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With the rapid development of renewable energy (RE) and the continuous progress of smart grid, the energy consumption characteristic design of modern power system is developing towards a more flexible and economical microgrid (MG). Meanwhile, the high participation of multi-agent integrated energy in MG brings challenges to the efficient and economic operation of the system. Aiming at the complex capacity configuration of MG with multi-functional interaction, a combined capacity optimization method for a typical independent MG including photovoltaic (PV), wind turbines (WT), diesel generators (DG) and battery energy storage system (BESS) is proposed. On the one hand, the models of PV, WT, DG, BESS and electric vechicle (EV) charging load are established. On the other hand, the EV charging load are considered, and the capacity configuration is optimized to minimize the cost, reduce greenhouse gas emissions and energy waste. The results show that the combination of PV-WT-BESS-DG is not only more reliable but also more economical. This study can provide support for the optimal allocation of MG capacity.

In order to improve the drilling efficiency and reduce the weight of the anchor recycling equipment,it took spiral drill pipe of the anchor recycling equipment as the research object,by selecting the inner and outer diameter of the drill pipe,blade thickness,pitch,helix angle,speed,blade number and blade height as the optimizing parameters. It chosen the highest efficiency in transport,the lightest in weight and the highest rate in secondary crushing as the ideal goal of the drill pipe optimization,the result indicates that the drilling efficiency is increased by 31. 4%,the weight is reduced by 12. 7% and the secondary crushing rate is increased by 48. 7% based on particle swarm optimization. The efficiency of the recovering has been improved,and the wear-resisting degree and intensity of the spiral pipe have been enhanced.

For analyzing the influence of related factors on gear thermo- elastic coupling deformation,based on the response surface method and the sample- point test method,the function relation between the gear thermo- elastic coupling deformation and related factor is constructed,gained by analyzing,the influence factors of tooth width,rotational speed,torque,boundary temperature on gear maximum thermo- elastic coupling deformation are- 0. 207,0. 273,0. 321 and 0. 199. According to the size and the positive and negative of these influence factors,the boundary temperature,tooth width,speed and torque have larger and larger influence on maximum deformation. The maximum deformation increased with the rotational speed,torque and boundary temperature,and decreased with the tooth width.

Objective: To investigate the effectiveness of repairing severe cicatricial contracture deformity in the web-space by kite-like incision combined with full-thickness skin grafting., Methods: Between June 2008 and September 2011, 31 patients (87 web-spaces) with severe cicatricial contracture deformities in the web-spaces were treated. There were 24 males and 7 females, aged 5-43 years (median, 22 years). The causes of injuries were flame burn (26 cases), scald (3 cases), electric arc burn (1 case), and chemical burn (1 case). The degree of burn was deep second degree (14 cases) and third degree (17 cases). The interval time from injury to operation was 10 months to 17 years (median, 2.2 years). The kite-like incision was marked on the scar in the web-space. The rhombic scar between the adjacent metacarpophalangeal joints was excised, and cicatricial contracture was released completely. The secondary wound in the web-space was repaired with full-thickness autogeneic skin grafting. The secondary wound at donor site was directly sutured., Results: All full-thickness skin grafts survived well. The incisions at donor sites healed primarily. Of 31 patients, 29 (82 web-spaces) were followed up 6-18 months (mean, 13 months). The sizes and depths of reconstructed web-spaces were similar to those of normal ones. No secondary cicatricial contracture was observed, and the function of fingers recovered well., Conclusion: The short-term effectiveness is satisfactory by kite-like incision combined with full-thickness skin grafting for repairing severe cicatricial contracture deformities in the web-space, while the long-term effectiveness needs further observation.

Objective: To investigate the feasibility of repairing secondary wounds after scar excision in patients with scar contracture in whole dorsum of the hands by expanded full-thickness skin grafts., Methods: Between February 2008 and February 2011, 15 patients (19 hands) with scar contracture in whole dorsum of the hands were treated. There were 12 males (14 hands) and 3 females (5 hands), aged 18-43 years (mean, 28.6 years). The disease duration was 6-22 months (mean, 13.2 months). All cases complicated by different degrees of metacarpophalangeal joint extension deformity and interphalangeal joint flexion deformity. In one-stage operation, soft tissue expanders were implanted at donor sites, and the time of water injection was 4-5 months; in two-stage operation, scar was excised and secondary wound (14 cm x 9 cm-25 cm x 16 cm in size) was repaired with the expanded full-thickness skin grafts., Results: After one-stage operation, the others had good blood supply except 1 case of skin necrosis in the center of expanded skin flap. After two-stage operation, the full-thickness skin grafts survived well in 18 hands; subepidermal effusion occurred in 1 hand, which was cured after changing dressing. The incisions at donor sites healed well in all cases. All patients were followed up 6-18 months (mean, 13.7 months). The grafts were excellent in color, texture, and elasticity, and no hypertrophic scar was observed at the edge and joint of the grafts. The hand function recovered well; the flexion and extension of wrist joint, metacarpophalangeal joint and interphalangeal joint were normal., Conclusion: The expanded full-thickness skin graft is a suitable solution to repair effectively scar contracture in whole dorsum of the hands because it has good results in the cosmetic appearance and function recovery of the hands.

