Effects of contact shape on ballistic phonon transport in semiconductor nanowires

Jing-Jing Yao,Wei-Qing Huang,Gui-Fang Huang,Yuan Chen,Ling-Ling Wang,Wangyu Hu,Anlian Pan 한국물리학회 2012 Current Applied Physics Vol.12 No.2

We study the effects of contact shape on ballistic phonon transport in semiconductor nanowires at low temperatures using an approximative scalar model of continuum elasticity. Five different contacts connected to two semiconductor nanowires with different transverse widths are discussed. Numerical results show that the contact shape acts as an ‘acoustic impedance adaptor’, playing a crucial role on the ballistic phonon transmission and thermal conductance. The phonon coupling in the contacts with certain length facilitates ballistic phonon transmission compared to the abrupt interface, in which the phonon scattering is the strongest. It is found that the more the contact is abrupt, the smaller the thermal conductance is. The catenoidal contact rather than the abrupt interface is also the competitive candidate to obtain bigger thermal conductance. These results indicate that choosing an appropriate contact shape is one of the most critical factors to accurately measure the thermal conductance with a very high precision and reliability in different temperature ranges at low temperatures.

Developing an Integrated Approach Toward Ballistic Missile Proliferation

( Jing Dong Yuan ) 한국국방연구원 2005 The Korean Journal of Defense Analysis Vol.17 No.2

Ballistic missile proliferation remains a serious threat to regional security and stability. While the post-Cold War era has seen a steady decline in the total number of long-range ballistic missiles, the few countries with active ballistic missile programs tend to concentrate in regions of ongoing and latent conflicts and are themselves either de facto or aspiring nuclear weapon states. Past efforts at stemming ballistic missile proliferation through technology denial and controls, such as the Missile Technology Control Regime (MTCR), have achieved notable success. However, with continuing spread and maturation of missile technologies and the emergence of indigenous capabilities, strategies based solely on export controls must be supplemented by efforts at developing norms for restraints in ballistic missile procurement and use. This article reviews and evaluates the various norms building initiatives such as the HCoC, GCS, and UNGEP and suggests that an integrated approach should be developed that addresses both the demand and supply factors in missile proliferation. Such an approach would ideally be holistic in conceptualization and synergetic in execution at the domestic, regional, multilateral, and global levels through transparency and confidence building, as well as denial strategies that raise the cost, delay, and ultimately prevents the acquisitions of longer-range ballistic missiles.

A Comparison of the Fitness Functions to Identify the Motor-Table System: Simulations and Experiments

Yuan-Chou Jing,Kun-Yung Chen 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.4

The different state-error fitness functions (FFs) are proposed and compared numerically and experimentally to identify a motor-table system by using self-learning particle swarm optimization (SLPSO). Firstly, the completed mathematical model containing both of mechanical and electrical equations is successfully formulated. Secondly, the FFs containing different state-errors are compared by using PSO and SLPSO to identify the unknown parameters. It is found that the identify performance of the SLPSO algorithm by using FF with full-state error of displacement, velocity and current is the best than the other methods. Thus, the FF with full-state errors is adopted in experiments for a real mechatronic motor-table system. Then, the unknown parameters are successfully identified by the SLPSO algorithm. The contributions of this paper are: (1) the more states of the system are measured and used in the FF, the more parameters of system are accurately identified by the proposed identification approach, (2) the FF with full-state errors is performed in a real mechatronic motor-table system, and the unknown parameters are successfully identified by the SLPSO algorithm in experimental results.

The Study of China’s Military Strategy and Satellite Development: Moving Toward “Winning the Informationized War Globally”?

Yuan-Chou Jing 한국국방연구원 2019 The Korean Journal of Defense Analysis Vol.31 No.1

China’s military strategy has evolved across different leaders’ eras. Even though China’s military strategic guideline always stays on the track of “active defense,” the essence has been shifting from tradition to informationization. Since satellites are able to provide space information support so as to fulfill informationization, once informationization becomes the focus of military strategy, it is supposed to bring momentum to the research and development of satellites. Therefore, satellite development can be considered as an index to check whether the military strategy is being implemented or not. China is continuously making progress in satellite development. Especially since the informationization was included in the guideline in the Hu Jintao era, satellites started to be able to conduct space information support missions. In conclusion, China is sincerely fulfilling its military strategy through consistent satellite development. On the other hand, “local war” is another focus of strategic guidelines, it implies that China considers its national interests mainly concentrated on this region so far. However, while China’s interests are expanding globally, China will need to cultivate its global dominance based on rapid satellite development to safeguard the global interest; “Winning the informationized war globally” might be the next focus.

The People’s Liberation Army Rocket Force in Space Warfare: With Available but Incomplete Capabilities

( Yuan-chou Jing ) 한국국방연구원 2021 The Korean Journal of Defense Analysis Vol.33 No.3

Based on the military struggle readiness of Winning Informationized Local Wars, the PLA has underscored the need for dominance in space, looking for a privileged and commanding status in the context of space warfare. To further dictate the whole war, the PLA is currently devoted to the development of anti-satellite weapons (ASAT) to substantiate its Space Control Capability. The correlation between the PLARF and anti-satellite operations can be seen from two aspects. First, transformation of the military strategy towards the ideal of having both nuclear and conventional capabilities and deterring wars in all battlespaces in the wake of the recent military overhaul of the PLA markedly revealed Beijing’s unwavering intent to force its influence into space. Second, empirical data of the PLARF’s “reconnaissance, control and strike” joint construct and operational equipment showed that the PLARF has entered the developmental stage capable of undertaking successful anti-satellite operations. This study concludes that the PLARF is in charge of anti-satellite operations and then conduct this mission with the vertical commanding architecture from the Central Military Commission, Theatres, down to the PLARF units. This study also argues that for now and the foreseeable future, the PLA will focus all its efforts to integrate information links of the combat systems and extend the range of conventional ballistic missiles.

