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Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Pipelines with undulating profiles are susceptible to liquid accumulation at low-lying positions along their route,particularly when utilized for gathering and transmission of wet natural gas and transmission of oil-gas blends. Considering the significant difference in inclination angle between gathering and transmission pipelines and gas wells, foam drainage technology, already wellestablished for the removal of liquid accumulation from gas wells, needs to be further demonstrated before its application to transmission pipelines carrying oil-gas blends. [Methods] Gas-liquid multiphase pipe flow experiments were conducted using an experimental loop setup,aimed at investigating the impact of foam on the characteristics of gas-liquid multiphase flow at various inclination angles and elucidating the mechanism of plug formation in foam-containing multiphase flow. Additionally, the study examined the impact of changes in foam system properties induced by the presence of inorganic salts on the characteristics of foam-containing multiphase flow. Flow regime-specific analysis was conducted on flow characteristic parameters and pressure difference features. [Results] In pipelines with undulating profiles and significantly different inclination angles compared to gas wells, the addition of surfactant was found effective in removing accumulated liquid and mitigating the occurrence of sectional slugged flow conditions. To investigate the drainage effect of water-based Sodium Dodecyl Sulfate(SDS) foam under the influence of inorganic salts, a further study was conducted with the presence of NaCl and MgCl2 as environmental impact factors, and using metal grid sensors, a high-speed camera system, and pressure sensors. The findings revealed that the variation in foam properties resulting from the effect of inorganic salts had a substantial impact on the efficiency of foam drainage. Furthermore, it was observed that an excessive formation of stable foam within the pipeline caused a substantial increase in pressure drop along the route.[Conclusion] When applying foam drainage technology to gathering and transmission pipelines with liquid accumulation, stability becomes a critical factor in selecting an appropriate foam system. Further research should focus on investigating the relationship between the influence of the foam layer on the flow characteristics of the medium in pipelines and the overall performance of the foam system.

Copyright of Journal of Vibration, Measurement & Diagnosis is the property of Nanjing Hangkong Daxue and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: As a classic surgical method for the treatment of femoral head necrosis and femoral neck fracture, total hip arthroplasty has some problems, such as poor placement of prosthesis, postoperative dislocation and so on. OrthoPilot navigation assisted total hip arthroplasty can theoretically improve the accuracy and safety of prosthesis placement. At present, there are few studies on its application in total hip arthroplasty in China. OBJECTIVE: To explore the feasibility and short-term clinical effect of OrthoPilot navigation assisted total hip arthroplasty. METHODS: A retrospective analysis was performed in 23 patients who received OrthoPilot navigation assisted total hip arthroplasty in the Department of Joint surgery of the First Affiliated Hospital of Anhui Medical University from June 2019 to April 2022. A total of 23 patients with freehand total hip arthroplasty were matched at 1:1 according to sex, age, body mass index and preoperative Harris score. The anteversion and inclination angles during and after operation were measured and counted. The operation time, total blood loss, postoperative drainage, average hemoglobin loss and postoperative Harris scores were calculated. RESULTS AND CONCLUSION: (1) The operation time in the navigation group was (152.4±39.9) minutes and in the non-navigation group was (115.3±35.4) minutes, with statistically significant (P=0.02). (2) In terms of angle measurement, the anteversion angle of acetabular cup was (42.3±3.5)° during operation and (42.6±5.5)° after operation, with no significant difference (P=0.574) in the navigation group. The inclination angle of acetabular cup was (18.5±3.4)° during operation and (19.3±3.9)° after operation, with no significant difference (P=0.567) in the navigation group. (3) According to “Lewinnek safe zone”, 22 hips were in the safety zone and 1 hip outside the safety zone after operation in the navigation group, while 17 hips were in the safety zone and 6 hips outside the safety zone after operation in the non-navigation group, showing a significant difference (χ ² =4.212, P=0.04). (4) In terms of surgical treatment, there was no significant difference in total blood loss, postoperative drainage, average hemoglobin loss, Harris score, and the incidence of postoperative lower extremity deep venous thrombosis between the two groups. (5) The average follow-up was 3 months after operation, and there were no patients with early infection or dislocation in the two groups. (6) These results verify that OrthoPilot navigation assisted total hip arthroplasty can improve the accuracy and safety of acetabular cup placement, and its short-term clinical effect is not significantly different from that of freehand total hip arthroplasty. