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This paper discusses the impact of the adjacent channels on the 1-dB compression point, the IP3 and the IP5 of Radio Frequency (RF) amplifier by n-tone test. By combining the theoretical derivation and software simulation, the model analysis for the third/five order polynomial nonlinear amplifier has been achieved. Moreover, the control variable method is adopted to draw the curves for the input/output signals. The research shows that the 1-dB compression point, the IP3 and the IP5 drop as n increases, and they all have symmetry for a given n. The fifth-order polynomial nonlinear amplifier model is proposed, the research shows that the adjacent channels have a great impact on the 1-dB compression point, the IP3 and the IP5 of the desired channel. This effect must be taken into account in actual RF amplifier designs and wireless communication architectures.

In order to design a programmable multipath waveform generator, VHDL is used to design every module. It is consisted with the waveform input, FPGA module, digital-to-analog conversion (D/A) module, display circuit. By pressing the keys, eight waves can be chosen and shown in the oscilloscope. With the characteristics of low cost, portable and expandable, it can be widely used in electronic circuit system.

In order to solve the reality of the traditional manual operation and further improve the accuracy and efficiency of the flag raising, an automatic flag lifting system is designed based on the single-chip embedded technology. It is consisted with the single-chip micro-controller minimum system, motor circuit, key circuit, LCD display circuit, voice control circuit, DC circuit. By pressing the button, the national flag begin to rise and fall with playing the national anthem at the same time. The system has the advantages of low price, high stability and simple operation.

The direct torque control (DTC) system of the traditional asynchronous motor has many disadvantages, such as complex modeling and large amount of calculation, In order to improve the dynamic performance of the DTC system of the asynchronous motor, a direct torque control system is put forward. It uses space vector analysis method to calculate electromagnetic torque and stator flux linkage of asynchronous motor directly, follows the change of the stator flux linkage and torque, omits the complicated calculation, reduces the dependence on motor parameters. The simulation model of the DTC system of the asynchronous motor was established using SIMULINK software package. The feasibility of method is proved in theory, The results of simulation show that the modeling and simulation of the system has good static and dynamic performance, control precision of the system is higher, the stability is better.

The UML model of database is a frame foundation of developing a database, this paper recommends a way to build data model based on the urban heating pipe networks by using VISIO[1] modeling tools. There are two ways that Use Case Diagram and Static Structure Diagram. The article describes the function of database application system, data structure and relationship on the heating-pipe network. The data structure model makes it more clear and lower redundancy when the developers are developing an application system of database.

The power energy storage in battery transfers to capacitors through thyristor in hybrid energy storage, which makes the instantaneous power amplified. As the switch in Hybrid energy storage, the thyristor must satisfy its opening requirements , besides, the characteristics of the hybrid energy storage system is considered to design the width of trigger pulse, otherwise the thyristor can’t be opened that leads to failure of energy transfer. In this paper, the model of the system is established, the function of current to time is derived from the model, and then the minimum width of trigger pulse is calculated out. The simulation and experiment results are presented, which match with the designation well.

Objective: To determine the correlation between differential leukocyte counts and hyperglycemic emergencies. Methods: Fifty patients with diabetic ketoacidosis (DKA), 50 patients with diabetic ketosis (DK), 50 non-DK diabetic patients with stable glycemic control, and 50 normal controls were enrolled. Their total and differential leukocyte counts were measured and evaluated at admission and after treatment. Results: The patients with DKA and DK had higher plasma glucose levels (20.84±6.73 mmol/L, 15.55±2.6 mmol/L, respectively) and more median leukocytes (13325/mm3 and 6595/mm3, respectively) and median neutrophils (11124 /mm3 and 4125/mm3, respectively) but fewer median eosinophils (28/mm3 and 72/mm3, respectively) compared to non-DK and control groups (all p < 0.05). Acute infection increased the elevating extent. The median leukocyte counts in DK and non-DK patients (6595/mm3 and 6008/mm3, respectively) were within the normal range. The counts of total leukocytes and neutrophils were significantly higher but eosinophils lower in severe DKA cases than in mild/moderate cases (p < 0.05). When the DKA and DK and infection resolved, total leukocytes and neutrophils fell, but eosinophils increased. The counts of total leukocytes, neutrophils, and monocytes were negatively correlated with arterial pH levels (r = -0.515, r = -0.510, r = -0.517, all p < 0.001, respectively) and positively correlated with plasma glucose levels (r = 0.722, r = 0.733, r = 0.632, all p < 0.05, respectively) in DKA patients. The arterial pH level was the most significant factor affecting total leukocytes in DKA (β = 0.467, p = 0.003). The diagnosis analysis showed that higher total leukocyte and neutrophil counts and lower eosinophil counts had a significant ability to reflect the presence of hyperglycemic emergencies. Conclusion: More total leukocytes and neutrophils but fewer eosinophils was significantly correlated with DKA and DK. Leukocyte counts can add valuable information to reflect the presence of hyperglycemic crisis and acute infection.

A two-stage power amplifier (PA) using GaN HEMTs is presented with a high power added efficiency (PAE) and good linearity. This PA employs a structure of a class-C PA driving a class-AB PA to obtain a high PAE while maintaining the linearity. Source-pull and load-pull techniques were implemented to achieve optimum output impedance and inter-stage matching condition to compromise the PAE and the linearity of the overall circuit. When producing a two-tone carrier-to-intermodulation (C/I) ratio of 30 dB with the 1 MHz space, the two-stage PA exhibits a maximum PAE of 47% with an output power of 3 W at 3.7 GHz. The PA provides a maximum output power of 7 W with the gain of 15.8 dB.