Objective: To evaluate the clinical effect and the pathological characteristics of acellular allogeneic dermal matrix in repairing unstable burn scar., Methods: From January 2007 to June 2008, 19 cases of unstable burn scars (24 parts) were treated, including 16 males (20 parts) and 3 females (4 parts) with a median age of 27 years (range, 3-58 years). The injury was caused by flame (14 cases, 18 parts), electricity (4 cases, 5 parts), and hot water (1 case, 1 part). The unstable burn scars located on hands (8 cases), forearms (2 cases), thighs (3 cases), legs (2 cases), feet (2 cases), chest (1 case), and abdomen (1 case). Scar formed for 3 months to 1 year. The area of defect varied from 7 cm x 5 cm to 22 cm x 15 cm after scar removal. Defects were covered with acellular allogeneic dermal matrix and autogenous split-thickness skin graft. At 6-18 months after operation, the pathological observations of the epidermis, the basal membrane, and structural components of the dermis were done., Results: All wounds healed by first intention. Scar ulcer disappeared completely in 18 cases and the composite skin grafts all survived. Some blisters occurred in 1 case and were cured after dressing changing. All patients were followed up 10 months to 2 years (18 months on average). The grafted-skin was excellent in the appearance, texture, and elasticity. The function recovered well. Only superficial scar was observed at skin donor sites. Pathological observation showed that the epidermis and the basal membrane of the skin grafts were similar to that of normal skin, and no significant difference was found in newly capillaries between them. Collagen fibers arranged regularly, and there were few inflammatory cells in the matrix., Conclusion: Acellular allogeneic dermal matrix with autogenous split-thickness skin graft may effectively repair the wound after removing the unstable burn scar, and its structure is similar to that of normal skin.

Objective: To compare the effects of two different cryoprotectants on human desmoglein 1 (Dsg 1), and to provide experimental basis for the optimization of cryoprotectant., Methods: Five donated thin split-thickness skin grafts were used, and the experiment was conducted within 4 hours after skin grafts harvest. The skin grafts were divided into 3 groups: group A (n = 2) in which skin grafts were immersed in 0.5 mol/L trehalose/DMSO; group B (n = 2) in which skin grafts were immersed in DMSO/propanediol; group C (n = 1) in which fresh skin graft received no further treatment. Groups A and B were stored in -196 degree C liquid nitrogen for 7 and 21 days, respectively, and then underwent experiment. Immunohistochemistry staining observation was performed on each group, RT-PCR method was used to detect the expression of Dsg 1 in skin., Results: The immunohistochemistry staining showed that the protein in groups A and B was stained brown-yellow and distributed evenly 7 days after cryopreservation; the expression signal of epidermal basal cell was similar to that of group C; absorbance (A) value of groups A, B and C was 0.285 +/- 0.006, 0.284 +/- 0.004 and 0.287 +/- 0.008, respectively, suggesting there was no significant difference between groups A and B and group C (P > 0.05). At 21 days after cryopreservation, the expression of positive cells in group B decreased; no obvious decrease was observed in group A, A value of groups A and B was 0.282 +/- 0.004 and 0.275 +/- 0.005, respectively, indicating there was a significant difference between group B and groups A and C (P < 0.05). RT-PCR detection showed that A value of groups A and B at 7 days after cryopreservation was 0.810 +/- 0.012 and 0.803 +/- 0.008, respectively; A value of groups A and B at 21 days after cryopreservation was 0.806 +/- 0.008 and 0.782 +/- 0.013, respectively; and the A value of group C was 0.814 +/- 0.012, indicating there was significant difference between group B and groups A and C at 21 days after cryopreservation (p < 0.05), and no significant differences among groups were noted at other time points (P > 0.05)., Conclusion: Trehalose/DMSO is better than traditional cryoprotectant DMSO/propanediol in protecting Dsg 1 of human skin.