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Cone beam computed tomography (CBCT) technology was used to measure the inclination angle of mandibular molars before and after orthodontic treatment of Angle Class Ⅰ and skeletal class malocclusion, in order to obtain the ideal range of inclination angle of mandibular molars after orthodontic treatment of malocclusion patients, improve the curative effect. Methods The CBCT scanning data of 28 patients with angle class Ⅰ and skeletal class Ⅰ malocclusion were screened, and the images were corrected, reconstructed and measured. The mesial and distal inclination angles of mandibular molars were measured and statistically analyzed. Results The initial inclination angles of the mandibular first molar and mandibular second molar before orthodontic treatment were (13.9 ± 6.07)° and (19.0 ± 7.64)°, and the postoperative inclination angles of the mandibular first molar and mandibular second molar were (10.8 ± 6.07)° and (15.0 ± 8.38)° respectively. There is a statistical difference between the inclination angles of the mandibular first molar and second molar before and after treatment. There was no statistical difference in the initial inclination angle of mandibular molar inclination between adults and juveniles and also no statistical difference between patients with different mandibular plane angle patterns. Conclusion CBCT can directly, conveniently and accurately measure the axial inclination of mandibular molars, and obtain the ideal axial inclination range of mandibular first and second molars which is necessary for orthodontics. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Steam condensation in the presence of air is an important thermal-hydraulic phenomenon in containment under loss of coolant accidents (LOCAs) or main steam line break accidents (MSLBs). Previous studies have focused on the effects of thermal parameters such as air mass fraction, gas pressure and sub-cooling on heat transfer characteristics, but less on the influence and action principle of geometric parameters such as tube length, tube diameter and inclination angle. Fully understanding the influence of geometric parameters on condensation heat transfer of steam containing air is of great significance for efficient heat transfer, so as to improve the safety and economy of related applications. The effects of tube diameter (4-60 mm), tube length (0.1-7 m) and inclination angle (0°-90°) on condensation heat transfer characteristics of air containing steam were studied based on the diffusion boundary layer condensation mechanism model by using three-dimensional CFD numerical simulation method. The results show that the tube diameter, tube length and inclination angle have significant effects on condensation heat transfer characteristics of air containing steam. However, when tube diameter exceeds 30 mm, tube length exceeds 1 m and inclination angle exceeds 60°, the average condensation heat transfer coefficient is no longer sensitive to the change of geometric parameters. The average condensation heat transfer coefficient decreases with the increase of tube diameter, and the descent speed decreases rapidly. When the tube diameter is 4 mm, the average condensation heat transfer coefficient is twice that of 60 mm. It first decreases and then increases with the increase of tube length, and reaches the minimum value at about 3 m. And it increases with the increase of inclination angle. The high concentration air layer near the wall is the main thermal resistance in the condensation process of steam-air, and its thickness makes a good negative correlation with condensation heat transfer coefficient. The high concentration air layer will first accumulate and thicken along the tube wall, and then produce a certain negative pressure due to the high density and high flow rate of mixed gas near the wall, so as to form a transverse velocity, so that the air layer will be thinned slowly after 1 m from the top of the pipe. Thus, the local condensation heat transfer coefficient decreases rapidly at first and then increases slowly along the direction of tube length. In addition, the tube circumferential local condensation heat transfer coefficient is uneven obviously under the inclined arrangement, the heat transfer on the upper surface is significantly enhanced due to the thinning of air layer by natural convection scouring and falling off, and gradually weakened to both sides, while the lower surface forms a stagnation zone due to the obstruction of the tube wall, which causes the accumulation and thickening of the air layer, resulting in a certain heat transfer inhibition. Compared with the vertical tube, about 75% of the circumferential area has different degrees of heat transfer enhancement, and only the dorsal flow surface has a certain heat transfer inhibition.

