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Journal of Mountain Science 2018年第2期15卷 280-295页

作者： CHUN Jung-Hwa lee chang-Bae Division of Forest Ecology National Institute of Forest Science Global Resources Division Korea Forestry Promotion Institute

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

关键词： Community structure Deterministicprocess Elevational gradient Neutral process Phylogenetic diversity Species richness

Implementation of tactical maneuvers with maneuver libraries

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Chinese Journal of Aeronautics 2020年第1期33卷 255-270页

作者： Do hyeon lee chang-Joo KIM Sung wook HUR Seong han lee School of Aerospace Information Engineering Konkuk UniversitySeoul 05029Republic of Korea

This study creates and combines the general maneuver libraries for fixed-wing aircraft to implement tactical ***,the generalized maneuver libraries are established by analyzing the characteristics of tactical maneuvers required in *** 7th order polynomial is applied to both the creation of the maneuver libraries and the generation of the trajectories or flight paths for modal *** track the desired trajectory,we design the Attitude Command Attitude Hold(ACAH)system and the Rate Command Rate Hold(RCRH)system using Model Following Controller(MFC).Moreover,the Line-of-Sight(LOS)guidance law is *** particular,the CONDUIT~?is employed to optimize the gains so that the control systems meet the aircraft Handling Qualities(HQ)***,flight simulations are performed for the longitudinal loop,immelmann-turn,and climb-slalom-descent maneuvers to verify that tactical aggressive maneuvers are realizable via the combination of maneuver *** study can contribute to the development of flight techniques for aircraft tactical maneuvers and to the revision of air force operational manuals.

关键词： 7th order polynomial Attitude command attitude hold system Handling qualities Maneuver libraries Rate command rate hold system Tactical maneuvers

Impact of Horizontal Resolution and Cumulus Parameterization Scheme on the Simulation of Heavy Rainfall Events over the Korean Peninsula

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Advances in Atmospheric Sciences 2011年第1期28卷 1-15页

作者： Seung-Woo lee Dong-Kyou lee Dong-Eon chang School of Earth and Environmental Sciences Seoul National University National Institute of Meteorological Research Korea Meteorological Administration

In this paper, we present the results from high-resolution numerical simulations of three heavy rainfall events over the Korean Peninsula. The numerical results show that the prediction accuracy for heavy rainfall events improved as horizontal resolution increased. The fine-grid precipitation fields were much closer to the real precipitation fields in the case of large synoptic forcing over the Korean Peninsula. In the case of large convective available potential energy and weak synoptic forcing, it seems that even when using a high resolution, the models still showed poor performance in reproducing the observed high precipitation amounts. However, activation of the cumulus parameterization scheme in the intermediate resolution of 9 km, even at a grid spacing of 3 km, had a positive impact on the simulation of the heavy rainfall event.

关键词： high resolution cumulus parameterization scheme heavy rainfall numerical simulation

Locally recurrent penile apocrine carcinoma initially diagnosed as metastatic adenocarcinoma of colon

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Chinese Journal of Cancer Research 2013年第6期25卷 777-780页

作者： Ok-Jun lee seok-Joong Yun Wun-Jae Kim Song-Yi Choi Ho-chang lee Hyung-Geun Song Sung-Nam Lim Ki-Hyeong lee Seung-Taik Kim Hye-Suk Han Department of Pathology College of MedicineChungbuk National University Department of Urology College of MedicineChungbuk National University Department of Internal Medicine College of MedicineChungbuk National University Department of Internal Medicine College of MedicineChungbuk National University

Apocrine carcinoma is a rare malignant adnexal neoplasm. The differential diagnosis between apocrine carcinoma and cutaneous metastasis is often difficult. Here, we report a case of locally recurrent penile apocrine carcinoma initially diagnosed as metastatic adenocarcinoma of the colon. A 75-year-old man with a history of surgical resection due to sigmoid colon cancer and penile metastasis two years prior to this study presented with a nodule at the left penile base. He underwent a wide local resection of the penile mass under a suggested preoperative diagnosis of extra-mammary Paget＇s disease （EMPD） associated with previous sigmoid colon cancer. However, the previously and currently resected penile masses were identified as primary apocrine carcinoma upon hematoxylin and eosin （H＆E） staining and immunohistochemical staining. Although the incidence is extremely rare, both clinicians and pathologists should be alert to the possibility of synchronous double primary apocrine carcinoma in cancer patients with malignant cutaneous lesions.

关键词： Apocrine glands carcinoma colon cancer penis

Optimal design considering structural efficiency of compressed natural gas fuel storage vessels for automobiles

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 199-204页

作者： Myung-chang KANG Hyung Woo lee Chul KIM National Core Research Center for Hybrid Materials Solution Pusan National University Research Institute of Mechanical Technology Pusan National University

The shape and thickness of the dome were investigated with the aim of optimizing the type II CNG storage vessels by using a finite element analysis technique. The thickness of the liners and reinforcing materials was optimized based on the requirement of the cylinder and dome parts. In addition, the shape of the dome, which is most suitable for type lI CNG storage vessels, was proposed by a process of review and analysis of various existing shapes, and the minimum thickness was established in this sequence： metal liners, composite materials and dome parts. Therefore, the new proposed shape products give a mass reduction of 4.8 kg（5.1%）

关键词： CNG fuel storage vessel mechanical property dome part bursting structural analysis

Performance Investigation of Capillary Tubes for Machine Tool Coolers Retrofitted with HFC-407C Refrigerant

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 933-939页

作者： WANG Fujen chang Tongbou CHIANG Weiming lee Haochung Department of Refrigeration and Air Conditioning Engineering Chin-Yi University of Technology Department of Mechanical Engineering Southern Taiwan University Energy & Environment Research Laboratories Industrial Technology Research Institute

