Key Points Of Operation Research Articles

Chinese expert consensus on diagnostic vitrectomy for biopsy (2022)

For vitreous or retinal choroidal diseases of unknown origin, diagnostic vitrectomy can be performed for auxiliary diagnosis. With the development of laboratory testing technology and minimally invasive vitrectomy in recent years, diagnostic vitrectomy for biopsy has been widely used in clinical practice. To standardize the clinical application of diagnostic vitrectomy for biopsy, the Ocular Oncology Committee of China Anti-Cancer Association, Ophthalmological Society of China Medicine Education Association has organized relevant experts and developed this consensus after repeated discussions on the role of diagnostic vitrectomy for biopsy, the key points of operation, specimen delivery, test selection, and complications.

The Clinical Significance of Detecting Blood Supply to the Inferior Parathyroid Gland Based on the "Layer of Thymus-Blood Vessel-Inferior Parathyroid Gland" Concept.

Objective How to preserve the inferior parathyroid gland (IPTG) in situ during central neck dissection (CND) is the major concern of thyroid surgeons. The “layer of thymus-blood vessel-IPTG” (TBP layer) concept showed to be effective in preserving IPTG. The objective of this study was to identify the origin and course of blood supply to IPTG (IPBS) within the TBP layer and to take key points of operation during CND. Design This is a retrospective control study. Participants. Patients who underwent thyroidectomy plus CND using the TBP layer concept and conventional technique between 2017 and 2019 were enrolled. Measurements. The origin and course of IPBS in relation to recurrent laryngeal nerve (RLN) and thymus and prevalence of hypoparathyroidism were detected. Results A total of 71.3% of IPTGs (251 of 352) were supplied by ITA branches, defined as type A. Type A was further divided into Types A1 (branches of ITA, coursing laterally to the RLN (53.1%, 187 of 352)) and A2 (branches of ITA, traversing medially to the RLN (18.2%, 64 of 352)). Type A2 was more common on the right side than on the left side (P < 0.001). Fifty-five (15.6%) IPTG feeding vessels originated from the thymus or mediastinum. Nineteen (5.4%) IPTGs were supplied by branches of the superior thyroid artery. The incidence of transient hypoparathyroidism decreased from 45.7% to 3.6% (P < 0.001), in the TBP layer group compared with the conventional technique group. Conclusion The origin and course of IPBS follow a definite pattern. This mapping and precautions help surgeons optimize intraoperative manipulations for better preservation of IPBS during CND.

LIU Zhi-shun's experience in treatment of infertility with decreasing ovarian reserve with electroacupuncture

To summarize LIU Zhi-shun's clinical experience in treatment of infertility with decreasing ovarian reserve (DOR) with electroacupuncture. LIU Zhi-shun believes that the location of infertility with DOR is the uterus, mainly involving the kidney, thoroughfare and conception vessels. He advocates to select acupoints by combining "disease-symptom-position" with prescription, and selects acupoint prescription of Bushen Tiaochong Zhuyun included Guanyuan (CV 4), Zigong (EX-CA 1), Tianshu (ST 25), Sanyinjiao (SP 6), Ciliao (BL 32) and Zhongliao (BL 33) for electroacupuncture treatment. The key points of operation are accurate positioning and deep acupuncture, focusing on regulating mind and getting qi, adopting electroacupuncture treatment and low frequency stimulation and treating slowly for long-term disease.

An Experimental and Computational Investigation of Tailor-Developed Combustion and Air-Handling System Concepts in a Heavy-Duty Gasoline Compression Ignition Engine

This study investigates using tailor-developed combustion and air-handling system concepts to achieve high-efficiency, clean gasoline compression ignition (GCI) combustion, aimed at addressing a future heavy-duty ultralow NOx standard of 0.027 g/kWh at the vehicle tailpipe and the tightening CO2 limits around the world by combining GCI with a cost-effective engine aftertreatment system. The development activities were conducted based on a 15 L heavy-duty diesel engine. By taking an analysis-led design approach, a first-generation (Gen1) GCI engine concept was developed and tested, encompassing tailor-designed piston bowl geometry, fuel spray pattern, and swirl motion paired with a customized, fixed-geometry, two-stage turbocharging system and a high-pressure EGR loop with two-stage cooling. Across four key steady-state operating points, the Gen1 GCI concept demonstrated 85–95% lower smoke and 2–3% better diesel-equivalent gross indicated fuel consumption compared to the diesel baseline at 1 g/kWh engine-out NOx. By upgrading to a Gen2 air-handling concept that was composed of a prototype, single-stage, variable-geometry turbocharger and a less restrictive EGR loop, 1D system-level analysis predicted that the pumping mean effective pressure was reduced by 43–54% and the diesel-equivalent brake-specific fuel consumption was improved by 2–4%, thereby demonstrating the performance enhancement potential of refining the air-handling system.