Threat Perception and Chinese Security Policy after the Cold War

Yuan, Jing-dong The Center for International Studies, Inha Univers 1998 Pacific Focus Vol.13 No.1

SINO-RUSSIAN CONFIDENCE-BUILDING MEASURES : A PRELIMINARY ANALYSIS

Yuan, Jing-dong the Institute for Far Eastern Studies, Kyungnam Un 1998 인문과학연구 Vol.4 No.-

The recently concluded Sino-Russian agreements on resolving border disputes and on force reductions provide an interesting case study of how confidence-building measures(CBMs), both as a process and as outcomes of bilateral negotiations between former adversaries, can contribute to regional security and stability. Sino-Russian CBMs, while incorporating many of the features of the European model, are nevertheless unique in their development. Their integration into the security framework has been facilitated by an overall improving bilateral politico-economic relationship and the political commitments from the two countries' the leadership. The evolution of these CBMs has been marked by incrementalism, informality, and unilateral asymmetric disarmament on the part of the Soviet Union/Russia. The longer-term test of their tenacity will probably depend on future developments in the Sino-Russian political relationship-a relationship that, for the time being, remains one of convenience and is based on short-term in interests.

Muscle fatigue: general understanding and treatment

Jing-jing Wan,Zhen Qin,Peng-yuan Wang,Yang Sun,Xia Liu 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Muscle fatigue is a common complaint in clinical practice. In humans, muscle fatigue can be defined as exercise-induced decrease in the ability to produce force. Here, to provide a general understanding and describe potential therapies for muscle fatigue, we summarize studies on muscle fatigue, including topics such as the sequence of events observed during force production, in vivo fatigue-site evaluation techniques, diagnostic markers and non-specific but effective treatments.

First-principles Study of the Electronic Structure of Nonmetal-doped Anatase TiO2

Yuan Wang,Jing Ma,Jian-Ping Zhou,Xiao-Ming Chen,Jing-Zhou Wang 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.3

In this paper, we present a detailed study of the structure, defect formation energy, and electronic and magnetic properties of nonmetal-doped TiO2 by using the first-principles projector augmented wave (PAW) potential within the generalized gradient approximation (GGA). The formation energy reduces with increasing electronegativity of the dopant. After doping with nonmetal elements, some band gaps of the doped-TiO2 become narrow, and others become wide, in which impurity states appear in the band gap. The relative positions of the impurity states are much different, mainly caused by the different electronegativities of the nonmetal elements F, O, B, C and N. When H is added to achieve a charge balance, the impurity states approach the valence band maximum, because the electronegativity difference among the nonmetal elements is decreased. Therefore, nonmetal and H codoping is an effective way to improve the visible-light catalytic activity of anatase TiO2. In addition, N-doping and C-doping can cause spin polarization of the TiO2 electronic structure and form 1.0 μB and 2.0 μB magnetic moment, respectively.

Association Between C1019T Polymorphism in the Connexin 37 Gene and Helicobacter Pylori Infection in Patients with Gastric Cancer

Jing, Yuan-Ming,Guo, Su-Xia,Zhang, Xiao-Ping,Sun, Ai-Jing,Tao, Feng,Qian, Hai-Xin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Objective: To investigate the association between the connexin 37 C1019T polymorphism and Helicobacter pylori infection in patients with gastric cancer. Methods: 388 patients with gastric cancer (GC), 204 with chronic superficial gastritis (CSG) were studied. H. pylori was detected by gastric mucosal biopsies biopsy dyeing method. Connexin 37 gene polymorphism 1019 site genotypes were determined by gene sequencing technology. Genotypes and alleles frequencies were compared. Results: (1) Connexin37 gene 1019 site distribution frequency (CC type, TC type, TT type) in the CSG group was 18.1%, 45.1% and 36.8%; in the stomach cancer group it was 35.1%, 45.9% and 19.%, conforming to the Hardy-Weinberg euilibrium. (2) In comparison with CSG group, the frequency of Connexin37 C allele was higher in the gastric cancer group (58.0% vs 40.7%, OR = 2.01, 95%CI = 1.58-2.57, P < 0.01). The prevalence of gastric cancer risk was significantly increased in the carriers of C allele (CC+TC) than in TT homozygote (OR = 2.47, 5%CI = 1.68- 3.610. (3) Gastric cancer patients complicated with Hp infection 211 cases, gastric cancer group of the male patients with HP positive patients with 187 cases, 40 cases of female patients with negative patients, 24 cases were HP positive, negative in 137 cases, control group male patients, 28 cases were Hp positive, negative in 95 patients, female patients with Hp positive 6 cases, 75 cases were negative. On hierarchical analysis, the male group OR value was 15.9 (95%CI to 9.22-27.3), and the female OR was 2.19 (95%CI 0.88-5.59), indicating a greater contribution in males (P <0.01). After elimination of gender effects, positive HP and gastric cancer were closely related (OR 8.82, 95% CI: 5.45-14.3). (4) The distribution frequency of C allele in patients with Hp infection was much higher than that in Hp negative cases in the GC group (64.5% vs 47.0%, OR = 2.05, 95%CI = 1.54-2.74, P < 0.01). Compared with TT homozygotes, (CC+TC) genotype prevalence of gastric cancer risk increased significantly (OR = 2.96, 5%CI = 1.76-2.99 ). Conclusion: The T allele in the connexin37 gene might not only be associated with gastric cancer but also with H. pylori infection.