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61.
This paper presents an extension to the existing dynamic relaxation method to include equality constraint conditions in the process. The existing dynamic relaxation method is presented as a general, gradient‐based, minimization technique. This representation allows for the introduction of the projected gradient, discrete parallel transportation and pull back operators that enable the formulation of the geodesic dynamic relaxation method, a method that accounts for equality constraint conditions. The characteristics of both the existing and geodesic dynamic relaxation methods are discussed in terms of the system's conservation of energy, damping (viscous, kinetic, and drift), and geometry generation. Particular attention is drawn to the introduction of a novel damping approach named drift damping. This technique is essentially a combination of viscous and kinetic damping. It allows for a smooth and fast convergence rate in both the existing and geodesic dynamic relaxation processes. The case study was performed on the form‐finding of an iconic, ridge‐and‐valley, pre‐stressed membrane system, which is supported by masts. The study shows the potential of the proposed method to account for specified (total) length requirements. The geodesic dynamic relaxation technique is widely applicable to the form‐finding of force‐modeled systems (including mechanically and pressurized pre‐stressed membranes) where equality constraint control is desired. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
62.
To verify the cushion performance of transport packaging, two traditional drop test methods – free fall and controlled shock tests – and a traditional simulation method are often used. However, it is difficult to assure the safety of a test product when the traditional drop test method is applied, and results from the traditional simulation method are not sufficiently accurate to be used to test packaging material. Therefore, we propose a new test method called ‘the hybrid drop test’ by integrating the traditional drop test and simulation methods. The hybrid drop test ensures the safety of the test product and improves test efficiency. The results of the verification test show that this new drop test method can be applied to test the cushion performance of pulp mould transport packaging. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
63.
In recent years, the requirement for the reduction of energy consumption has been increasing to solve the problems of global warming and the shortage of petroleum resources. A latent heat recovery type heat exchanger is one of the effective methods for improving thermal efficiency by recovering latent heat. This paper describes the heat transfer and pressure loss characteristics of a latent heat recovery type heat exchanger having straight fins (fin length: 65 mm or 100 mm, fin pitch: 2.5 mm or 4 mm). These were clarified by measuring the exchange heat quantity, the pressure loss of the heat exchanger, and the heat transfer coefficient between the outer fin surface and gas. The effects of fin length and fin pitch on heat transfer and pressure loss characteristics were clarified. Furthermore, equations for predicting the heat transfer coefficient and pressure loss which are necessary for heat exchanger design were proposed. ©2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(4): 230– 247, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20153 Copyright © 2004 Wiley Periodicals, Inc.  相似文献   
64.
Some studies for radiological protection of the environment have been made at the National Institute of Radiological Sciences (NIRS). Transfer of radionuclides and related elements has been investigated for dose estimation of non-human biota. A parameter database and radionuclide transfer models have been also developed for the Japanese environments. Dose (rate)-effect relationships for survival, growth and reproduction have been investigated in conifers, Arabidopsis, fungi, earthworms, springtails, algae, duckweeds, daphnia and medaka. Also genome-wide gene expression analysis has been carried out by high coverage expression profiling (HiCEP). Effects on aquatic microbial communities have been studied in experimental ecosystem models, i.e., microcosms. Some effects were detected at a dose rate of 1 Gy day(-1) and were likely to arise from interspecies interactions. The results obtained at NIRS have been used in development of frameworks for environmental protection by some international bodies, and will contribute to environmental protection in Japan and other Asian countries.  相似文献   
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BACKGROUND/PURPOSE: Fibronectin (FN) plays an important role in fibrin matrix formation during the wound healing process. The authors investigated whether exogenous FN increases the bursting strength (BS) of surgical wounds in malnourished rats. METHODS: Ninety rats were grouped according to three nutritional conditions (n = 30 in each group). All animals underwent a transverse celiotomy after 3 weeks of feeding, and FN (2 mg/body/day) was given postoperatively to 15 rats in each of the three groups. Wound BS was measured on postoperative days (PODs) 3, 5, and 7 after removal of the sutures. RESULTS: BS in normally nourished rats (group N; 142.6+/-23.4 mmHg) was significantly higher than that in protein malnourished rats (group PM, 110.2+/-11.2 mm Hg) and protein/ calorie (Cal)-malnourished rats (group PCM, 76.5+/-10.7 mm Hg) on POD 7 (P<.01). However, BS values for groups PM + FN (147.0+/-21.1 mmHg) and PCM + FN (115.1+/-28.9 mm Hg) were intensified significantly in comparison with groups PM and PCM (P<.01). Plasma FN levels in rats of the three FN nontreated groups were similarly decreased on POD 3 or 5, but returned to the preoperative level on POD 7, whereas those for the other three FN-treated groups increased after POD 3. CONCLUSION: Intravenous administration of FN might strengthen the weakened wounds of malnourished animals.  相似文献   
68.
Japanese law provides for regular medical examinations for the aged. A simulation study to determine the relationship between medical expenditures of cardiovascular disease patients and government-sponsored health check-ups for the aged was conducted in a small community town in Kanagawa Prefecture. The results showed that medical expenditures decreased in accordance with an increase in health screening. However, medical expenditure for out-patients increased slightly with an increase in screening for those cardiovascular disease patients who had not received treatment prior to the government health checkup.  相似文献   
69.
Results 2 1/2 years after an enuresis nocturna training are presented, including rate of success, percentage and duration of relapse for 113 children (mean age 11.6 year at the start of the training). The bibliotherapeutic treatment by parents did not require any intervention by a professional. Behaviour of parents in the event of a relapse differed between training conditions. Children in the Arousal condition recovered faster from a relapse, 90% of their parents used the Arousal training again at relapse or did not intervene at all and none of them consulted a professional. Clearly they had confidence in the method of Arousal training: combining the alarm device with reinforcement for correct behaviour at the time the alarm goes off. Parents in control conditions did not use the alarm device as often as the parents in the Arousal condition, but tried other means with less success, including consulting professionals.  相似文献   
70.
Two cases are presented in which a scapular osteocutaneous flap and a latissimus dorsi musculocutaneous flap were applied as combined flaps with a single pedicle, to repair massive soft-tissue defects resulting from tibial hemisection in the lower limb. In each case, the oval-shaped donor site was divided into two parts (an ascending scapular flap and a latissimus dorsi flap, respectively) to repair the resected area, using a vertically designed, combined flap from the dorsolateral region. Consequently, after flap elevation, the donor site could be closed primarily and functions of the affected limb could be completely reconstructed. For reconstruction of defects too large to be covered with a single flap, the vertical double flap design of a combined ascending scapular and latissimus dorsi flap is a good alternative. It has the merits of easy dissection, broad area skin coverage and it also provides a composite flap that contains a scapular bone graft. Moreover, it allows a simple microsurgical anastomosis, as well as direct closure of the donor site. In addition, when the recipient site is on the lower leg, flap elevation can be carried out simultaneously with surgery at the recipient site. This means that the operative time can be shortened.  相似文献   
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