잉여 없는 웹 서비스 조합을 위한 2단계 탐색 알고리즘

김현지(Hyeonji Kim),권준호(Joonho Kwon),이대욱(Daewook Lee),이석호(Sukho Lee) 한국정보과학회 2009 정보과학회논문지 : 데이타베이스 Vol.36 No.2

최근 웹 서비스 관련 기술들이 많은 관심을 받고 있다. 그 중 하나인 웹 서비스 컴포지션에 대한 연구도 활발히 진행되고 있다. 웹 서비스 컴포지션은 기존에 존재하던 웹 서비스들을 조합하여 마치 하나의 서비스처럼 보여 주는 것이다. 웹 서비스 컴포지션을 사용하면 기존에 존재하지 않던 웹 서비스의 기능도 제공할 수 있으며 사용자에게 더 많은 질의 결과를 줄 수도 있다. 기존의 많은 웹 서비스 컴포지션 관련 연구들은 전향 혹은 후향 체인 방식을 사용하였다. 그러나 전향 체인 방식이나 후향 체인 방식은 질의와 상관없는 방향을 탐색하는 경우가 많기 때문에 많은 시간이 걸린다는 단점이 있다. 전향과 후향을 모두 사용하여 2단계로 컴포지션을 찾는 방식도 있으나, 이 방식은 컴포지션에 포함되지 않아도 되는 웹 서비스를 포함한 결과를 낸다는 문제점이 있다. 본 논문에서는 전향 단계와 후향 단계를 거쳐 웹 서비스 컴포지션을 찾는 2단계 웹 서비스 컴포지션 탐색 방법을 제안하였다. 전향 단계에서는 미리 구축한 연결 인덱스를 사용하여 좀 더 빠르게 후보 컴포지션을 찾는다. 후향 단계에서는 토큰을 사용하여 후보 컴포지션을 잉여 웹 서비스가 포함되지 않은 컴포지션으로 분해한다. 실험을 통해 2단계 웹 서비스 컴포지션이 기존의 한 방향으로 진행하는 방식보다 더 효율적이라는 것을 보였다. 또한 기존의 2단계 방식보다 더 많은 컴포지션 결과를 사용자에게 돌려주면서도 실행 시간 면에서 기존의 2단계 방식에 필적한다는 것을 보였다. In recent years, the web services composition search has become an issue of great interest. The web services composition search is the process of integrating individual web services to yield desired behavior. Through the web services composition search, more sophisticated functionalities can be provided. Current solutions can be classified into three main classes: forward chaining approach, backward chaining approach and two-phase approach. However one-way chaining approaches, such as forward chaining approach and backward chaining approach have limitations of searching irrelevant web services. And two-phase approach has limitations of including redundant web services. In this paper, we propose an unredundant web services composition search based on the two-phase algorithm. The algorithm consists of a forward phase and a backward phase. In the forward phase, the candidate web services participating composition will be found efficiently by searching the Link Index. In the backward phase, unredundant web services compositions will be generated from candidate web services by using the Token Manager. The experimental results show that our proposed algorithm is more efficient than one-way chaining approaches. The experimental results also show that our algorithm can provide more solutions than previous two-phase approach and is comparable to previous one in execution time.

Effects of Contrast Phases on Automated Measurements of Muscle Quantity and Quality Using CT

Kim Dong Wook,Kim Kyung Won,Ko Yousun,Park Taeyong,Lee Jeongjin,Lee Jung Bok,Ha Jiyeon,Ahn Hyemin,Sung Yu Sub,Kim Hong-Kyu 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.11

