An Olethreutine Species, Bactra festa Diakonoff (Lepidoptera, Tortricidae) New to China

변봉규,Chengde Li,Huilin Han 한국응용곤충학회 2006 Journal of Asia-Pacific Entomology Vol.9 No.3

This study reports B. festa Diakonoff for the first time from China. Adults and male genital characteristics are redescribed and illustrated. All available information for host plants and distributional ranges are given.

FABRICATION OPTIMIZATION OF NANOHYDROXYAPATITE ARTIFICIAL BONE SCAFFOLDS

CIJUN SHUAI,CHENGDE GAO,YI NIE,PENGJIAN LI,JINGYU ZHUANG,SHUPING PENG,HUANLONG HU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.3

Serious microcracks often occur on the surface of nanohydroxyapatite (n-HAP) artificial bone scaffolds prepared by selectivelaser sintering(SLS) technology. In this study, we found that appropriate preheating before sintering can reduce and attenuate the cracks. The experiments showed that the cracks gradually reduced and then disappeared when the preheating temperature increased from 0 to 600°C while other parameters remain unchanged. The n-HAP particles gradually fused and grew up, while the grain size of sintered n-HAP will be attenuated with the increase of preheating temperature. This provided experimental optimal condition for the preparation of artificial bone scaffolds with nanohydroxyapatite ceramics.

An Olethreutine Species, Bactra festa Diakonoff (Lepidoptera, Tortricidae) New to China

Byun, Bong-Kyu,Li, Chengde,Han, Huilin Korean Society of Applied Entomology 2006 Journal of Asia-Pacific Entomology Vol.9 No.3

This study reports B. festa Diakonoff for the first time from China. Adults and male genital characteristics are redescribed and illustrated. All available information for host plants and distributional ranges are given.

Near-Five-Vector SVPWM Algorithm for Five-Phase Six-Leg Inverters under Unbalanced Load Conditions

Zheng, Ping,Wang, Pengfei,Sui, Yi,Tong, Chengde,Wu, Fan,Li, Tiecai The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.1

Multiphase machines are characterized by high power density, enhanced fault-tolerant capacity, and low torque pulsation. For a voltage source inverter supplied multiphase machine, the probability of load imbalances becomes greater and unwanted low-order stator voltage harmonics occur. This paper deals with the PWM control of multiphase inverters under unbalanced load conditions and it proposes a novel near-five-vector SVPWM algorithm based on the five-phase six-leg inverter. The proposed algorithm can output symmetrical phase voltages under unbalanced load conditions, which is not possible for the conventional SVPWM algorithms based on the five-phase five-leg inverters. The cause of extra harmonics in the phase voltages is analyzed, and an xy coordinate system orthogonal to the ${\alpha}{\beta}z$ coordinate system is introduced to eliminate low-order harmonics in the output phase voltages. Moreover, the digital implementation of the near-five-vector SVPWM algorithm is discussed, and the optimal approach with reduced complexity and low execution time is elaborated. A comparison of the proposed algorithm and other existing PWM algorithms is provided, and the pros and cons of the proposed algorithm are concluded. Simulation and experimental results are also given. It is shown that the proposed algorithm works well under unbalanced load conditions. However, its maximum modulation index is reduced by 5.15% in the linear modulation region, and its algorithm complexity and memory requirement increase. The basic principle in this paper can be easily extended to other inverters with different phase numbers.

Four newly recorded species of the genus Epinotia Hübner (Lepidoptera: Tortricidae) from Northeast China

변봉규,Shanchun Yan,Bong-Woo Lee,Chengde Li 한국응용곤충학회 2008 Journal of Asia-Pacific Entomology Vol.11 No.4

In this study, we report a newly recorded species, Epinotia demarniana (Fischer von Röslerstamm) from China, along with three previously unrecorded species, Epinotia bicolor (Walsingham), E. pinicola Kuznetsov, and E. ulmicola Kuznetsov, from Northeast China. Photographs of the adults and genitalia are presented.

