During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow...During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.展开更多
Background: Elbow dislocations in pediatric patients are rare injuries. This is a therapeutic emergency because a delay in treatment can have disastrous consequences on the functional level of the upper limb. Objectiv...Background: Elbow dislocations in pediatric patients are rare injuries. This is a therapeutic emergency because a delay in treatment can have disastrous consequences on the functional level of the upper limb. Objective: To present the management of elbow dislocation in children in cases of limited resources. Presentation of the Cases: These were 2 older male children aged 7 and 9 years old, admitted to the emergency room for painful functional impotence of the right elbow after a fall and landing on the right hand. Clinical and radiological examinations were in favor of posterior elbow dislocations. The reductions were carried out under sedation and immobilization in Jersey. According to Robert’s criteria, the functional result was excellent in both patients. Conclusion: Emergency reduction and immobilization whatever the means ensure an excellent functional prognosis even in cases of limited resources.展开更多
BACKGROUND In recent years,the use of Magnesium alloy implants have gained renewed popularity,especially after the first commercially available ConformitéEuropéenne approved Magnesium implant became availabl...BACKGROUND In recent years,the use of Magnesium alloy implants have gained renewed popularity,especially after the first commercially available ConformitéEuropéenne approved Magnesium implant became available(MAGNEZIX®CS,Syntellix)in 2013.AIM To document our clinical and radiographical outcomes using magnesium implants in treating peri-articular elbow fractures.METHODS Our paper was based on a retrospective case series design.Intra-operatively,a standardized surgical technique was utilized for insertion of the magnesium implants.Post–operatively,clinic visits were standardized and physical exam findings,functional scores,and radiographs were obtained at each visit.All complications were recorded.RESULTS Five patients with 6 fractures were recruited(2 coronoid,3 radial head and 1 capitellum).The mean patient age and length of follow up was 54.6 years and 11 months respectively.All fractures healed,and none exhibited loss of reduction or complications requiring revision surgery.No patient developed synovitis of the elbow joint or suffered electrolytic reactions when titanium implants were used concurrently.CONCLUSION Although there is still a paucity of literature available on the subject and further studies are required,magnesium implants appear to be a feasible tool for fixation of peri-articular elbow fractures with promising results in our series.INTRODUCTION In recent years,the use of Magnesium alloy implants in orthopaedic surgeries have gained renewed popularity.Apart from being bioabsorbable,negating the need for implant removal,magnesium also has good osteoconductive properties[1-4].Biomechanically,it exhibits greater biomechanical strength than any pre-existing polymers,and reduces the stress-shielding effect associated with titanium and steel implants as it has a Young’s modulus closer to bone[4].Currently,the main utility of magnesium implants in the orthopaedic community is within the foot and ankle community where satisfactory results have been reported with its utility in forefoot osteotomies[5-7].However,its utility in the setting of orthopaedic trauma has been steadily increasing[8].Our study aims to document our clinical and radiographical outcomes using magnesium implants to treat peri-articular elbow fractures.To our knowledge,our study is the first study analyzing outcomes in radial head and coronoid fractures in the English literature.展开更多
BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate ...BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate magnetic resonance imaging(MRI)multisequence imaging for improving the diagnostic accuracy of adult elbow cartilage injury.METHODS A total of 60 patients diagnosed with elbow cartilage injury in our hospital from January 2020 to December 2021 were enrolled in this retrospective study.We analyzed the accuracy of conventional MRI sequences(T1-weighted imaging,T2-weighted imaging,proton density weighted imaging,and T2 star weighted image)and Three-Dimensional Coronary Imaging by Spiral Scanning(3D-CISS)in the diagnosis of elbow cartilage injury.Arthroscopy was used as the gold standard to evaluate the diagnostic effect of single and combination sequences in different injury degrees and the consistency with arthroscopy.RESULTS The diagnostic accuracy of 3D-CISS sequence was 89.34%±4.98%,the sensitivity was 90%,and the specificity was 88.33%,which showed the best performance among all sequences(P<0.05).The combined application of the whole sequence had the highest accuracy in all sequence combinations,the accuracy of mild injury was 91.30%,the accuracy of moderate injury was 96.15%,and the accuracy of severe injury was 93.33%(P<0.05).Compared with arthroscopy,the combination of all MRI sequences had the highest consistency of 91.67%,and the kappa value reached 0.890(P<0.001).CONCLUSION Combination of 3D-CISS and each sequence had significant advantages in improving MRI diagnostic accuracy of elbow cartilage injuries in adults.Multisequence MRI is recommended to ensure the best diagnosis and treatment.展开更多