Objective: Muscle quantity and quality can be measured with an automated system on CT. However, the effects of contrast phases on the muscle measurements have not been established, which we aimed to investigate in this study. Materials and Methods: Muscle quantity was measured according to the skeletal muscle area (SMA) measured by a convolutional neural network-based automated system at the L3 level in 89 subjects undergoing multiphasic abdominal CT comprising unenhanced phase, arterial phase, portal venous phase (PVP), or delayed phase imaging. Muscle quality was analyzed using the mean muscle density and the muscle quality map, which comprises normal and low-attenuation muscle areas (NAMA and LAMA, respectively) based on the muscle attenuation threshold. The SMA, mean muscle density, NAMA, and LAMA were compared between PVP and other phases using paired t tests. Bland-Altman analysis was used to evaluate the inter-phase variability between PVP and other phases. Based on the cutoffs for low muscle quantity and quality, the counts of individuals who scored lower than the cutoff values were compared between PVP and other phases. Results: All indices showed significant differences between PVP and other phases (p < 0.001 for all). The SMA, mean muscle density, and NAMA increased during the later phases, whereas LAMA decreased during the later phases. Bland-Altman analysis showed that the mean differences between PVP and other phases ranged -2.1 to 0.3 cm2 for SMA, -12.0 to 2.6 cm2 for NAMA, and -2.2 to 9.9 cm2 for LAMA.The number of patients who were categorized as low muscle quantity did not significant differ between PVP and other phases (p ≥ 0.5), whereas the number of patients with low muscle quality significantly differed (p ≤ 0.002). Conclusion: SMA was less affected by the contrast phases. However, the muscle quality measurements changed with the contrast phases to greater extents and would require a standardization of the contrast phase for reliable measurement.

Synthesize of V4AlC3 Based MAX Phase Composites by Reactive Spark Plasma Sintering of V2O5:Al:C

Leila Sadeghi,Mansour Razavi,Mohammad Mahdi Kalantarian,Mohammad Reza Rahimipour,Mohsen Hossein‑Zadeh 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

In this research V4AlC3based composites were synthesized by reactive spark plasma sintering (RSPS) method. V2O5:Al:Cstarting materials with molar ratios of 1:6:1.5 and 1:7:1.5 were heat treated at 1400 °C. Final composition, microstructural,physical, mechanical and tribological properties of the prepared composites were compared. The X-ray diffraction analysisresults showed that the formation of V4AlC3as main phase alongside Al2O3and V2AlCby-products. Increasing the Al contentfrom 6 moles to 7 moles led to formation of VC0.845and Al2O3main phases as well as V4AlC3and V2AlCminor phases in thissample due to extraction of Al from die during RSPS operation. Microstructural studies revealed that the uniform distributionof the phases with low amount of porosities. The layered microstructure of the composites confirmed the formation ofMAX phases. Higher bending strength and is achieved for the synthesized composite prepared by 7 moles Al (490 ± 5 MPa)than the composite prepared with 6 moles Al (375 ± 11 MPa). The composite prepared with 7 moles Al also exhibited lowerwear rate (3.7 × 10− 5 mm3/Nm) than that of prepared with 6 moles Al (2.4 × 10− 4 mm3/Nm). Microstructural studies of theworn surfaces indicated that tribo oxidation is dominant mechanism for both fabricated composites.

TEM study of microstructural development during heating in a nanolaminated amorphous ZrAlCuFe/crystalline CuCoFeNi composite structure

Romankov, S.,Park, Y.C. Elsevier 2015 JOURNAL OF ALLOYS AND COMPOUNDS Vol.619 No.-