An Improved Method for Parameter Identification and Performance Estimation of PV Modules From Manufacturer Datasheet Based On Temperature-Dependent Single-Diode Model

The single-diode model (SDM) is widely used in photovoltaic (PV) system modeling and output power estimation because of its simplicity and accuracy. This article proposed an improved and comprehensive method for parameter identification and performance estimation by using manufacturer datasheet information for PV module. The temperature dependence of all physical parameters in SDM of PV module is comprehensively considered and investigated for varying operating conditions. In the proposed method, all physical parameters under reference condition and their temperature coefficients are calculated from information in manufacturer datasheet, which can be used for parameter calculation and output power estimation under varying operating conditions. To improve the accuracy and efficiency, the analytical and optimization methods are combined in calculation procedure of parameter extraction. By using analytical derivation from I–V equations at key operating points and their temperature coefficients, it reduces the dimensions of the search space and save computational cost for parameter optimization. The accuracy and effectiveness of the proposed method are validated by massive experimental data under varying operating conditions for different type PV modules. The proposed processes are simple and especially useful to calculate the actual performances of PV modules under operating conditions, making it scalable for direct online application.

Performance of bioethanol and diesel fuel by thermodynamic simulation of the miller cycle in the diesel engine

The rapid growth in automotive industry and increased fuel consumption and environmental pollution, along with decrease in oil and fossil fuel resources, necessitate the adoption of new technologies to improve engine thermal efficiency and the use of alternative fuels. So, the present study proposes the thermodynamic cycle model of engine based on the Miller cycle and the use of bioethanol and diesel fuels. To analyze the cycle performance after examining the thermodynamic processes of the Miller cycle in the pressure diagram in terms of volume and calculating the amount of the operating fluid (fuel) and its thermodynamic properties based on bioethanol and diesel fuels and a homogeneous mixture of air, temperature was determined at the key points of engine operation through thermodynamic relationships. Then, the changes of engine performance parameters including output power and thermal efficiency were compared in terms of compression ratio based on Miller cycle using bioethanol and diesel fuels and they were also compared to the Otto cycle. The results showed that by increasing density ratio, the output power and thermal efficiency first increase and then decrease. Assuming to have the same volumetric efficiency and use bioethanol fuel, the engine output power and thermal efficiency would increase. Under optimum conditions of engine performance, power at the maximum point of efficiency and efficiency at the maximum point of power in the Miller cycle were greater than those of the Otto cycle. The results can be generalized to Atkinson cycle and other alternative fuels and used in a more practical way in the design and performance evaluation of internal combustion engines.

The Identification of an Adequate Stressing Level to Find the Proper Running-In Conditions of a Lubricated DLC-Metal-System

Using a tribometer equipped with a high-resolution wear measurement unit (RNT), the running-in of a diamondlike carbon (DLC) iron spray coating contact was analyzed and optimized. The optimization comprised an initial parameter field with different load and speed levels to find key operation points. These points were used to compose a dedicated running-in parameter field. The analysis underlined the importance of identifying the adequate stressing conditions. With respect to our concept of the running-in corridor, a high-power running-in has to be preferred to obtain a tribological system with low friction, small total wear and wear rate, high system stability, and low sensitivity to external changes.