Introduction: The elbow is a superficial joint, particularly exposed to direct impact, forced movement, and overstrain. Our work aimed to study magnetic resonance imaging (MRI) pathologies of the soft tissues of the e...Introduction: The elbow is a superficial joint, particularly exposed to direct impact, forced movement, and overstrain. Our work aimed to study magnetic resonance imaging (MRI) pathologies of the soft tissues of the elbow through illustrative cases. Methodology: This was a retrospective and prospective cross-sectional study covering a period of one year, from June 2020 to June 2021, at the Saint Camille Hospital in Ouagadougou and the Polyclinique Notre Dame de la Paix. Results: In general, this study found that the pathologies diagnosed on MRI were lateral epicondylitis, subcutaneous type V elbow lipoma and liposarcoma, anteromedial cortical fracture of the radial cup, cortical detachment fracture of the lateral epicondylitis, medial epicondylitis, villonodular articular synovitis, simple dermo-hypodermatitis, sequellar fibrosis of the ulnar nerve, Workman's syndrome (median and ulnar nerves) and osteoarthritis of the elbow. Lateral epicondylitis was the most frequent pathology, and most patients consulted for elbow pain predominantly associated with pressure on the epicondyle, with relative functional impotence and, occasionally, elbow swelling. Conclusion: MRI, as a complement to ultrasound and radiography, remains the most informative examination for exploring soft-tissue pathologies of the elbow.展开更多
This study was conducted to investigate the flow field characteristics of right-angled flow passage with various cavities in the typical hydraulic manifold block.A low-speed visualization test rig was developed and th...This study was conducted to investigate the flow field characteristics of right-angled flow passage with various cavities in the typical hydraulic manifold block.A low-speed visualization test rig was developed and the flow field of the right-angled flow passage with different cavity structures was measured using 2D-PIV technique.Numerical model was established to simulate the three-dimensional flow field.Seven eddy viscosity turbulence models were investigated in predicting the flow field by comparing against the particle image relocimetry(PIV)measurement results.By defining the weight error function K,the S-A model was selected as the appropriate turbulence model.Then,a three-factor,three-level response surface numerical test was conducted to investigate the influence of flow passage connection type,cavity diameter and cavity length-diameter ratio on pressure loss.The results show that the Box-Benhnken Design(BBD)model can predict the total pressure loss accurately.The optimal factor level appeared in flow passage connection type II,14.64 mm diameter and 67.53%cavity length-diameter ratio.The total pressure loss decreased by 11.15%relative to the worst factor level,and total pressure loss can be reduced by 64.75%when using an arc transition right-angled flow passage,which indicates a new direction for the optimization design of flow passage in hydraulic manifold blocks.展开更多
The problem of scattering of SH-wave by a circular cavity and an arbitrary beeline crack in right-angle plane was investigated using the methods of Green's function,complex variables and muti-polar coordinates.Fir...The problem of scattering of SH-wave by a circular cavity and an arbitrary beeline crack in right-angle plane was investigated using the methods of Green's function,complex variables and muti-polar coordinates.Firstly,we constructed a suitable Green's function,which is an essential solution to the displacement field for the elastic right-angle plane possessing a circular cavity while bearing out-of-plane harmonic line source load at arbitrary point.Secondly,based on the method of crack-division,integration for solution was established,then expressions of displacement and stress were obtained while crack and circular cavities were both in existence.Finally,the dynamic stress concentration factor around the circular cavity and the dynamic stress intensity factor at crack tip were discussed to the cases of different parameters in numerical examples.Calculation results show that the crack produces adverse engineering influence on both of the dynamic stress concentration factor and the dynamic stress intensity factor.展开更多
Complex function method and multi-polar coordinate transformation technology are used here to study scattering of circular cavity in right-angle planar space to SH-wave with out-of-plane loading on the horizontal stra...Complex function method and multi-polar coordinate transformation technology are used here to study scattering of circular cavity in right-angle planar space to SH-wave with out-of-plane loading on the horizontal straight boundary. At first, Green function of right-angle planar space which has no circular cavity is constructed; then the scattering solution which satisfies the free stress conditions of the two right-angle boundaries with the circular cavity existing in the space is formulated. Therefore, the total displacement field can be constructed using overlapping principle. An infinite algebraic equations of unknown coefficients existing in the scattering solution field can be gained using multi-polar coordinate and the free stress condition at the boundary of the circular cavity. It can be solved by using limit items in the infinite series which can give a high computation precision. An example is given to illustrate the variations of the tangential stress at the boundary of the circular cavity due to different dimensionless wave numbers, the location of the circular cavity, the loading center and the distributing range of the out-of-plane loading. The results show the efficiency and effectiveness of the mothod introduced here.展开更多
