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Accurate photovoltaic （PV） output power forecasting plays a crucial role in ensuring the secure and stable operation of distribution networks. In light of this， the paper proposes a short-term PV power forecasting method using cosine similarity and a hybrid TSO （tuna swarm optimization） and BP （back propagation） neural network. Firstly， the cosine similarity algorithm is utilized to identify historical data with strong resemblance to the forecast day as training samples. Subsequently， the TSO algorithm is employed to search for optimal initial weights and thresholds for the BP neural network. The TSO-BP model is then trained for short-term PV power forecasting. Finally， the TSO-BP model is applied to predict PV output power under both stable and fluctuating weather conditions. Simulation results indicate that， the proposed method， compared to traditional forecasting methods， achieves higher accuracy in predictions for both steady and fluctuating weather scenarios.

To explore the influence of raw materials from different cultivars on the quality of Sichuan dark tea, the raw materials of 4 tea cultivars were used in this study. The main chemicals and aroma components were analyzed by sensory evaluation, chemical analysis and gas chromato graphy-mass spectrometry (GC-MS) . The main components of Sichuan dark teas made from different tea cultivars were significantly different. The contents of water extract, tea polyphenols, catechins and caffeine of Sichuan dark teas from 'Zijuan' were the highest, which were 49.45%, 18.54%, 4.77%, and 4.21%, respectively, followed by Sichuan dark tea processed with 'Huangjinya' cultivar, all of them were significantly (P<0.05) higher than the Sichuan dark tea processed with 'Fuding Dabai' and 'Baiye 1'. The contents of L-asparagine, L-theanine, aspartic acid and glutamic acid were the highest of Sichuan dark teas from 'Huangjinya', which were 115.78, 279.86, 154.47, 70.76 mg/100 g, respectively, significantly (P<0.05) higher than Sichuan dark tea processed with other cultivars. Aroma analysis showed that main aroma components were alcohols, aldehydes, ketones, hydrocarbons and esters, accounting for more than 80% of the total aroma. The similarity rate of aroma between 'Fuding Dabai' and 'Baiye 1' was 0.98, and that of 'Huangjinya' and 'Zijuan' was 0.99. The Sichuan dark tea processed with the 'Baiye 1' had floral fragrance, and the Sichuan dark tea processed with the 'Zijuan' had ''stale flavor''. Sensory quality analysis showed that the comprehensive qualities of Sichuan dark teas from 'Fuding Dabai','Baiye 1' and 'Huangjinya' were the better, with a score of more than 82, while the Sichuan dark tea from 'Zijuan' had the lowest score. The Sichuan dark tea processed with 'Huangjinya' materials was rich in substances and had good comprehensive quality. The Sichuan dark tea processed with 'Baiye 1' material had floral fragrance, which could be used as a variety for processing advanced special Sichuan dark tea. The Sichuan dark tea processed with 'Zijuan' materials had high content of water extracts and tea polyphenols, with ''stale flavor''. It was suitable for blending and processing with other cultivars of low polyphenol content, and could be used as a blending variety for dark tea products with ''stale flavor''. [ABSTRACT FROM AUTHOR]

The rich impulsive noise in the power line channel poses a huge challenge to the design of MIMO-OFDM transceiver. To solve this problem, a design scheme that can jointly estimate the channel and impulsive noise was proposed, which exploited the parametric sparsity of the classical multipath model and the sparsity of the time domain impulsive noise. In this scheme, the unknown channel model parameters and the impulsive noise were jointly regarded as a sparse vector. By observing the spatial correlation of MIMO system, a compressed sensing model based on multiple measurement vectors was constructed. The multiple response sparse Bayesian learning theory was introduced to jointly estimate the MIMO channel parameters and impulsive noise. The simulation results show that, compared with the traditional receiver scheme that considers MIMO channel estimation and impulsive noise suppression separately, the receiver proposed has a significant improvement in channel estimation performance and bit error rate performance. [ABSTRACT FROM AUTHOR]