Near-Five-Vector SVPWM Algorithm for Five-Phase Six-Leg Inverters under Unbalanced Load Conditions

Ping Zheng,Pengfei Wang,Yi Sui,Chengde Tong,Fan Wu,Tiecai Li 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.1

Multiphase machines are characterized by high power density, enhanced fault-tolerant capacity, and low torque pulsation. For a voltage source inverter supplied multiphase machine, the probability of load imbalances becomes greater and unwanted low-order stator voltage harmonics occur. This paper deals with the PWM control of multiphase inverters under unbalanced load conditions and it proposes a novel near-five-vector SVPWM algorithm based on the five-phase six-leg inverter. The proposed algorithm can output symmetrical phase voltages under unbalanced load conditions, which is not possible for the conventional SVPWM algorithms based on the five-phase five-leg inverters. The cause of extra harmonics in the phase voltages is analyzed, and an xy coordinate system orthogonal to the ab z coordinate system is introduced to eliminate low-order harmonics in the output phase voltages. Moreover, the digital implementation of the near-five-vector SVPWM algorithm is discussed, and the optimal approach with reduced complexity and low execution time is elaborated. A comparison of the proposed algorithm and other existing PWM algorithms is provided, and the pros and cons of the proposed algorithm are concluded. Simulation and experimental results are also given. It is shown that the proposed algorithm works well under unbalanced load conditions. However, its maximum modulation index is reduced by 5.15% in the linear modulation region, and its algorithm complexity and memory requirement increase. The basic principle in this paper can be easily extended to other inverters with different phase numbers.

Six New Faunistic Data of the Tribe Eucosmini from Northeast China (Lepidoptera, Tortricidae)

Byun, Bong-Kyu,Yan, Shanchun,Li, Chengde Korean Society of Applied Entomology 2006 한국응용곤충학회지 Vol.45 No.2

중국 동북지역에서 채집된 잎말이나방과의 꽃애기잎말이나방족을 대상으로 분류동정 한 결과, Semnostola megnifisa (Kuznetsov)가 중국에서는 처음으로 보고 된다. 이 외에 중국 동북지역에서 처음으로 분포가 확인되는 4종(Ancylis badiana (Denis et Schifferm$\"{u}$ller), Blastethia turionella (Linnaeus), Eucosma aemulana (Schl$\"{a}$ger), Sillybiphora devia Kuznetsov) 및 흑룡강성미기록종인 Rhopalovalva grapholitana (Caradja)에 대하여 간략한 외부형태적 특징과 분포, 기주식물정보를 정리하였으며, 성충 및 암수생식기의 특징을 도해하였다. We report a species of the tribe Eucosmini belonging to the family Tortricidae for the first time from China: Semnostola magnifisa (Kuznetsov) and add four species for the Northeast Chinese fauna: Ancylis badiana (Denis et Schifferm$\"{u}$ller), Blastethia turionella (Linnaeus), Eucosma aemulana (Schl$\"{a}$ger), and Sillybiphora devia Kuznetsov. Also Rhopalovalva grapholitana (Caradja) is recorded for the first time from the Province Heilongjiang. Adults and genital characteristics for species are redescribed and illustrated. All available information for their host plants and distributional ranges are given.

Effect of Sc Content on the Microstructure and Properties of Al–Mg–Sc Alloys Deposited by Wire Arc Additive Manufacturing

Lingling Ren,Huimin Gu,Wei Wang,Shuai Wang,Chengde Li,Zhenbiao Wang,Yuchun Zhai,Peihua Ma 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.1

Despite showing considerable potential, wire arc additive manufacturing (WAAM) has been limited to producing Al–Mgalloys. As the addition of Sc can improve the mechanical properties of Al–Mg alloys, in this study, Al–Mg–Sc alloy depositswith different Sc contents were prepared by a WAAM process. The porosity, microstructure, and mechanical properties ofthe deposits were studied. At Sc contents less than 0.15%, Sc was completely dissolved in the Al matrix without grain refinement,and the mechanical properties were slightly improved. At a Sc content of 0.3%, the primary Al3Scphase precipitatedout of the as-deposited body, resulting in an abrupt change in the microstructure, significant grain refinement, significantlyincreased tensile strength and yield strength, with a tensile strength, yield strength, and elongation of 372 MPa, 270 MPa,and 22.5%, respectively. Following heat treatment at 350 °C for 1 h, the grain boundaries were refined and the secondaryAl3Scphase was precipitated. Furthermore, the tensile strength and yield strength were significantly increased to 415 MPaand 279 MPa, respectively, and elongation decreased to 18.5%. At a Sc content of 0.45%, due to the aggregated precipitatedphase, the coarsened grain boundaries and the limited solid solution amount of Sc in the α(Al) matrix (~ 0.25%), themechanical properties were not further improved compared with the deposit with Sc content of 0.3%. Thus, based on economicconsiderations, the optimal Sc content was 0.3%. Owing to their enhanced mechanical properties, WAAM-producedAl–Mg–Sc alloys are expected to have a wide range of applications in aviation, aerospace.