Groins are employed to prevent nearshore areas from erosion and to control the direction of flow. However, the groin structure and its associated flow characteristics are the main causes of local erosion. In this stud...Groins are employed to prevent nearshore areas from erosion and to control the direction of flow. However, the groin structure and its associated flow characteristics are the main causes of local erosion. In this study, we investigate the flow patterns around refractive and right-angle groins. In particular, we analytically compare the flow characteristics around a refractive groin and study the degree of accuracy that can be achieved by using a right-angle groin of various projected lengths. To compare the flow characteristics, we replaced the right-angle groin with an approximation of a refractive groin. This replacement had the least effect on the maximum velocity of flow in the channel. Moreover, we investigated the distribution of the density variables of temperature and salinity, and their effects on the flow characteristics around the right-angle groin. A comparison of the flow analysis results in baroclinic and barotropic conditions reveals that the flow characteristic values are very similar for both the refractive and right-angle groins. The geometry of the groin, i.e., right-angle or refractive, has little effect on the maximum speed to relative average speed. Apart from the angular separation, the arm length of the groin in downstream refractive groins has less effect on other flow characteristics than do upstream refractive groins. We also correlated a number of non-dimensional variables with respect to various flow characteristics and groin geometry. These comparisons indicate that the correlation between the thalweg height and width of the channel and groin arm's length to projection length have been approximated using linear and nonlinear formulas regardless of inner velocity in the subcritical flow.展开更多
k-means is a popular clustering algorithm because of its simplicity and scalability to handle large datasets.However,one of its setbacks is the challenge of identifying the correct k-hyperparameter value.Tuning this v...k-means is a popular clustering algorithm because of its simplicity and scalability to handle large datasets.However,one of its setbacks is the challenge of identifying the correct k-hyperparameter value.Tuning this value correctly is critical for building effective k-means models.The use of the traditional elbow method to help identify this value has a long-standing literature.However,when using this method with certain datasets,smooth curves may appear,making it challenging to identify the k-value due to its unclear nature.On the other hand,various internal validation indexes,which are proposed as a solution to this issue,may be inconsistent.Although various techniques for solving smooth elbow challenges exist,k-hyperparameter tuning in high-dimensional spaces still remains intractable and an open research issue.In this paper,we have first reviewed the existing techniques for solving smooth elbow challenges.The identified research gaps are then utilized in the development of the new technique.The new technique,referred to as the ensemble-based technique of a self-adapting autoencoder and internal validation indexes,is then validated in high-dimensional space clustering.The optimal k-value,tuned by this technique using a voting scheme,is a trade-off between the number of clusters visualized in the autoencoder’s latent space,k-value from the ensemble internal validation index score and one that generates a value of 0 or close to 0 on the derivative f″′(k)(1+f′(k)^(2))−3 f″(k)^(2)f″((k)2f′(k),at the elbow.Experimental results based on the Cochran’s Q test,ANOVA,and McNemar’s score indicate a relatively good performance of the newly developed technique in k-hyperparameter tuning.展开更多
BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED ma...BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED managed secondarily with open reduction and soft tissue repair following failure of closed reduction.CASE SUMMARY A 67-year-old woman suffered SLED after falling on her outstretched left hand with her elbow extended.She developed pain,swelling,and movement restriction in the elbow;there were no neurovascular symptoms,except for numbness in the 4th and 5th digits.Radiologic investigation confirmed the SLED,and a closed reduction under anesthesia was performed.The follow-up radiographs at 1-wk revealed failure of reduction;accordingly,open reduction with lateral collateral ligament and common extensor origin repair were carried out.The patient regained full elbow range of motion by six weeks.CONCLUSION Adequate concentric reduction for SLED,conservatively or surgically,reduces complications and provides a more functional joint.展开更多
基金supported by the Petrochina's “14th Five-Year plan” Project(2021DJ2804)Sichuan Natural Science Foundation(2023NSFSC0422)。
文摘During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.