Objective: To explore the effectiveness of arthroscopic binding fixation using suture through single bone tunnel for posterior cruciate ligament (PCL) tibial insertion fractures in adults., Methods: Between October 2019 and October 2021, 16 patients with PCL tibial insertion fractures were treated with arthroscopic binding fixation using suture through single bone tunnel. There were 11 males and 5 females with an average age of 41.1 years (range, 26-58 years). The fractures were caused by traffic accident in 12 cases and sports in 4 cases. The time from injury to operation ranged from 2 to 10 days with an average of 6.0 days. The fractures were classified as Meyers-McKeever type Ⅱ in 4 cases and type Ⅲ in 9 cases, and Zaricznyi type Ⅳ in 3 cases. There were 2 cases of grade Ⅰ, 7 cases of grade Ⅱ, and 7 cases of grade Ⅲ in the posterior drawer test. There were 3 cases combined with lateral collateral ligament injury and 2 cases with meniscus injury. The visual analogue scale (VAS) score, Lysholm score, International Knee Documentation Committee (IKDC) score, and knee range of motion were used to evaluate knee joint function. The posterior drawer test and knee stability tester (Kneelax 3) were used to evaluate knee joint stability. The X-ray films were used to evaluate fracture reduction and healing., Results: All incisions healed by first intention after operation. There was no incision infection, popliteal neurovascular injury, or deep venous thrombosis of lower limbs. All patients were followed up 6-12 months, with an average of 10 months. X-ray films at 6 months after operation showed the fractures obtained bone union. There were 11 cases of grade 0, 4 cases of gradeⅠ, and 1 case of grade Ⅱin posterior drawer test, showing significant difference when compared with preoperative results ( Z =23.167, P< 0.001). The VAS score, Lysholm score, IKDC score, knee range of motion, and the results of Kneelax3 examination all significantly improved when compared with preoperative results ( P <0.05)., Conclusion: For adult patients with PCL tibial insertion fractures, the arthroscopic binding fixation using suture through single bone tunnel has the advantages of minimal trauma, good fracture reduction, reliable fixation, and fewer complications. The patient's knee joint function recovers well.

Objective: To explore the effectiveness of high strength suture fixation in treatment of patellar transverse fracture., Methods: Between June 2014 and June 2016, 38 patients with the patellar transverse fracture were treated with high strength suture internal fixation. There were 24 males and 14 females with the age of 26 to 64 years (mean, 45 years). There were 6 cases of accident injury and 32 cases of crashing injury. The time interval between injury and surgery was 2-8 days (mean, 5 days). The preoperative visual analogue scale (VAS) score, Lysholm score, and range of motion (ROM) of patients were 84.3±8.4, 44.5±7.2, and (62±12)°, respectively., Results: All patients' incisions healed by first intention after operation. There was no neurovascular injury, deep venous thrombosis of lower limbs, or local foreign matter irritation reaction. The X-ray films showed that the reduction of patella and the location of internal fixator were good at 2 days after operation. All the 38 patients were followed up 12-18 months (mean, 16 months). All fractures healed and the healing time was 2-4 months (mean, 3 months). At last follow-up, according to the Böstman criteria, 36 patients were rated as excellent and 2 as good, with an excellent and good rate of 100%. The VAS score, Lysholm score, and ROM of patients were 10.2±6.6, 93.1±6.4, and (124±14)°, respectively, showing significant differences when compared with preoperative ones ( t =42.759, P =0.000; t =31.099, P =0.000; t =20.727, P =0.000)., Conclusion: Application of high strength suture fixation in the treatment of patellar transverse fracture has advantages of simple to operate, effective fixation, and less complication. It can avoid reoperation of removing the internal fixators. The satisfied ROM and function of the knee joint can be obtained after operation.

Objective: To investigate the short-term effectiveness of joint distraction by Ilizarov combined with arthroscopic debridement in the treatment of knee osteoarthritis (KOA)., Methods: Between January 2014 and January 2015, 15 patients (15 knees) with KOA were treated using arthroscopic debridement assisting with the Ilizarov distraction technology. There were 7 males and 8 females, aged from 45 to 64 years (mean, 55 years). The left knee and the right knee were involved in 6 and 9 cases respectively. The disease duration was 2.0-9.5 years (median, 6 years). They all had received conservative treatment for 6 months and got poor clinical improvement. The preoperative visual analogue scale (VAS) score, the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score, the knee injury and osteoarthritis outcome score (KOOS), the range of motion (ROM) for knee, and the radiographic joint space width were 76.2±8.8, 59.3±5.7, 44.3±7.2, (75±21)°, and (2.5±0.4) mm respectively. According to Kellgren-Lawrence grade system, 11 cases were rated as grade III and 4 cases as grade IV., Results: There was no poor incision healing, infection, and deep vein thrombosis. All the 15 patients were followed up 12-18 months (mean, 15.5 months). Patients achieved pain relief. The knee activity was obviously improved. The postoperative VAS score, WOMAC score, KOOS score, and ROM at 12 months were 20.9±7.8, 38.2±5.5, 92.1±6.9, and (118±14)° respectively, showing significant difference when compared with preoperative ones ( t =18.213, P =0.000; t =10.317, P =0.000; t =18.564, P =0.000; t =6.599, P =0.000). Postoperative X-ray film showed that joint space width at 12 months was (3.8±0.3) mm, showing significant difference when compared with preoperative one ( t =10.070, P =0.000)., Conclusion: Joint distraction by Ilizarov combined with arthroscopic debridement can effectively relieve pain, improve the function and quality of life. It was beneficial to cartilaginous tissue repair and delaying the degenerative process of KOA. The short-term effectiveness is satisfactory.

