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Networks of hiking tourist trails in the Krkono?e(Czech Republic) and Peneda-Gerês(Portugal) national parks-comparative analysis

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Journal of Mountain Science 2019年第4期16卷 725-743页

作者： Krzysztof ko?ODZieJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional Development University of Wroclaw

Tourist trails as a linear form of tourist infrastructure fulfill various functions(i.e. recreational, ecological, economic, social, ensuring safety). They are especially important in national parks, where in selected areas tourist penetration is allowed only along specially designed, official routes. A well-planned layout of tourist trails with appropriate facilities can help to limit the negative consequences of tourist pressure on protected natural areas. The aim of the article is a comparison of offers for active tourists in two mountain national parks(the Krkono?e National Park in the Czech Republic and the Peneda-Gerês National Park in Portugal), taking into consideration the marked hiking trails – the most frequently used type of tourist trails. As a result the level of area coverage by the networks of hiking trails was assessed, as well as their adequateness towards the needs of tourists. The descriptive analysis was based on author's personal observations. in the examination of hiking trails as part of a system, some elements of the graph theory were used, especially coefficients for topologic analysis of spatial structure. This method enables simplification of a network, comparison of various areas and making some assumptions concerning tourist infrastructure, which is a crucial factor while analyzing trails from a tourists' point of view. in both analyzed national parks the relief is quite similar, as well as their locations near national borders, what justifies the choice of the areas scrutinized in the paper. What differ them are patterns of tourism development and the current ways of undertaking active tourism. Not similarities but the two latter factors resulted in a distinct character of the two compared networks of trails and facilities connected with them. The system of hiking trails and tourist infrastructure seem better developed in the Krkono?e National Park, what can be explained by historical and social conditions, especially the adopted model

关键词： Hiking tourist trails Tourist infrastructure Mountains National parks Network Graph analysis

is prostate cancer a Lynch syndrome cancer？

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Asian Journal of Andrology 2013年第5期15卷 588-589页

作者： Aung ko Win Centre for Molecular Environmental Genetic andAnalytic Epidemiology Melbourne School of Populationand G oba Heath Parkv e Vc. 3010 Austra a

The question of whether men with an inherited genetic condition called Lynch syndrome have an increased risk of developing prostate cancer has been controversial. it is important to answer this question, for understanding the role of DNA mismatch repair in carcinogenesis of prostate as well as for clinical implications for screening.

关键词： prostate cancer Lynch syndrome cancer

Diagnosis of clinical and subclinical varicocele： how has it evolved？

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Asian Journal of Andrology 2016年第2期18卷 182-185,J0002,J0003页

作者： Ruth e Belay Gene Omar Huang Jim Ken-Chie Shen edmund Yuey Kun ko Department of Urology Loma Linda University School of Medicine Loma Linda California USA.

in this review, we examine the evolution and application of various diagnostic modalities for varicoceles starting with venography, scintigraphy, and thermography and their role in the evaluation of a varicocele patient. Some of these methods have been supplanted by less invasive and more easily performed diagnostic modalities, especially ultrasound and Doppler examination of the scrotum. Advances in ultrasound and magnetic resonance imaging hold the potential to expand the role of imaging beyond that of visual confirmation and characterization of varicoceles. The ability to identify the early indicators of testicular dysfunction based on imaging findings may have implications for the management of varicoceles in the future.

关键词： scrotum testis varicocele

Chemical effects on the sliding friction of Ag and Au(111)

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Friction 2018年第1期6卷 84-97页

作者： H.e.ko S.G.KWAN H.W.PARK A.CARON korea Tech–korea University of Technology and education

We have investigated the sliding friction behavior of metallic couples with different enthalpy of mixing or reaction by friction force microscopy. Comparing the friction behavior of miscible and immiscible couples we find that in the first case friction is governed by adhesion while the shear strength is low(τ = 3–6 MPa). in the latter case of immiscible couples, adhesion is found to be low and the shear strength is large(τ≈ 70 MPa). Statistical analysis of atomic stick-slip images recorded on an Au(111) surface with tips of different affinities with gold allows for a deeper understanding of our results. The periodicity of atomic stick-slip images corresponds to the interatomic distance of gold for immiscible counter-bodies. in contrast, for a reactive couple the periodicity of atomic stick-slip significantly differs from the gold interatomic distance and may correspond to the structural length of an ordered intermediate phase at the tip-surface interface.