文摘Background: Elbow dislocations in pediatric patients are rare injuries. This is a therapeutic emergency because a delay in treatment can have disastrous consequences on the functional level of the upper limb. Objective: To present the management of elbow dislocation in children in cases of limited resources. Presentation of the Cases: These were 2 older male children aged 7 and 9 years old, admitted to the emergency room for painful functional impotence of the right elbow after a fall and landing on the right hand. Clinical and radiological examinations were in favor of posterior elbow dislocations. The reductions were carried out under sedation and immobilization in Jersey. According to Robert’s criteria, the functional result was excellent in both patients. Conclusion: Emergency reduction and immobilization whatever the means ensure an excellent functional prognosis even in cases of limited resources.
文摘BACKGROUND In recent years,the use of Magnesium alloy implants have gained renewed popularity,especially after the first commercially available ConformitéEuropéenne approved Magnesium implant became available(MAGNEZIX®CS,Syntellix)in 2013.AIM To document our clinical and radiographical outcomes using magnesium implants in treating peri-articular elbow fractures.METHODS Our paper was based on a retrospective case series design.Intra-operatively,a standardized surgical technique was utilized for insertion of the magnesium implants.Post–operatively,clinic visits were standardized and physical exam findings,functional scores,and radiographs were obtained at each visit.All complications were recorded.RESULTS Five patients with 6 fractures were recruited(2 coronoid,3 radial head and 1 capitellum).The mean patient age and length of follow up was 54.6 years and 11 months respectively.All fractures healed,and none exhibited loss of reduction or complications requiring revision surgery.No patient developed synovitis of the elbow joint or suffered electrolytic reactions when titanium implants were used concurrently.CONCLUSION Although there is still a paucity of literature available on the subject and further studies are required,magnesium implants appear to be a feasible tool for fixation of peri-articular elbow fractures with promising results in our series.INTRODUCTION In recent years,the use of Magnesium alloy implants in orthopaedic surgeries have gained renewed popularity.Apart from being bioabsorbable,negating the need for implant removal,magnesium also has good osteoconductive properties[1-4].Biomechanically,it exhibits greater biomechanical strength than any pre-existing polymers,and reduces the stress-shielding effect associated with titanium and steel implants as it has a Young’s modulus closer to bone[4].Currently,the main utility of magnesium implants in the orthopaedic community is within the foot and ankle community where satisfactory results have been reported with its utility in forefoot osteotomies[5-7].However,its utility in the setting of orthopaedic trauma has been steadily increasing[8].Our study aims to document our clinical and radiographical outcomes using magnesium implants to treat peri-articular elbow fractures.To our knowledge,our study is the first study analyzing outcomes in radial head and coronoid fractures in the English literature.
文摘BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate magnetic resonance imaging(MRI)multisequence imaging for improving the diagnostic accuracy of adult elbow cartilage injury.METHODS A total of 60 patients diagnosed with elbow cartilage injury in our hospital from January 2020 to December 2021 were enrolled in this retrospective study.We analyzed the accuracy of conventional MRI sequences(T1-weighted imaging,T2-weighted imaging,proton density weighted imaging,and T2 star weighted image)and Three-Dimensional Coronary Imaging by Spiral Scanning(3D-CISS)in the diagnosis of elbow cartilage injury.Arthroscopy was used as the gold standard to evaluate the diagnostic effect of single and combination sequences in different injury degrees and the consistency with arthroscopy.RESULTS The diagnostic accuracy of 3D-CISS sequence was 89.34%±4.98%,the sensitivity was 90%,and the specificity was 88.33%,which showed the best performance among all sequences(P<0.05).The combined application of the whole sequence had the highest accuracy in all sequence combinations,the accuracy of mild injury was 91.30%,the accuracy of moderate injury was 96.15%,and the accuracy of severe injury was 93.33%(P<0.05).Compared with arthroscopy,the combination of all MRI sequences had the highest consistency of 91.67%,and the kappa value reached 0.890(P<0.001).CONCLUSION Combination of 3D-CISS and each sequence had significant advantages in improving MRI diagnostic accuracy of elbow cartilage injuries in adults.Multisequence MRI is recommended to ensure the best diagnosis and treatment.