I–V Data Operated High-Quality Photovoltaic Solution Through Per-Unit Single-Diode Model

The work presented here uses a novel photovoltaic (PV) parameter extraction method that uses the generalized per-unit single-diode model (PUSDM) of a PV module. In the first extraction stage, the PUSDM is approximated as an explicit nonlinear model (EXNLM). The EXNLM utilizes the experimental current-voltage (I-V) data of a PV module to estimate initial guesses. The second stage exploits the PUSDM with reduced parameters and extracts the three parameters using the nonlinear least-square-fit (NLLSF) technique. The third stage refines the five parameters using the original PUSDM. Here, again the NLLSF is employed using the solution obtained in the second stage as the initial guesses. The proposed method is tested on the experimental and synthetic I-V curves of several silicon PV cells and modules commonly available in the PV literature using MATLAB programming platform. The high-quality PV solution is obtained with the least computational cost ever published in the PV literature. The other salient features of the work are: 1) an ability to work without the PV module key operating points, 2) a self-computation of the initial guesses, and 3) an ability to work with the partial I-V data points. Most importantly, the MATLAB-script of the proposed method is made available for ready-use through e-mail.

Assembling Construction Technology of Prefabricated Box Culvert Components

Box culverts are common small structures in highway engineering. According to domestic and foreign practical experience in recent years, component factory prefabrication combined with on-site assembly can effectively improve production efficiency and construction quality. It will become the main trend in the box culvert structure and gradually replace the traditional cast-in-place process. Based on the project of 03A design section of Daqing to Guangzhou Expressway, this paper expounds in detail the assembly process and key operation points of prefabricated components. It also compared with the traditional culvert construction technique, which demonstrates the superiority of prefabricated box culvert assembly technology.

Economic aspects of green technologies

The article reveals the characteristics and principles of “green” technologies from an economic point of view and discusses the key points of implementation and operation of “green” technologies. The authors have analyzed the development of “green” innovations in different countries and the level of their economic development. They have considered a number of countries using innovative technologies and the process of implementing such technologies in practice in the case of water-purifying product “BINGSTI”.

Off-design performance analysis of hybridised aircraft gas turbine

ABSTRACTAn advanced geared turbofan with year 2035 technology level assumptions was established and used for the hybridisation study in this paper. By boosting the low-speed shaft of the turbofan with electrical power through the accessory gearbox, a parallel hybrid concept was set up. Focusing on the off-design performance of the hybridised gas turbine, electrical power input to the shaft, defined as positive hybridisation in this context, generally moves the compressor operation towards surge. On the other hand, the negative hybridisation, which is to reverse the power flow direction can improve the part-load operations of the turbofan and minimise the use of compressor handling bleeds. For the pre-defined mission given in the paper, negative hybridisation of descent, approach and landing, and taxi operations with 580 kW, 240 kW and 650 kW, respectively was found sufficient to keep a minimum compressor surge margin requirement without handling bleed.Looking at the hybridisation of key operating points, boosting the cruise operation of the baseline geared turbofan is, however, detrimental to the engine efficiency as it is pushing the cruise operation further away from the energy optimal design point. Without major modifications to the engine design, the benefit of the hybridisation appears primarily at the thermomechanical design point, the hot-day take-off. With the constraint of the turbine blade metal temperature in mind, a 500kW positive hybridisation at hot-day take-off gave cruise specific fuel consumption (SFC) reduction up to 0.5%, mainly because of reduced cooling flow requirement. Through the introduction of typical electrical power system performance characteristics and engine performance exchange rates, a first principles assessment is illustrated. By applying the strategies discussed in the paper, a 3% reduction in block fuel burn can be expected, if a higher power density electrical power system can be achieved.

The application of three-dimensional printing abdominal aortic aneurysm improve the teaching effect for the residents in vascular surgery department