关键词： metals surface friction nanotribology atomic force microscopy

Approximate solutions of Schrdinger equation for eckart potential with centrifugal term

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Chinese Physics B 2010年第9期19卷 155-160页

作者： F. Taskin G. koak Department of Physics Erciyes University

The approximate analytical solutions of the Schrodinger equation for the eckart potential are presented for the arbitrary angular momentum by using a new approximation of the centrifugal term. The energy eigenvalues and the corresponding wavefunctions are obtained for different values of screening parameter. The numerical examples are presented and the results are in good agreement with the values in the literature. Three special cases, i.e., s-wave, ξ= λ=1, and β=0, are investigated.

关键词： Schrodinger equation eckart potential bound state

Advanced prediction of organic–metal interactions through DFT study and electrochemical displacement approach

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Journal of Magnesium and Alloys 2023年第1期11卷 301-316页

作者： Abdelkarim Chaouiki Wail Al Zoubi Young Gun ko Materials electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541South Korea

Heterocyclic compounds are the promising biological compounds as nature-friendly for the corrosion protection of metallic *** this work,three heterocyclic compounds such as 1-azanaphthalene-8-ol(8-AN),2-methylquinoline-8-ol(8-MQ),and 8-quinolinol-5-sulfonic acid(8-QSA)were used as green compounds,and their anti-corrosion performance for AZ31 Mg in saline water was discussed on the basis of impedance interpretation and surface *** found that the electrochemical performance was improved in the order of 8-AN>8-MQ>8-QSA,demonstrating the electron donor effect of N-heterocycles to form coordination complexes on the magnesium *** the electrochemical performance,the protective layer constructed at the optimal concentration reinforces the barrier against aggressive environments,with potential inhibition efficiency of 87.4%,99.0%,and 99.9%for 8-QSA,8-MQ,and 8-AN,*** chemical parameters and electron density distribution for free organic species in the absence and presence of Mg^(2+)cation were evaluated using density functional theory(DFT).Upon the formation of coordination complexes between organic compound and Mg^(2+),energy gap underwent change about Δe=5.7 eV in the 8-AN/Mg^(2+)***,the adsorption of heterocyclic compounds on Mg surface reveals the formation of strong covalent bonds with Mg atoms,which further confirmed by the electron density difference and projected density of states *** on theoretical calculations,three inhibitors can adsorb on the metal surface in both parallel and perpendicular orientations via C,O and N *** the parallel configuration,the C-Mg,N-Mg and O-Mg bond distances are between 2.11 and 2.25˚A,whereas the distances in the case of perpendicular adsorption are between 2.20 and 2.40˚A(covalent bonds via O and N atoms).The results indicated that parallel configurations are energetically more stable,in which the adsorption energies are-4.48 eV(8-AN),-4.28 eV(8-MQ)and-3.82 e

关键词： Organic layer Heterocyclic compounds electrochemical behavior DFT modeling

Density functional theory study on the role of ternary alloying elements in TiFe-based hydrogen storage alloys

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Journal of Materials Science & Technology 2021年第33期92卷 148-158页

作者： Won-Seok ko Ki Beom Park Hyung-Ki Park School of Materials Science and engineering University of UlsanUlsan 44610Republic of Korea Functional Materials and Components R&D Group Korea Institute of Industrial TechnologyGangneung 25440Republic of Korea