<P><B>Abstract</B></P> <P>A nanolaminated amorphous/crystalline composite structure with a mean lamellar thickness of around 10nm was fabricated on a Cu plate. The crystalline phase was a multicomponent non-equilibrium face-centered cubic (fcc) Cu(CoFeNi) solid solution, and the amorphous phase was a Zr-based compound containing Al, Cu, and Fe. The composite’s thermal stability and microstructural transformation was studied over the temperature range of 200–900°C. The lamellae maintained their shape during heating up to 600°C. Transformation of the structure began with separation of the elements inside the crystalline lamellae. In early stages of the transformation, hardening occurred. At 600°C, an interconnected CoFe phase started to appear with an ordered body-centered cubic (bcc) crystal structure. When the temperature was increased further, the nanolaminated structure degraded and the bcc CoFe phase grew. At 750°C, the bcc CoFe phase formed a complex network that surrounded the formerly amorphous regions, and the bcc CoFe phase started transforming to the fcc configuration. The Cu atoms segregated to the grain boundaries of the fcc CoFe(Ni) phase. The amorphous phase gradually crystallized into nanometer-sized polycrystalline grains that were attributed to the Zr(Al)O<SUB>2</SUB> phase. As a result of these transformations, heating at 900°C produced a morphologically complex nanocomposite structure consisting of branched grains of Zr(Al)O<SUB>2</SUB> and fcc CoFe(Ni) with Cu inclusions. When the nanolaminated structure had completely transformed, the layer was softer than it had been in the initial annealing steps, but was still almost five times as hard as the initial Cu plate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microstructural transformation in amorphous/crystalline structure was studied. </LI> <LI> Amorphous/crystalline structure was stable during heating up to 600°C. </LI> <LI> Transformation of the amorphous/crystalline structure occurred at temperatures above 600°C. </LI> <LI> Heating of the non-equilibrium multicomponent system produced complex patterns. </LI> <LI> Heating at 900°C produced a new morphologically complex nanocomposite structure. </LI> </UL> </P>

Electrical Characteristics of Poly(ethylene oxide)-urea Complex Films

Cho, Mi-Yeon,Cho, Kyoung-Ah,Kim, Sang-Sig The Korean Institute of Electrical and Electronic 2012 Transactions on Electrical and Electronic Material Vol.13 No.3

The electrical characteristics of complex films composed of poly(ethylene oxide) (PEO) and urea as a function of the urea concentration were examined in this study. Moreover, their structural characteristics were also compared. Depending on the urea concentration, the structural phases were classified as PEO+${\beta}$-phase composite, ${\beta}$-phase+${\alpha}$-phase composites, or ${\alpha}$-phase composite+urea. At urea concentrations below ~0.064 M, the ${\beta}$-phase was dominant in the complex film. Moreover, the conductance increased rapidly with an increase in the urea concentration. For urea concentrations ranging from ~0.064 to ~0.25 M, the ${\beta}$-phase was gradually substituted by the ${\alpha}$-phase. As the film was composed entirely of the ${\alpha}$-phase at urea concentrations greater than ~0.25 M, its conductance was decreased. In this study, the electrical characteristics observed for the different phases are analyzed and discussed.

Effects of alumina precursor species in a ternary-phase binder system on the strength of sand mold

Jung, Yeon-Gil,Tumenbayar, Erdenechuluun,Choi, Hyeun-Hee,Park, Hye-Young,Kim, Eun-Hee,Zhang, Jing Elsevier 2018 CERAMICS INTERNATIONAL Vol.44 No.2

<P><B>Abstract</B></P> <P>A new ternary-phase binder system incorporating alumina (Al<SUB>2</SUB>O<SUB>3</SUB>) precursors was successfully developed through process control to improve the sand mold's strength for casting of large objects. Three types of Al<SUB>2</SUB>O<SUB>3</SUB> precursors with different molecular structures, such as Al(OH)<SUB>3</SUB>, Al(OEt)<SUB>3</SUB>, and Al(NO<SUB>3</SUB>)<SUB>3</SUB> were employed in the ternary-phase binder system. A dual-dipping process was developed. The first dipping includes the ternary-phase binder composition and heat treatment at 1000 or 1200°C. The second dipping uses a binary-phase binder composed of TEOS and NaOMe and heat treatment at 1000°C. The results show that sodium aluminosilicate was synthesized in the ternary-phase binder at both temperatures, and amorphous silica was formed only in the ternary composition of TEOS/NaOMe/Al(OEt)<SUB>3</SUB>. In contrast, sodium silicate was formed in the binary-phase binder. The strength of the mold prepared with precursor Al(OEt)<SUB>3</SUB> was higher than those with Al(OH)<SUB>3</SUB> and Al(NO<SUB>3</SUB>)<SUB>3</SUB>, due to its improved glassification efficiency of Al(OEt)<SUB>3</SUB>. Additionally, the mold strength was increased with increasing content of TEOS in the ternary-phase binder composition. Finally, the optimal highest strength was obtained with the ternary-phase binder composition of TEOS/NaOMe/Al(OEt)<SUB>3</SUB> in the mole ratio of 5:1:1<I>.</I> </P>