Objective: To compare the effect of trehalose with that of different traditional cryoprotectants on human skin and to detect the new protection mechanism of trehalose in hypothermia., Methods: The skins to be cryopreserved were first treated with DMSO/Propyleneglycol (D/P group), trehalose/DMSO (T/D group), DMSO/serumfree keratinocyte medium (D/K group), DMEM (DMEM group), respectively, so as to be compared with fresh skin (control grouop). Then the histological structure of skin of different groups was observed and analyzed by pathological technology (SP immunohistochemistry, DAB staining). Furthermore, the influence of trehalose on alpha-actinin at gene level with RT-PCR was investigated. The viability of skin in 5 respective groups was evaluated by using succinate dehydrogenase (SDH). The experiments were carried out 14 days after cryopreservation., Results: The results of immunohistochemistry showed that A values of control group, T/D group, D/P group, D/K group and DMEM group were 27.50 +/- 7.92, 18.40 +/- 5.81, 13.10 +/- 5.11, 11.50 +/- 4.54 and 5.30 +/- 2.14, respectively. There was no significant difference between control group and T/D group (P > 0.05), but control group was significantly different from the other groups (P < 0.05). The results of PCR studies showed that A values of control group, T/D group, D/P group, D/K group and DMEM group were 0.816 +/- 0.134, 0.723 +/- 0.245, 0.564 +/- 0.265, 0.245 +/- 0.071 and 0.148 +/- 0.048, respectively. Control group was not significantly different from T/D group and D/P group (P > 0.05), but was significantly different from D/K group and DMEM group (P < 0.05). The results of SDH showed that A valuse of control group, T/D group, D/P group, D/K group and DMEM group were 18.2 +/- 3.7, 12.3 +/- 3.6, 10.2 +/- 2.4, 7.3 +/- 2.1 and 5.7 +/- 1.5, respectively. There was no significant difference between control group and T/D group (P > 0.05), while control group was significantly different from the other groups (P < 0.05)., Conclusion: The results suggest that cryopreservation protocol-trehalose/DMSO is better than the traditional cryoprotectant for cryopreservation on alpha-actinin of human skin.

Objective: We aimed to investigate the characteristic of pneumoconiosis on coal miners and provide scientific evidences for its prevention., Methods: To analyze the data of pneumoconiosis from one coal mine with the historical study and to predict its development tendency by the grey model of GM (1,1)., Results: (1) The year of work experience of pneumoconiosis (stage I) was 19.9 years and the age of its diagnosis (stage I) was 51.4 years. There was an obvious tendency that they became longer with years' back-shift. (2) During near forty years, the progression rates of pneumoconiosis from stage I to II and II to III were 13.6% and 11.2%, and the mean time was 8.3 and 8.1 years, respectively. It was obvious that the progression rate decreased gradually and the span prolonged with years' back-shift. (3) The complication rate of pneumoconiosis with lung tuberculosis was 12.5% and it increased with the progression of pneumoconiosis. The rate in dead cases was significantly higher than that in live cases (P < 0.01). (4) The sequence of death causes was pneumoconiosis (20.0%), lung tuberculosis (18.3%), chronic cor pulmonale (17.9%), and pulmonary carcinoma (9.0%), et al. (5) It was predicted that there would be 28 new cases every year during 2001-2020 years and the accumulated numbers of pneumoconiosis would be 2854 cases in 2020, but with a downward trends in the prevalence of -1.7%., Conclusion: It was suggested that the prevalence of pneumoconiosis should decrease obviously. However, it still remains a challenge about the task of effectively preventing and curing it or its complication.

Objective: the main purpose of this study is to develop an assay for detection of skin viability in situ., Methods: Two nucleic acid dyes, SYTO 13 and ethidium bromide (EB), are used to assess the viability of skin tissue. The viability of cells can be determined by different colors under fluorescence microscope. In this study, the recovery of skin restored at 4 degrees C for different periods is measured by SYTO/EB dyes and a type of indirect assessment, WST-1. Then both results are compared., Results: The results measured by two methods showed that the viability of skin tissue was nearly 30% after two weeks storage. At any point of experiment, the data from two methods have not obvious variance., Conclusion: The assessment of skin viability by SYTO/EB is also quick, sensitive and convenient. At the same time the viability of any type of cells can be observed in situ. So it can be considered as an available method for detection of skin viability.