The role of additional ternary alloying elements on the performance of stationary TiFe-based hydrogen storage alloys was investigated based on first-principles density functional theory *** a basic step for examinations,the site preference of each alloying element in the stoichiometric and nonstoichiometric B2TiFe compounds was clarified considering possible antisite *** on the revealed site preference,the effect of various possible ternary elements on the hydrogen storage was examined by focusing on the formation enthalpies of TiFeH and TiFeH_(2) hydrides,which were closely related to the change in the location of plateaus in the pressure-composition-temperature *** physical properties such as the volume expansion due to hydride formation were also examined to provide additional criteria for selecting optimum alloying conditions in future alloying design *** alloying elements that maximize the grain boundary embrittlement due to the solute segregation were proposed for the enhanced initial activation of TiFe-based hydrogen storage alloys.

关键词： Hydrogen storage alloy Titanium-iron Density functional theory calculation Metallic hydride

Analytical evaluation and experimental validation on dynamic rocking behavior for shallow foundation considering structural response

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earthquake engineering and engineering Vibration 2022年第1期21卷 37-51页

作者： Kil-Wan ko Jeong-Gon Ha Dong-Soo Kim Department of Civil and environmental engineering UC BerkeleyCalifornia 94720USA Advanced Structures and Seismic Safety Research Division Daejeon 34057Korea Department of Civil and environmental engineering KAISTDaejeon 34141Korea

The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong *** this study,the dynamic rocking behavior for a shallow foundation considering structural response was evaluated through two analytical approaches:the conventional soil-foundation-structure interaction(SFSi)governing equation of a single-degree-of-freedom(SDOF)structure on a rocking shallow foundation,and the Housner rocking model(i.e.,a rocking rigid block on a rigid base).Both approaches were validated with dynamic centrifuge *** test models consisted of a soft soil deposit,a shallow rectangular foundation,and an SDOF structure dominated by a bending behavior.A total of 11 foundation-structure systems and six seismic waves,including recorded earthquake signals and sinusoidal waves,were *** results showed that the conventional SFSi equation well predicted the maximum rotation during strong ***,this method was less accurate regarding the rotational phase information and maximum rotation of the foundation during weak *** the other hand,although the modified Housner′s rocking model required five parameters relevant to a soil-foundation-structure system,it overestimated the maximum rotation of the foundation when compared with the results from dynamic centrifuge tests.

关键词： soil-foundation-structure interaction maximum rotation angle rocking foundation Housner rocking model dynamic centrifuge test

Stick-and-play system based on interfacial adhesion control enhanced by micro/nanostructures

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Nano Research 2021年第9期14卷 3143-3158页

作者： Jung ii Yoo Seung Hyun Kim Heung Cho ko School of Materials Science and engineering Gwangju Institute of Science and Technology(GIST)Gwangju 61005Republic of Korea

The evolution of membrane-type electronics has facilitated the development of stick-and-play systems,which confer diverse electrical functions to various planar or arbitrary curvilinear *** stick-and-play concept is based on the development of thin electronic devices in a printable format and their subsequent transfer to target *** development of this technology requires control of the interfacial adhesion of the electronic prints for retrieval from a carrier and transfer to the target ***,we discuss the transfer printing for membrane-type electronics,starting from an overview of materials available for flexible substrates,transfer printing of electronic prints for retrieval,and assembly for further ***,we explain the stick-and-play concept based on fabricated membrane-type electronics;"stick" and “play"refer to the transfer of electronic devices and the performance of their electronic functions,*** particular,we broadly survey various methods based on micro/nanostructures,including ge.ko-inspired,interlocking,cephalopod-sucker-inspired,and cilia structures,which can be employed to stick-and-play systems for enhancing interfacial adhesion with complex target surfaces under dynamic and wet ***,we highlight the stick-and-play system application of micro/nanostructures for skin-attachable biomedical electronics,e-textiles,and environmental monitoring electronics.

关键词： transfer printing interfacial adhesion flexible electronics stick-and-play system bioinspired adhesive