In the context of wave-current, the characteristics of vortex structure and wave propagation around the upstream inclined pile differ significantly than around the vertical pile, which affects the local scour process of the pile foundation. To better understand the characteristic of local scour around upstream inclined piles under the joint action of wave and current, local scour tests were carried out in the wave- current flume for the upstream inclined piles with different inclination angles. Besides, a preliminary investigation was conducted into the ephemeral characteristics of local scour depth, influencing factors, and the characteristics of bed morphology. As suggested by the research results, the local scour depth of upstream inclined piles is smaller compared to vertical piles under the context of clear water scour at all times. The equilibrium scour depth decreases progressively, and the relative time scale (T ∗ 0 )shows an incremental increase when the pile inclination rises. Besides, the width of scour hole is smaller compared to vertical piles, showing a teardrop-like shape, while the dune after the tail exhibits a longer single-peaked band structure with a more significant irregularity. Despite a close correlation between the depth of local scour and Froude number, the wave deformation caused by upstream inclination makes it more difficult to determine the specific function of scour depth, radio of velocities and Keulegan-Carpenter number. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Engineering Science / Gongcheng Kexue Yu Jishu is the property of Advanced Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advanced Engineering Science / Gongcheng Kexue Yu Jishu is the property of Advanced Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To investigate the accuracy and effectiveness of acetabular cup placement in total hip arthroplasty (THA) after lumbar fusion applying of modified acetabular anteversion and inclination angles test system., Methods: A clinical data of 45 patients undergoing THA for osteoarthritis between January 2018 and June 2023 was retrospectively analyzed. All patients had previously received lumbar fusion. The modified acetabular anteversion and inclination angle test system was used in 26 cases (observation group) and not used in 19 cases (control group) during THA. There was no significant difference in baseline data such as gender, age, body mass index, operative side, number of lumbar fusion segments, and preoperative Harris score between the two groups ( P >0.05). The position of acetabular prosthesis, hip function (Harris score), and incidence of complications were compared between the two groups., Results: In the observation group, all acetabular cups were in the safe zone (anteversion angle, 25°-30°) during operation, and 1 acetabular cup (3.85%) was not in the safe zone after operation. In the control group, 9 acetabular cups (47.37%) were not in the safe zone. The postoperative difference between the two groups was significant ( P <0.05). There was no significant difference between intra- and post-operative acetabular inclination angles in the observation group ( P >0.05), and the postoperative acetabular inclination angle was significantly smaller in the observation group than in the control group ( P <0.05). All incisions healed by first intention and no infection occurred. All patients were followed up 6 months. There was no significant difference in Harris score between the two groups at different time point ( P >0.05), and there were significant differences between different time points in the two groups ( P< 0.05). No joint dislocation occurred in the observation group during follow-up, while dislocation occurred in 2 cases and femoral impingement syndrome occurred in 1 case of the control group. There was no significant difference in the incidence of complications between the two groups ( P >0.05)., Conclusion: For THA patients with lumbar fusion, the ideal placement angle of the acetabular cup can be obtained by using the modified acetabular anteversion and inclination angles test system during operation.

The effects of the combination of joint density and inclination on the strength and deformation characteristics of rocklike specimens containing open joints were studied by using uniaxial compression tests. The following conclusions were made:with the increase of joint inclination, the stress-strain curve changes from a multi-peak value to a single peak value and the brittleness of the specimen enhances, whereas the ductility of the specimen weakens. The influence of joint density on the unified peak strength is related to the size of joint inclination, and the effect of joint density on the unified modulus shows a "V" shape, namely, the unified elastic modulus first decreases and then increases with the increase of joint density. With the increase of joint inclination, the unified elastic modulus increases gradually and its maximum value, which achieves 70%-80% of the complete specimens' elastic modulus, appears at 90° of joint inclination. The joint inclination is the major influencing factor on the unified peak strength and the unified elastic modulus of the rock-like specimens containing many joints. Further analysis on the test results demonstrates that the transformation law of the relationship between the joint density or joint inclination and the stress-strain curve, as well as the unified peak strength and the unified elastic modulus, is related to the failure process of the specimen. The failure mode of the specimen can be classified into three categories:tension failure, shear failure, and mixed failure.