Objective To evaluate 3D printing abdominal aortic aneurysm model in analysis of clinical teaching effect for standardized resident doctors in vascular surgery department. Methods 48 residents in vascular surgery department in our hospital from December 2016 to September 2017 were seleeected and randomly divided into control group and the experimental group. The traditional vascular surgical anatomy atlas, ultrasound, CT abdominal blood vessel 3D reconstruction, digital subtraction, video and so on were used by 24 residents in the control group, while in the experimental group, on the basis of the traditional teaching, abdominal aortic aneurysm model of 3D printing, true aortic coated stent delivery system were increased. After the teaching, the theory of evaluation (abdominal vascular anatomical features, morphological characteristics and classification of AAA, measurement of various parameters and key points of operation in the EVAR) and satisfaction questionnaire were adopted to evaluate the effect of two kinds of teaching methods. SPSS 19.0 was used to conduct t test on two groups of physician evaluation data. Results The results of theoretical assessment showed that there was no significant difference between the control group and the experimental group in the abdominal vascular anatomical features, the morphological features and the classification of the experimental group (P>0.05) in the examination of the common AAA cases and the complicated AAA cases. However, the experimental group was higher than the control group in the measurement of the parameters of EVAR, and the score of the operation points and the total score, and the difference was statistically significant (t=2.283, t=2.263, P<0.05). The results of the questionnaire showed that the students' satisfaction scores on the teaching satisfaction of the normal and complex AAA cases were better than those of the control group, and the difference was statistically significant (P<0.05). Conclusion The 3D printing model can increase the understanding and mastery of the anatomy and treatment of abdominal aortic aneurysm and improve its learning enthusiasm for vascular surgery. We should make full use of the advantages of 3D printing technology on the basis of retaining the advantages of traditional teaching methods and means, and further enhance the teaching effect. Key words: Standardized residents; 3D printing; Vascular surgery; Abdominal aortic aneurysm

Efficacy and safety of rotational atherectomy combined with drug eluting coronary in the treatment of severe coronary artery calcified lesions

Objective To investigate the efficacy and safety of rotational atherectomy (RA) combined with drug eluting stent (DES) implantation in the treatment of severe coronary artery calcification, and analyze key operation points. Methods The clinical data of sixty-two patients (68 lesions) treated with RA combined with DES from January 2014 to December 2015 were retrospectively analyzed, including the characteristics of operation, postoperative curative effect, complications, incidence of major adverse cardiovascular events (MACE) during hospitalization and follow-up period. Results A total of 75 rotary blur were used in the 62 cases, with an average of(1.18±0.27)per case, the blur diameter/target vessel diameter was (0.54±0.07), the success rate of RA was 98.4% (61/62); A toal of 103 DES were implanted in 61 patients, with an average of(1.67±0.55)per case, average length was(44.5±11.8) mm, immediate DES success rate was 100%.After RA, target vessel diameter was (2.33±0.52) mm, target vessel narrow degree was (29.6±4.8)%, thrombolysis in myocardial infarction grade Ⅲ blood flow ratio was 66.2%, which have been significantly improved compared with preoperation ((0.75±0.21) mm, (82.5±7.2)%, 10.3%)(P<0.05), the target vascular lumen diameter and stenosis of target vessel continued to improve after DES ((3.26±0.43) mm, (8.7±2.1)%, 98.5%) (P<0.05); At 3 days after operation, the left ventricular ejection fraction was significantly higher than that before the operation ( (60.5±5.5)% vs.(56.8±4.7)%)(P<0.05). The incidence of complications associated with interventional procedures was 9.7%, in which 1 case with burr incarceration switched to coronary artery bypass grafting.The incidence of major adverse cardiovascular events incidence during hospitalization was 4.8%, the follow-up period was 9.0-22.0 months.The incidence of major adverse cardiovascular events incidence during follow-up was 8.2%. Conclusion DES implantation following RA in the treatment of severe coronary artery calcification can further improve blood flow and artery stenosis, medium-term efficacy is safe and reliable; standardized RA operation is the key to ensure the success of interventional therapy. Key words: Coronary artery calcification; Coronary rotational atherectomy; Drug eluting stent; Complication; Major adverse cardiovascular events

Synergy evaluation of industry-university-research institute synergetic innovation system based on knowledge creation

Industry-university-research institute (IUR) synergetic innovation (SI) has become the leading-edge innovation mode to promote significant knowledge and technological innovations in China. This article establishes an evaluation index system and evaluation model for system synergy of IUR-SI based on knowledge creation combining the innovation theory with a multi-level extension evaluation method. The index system divides the system synergy of IUR-SI into four subsystems including knowledge synergy capability, relationship synergy capability, innovation synergy capability and synergy performance. we verify the evaluation model taking IUR-SI system of a region in China as an example. The purpose of the paper is to systematically, scientifically describe and analyze various constituent elements of IUR-SI system, as well as various level indicators reflecting efficiency and effectiveness of the system, in order to find the key points of system operation, and enhance the level of collaborative development of scientific and technological innovation systems in China.