文摘Introduction: The elbow is a superficial joint, particularly exposed to direct impact, forced movement, and overstrain. Our work aimed to study magnetic resonance imaging (MRI) pathologies of the soft tissues of the elbow through illustrative cases. Methodology: This was a retrospective and prospective cross-sectional study covering a period of one year, from June 2020 to June 2021, at the Saint Camille Hospital in Ouagadougou and the Polyclinique Notre Dame de la Paix. Results: In general, this study found that the pathologies diagnosed on MRI were lateral epicondylitis, subcutaneous type V elbow lipoma and liposarcoma, anteromedial cortical fracture of the radial cup, cortical detachment fracture of the lateral epicondylitis, medial epicondylitis, villonodular articular synovitis, simple dermo-hypodermatitis, sequellar fibrosis of the ulnar nerve, Workman's syndrome (median and ulnar nerves) and osteoarthritis of the elbow. Lateral epicondylitis was the most frequent pathology, and most patients consulted for elbow pain predominantly associated with pressure on the epicondyle, with relative functional impotence and, occasionally, elbow swelling. Conclusion: MRI, as a complement to ultrasound and radiography, remains the most informative examination for exploring soft-tissue pathologies of the elbow.
基金Projects(51705446,51890881) supported by the National Natural Science Foundation of China
文摘This study was conducted to investigate the flow field characteristics of right-angled flow passage with various cavities in the typical hydraulic manifold block.A low-speed visualization test rig was developed and the flow field of the right-angled flow passage with different cavity structures was measured using 2D-PIV technique.Numerical model was established to simulate the three-dimensional flow field.Seven eddy viscosity turbulence models were investigated in predicting the flow field by comparing against the particle image relocimetry(PIV)measurement results.By defining the weight error function K,the S-A model was selected as the appropriate turbulence model.Then,a three-factor,three-level response surface numerical test was conducted to investigate the influence of flow passage connection type,cavity diameter and cavity length-diameter ratio on pressure loss.The results show that the Box-Benhnken Design(BBD)model can predict the total pressure loss accurately.The optimal factor level appeared in flow passage connection type II,14.64 mm diameter and 67.53%cavity length-diameter ratio.The total pressure loss decreased by 11.15%relative to the worst factor level,and total pressure loss can be reduced by 64.75%when using an arc transition right-angled flow passage,which indicates a new direction for the optimization design of flow passage in hydraulic manifold blocks.
文摘The problem of scattering of SH-wave by a circular cavity and an arbitrary beeline crack in right-angle plane was investigated using the methods of Green's function,complex variables and muti-polar coordinates.Firstly,we constructed a suitable Green's function,which is an essential solution to the displacement field for the elastic right-angle plane possessing a circular cavity while bearing out-of-plane harmonic line source load at arbitrary point.Secondly,based on the method of crack-division,integration for solution was established,then expressions of displacement and stress were obtained while crack and circular cavities were both in existence.Finally,the dynamic stress concentration factor around the circular cavity and the dynamic stress intensity factor at crack tip were discussed to the cases of different parameters in numerical examples.Calculation results show that the crack produces adverse engineering influence on both of the dynamic stress concentration factor and the dynamic stress intensity factor.