pyMPEALab Toolkit for Accelerating Phase Design in Multi-principal Element Alloys

Upadesh Subedi,Anil Kunwar,Yuri Amorim Coutinho,Khem Gyanwali 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.1

Multi-principal element alloys (MPEAs) occur at or nearby the centre of the multicomponent phase space, and they have theunique potential to be tailored with a blend of several desirable properties for the development of materials of future. The lackof universal phase diagrams for MPEAs has been a major challenge in the accelerated design of products with these materials. This study aims to solve this issue by employing data-driven approaches in phase prediction. A MPEA is frst representedby numerical fngerprints (composition, atomic size diference , electronegativity , enthalpy of mixing , entropy of mixing, dimensionless Ω parameter, valence electron concentration and phase types ), and an artifcial neural network (ANN) isdeveloped upon the datasets of these numerical descriptors. A pyMPEALab GUI interface is developed on the top of thisANN model with a computational capability to associate composition features with remaining other input features. With theGUI interface, an user can predict the phase(s) of a MPEA by entering solely the information of composition. It is furtherexplored on how the knowledge of phase(s) prediction in composition-varied AlxCrCoFeMnNi and CoCrNiNbx can help inunderstanding the mechanical behavior of these MPEAs.

Electrical Characteristics of Poly(ethylene oxide)-urea Complex Films

조미연,김상식,조경아 한국전기전자재료학회 2012 Transactions on Electrical and Electronic Material Vol.13 No.3

The electrical characteristics of complex films composed of poly(ethylene oxide) (PEO) and urea as a function of the urea concentration were examined in this study. Moreover, their structural characteristics were also compared. Depending on the urea concentration, the structural phases were classified as PEO+β-phase composite, β-phase+α-phase composites, or α-phase composite+urea. At urea concentrations below ~0.064 M, the β-phase was dominant in the complex film. Moreover, the conductance increased rapidly with an increase in the urea concentration. For urea concentrations ranging from ~0.064 to ~0.25 M, the β-phase was gradually substituted by the α-phase. As the film was composed entirely of the α-phase at urea concentrations greater than ~0.25 M, its conductance was decreased. In this study, the electrical characteristics observed for the different phases are analyzed and discussed.

남녀 아동의 성장기별 생체전기임피던스벡터와 위상각 분포

김혜진(Hyeoi Jin Kim),김철현(Chul Hyun Kim),정소정(So Chung Chung) 한국체육측정평가학회 2012 한국체육측정평가학회지 Vol.14 No.1

