Selection Attributes of Theme Parks in China : An Exploratory Factor Analysis Approach

Lu Jun,Sul Hoonku 동북아시아문화학회 2012 동북아 문화연구 Vol.1 No.32

환대 기업 관련 선택 속성 연구는 많이 되어 왔지만, 중국 테마 공원의 선택 속성은 거의 연구된 적이 없었다. 기존에 연구된 선택 속성 항목과 전문가 집단연구를 통해 초기 항목을 설정하여 중국의 대표적인 테마 공원의 방문객을 대상으로 설문 조사를 실시하여 중국의 테마 공원의 선택 속성 측정 도구를 개발하였다. 두 개의 중국 테마 공원을 북경 근교의 Fragrant Hills Park와 상해 근교의 Happy Valley 공원을 방문한 방문객들의 기대를 중심으로 선택 속성을 측정하였다. 본 연구는 중국의 테마 공원을 방문하는 고객들이 기대하는 선택 기준을 중요도 측면에서 느낀정도를 미리 준비해 놓은 설문 항목 별로 표시하도록 하였다. 본 테마 공원에 방문하는 고객들은 방문 선택 속성으로 14개의 항목이 가장 대표성이 있는 항목으로 인식하고 있었으며 대표적 요인으로 주제, 접근성, 지원시설, 방문 가치로 요약 할 수 있었다. 현재 중국의 경제적 성장으로 인한 중국의 테마 공원에 대한 관심이 고조되는 상황에서 현실적으로 적용이 가능하고 업계의 전략을 수립하는데 매우 유용한 측정 도구가 될 것이다.

Aprotic and Aqueous Li–O₂ Batteries

Lu, Jun,Li, Li,Park, Jin-Bum,Sun, Yang-Kook,Wu, Feng,Amine, Khalil American Chemical Society 2014 Chemical reviews Vol.114 No.11

<P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/chreay/2014/chreay.2014.114.issue-11/cr400573b/production/images/medium/cr-2013-00573b_0033.gif'></P>

Magnetism in lithium-oxygen discharge product.

Lu, Jun,Jung, Hun-Ji,Lau, Kah Chun,Zhang, Zhengcheng,Schlueter, John A,Du, Peng,Assary, Rajeev S,Greeley, Jeffrey,Ferguson, Glen A,Wang, Hsien-Hau,Hassoun, Jusef,Iddir, Hakim,Zhou, Jigang,Zuin, Lucia Wiley-VCH 2013 ChemSusChem Vol.6 No.7

<P>Nonaqueous lithium-oxygen batteries have a much superior theoretical gravimetric energy density compared to conventional lithium-ion batteries, and thus could render long-range electric vehicles a reality. A molecular-level understanding of the reversible formation of lithium peroxide in these batteries, the properties of major/minor discharge products, and the stability of the nonaqueous electrolytes is required to achieve successful lithium-oxygen batteries. We demonstrate that the major discharge product formed in the lithium-oxygen cell, lithium peroxide, exhibits a magnetic moment. These results are based on dc-magnetization measurements and a lithium-oxygen cell containing an ether-based electrolyte. The results are unexpected because bulk lithium peroxide has a significant band gap. Density functional calculations predict that superoxide-type surface oxygen groups with unpaired electrons exist on stoichiometric lithium peroxide crystalline surfaces and on nanoparticle surfaces; these computational results are consistent with the magnetic measurement of the discharged lithium peroxide product as well as EPR measurements on commercial lithium peroxide. The presence of superoxide-type surface oxygen groups with spin can play a role in the reversible formation and decomposition of lithium peroxide as well as the reversible formation and decomposition of electrolyte molecules.</P>

Individual Tree Growth Models for Natural Mixed Forests in Changbai Mountains, Northeast China