To satisfy the continuously increasing demand for high data rates and mobility required by new wireless applications, the 5G has gained much attention recently. Radio frequency power amplifiers (RF-PAs), as one of critical components of 5G transmitter system, are becoming a hot issue. In this paper, the statistical analysis on RF PA papers shows the research on RF-PAs in Asia-Pacific and cooperation between different affiliations and countries are gradually becoming more prominent, showing the globalization trend of RF PA research and the 5G technologies. The decreased research cycle of RF PA shows the processes of research on PA and 5G technologies are speeding up. Some promising RF-PA technologies for 5G wireless communication system are also been discussed.

We performed this study to examine the effect of electro-acupuncture (EA) on postoperative pain, postoperative nausea and vomiting (PONV) and recovery in patients after a supratentorial tumor resection. Eighty-eight patients requiring a supratentorial tumor resection were anesthetized with sevoflurane and randomly allocated to a no treatment group (Group C) or an EA group (Group A). After anesthesia induction, the patients in Group A received EA at LI4 and SJ5, at BL63 and LR3 and at ST36 and GB40 on the same side as the craniotomy. The stimulation was continued until the end of the operation. Patient-controlled intravenous analgesia (PCIA) was used for the postoperative analgesia. The postoperative pain scores, PONV, the degree of dizziness and appetite were recorded. In the first 6 hours after the operation, the mean total bolus, the effective times of PCIA bolus administrations and the VAS scores were much lower in the EA group (p < 0.05). In the EA group, the incidence of PONV and degree of dizziness and feeling of fullness in the head within the first 24 hours after the operation was much lower than in the control group (p < 0.05). In the EA group, more patients had a better appetite than did the patients in group C (51.2% vs. 27.5%) (p < 0.05). The use of EA in neurosurgery patients improves the quality of postoperative analgesia, promotes appetite recovery and decreases some uncomfortable sensations, such as dizziness and feeling of fullness in the head.

Altered expression of TROP2 is observed in various types of human cancers. However, the clinical significance and pathological role of TROP2 in gallbladder cancer (GBC) remains unclear. The main objective of this investigation was to clarify the relationships between TROP2 expression and the clinicopathological features of patients with GBC. Immunohistochemistry was performed to investigate the expression of TROP2 and epithelial-mesenchymal transition (EMT) indicator proteins in 93 patients with GBC. Immunohistochemistry showed that the protein expression level of TROP2 was significantly higher in GBC tissues than in adjacent noncancerous tissues. In addition, immunohistochemistry analysis showed that TROP2 expression was significantly correlated with histologic grade (P=0.038), tumor stage (P=0.015), and lymph node metastasis (P=0.007). Furthermore, high TROP2 expression was significantly associated with a loss of the epithelial marker E-cadherin (P=0.013) and acquisition of expression of the mesenchymal marker vimentin (P=0.031). Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between TROP2 expression and prognosis of GBC patients. Kaplan-Meier analysis indicated that patients with high TROP2 expression had poor overall survival (P

Considering interaction of tunnel-soil-building, the masonry structure building with strip foundation crossed by shield tunnel in 45 degree was simulated by 3D FEM MIDAS/GTS software. The settlement and strain of building was analyzed. The results show that: the building was slightly uplifted first, and then followed by rapid settlement during shield tunnel excavating. Uneven settlement was still existed when settlement was stable, so there was permanent distorted deformation in building. The maximum shear strain of wall decreased slightly first, and then increased rapidly, at last decreased slightly after it reached the peak. The plastic zone of wall was concentrated at the top of wall cross position when the building had two or three floors. With the increasing of axis distance between tunnel and building from zero, the foundation tilted toward the tunnel axis side, and settlement decreased generally. The maximum shear strain of wall first increased and then decreased. The effect of shield tunneling construction could be ignored when distance between tunnel axis and foundation was more than 1.8i. With the increasing of building floors, the foundation additional settlement increased to a lesser extent, and the maximum shear strain of wall increased rapidly, but the difference divided by its initial value was decline. When building had more than 4 floors the maximum shear strain of wall was dangerous, and maximum plastic zone of wall would change.

In this paper, an empirical nonlinear model for high electron mobility transistors (HEMTs) is presented. Unlike the conventional large-signal models whose fitting parameters are coupled to the measured I-V and C-V characteristics, the proposed modeling equations are direct formulated from the second-order derivative of drain current (I-V) and gate charge (Q-V) with respect to gate voltage. As a consequence, the proposed large-signal model is kept continuously differentiable and accurate enough to the higher-order I-V and Q-V derivatives. Measured and modeled results are compared for the 0.25µm gate-length GaAs pseudomorphic HEMTs (pHEMTs), and good agreement is obtained.

The characteristics of the remote fault diagnosis (RFD) is analyzed, the levels of the diagnostic participators, diagnostic processes, system structure, and the responsibilities and obligations for founding and maintaining RFD system are pointed out. The multi-level RFD system with the local, remote and domain fault diagnosis subsystem is designed. The system fully accords with RFD's characteristics, supports the graded fault diagnosis and is convenient to ensure the diagnosed equipment. The system is realized with Internet, LAN, PSTN, GSM communication network and database techniques, which is in favor of exerting the excellence of various communication networks, founding and widely applying RFD system.