지역고용 증진을 위한 독일의 지역고용서비스 정책

Matthias Schulze-Boing 한국노동연구원 2014 국제노동브리프 Vol.12 No.1

클러스터와의 작별? 동독‘실리콘 작소니’의 위기 및 대응

Matthias Kiese 한국노동연구원 2009 국제노동브리프 Vol.7 No.6

Size, Value, and Momentum in Emerging Market Stock Returns: Integrated or Segmented Pricing?

Matthias X. Hanauer,Martin Linhart 한국증권학회 2015 Asia-Pacific Journal of Financial Studies Vol.44 No.2

In this paper, we examine size, value, and momentum patterns in the stock returns of four emerging market regions—Latin America, EMEA, Asia, and BRIC. We document a strong and highly significant value effect, and a strong but less significant momentum effect. Sub- stantial value and momentum premiums are also present for big stocks and the overall pre- miums are not mainly driven by small stocks. Furthermore, the value patterns in emerging markets are more pronounced than in developed markets. In order to examine integrated global pricing across these regions, we test whether empirical asset pricing models with global factors explain the variation in average stock returns and, in particular, we assess their ability to capture the value and momentum patterns. Since the global models perform poorly for emerging markets, we examine the performance of local factor models, and find evidence in favor of the local four-factor model with local market, size, value, and momentum factors. On the basis of our results, pricing in emerging markets does not seem to be globally inte- grated.

Direct Laser Interference Patterning of Planar and Non-Planar Steels and Their Microstructural Characterization

Matthias Bieda,Cindy Schmädicke,Andreas Wetzig,Andrés Lasagni 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.1

The direct laser interference patterning method was used to fabricate periodic structures on flat and cylindrical specimens of austenitic stainless steel (X5CrNi18-10) and martensitic bearing steel (100Cr6). In such laser processing the characterization of materials is a central issue. Therefore, this paper places special emphasis on the chemical, metallurgical and mechanical characterization of the laser processed metals. During the patterning process of 100Cr6, the carbides in the martensitic structure appear as elongated needles and become aligned to the direction of melt flow. The chemical composition analysis before and after laser interference patterning did not reveal any significant changes to either material. However, the surface hardness of 100Cr6 decreased when energy densities above 2.0 J/cm2 were applied. For cylindrical specimens, the grating period changes with position along the circumference. The observed difference, however, is less than ~6.4% for rotation angles smaller than 20°.

Parameter Identification and Model Validation for the Piezoelectric Actuator in an Inertia Motor

Matthias Hunstig,Tobias Hemsel 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.41

Piezoelectric inertia motors make use of the inertia of a slider to drive the slider by friction contact in a series of small steps which are generally composed of a stick phase and a slip phase. If the best electrical drive signal for the piezoelectric actuator in an inertia motor is to be determined, its dynamical behaviour must be known. A classic dynamic lumped parameter model for piezoelectric actuators is valid only in resonance and, therefore, is not suitable for modelling the actuator in an inertia motor. A reduced dynamic model is used instead. Its parameters are identified using a step response measurement. This model is used to predict the movement of the actuator in response to a velocity-optimized signal introduced in a separate contribution. Results show that the model cannot represent the dynamical characteristics of the actuator completely. For determining voltage signals that let piezoelectric actuators follow a calculated movement pattern exactly, the model can, therefore, only be used with limitations.

Drive Signals for Maximizing the Velocity of Piezoelectric Inertia Motors

Matthias Hunstig,Tobias Hemsel 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.41

Piezoelectric inertia motors have a simple construction and are controlled by a single driving signal. This allows for miniaturization and low-cost production. One of the main questions to be answered during the design process of a piezoelectric inertia motor is which electrical excitation signal yields optimum motor characteristics. Three signals and their variants are widely used in the literature: sawtooth, parabolic and cycloidic signals. Within this paper, we propose to use a rigid body model of a simple inertia motor to predict the dependance of the motor characteristics on the movement pattern of the driving element. The advantages and the disadvantages of three different drive signals that maximize the motor velocity are discussed.

The Adjacent Vessel Sign on Breast MRI: New Data and a Subgroup Analysis for 1,084 Histologically Verified Cases

Matthias Dietzel,Pascal A.T. Baltzer,Tibor Vag,Aimee Herzog,Mieczyslaw Gajda,Oumar Camara,Werner A. Kaiser 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.2