Lu, Jun,Li, Fengri Korean Society of Forest Science 2007 한국산림과학회지 Vol.96 No.2

The data used to develop distance-independent individual models for natural mixed forests were collected from 712 remeasured permanent sample plots (25,526 trees) of 10-year periodic from 1990 to 2000 in Baihe Forest Bureau of Changbai Mountains, northeast China. Based on analyzing relationship between diameter increment of individual trees with tree size, competitive status, and site condition, the diameter growth models for individual trees of 15 species growing in mixed-species uneven-aged forest stands, that have simple form, good predicting precision, and easily applicable, were developed using stepwise regression method. The main variables influencing on diameter increment of individual trees were tree size and competition, however, the site conditions were not significantly related with diameter increment. The tree size variables (lnDBH and $DBH^2$) were the most significant and important predictors of diameter growth existing in all 15 growth models. The diameter increment was directly proportional to tree diameter for each species. For the competitive factors in growth model, the relative diameter (RD), canopy closure (P), and the ratio of diameter of subject tree with maximum diameter (DDM) were contributed to the diameter increment at a certain extent. Other measures of stand density, such as basal area of stand (G) and stand density index (SDI), were not significantly influenced on diameter increment. Site factors, such as site index, slope and aspect were not important to diameter increment and excluded in the final models. The total variance explained by the final models of squared diameter increment ($R^2$) for all 15 species ranged from 35% to 72% and these results compared quit closely with those of Wykoff (1990) for mixed conifer stands. Using independent data set, validation measures were evaluated for predicting models of diameter increment developed in this study. The result indicated that the estimated precision was all greater than 94% and the models were suitable to describe diameter increment.

Melt Crystallization and Morphology of Poly(p-phenylene sulfide) under High Pressure

Lu, Jun,Huang, Rui,Oh, Il-Kwon Wiley - VCH Verlag GmbH & Co. KGaA 2007 Macromolecular Chemistry and Physics Vol.208 No.4

<P>The high-pressure melt-crystallization behaviors of poly(p-phenylene sulfide) (PPS) were investigated using WAXD, DSC, TEM and SEM. PPS extended-chain crystals with c-axis thickness exceeding 4.5 µm were formed at high pressure. The DSC results showed that the melting temperature and melting enthalpy of high-pressure crystallized PPS samples were up to 327.53 °C and 94.96 J · g<SUP>−1</SUP>, respectively, which were higher than the values of ideal PPS perfect crystals used by some researchers, and the melting enthalpy of the samples fluctuated regularly during the thickening growth of the PPS crystals. Other characteristic morphologies obtained at high pressure, i.e. spherulites and rod-like crystals, were also presented with the SEM measurements.</P><P> <img src='wiley_img/10221352-2007-208-4-MACP200600526-gra001.gif' alt='wiley_img/10221352-2007-208-4-MACP200600526-gra001'> </P>

Growth of Spatial Dendrites in Bisphenol-A Polycarbonate Induced by Dioctyl Phthalate at High Pressure

Lu, Jun,Oh, Il-Kwon,Huang, Rui Informa UK (TaylorFrancis) 2009 Molecular Crystals and Liquid Crystals Vol.511 No.1

Morphology investigation on high-pressure crystallized bisphenol-A polycarbonate/dioctyl phthalate blends

Lu, Jun,Huang, Rui,Oh, Il-Kwon Wiley Subscription Services, Inc., A Wiley Company 2007 Journal of polymer science. Part B, Polymer physic Vol.45 No.19

<P>The high-pressure crystallized bisphenol-A polycarbonate/dioctyl phthalate (BAPC/DOP) blend samples were investigated using wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The specimens were prepared in a piston-cylinder high-pressure apparatus by varying the temperature, the pressure and the crystallization time for a BAPC/DOP (90/10, wt/wt) blend. The other four specimens were also prepared with different weight ratios of BAPC/DOP. The DSC results showed that the amorphous BAPC could be crystallized in 45 min by the blending with DOP and the subsequent high-pressure treatment. A wide variety of morphologies of BAPC crystals were disclosed by SEM, including spherulites, spatial dendrites, crystalbars, platelets and regular polygonal crystals of different characteristics. The folded-chain lamellar crystals were found to be the substructures of these observed BAPC microstructures. The SEM revealed a granular substructure of the lamellae in a low-crystallinity sample as well, which indicated that the crystallization of BAPC in the multiphase system might possibly agree with the model developed by Strobl. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2715–2728, 2007</P>

Fabrication and actuation of electro-active polymer actuator based on PSMI-incorporated PVDF