The semi-submersible barge is taken as the research object. The four-corner draught sensors are installed in its four corner cabins and the longitudinal and transverse inclinations of the semi—submersible barge could be deduced by the four-angle draught value to monitor the attitude of the ship in real time. At the same time, the Compass software of China Classification Society was used to calculate the ultimate trim angle and roll angle of caisson loaded by "Guangzhou" semi — submersible barge, and the results would be compared with the design limit value of the ship to achieve the safety of semi-submersible barge for the purpose of early warning. The test shows that the method can quickly and intuitively monitor the stability and safety of semi—submersible barge operation. This method can be applied to similar engineering ships and has a broad market prospect. [ABSTRACT FROM AUTHOR]

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Machining deformation is the main factor to determine the machining quality and efficiency. For the machining deformation of thin-walled blade, the inclination angle of cutter in milling is analyzed. A deformation model of cutter-workpiece cutting force system is proposed, which can be used to predict the deformation of thin-walled blade. The appropriate tool paths and processing technics are planned to control the machining deformation of thin-walled blade. Contrast experiments of machining aluminium alloy 7075 at different inclination angles are carried out, and the cutting force, residual stress and machining deformation are measured and analyzed. The result shows that the actual deformation law of thin-walled blade is consistent with the predicted results, and the optimal inclination angle of cutter is 15°-20°. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For real-time monitoring vertical posture of hoister containers, an attitude sensing system of hoister container based on ADXL345 was designed in order to ensure timely alarm when the hoister container is inclined. The system determines current attitude of hoister container by monitoring its inclination angle in perpendicular direction. The inclination angle is compared with alarm threshold, if it goes beyond alarm threshold, makes alarming. The alarming information can be uploaded to the hoister monitoring center via RS485, so as to achieve early warning operation.

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To compare the difference in the inclination and anteversion angles of the acetabular cup measured by intraoperative robot-assisted total hip arthroplasty (THA) and postoperative X-ray films and CT imaging., Methods: The clinical data of 54 patients (54 hips) who underwent robot-assisted THA between May 2020 and December 2020 were retrospectively analyzed. Among them, there were 26 males (26 hips) and 28 females (28 hips), with an average age of 58.4 years (range, 39-71 years). The body mass index was 19.2-29.3 kg/m 2 , with an average of 25.2 kg/m 2 . All the patients had their first THA, including 31 cases of osteonecrosis of the femoral head, 12 cases of hip arthritis, 8 cases of femoral neck fracture, and 3 cases of developmental dysplasia of the hip. The anteversion and inclination angles of the acetabular cup were obtained through the surgical data in the robot host system. All patients underwent X-ray and CT scan examination within 2-7 days after operation to obtain the postoperative anteversion and inclination angles of the acetabular cup. According to the concept of "Lewinnek safe zone", the proportion of acetabular in the safe zone intra- and post-operation were compared., Results: The operation time was 57.8-89.2 minutes, with an average of 68.3 minutes; the intraoperative blood loss was 125.0-450.0 mL, with an average of 204.8 mL. No adverse events such as dislocation of hip joint and infection occurred during hospitalization. The anteversion angle of acetabular cup was (40.8±0.6)° during operation and (41.2±2.8)° after operation, with no significant difference ( t =1.026, P =0.307). The anteversion angle of acetabular cup measured during operation was (17.6±1.4)°, which was significantly smaller than that measured after operation (23.4±3.8)°( t =10.520, P =0.000). According to "Lewinnek safe zone", 54 hips (100%) were in the safety zone during operation, and 16 hips were out of the safety zone, 38 hips were in the safty zone after operation, the ratio of the hips in the safty zone was 70.4%, showing a significant difference ( χ 2 =18.783, P =0.000)., Conclusion: Robot-assisted THA can obtain accurate placement of the acetabular cup, but there is a large deviation between the anteversion angle of the acetabular cup in the lateral position during operation and the supine position after operation. Further study is needed to define the intraoperative placement position of the acetabular cup.