The machine tool coolers are the best managers of coolant temperature in avoiding the deviation of spindle centerline for machine tools. However, the machine coolers are facing the compressed schedule to phase out the HCFC （hydro-chloro-floro-carbon） refrigerant and little attention has been paid to comparative study on sizing capillary tube for retrofitted HFC （hydro-floro-carbon） refrigerant. In this paper, the adiabatic flow in capillary tube is analyzed and modeled for retrofitting of HFC-407C refrigerant in a machine tool cooler system. A computer code including determining the length of sub-cooled flow region and the two phase region of capillary tube is developed. Comparative study of HCFC-22 and HFC-407C in a capillary tube is derived and conducted to simplify the traditional trial-and-error method of predicting the length of capillary tubes. Besides, experimental investigation is carried out by field tests to verify the simulation model and cooling performance of the machine tool cooler system. The results from the experiments reveal that the numerical model provides an effective approach to determine the performance data of capillary tube specific for retrofitting a HFC-407C machine tool cooler. The developed machine tool cooler system is not only directly compatible with new HFC-407C refrigerant, but can also perform a cost-effective temperature control specific for industrial machines.

关键词： machine tool cooler capillary tube refrigerant retrofitting

Experimental Investigation of Capacity Control Scheme on System Performance for a Machine Tool Cooler

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 333-339页

作者： WANG Fujen chang Tongbou KAO Jianwei lee Haochung Department of Refrigeration Air Conditioning and Energy Engineering Chin-Yi University of Technology Taiehung 411 Taiwan China Department of Mechanical Engineering Southern Taiwan University Tainan 710 Taiwan China Energy and Environment Research Laboratories Industrial Technology Research Institute Hsinchu 310 Taiwan China

Highly accurate manufacture in machining industry can only be obtained with precise temperature control of the coolant （oil or water）.Machine tool with more accurate,stable and advanced the precision of the working component cannot be developed without appropriate ***,the machine tool coolers are facing the control hunting of cooling temperature and the dramatic variation of heat load in high-accuracy *** main objective of this study is to evaluate the influence of the hot-gas by-pass scheme and suction regulation for capacity control of a machine tool cooler *** this study,experimental investigation on both hot-gas by-pass scheme and suction valve regulation for capacity control has been *** of using capillary tube and thermostatic expansion valve along with different capacity control scheme have been investigated extensively in an environmental testing *** performance and power consumption of the cooler system have been measured and analyzed as well by comparing with different opening percentage of throttling valve under specific coolant *** experimental results reveal that the power consumption will reduce slightly by capacity control using the hot-gas by-pass scheme but the coefficient of performance （COP） of the overall system will *** coolant temperature will result in higher compressor power consumption as *** conducting suction valve regulating for capacity control,energy-saving at 10%-12% can be obtained by using thermostatic expansion valve under different evaporator *** also reveals that suction valve regulation along with adequate choice of thermostatic expansion valve can provide alternative choice for steady capacity control and substantial *** proposed cooler systems with different capacity control schemes are not only more cost-effective than inverter driven system,but also can perform energy-saving and precise temperature control specific for high-accur

关键词： machine tool cooler hot-gas by-pas suction regulation capacity control

Structural stability estimation of whirling unit

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中国有色金属学会会刊：英文版 2009年第B9期19卷 202-208页

作者： Son-Jae HWAN Han-chang WOO lee-Sang RYONG lee-Young MOON Daegu Machinery Institute of Component & Materials Foundation Department of Automobile Yeungnam College of Science & Technology Department of Mechanical Engineering Kyung pook National University

Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by using ADAMS and NASTRAN softwares. Each maximum force acting on the bearing attached to the spindle assembly and the cutting tool attached to the whirling ring with the rotating speed of 6 000 r/min was 235 N and 902 N respectively. The maximum stress of 0.74 MPa on the base frame is far smaller than the yield strength of 282 MPa. The calculated natural frequency of 148 Hz of the system is far from the frequency of the driving speed of 6 000 r/min. The experimentally obtained maximum cutting force of 792 N is smaller than that of calculated value. And the experimentally obtained natural frequency of 118 Hz is beyond the driving speed of 6000 r/min. From above results it can be judged that the whirling system is statically and dynamically stable.

关键词：旋转工件稳定性评价 NASTRAN软件动态稳定性结构单元固有频率行车速度

Microstructure of fast tool servo machining on copper alloy

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中国有色金属学会会刊：英文版 2012年第S3期22卷 820-824页

作者： Hong LU Soo-chang CHOI Sang-min lee Deug-woo lee Department of Nano Fusion Technology Pusan National University Korea Institute of Machinery & Materials Department of Nano Mechatronics Engineering Pusan National University

The development of the fast tool servo (FTS) for precision machining was *** micron machining performance of a piezoelectric-assisted FTS on copper alloy was *** results indicate that the quality of the microstructure depends mainly on two important factors:the cutting speed (or spindle speed) and the driving frequency of the *** excessive driving frequency increases the formation of *** effect of the clearance angle of the diamond tool on the microstructure machining precision was also investigated.

关键词： fast tool servo microstructure piezoelectric diamond machining copper alloy

Detection of thinned corticospinal tract and corticoreticular pathway in a patient with a calf circumference discrepancy

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Neural Regeneration Research 2018年第2期13卷 366-368页

作者： han do lee min cheol chang department of physical medicine and rehabilitation college of medicineyeungnam university

In clinical practice, it is challenging to elucidate the location of the lesion in a patient＇s nervous system that is causing the neurologic symptoms, because lesions are often microscopic and cannot be revealed by c... 详细信息

关键词： Detection of thinned corticospinal tract and corticoreticular pathway in a patient with a calf circumference discrepancy CRP CST