Objective: The adjacent vessel sign (AVS) is a descriptor for differentiating malignant from benign breast lesions on breast MRI (bMRI). This investigation was designed to verify the previous reports on the diagnostic accuracy of AVS and to assess correlation between AVS, histopathological diagnosis, lesion size and lesion grade. Materials and Methods: This study was approved by the local ethical committee. Experienced radiologists evaluated 1,084 lesions. The exclusion criteria were no histological verification after bMRI and breast interventions that were done up to one year before bMRI (surgery, core biopsy, chemo- or radiation therapy). The native and dynamic contrast-enhanced T1-weighted series were acquired using standardized protocols. The AVS was rated positive if a vessel leading to a lesion could be visualized. Prevalence of an AVS was correlated with the lesions’ size, grade and histology using Chi-square-tests. Results: The AVS was significantly associated with malignancy (p < 0.001; sensitivity: 47%, specificity: 88%, positive-predictive-value [PPV]: 85%). Malignant lesions > 2 cm more often presented with an AVS than did those malignant lesions < 2 cm (p < 0.0001; sensitivity: 65%, PPV: 90%). There was no correlation of the AVS with the tumor grade. The prevalence of an AVS didn’t significantly differ between invasive lobular carcinomas versus ductal carcinomas. In situ cancers were less frequently associated with an AVS (p < 0.001). Conclusion: The adjacent vessel sign was significantly associated with malignancy. Thus, it can be used to accurately assess breast lesions on bMRI. In this study, the AVS was particularly associated with advanced and invasive carcinomas. Objective: The adjacent vessel sign (AVS) is a descriptor for differentiating malignant from benign breast lesions on breast MRI (bMRI). This investigation was designed to verify the previous reports on the diagnostic accuracy of AVS and to assess correlation between AVS, histopathological diagnosis, lesion size and lesion grade. Materials and Methods: This study was approved by the local ethical committee. Experienced radiologists evaluated 1,084 lesions. The exclusion criteria were no histological verification after bMRI and breast interventions that were done up to one year before bMRI (surgery, core biopsy, chemo- or radiation therapy). The native and dynamic contrast-enhanced T1-weighted series were acquired using standardized protocols. The AVS was rated positive if a vessel leading to a lesion could be visualized. Prevalence of an AVS was correlated with the lesions’ size, grade and histology using Chi-square-tests. Results: The AVS was significantly associated with malignancy (p < 0.001; sensitivity: 47%, specificity: 88%, positive-predictive-value [PPV]: 85%). Malignant lesions > 2 cm more often presented with an AVS than did those malignant lesions < 2 cm (p < 0.0001; sensitivity: 65%, PPV: 90%). There was no correlation of the AVS with the tumor grade. The prevalence of an AVS didn’t significantly differ between invasive lobular carcinomas versus ductal carcinomas. In situ cancers were less frequently associated with an AVS (p < 0.001). Conclusion: The adjacent vessel sign was significantly associated with malignancy. Thus, it can be used to accurately assess breast lesions on bMRI. In this study, the AVS was particularly associated with advanced and invasive carcinomas.

Assessing the Impact of Trade Liberalization: The Case of Jordan

( Matthias Busse ),( Steffen Groning ) 세종대학교 경제통합연구소 2012 Journal of Economic Integration Vol.27 No.3

This paper assesses the impact of Jordan`s substantial trade liberalization over the last two decades. Using a gravity model, a large country sample, and a long time-series, we estimate the effects of various Free Trade Agreements (FTAs) and the World Trade Organization (WTO) accession on both Jordan`s exports and imports. Overall, we find that the impact has been rather small, as no statistically significant and robust impact on exports and imports can be found due to multilateral or preferential trade liberalization. However, there is one exception: the FTA with the United States of America has boosted Jordan`s exports to the US to a considerable degree.

In vitro Stability of Heat Shock Protein 27 in Serum and Plasma Under Different Pre-analytical Conditions: Implications for Large-Scale Clinical Studies

Matthias Zimmermann,Denise Traxler,Elisabeth Simader,Christine Bekos,Benjamin Dieplinger,Mitja Lainscak,Hendrik Jan Ankersmit,Thomas Mueller 대한진단검사의학회 2016 Annals of Laboratory Medicine Vol.36 No.4

The effects of storage temperatures, repeated freeze-thaw cycles, or delays in separating plasma or serum from blood samples are largely unknown for heat shock protein 27 (HSP27). We evaluated (1) the imprecision of the HSP27 assay used in this study; (2) the in vitro stability of HSP27 in blood samples stored at 4°C for up to 6 hr with immediate and delayed serum/plasma separation from cells; and (3) the in vitro stability of HSP27 in blood samples stored at -80°C after repeated freeze-thaw cycles. The ELISA to detect HSP27 in this study showed a within-run CV of <9% and a total CV of <15%. After 4-6 hr of storage at 4°C, HSP27 concentrations remained stable when using serum tubes irrespective of sample handling, but HSP27 concentrations decreased by 25-45% when using EDTA plasma tubes. Compared with baseline HSP27, one freeze-thaw cycle had no effect on serum concentrations. However, plasma concentrations increased by 3.1-fold after one freeze-thaw cycle and by 7.3-fold after five freeze-thaw cycles. In conclusion, serum is an appropriate biological sample type for use in epidemiological and large-scale clinical studies.

2018년 독일 노동시장 및 노사관계 전망

Matthias Knuth 한국노동연구원 2018 국제노동브리프 Vol.16 No.2