文摘Complex function method and multi-polar coordinate transformation technology are used here to study scattering of circular cavity in right-angle planar space to SH-wave with out-of-plane loading on the horizontal straight boundary. At first, Green function of right-angle planar space which has no circular cavity is constructed; then the scattering solution which satisfies the free stress conditions of the two right-angle boundaries with the circular cavity existing in the space is formulated. Therefore, the total displacement field can be constructed using overlapping principle. An infinite algebraic equations of unknown coefficients existing in the scattering solution field can be gained using multi-polar coordinate and the free stress condition at the boundary of the circular cavity. It can be solved by using limit items in the infinite series which can give a high computation precision. An example is given to illustrate the variations of the tangential stress at the boundary of the circular cavity due to different dimensionless wave numbers, the location of the circular cavity, the loading center and the distributing range of the out-of-plane loading. The results show the efficiency and effectiveness of the mothod introduced here.
文摘Groins are employed to prevent nearshore areas from erosion and to control the direction of flow. However, the groin structure and its associated flow characteristics are the main causes of local erosion. In this study, we investigate the flow patterns around refractive and right-angle groins. In particular, we analytically compare the flow characteristics around a refractive groin and study the degree of accuracy that can be achieved by using a right-angle groin of various projected lengths. To compare the flow characteristics, we replaced the right-angle groin with an approximation of a refractive groin. This replacement had the least effect on the maximum velocity of flow in the channel. Moreover, we investigated the distribution of the density variables of temperature and salinity, and their effects on the flow characteristics around the right-angle groin. A comparison of the flow analysis results in baroclinic and barotropic conditions reveals that the flow characteristic values are very similar for both the refractive and right-angle groins. The geometry of the groin, i.e., right-angle or refractive, has little effect on the maximum speed to relative average speed. Apart from the angular separation, the arm length of the groin in downstream refractive groins has less effect on other flow characteristics than do upstream refractive groins. We also correlated a number of non-dimensional variables with respect to various flow characteristics and groin geometry. These comparisons indicate that the correlation between the thalweg height and width of the channel and groin arm's length to projection length have been approximated using linear and nonlinear formulas regardless of inner velocity in the subcritical flow.
文摘k-means is a popular clustering algorithm because of its simplicity and scalability to handle large datasets.However,one of its setbacks is the challenge of identifying the correct k-hyperparameter value.Tuning this value correctly is critical for building effective k-means models.The use of the traditional elbow method to help identify this value has a long-standing literature.However,when using this method with certain datasets,smooth curves may appear,making it challenging to identify the k-value due to its unclear nature.On the other hand,various internal validation indexes,which are proposed as a solution to this issue,may be inconsistent.Although various techniques for solving smooth elbow challenges exist,k-hyperparameter tuning in high-dimensional spaces still remains intractable and an open research issue.In this paper,we have first reviewed the existing techniques for solving smooth elbow challenges.The identified research gaps are then utilized in the development of the new technique.The new technique,referred to as the ensemble-based technique of a self-adapting autoencoder and internal validation indexes,is then validated in high-dimensional space clustering.The optimal k-value,tuned by this technique using a voting scheme,is a trade-off between the number of clusters visualized in the autoencoder’s latent space,k-value from the ensemble internal validation index score and one that generates a value of 0 or close to 0 on the derivative f″′(k)(1+f′(k)^(2))−3 f″(k)^(2)f″((k)2f′(k),at the elbow.Experimental results based on the Cochran’s Q test,ANOVA,and McNemar’s score indicate a relatively good performance of the newly developed technique in k-hyperparameter tuning.
文摘BACKGROUND Simple lateral elbow dislocation(SLED)is a rare type of elbow dislocation;however,its treatment may be complicated by accompanying soft tissue or neurovascular damage.Herein,we report a rare case of SLED managed secondarily with open reduction and soft tissue repair following failure of closed reduction.CASE SUMMARY A 67-year-old woman suffered SLED after falling on her outstretched left hand with her elbow extended.She developed pain,swelling,and movement restriction in the elbow;there were no neurovascular symptoms,except for numbness in the 4th and 5th digits.Radiologic investigation confirmed the SLED,and a closed reduction under anesthesia was performed.The follow-up radiographs at 1-wk revealed failure of reduction;accordingly,open reduction with lateral collateral ligament and common extensor origin repair were carried out.The patient regained full elbow range of motion by six weeks.CONCLUSION Adequate concentric reduction for SLED,conservatively or surgically,reduces complications and provides a more functional joint.