Lu, Jun,Kim, Sang-Gyun,Lee, Sunwoo,Oh, Il-Kwon Institute of Physics Publishing 2008 Smart materials & structures Vol.17 No.4

<P>In this study, an ionic networking membrane (INM) of poly(styrene-<I>alt</I>-maleimide) (PSMI)-incorporated poly(vinylidene fluoride) (PVDF) was applied to fabricate electro-active polymer. Based on the same original membrane of PSMI-incorporated PVDF, various samples of INM actuator were prepared for different reduction times with the electroless-plating technique. The as-prepared INM actuators were tested in terms of surface resistance, platinum morphology, resonance frequency, tip displacement, current and blocked force, and their performances were compared to those of the widely used traditional Nafion actuator. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that much smaller and more uniform platinum particles were formed on the surfaces of the INM actuators as well as within their polymer matrix. Although excellent harmonic responses were observed for the newly developed INM actuators, they were found to be sensitive to the applied reduction times during the fabrication. The mechanical displacement of the INM actuator fabricated after the optimum reduction times was much larger than that of its Nafion counterpart of comparable thickness under the stimulus of constant and alternating current voltage. The PSMI-incorporated PVDF actuator can become a promising smart material to be used in the fields of biomimetic robots, biomedical devices, sensors and actuator, haptic interfaces, energy harvesting and so on. </P>

Review—Understanding and Mitigating Some of the Key Factors that Limit Non-Aqueous Lithium-Air Battery Performance

Lu, Jun,Lau, Kah Chun,Sun, Yang-Kook,Curtiss, Larry A,Amine, Khalil The Electrochemical Society 2015 Journal of the Electrochemical Society Vol.162 No.14

<P>In this article, we have reviewed our work on understanding and mitigating some of the key factors that limit non-aqueous Li-air battery performance. Advances in Li-air battery technology require fundamental understanding of the discharge and charge processes. We first summarize an investigation of Li-air batteries based on a well-defined cathode surfaces having size-selected silver clusters. This work provided key insight into the nucleation and growth mechanism of the discharge product and its relationship to lowering charge potentials. We then describe the development of new cathode materials including ones based on Pd and Mo<SUB>2</SUB>C nanoparticles that give very low charge potentials. This work has shown that it is possible to achieve very good round-trip efficiencies as well as up to 100 cycles in a Li-air cell. Finally, we discuss investigations of likely sources of electrolyte decomposition at the cathode and anode, which need to be resolved in order to achieve the long cycle life that is necessary to enable Li-air batteries.</P>

Short-Hairpin RNA-Mediated MTA2 Silencing Inhibits Human Breast Cancer Cell Line MDA-MB231 Proliferation and Metastasis

Lu, Jun,Jin, Mu-Lan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Objective: To observe the effects of metastasis-associated tumor gene family 2 (MTA2) depletion on human breast cancer cell proliferation and metastasis. Methods: A short-hairpin RNA targeting MTA2 was chemically synthesized and transfected into a lentivirus to construct Lv-shMTA2 for infection into the MDA-MB231 human breast cancer cell line. At 48 hours after infection cells were harvested and mRNA and protein levels of MTA2 were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, respectively. Cell viability and metastasis were assessed by CCK-8, wound-healing assay and Transwell assay, respectively. In addition, a xenograft model of human breast cancer was constructed to investigate cancerous cell growth and capacity for metastasis. Results: After infection with Lv-shMTA2, mRNA and protein levels of MTA2 was significantly reduced (p<0.05) and MDA-MB231 cell proliferation and metastasis were inhibited (p<0.05). In addition, mean tumor size was smaller than that in control group nude mice (p<0.05) and numbers of metastatic deposits in lung were lower than in control group mice (p<0.05). Depletion of MTA2 affected MMP-2 and apoptosis-related protein expression. Conclusions: For the first time to our knowledge we showed that MTA2 depletion could significantly inhibit human breast cancer cell growth and metastasis, implying that MTA2 might be involved in the progression of breast cancer. The role of MTA2 in breast cancer growth and metastasis might be linked with regulation of matrix metalloproteinase and apoptosis.