Objective: To investigate the effect of platelet-rich plasma (PRP) gel in total knee arthroplasty., Methods: From January 2011 to January 2013, 30 patients of total knee arthroplasty were received PRP (PRP group) and 30 patients won't received PRP(normal saline group).Routine drainage and functional exercise were applied to the two groups after operation. Postoperative drainage volume, inflammatory reaction, grade of wound healed, Hospital for Special Surgery (HSS) Score for knee, the Feller Score for patella and range of motion (ROM) for knee were evaluated.Independent samples t-test, grade data used rank sum test were used to compared two groups., Results: Postoperative drainage volume was (152 ± 22) ml in PRP group and (432 ± 35) ml in normal saline group. Postoperative drainage volume were statistically significant difference between two groups (t = 37.098, P < 0.05). At 4 days after operation, no inflammatory reaction was observed in 27 cases of PRP group and in 24 cases of normal saline group, mid inflammatory reaction in 2 cases of PRP group and in 4 cases of normal saline group, moderate inflammatory reaction in 1 cases of PRP group and in 2 cases of normal saline group.Wound healed by first intention in 30 patients of PRP group and in 29 patients of normal saline group (29/30), by second intention after 3 days of dressing change in 1 patient of normal saline group using 75% alcohol wet compressed. The adverse reaction rate was 3.3%. The average follow-up period was 16 months, ranging from 10 to 24 months. Three months postoperative HSS score for knee, scores of patellar, scores of anterior knee pain and ROM for knee were statistically significant difference in PRP group and normal saline group (t = 2.288, 2.097, 2.630, 2.104; all P < 0.05). Inflammatory reaction, grade of wound healed, final follow-up HSS score for knee, scores of patellar, scores of anterior knee pain and ROM for knee had no statistically significant difference between PRP group and normal saline group (P > 0.05)., Conclusions: Using PRP gel in total knee arthroplasty can reduce postoperative drainage volume, accelerate the healing of operation incision with no extra complications.It has good short-term clinical effect.

Objective: To investigate the short-term effectiveness of reconstructive locked plate for treating sternoclavicular joint dislocation., Methods: Between February 2008 and February 2012, 11 patients with sternoclavicular joint dislocation were treated with reconstructive locked plate, and the clinical data were retrospectively analyzed. There were 7 males and 4 females, aged 30-55 years (mean, 44 years). The causes of injury included traffic accident in 8 cases and crashing in 3 cases. The disease duration ranged from 2 hours to 11 days (median, 6 days). All patients had anterior dislocation of sternoclavicular joint. According to the Grade system, there were 2 cases of type II and 9 cases of type III., Results: All patients obtained healing of incisions by first intention after operation. There was no neurovascular injury. The X-ray films showed that satisfactory reduction of joint dislocation and stable internal fixation were obtained at 2 days after operation. All patients were followed up 9-24 months (mean, 16 months). According to the Rockwood criteria, the score was 10-15 (mean, 13.2); the results were excellent in 9 cases and good in 2 cases, with an excellent and good rate of 100% at 9 months after operation. No internal fixation failure or re-dislocation occurred. All internal fixators were removed at 9-15 months after operation. Both the stability and the functions of the shoulder joint were good., Conclusion: The reconstructive locked plate in treating sternoclavicular joint dislocation has the advantages of good stability and satisfactory reduction, and the patients can do functional exercises early and obtain good recovery of the shoulder joint function. The short-term effectiveness is satisfactory.

Objective: To explore the effectivness of arthroscopic synovectomy in the treatment of pigmented villonodular synovitis (PVNS) of the knee., Methods: A retrospective analysis was conducted on 13 patients with PVNS of the knee treated with arthroscopic synovectomy between June 2008 and December 2011, including 8 left knees and 5 right knees. There were 9 males and 4 females, aged 25-45 years (mean, 33 years). Of 13 patients, 5 had a history of trauma, and 8 had no history of trauma. The disease duration ranged from 4 months to 80 months (mean, 44 months). The preoperative Lysholm score was 45.3 +/- 4.2, and International Knee Documentation Committee (IKDC) 2000 score was 46.8 +/- 4.9. All patients underwent arthroscopic synovectomy and postoperative radiotherapy., Results: The pathological examination proved PVNS in all cases. All incisions obtained healing by first intention after operation. There was no neurovascular injury or knee infection. The average follow-up period was 21.8 months (range, 12-30 months). The Lysholm score was 90.2 +/- 7.4, and IKDC2000 score was 87.8 +/- 3.8 at last follow-up, showing significant differences when compared with preoperative scores (t = 22.64, P = 0.00; t = 24.32, P = 0.00). No recurrence was observed during follow-up., Conclusion: Arthroscopic synovectomy can be effective in the treatment of PVNS of the knee, and it has the merits of minimal invasion, rapid function recovery of the knee joint, and satisfactory results. So it is a safe, promising, and minimal invasive procedure in treatment of PVNS.