이 연구는 소아청소년에서 성별과 연령에 따른 위상각과 생체전기임피던스벡터의 수준과 위치를 구하고자 하였다. 또한 연구결과를 바탕으로 위상각과 생체전기임피던스벡터가 소아청소년의 성장수준과 성별에 따른 신체구성 및 체형의 변화에 대한 정보를 제공하고자 하였다. 연구의 목적을 위해 만 6세에서 14세의 건강한 소아청소년 1,270명을 동원하여 신체계측과 생체전기저항법을 측정하여 인체저항과 리액턴스를 측정하였으며, 임피던스 및 위상각과 그래프 상에 임피던스벡터의 분포를 분석하였다. 연구결과 BMI분포 중 67백분위 이상에 대한 임피던스벡터는 유의하게 최좌측 좌표에 분포하였고, BMI 33백분위수 이하는 임피던스벡터의 포물선이 최우측 좌표에 위치하였다. 이와 동시에 위상각은 BMI의 증가와 함께 유의하게 증가했다. 성장기에 따른 여아와 남아의 임피던스 벡터와 위상각은 6~8세에서는 남·여 간의 유사하게 나타났고, 9~11세에서 여아가 남아보다 좌측에 위치하였으며, 12~14세에서 여아의 임피던스벡터는 남아보다 좌측 좌표에 위치하였다. 이때, 위상각은 6~8세에서 남아가 유의하게 높은 수준을 가졌고 연령이 증가한 9~11세에서 보다 증가하였으며, 12~14세에서 여아와 남아 간의 수준은 유사한 수준으로 회귀하였다. 이상의 결과에서 BIVA와 위상각은 성장에 의한 체형과 체세포의 증가를 구분하여 소아청소년의 신체구성을 평가 할 수 있었다. Bioelectrical impedance analysis (BIA) gives resistance (R) and reactance (Xc). R and Xc normalized by body height (H) can be plotted as a bivariate vector (R/H versus Xc/H). R and Xc can also give phase angle. Vector BIA and phase angle is useful for studying the determinants of body composition. We investigated the effect of age or growth of children on BIA results including R, Xc, Z, and phase angle and its relevance to body-composition analysis in a large database of impedance vector distribution stratified by age, sex, and body mass index (BMI) for identifying the possibility to use BIVA and phase angle for children`s growth curve. We recruited 1,279 children aged 6 to 14. First, these children were divided by three groups according to BMI tertile value. Impedance vectors and phase angle were analyzed based on three BMI groups. These children were also divided into three age groups (6-8year group, 9-11year goup, 12-14year group). Impedance vectors and phase angle were analyzed based on three age groups by sex. As results, the impedance vector distribution pattern was influenced by sex, BMI, and age, with shoter vectors in males than females (p<0.001) and shorter vectors with increasing BMI (p<0.001). Phase angle gradually increased with increasing BMI (p<0.001). However, phase angle were larger in men than in women until 11 years old. Phase angle in female aged 12 to 14 years become similar to that in male aged 12 to 14 year. These results suggest that impedance parametes, BIVA, and phase angle can predict children`s growth and body composition. We could recommend that BIVA pattern can be developed for growth curve of children and adolescent.

Effects of internal stresses and intermediate phases on the coarsening of coherent precipitates: A phase-field study

M. Asle Zaeem,H. El Kadiri,M.F. Horstemeyer,M. Khafizov,Z. Utegulov 한국물리학회 2012 Current Applied Physics Vol.12 No.2

Phase stability, topology and size evolution of precipitates are important factors in determining the mechanical properties of crystalline materials. In this article, the CahneHilliard type of phase-field model was coupled to elasticity equations within a mixed-order Galerkin finite element framework to study the coarsening morphology of coherent precipitates. The effects of capillarity, particle size and fraction,compositional strain, and inhomogeneous elasticity on the kinetics and kinematics of coherent precipitates in a binary dual phase crystal admitting a third intermediate stable/meta-stable phase were investigated. The results demonstrated the ability of the model to simulate coarsening under the concomitant action of Ostwald ripening and mismatch elastic strain mechanisms. Using a phenomenological coarsening power law, coarsening rates were determined to depend on precipitate size and volume fraction, compositional strain, and strain mismatch between precipitates and the matrix. Results also showed that the necking incubation time between two neighboring precipitates depends inversely on the precipitate’s initial sizes; however, under fixed volume fraction of precipitates, any increase in the initial sizes of the precipitates mitigates the coarsening. Meanwhile, the compositional strain and the growth of the intermediate stable/meta-stable phase leads to substantial enhancements of precipitate coarsening.