Surgical cooperation in laparoscopic radical resection of high rectal cancer with transvaginal specimen extraction and without abdominal incision

Objective To discuss key points of surgical cooperation in laparoscopic radical resection of high rectal cancer with transvaginal specimen extraction and without abdominal incision, so as to provide valuable experience and reference to better cooperation in this surgical method and other similar surgical methods. Methods Clinical data and surgical cooperation of 16 patients undergoing this surgical method were analyzed retrospectively, with key points of the operation nursing summarized. Results All the 16 patients tolerated general anesthesia and carbon dioxide pneumoperitoneum, which made smooth surgeries without conversion to laparotomy and adverse reactions. All the patients were cured and left the hospital with fine condition of recovery. Conclusions Full preoperative preparation of nurses, familiarity of surgical process, good command of laparoscope instruments, usage of special instruments, and rigorous non-bacteria and non-tumor technique operation, are all keys to a successful operation. Key words: Operating Room nursing; Laparoscopic radical resection of rectal cancer; Operative cooperation

Key points of tumor-free operation in laparoscopic resection for colorectal cancer

Key points of tumor-free operation in laparoscopic resection for colorectal cancer

Key Points of Vibration Diagnosis Technology On-Site Operation

The paper introduces the key points of vibration diagnosis technology on-site operation, from the diagnosis, diagnostic object, working condition of equipment, equipment principle and correct data analysis etc., and giving analysis, to prevent the generation of error analysis, to prevent the acquisition signal distortion, improving the diagnosis efficiency and reliability.

Disposal of waste computer hard disk drive: data destruction and resources recycling

An increasing quantity of discarded computers is accompanied by a sharp increase in the number of hard disk drives to be eliminated. A waste hard disk drive is a special form of waste electrical and electronic equipment because it holds large amounts of information that is closely connected with its user. Therefore, the treatment of waste hard disk drives is an urgent issue in terms of data security, environmental protection and sustainable development. In the present study the degaussing method was adopted to destroy the residual data on the waste hard disk drives and the housing of the disks was used as an example to explore the coating removal process, which is the most important pretreatment for aluminium alloy recycling. The key operation points of the degaussing determined were: (1) keep the platter plate parallel with the magnetic field direction; and (2) the enlargement of magnetic field intensity B and action time t can lead to a significant upgrade in the degaussing effect. The coating removal experiment indicated that heating the waste hard disk drives housing at a temperature of 400 °C for 24 min was the optimum condition. A novel integrated technique for the treatment of waste hard disk drives is proposed herein. This technique offers the possibility of destroying residual data, recycling the recovered resources and disposing of the disks in an environmentally friendly manner.

Hydraulic Method for Earthwork Excavation Construction Technology

Hydraulic method for earthwork excavation construction technology has a strong advantage in small environmental pollution, low cost, simple process, energy saving. It follows the idea of a harmonious society and the sustainable development, in line with the energy saving and emission reduction policy that the state promoted and also saving cost. This paper put emphasis on the theory of hydraulic method for earth excavation construction technology, construction process and key operation points, and the problems frequently encountered in construction and countermeasures. Combining with the project in Xinxiang new plain area in Henan province, which is about taking advantage of Yellow River to develop agriculture, the paper illustrates the economic benefit and social benefit of this construction technology.

Recognition and management of hidden related vessel during the operation of microvascular decompression for hemifacial spasm

To investigate the recognition and approach of the hidden related vascular in hemifacial spasm patients during the operation of microvascular decompression. The clinical records of 85 patients of hemifacial spasm were analyzed at our hospital. The hidden related vessel was found in 7 patients. REZ (root entry zone) was surrounded by Teflon cotton slice to separate the vessel from REZ. There were 7 patients of hidden related vessel in 85 patients. And the related vessels were anteroinferior cerebellar artery and its branches. The symptoms became totally relieved after operation and there was no recurrence. The microvascular decompression is an effectively treatment for hemifacial spasm patients. Searching for the related vessel (particularly hidden related vessel) is the most important part of the operation. An effective decompression of REZ is the key point of operation.