 30 V, structure of nanotube became bigger and interconnected. At 2.0 wt % NaF, no nanotubes were formed and it was unrelated with voltage and time. At 1.0 wt % NaF, 20 V, 20 - 25 min, well-ordered nanotubes were generated on Ti discs. For the formation of favorable nanotubes, it is considered that proper parameters such as electrolyte concentration, voltage, anodizing time are necessary according to the kind of electrolytes.

• Nuclear Engineering and Technology
• /
• v.6 no.1
• /
• pp.14-22
• /
• 1974

Effects of anodization voltage on frequency characteristics of anodic oxide films on tantalum were analyzed based on the following impedance equatious : (equation omitted) Here $R_{f}$, $C_{f}$ and tan $\delta$$_{f}$ are equivalent series resistance in ohm, equivalent Belies capacitance in farad and dielectric loss, of anodic oxide films respectively Parameters P, $\tau$$_{ο}$, $\tau$$_{\omega}$, and Co are defined as follows: P=(d-w)/w, $\tau$$_{ο}$=$textsc{k}$$\rho$$_{ο}$, $\tau$$_{\omega}$=$textsc{k}$$\rho$$_{\omega}$, $C_{ο}$=$textsc{k}$A/d where d is the thickness of oxide film, $\omega$ is the diffusion layer thickness. $\rho$$_{ο}$ is the resistivity of oxide film at the interface of metal and the oxide, $\rho$$_{\omega}$ is the resistivity of oxide film at intrinsic region and A is the area of the film and $textsc{k}$=0.0885$\times$10$^{-12}$ $\times$dielectric constant, (in farad/cm). It was shown that dielectric loss and frequency dependence of equivalent series capacitance decrease as anodization voltage increases. This is a consequence of the fact that the thickness of diffusion layer increases a little with increasing anodization voltage whereas the total oxide thickness is proportional to the anodization voltage. The ngative deviation of measured values from tile relation, tan $\delta$$_{f}$=0.682 $\Delta$ $C_{f}$, was also discussed based on the Impedance equations given above. Here $\Delta$ $C_{f}$ is the change in capacitance between 0.1 and 1 KHZ.KHZ.Z.