Objectives: Evaluation of the effects of withholding plasma during the initial part of the burn shock period (the shock period in the study is estimated as the first 36 hours following the burns) when it will be lost ...Objectives: Evaluation of the effects of withholding plasma during the initial part of the burn shock period (the shock period in the study is estimated as the first 36 hours following the burns) when it will be lost into the interstitial tissues through the permeable capillaries. During that time crystalloids are administered. Another objective is to evaluate the effect of administering normal saline as the crystalloid resuscitation fluid during the initial part of the shock period. Design: A Retrospective 4 years study compares the use of normal saline as the resuscitative intravenous fluid during the first 12 hours post burns followed by intravenous 5% Purified Plasma Protein Fraction (PPPF) during the rest of the shock period i.e. the remaining 24 hours, with the use of the PPPF throughout the burns shock period according to Muir and Barclay formula. Setting: The Plastic Surgery Department and the Department of Laboratory, Directorate General of Khoula Tertiary Hospital, Muscat, Sultanate of Oman. Patients and Methods: The study included 2 groups of patients;Group A: Patients who received 5% Plasma (Human PPPF) throughout the shock period and Group B: Patients who received crystalloids in the form of normal saline during the first 12 hours post burn followed by plasma for the next 24 hours. Monitoring of the patients in both groups was done by using clinical signs of pulse, blood pressure, temperature and urine output and by using laboratory investigations in the form of the haematocrit value, sodium, potassium, chloride, total proteins and albumin levels in the blood at the time of admission and at the end of the shock period. Results: 140 patients were included in the study;64 in Group A and 76 in Group B. There was no mortality and the vital signs were maintained during the shock period in both groups. The mean values of urine output were nearer to the normal level in Group B compared to Group A. The same was observed regarding the Haematocrit value. In both groups the mean values showed no hypoproteinaemia or hypoalbuminaemia at the end of the shock period. There was no hypernatraemia in spite of giving 150 mmol/L of Na during the initial 12 hours post burns in Group B. The mean values of potassium and chloride levels were normal in both groups at the end of the shock period. Conclusion: Giving plasma during the first 12 hours of the burn shock period when the capillary leakage is maximum has no significant benefit. The plasma usage can be reduced by 50% compared to the use of the Muir and Barclay Formula from the beginning of the shock period with reduction of the costs and the possibility of transmission of undetected pathogens by nearly the same value if crystalloids are given during the first 12 hours of burns shock period. The use of isotonic normal saline during the first 12 hours appears more appropriate as it maintains adequate sodium balance to correct the hyponatraemia and at the same time prevents elevation of the serum potassium during the period when potassium is released from the cells. In addition, it does not have a significant reduction on the level of the serum proteins.展开更多
In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solv...In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solving this kind of doubly periodic Riemann boundary value problem of non-normal type and obtain the explicit expressions of solutions and the solvable conditions for it.展开更多
We proposed a kind of doubly periodic Riemann boundary value problem on two parallel curves. By using the method of complex functions, we investigated the method for solving this kind of doubly periodic Riemann bounda...We proposed a kind of doubly periodic Riemann boundary value problem on two parallel curves. By using the method of complex functions, we investigated the method for solving this kind of doubly periodic Riemann boundary value problem of normal type and gave the general solutions and the solvable conditions for it.展开更多
To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which...To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which is defined as a spectrum of peak response acceleration normalized with respect to peak acceleration of the excitation plotted vs.the natural period of the system normalized with respect to the spectrum predominant period,Tp.Based on a statistical analysis of records from the 1999 Chi-Chi earthquake,the conventionally normalized response spectrum(NRS) and the BNRS are examined to account for the effects of soil conditions,epicentral distance,hanging wall and damping.It is found that compared to the NRS the BNRS is much less dependent on these factors.Finally,some simple relationships between the BNRS for a specified damping ratio and that for a damping ratio of 5%,and between the spectra predominant period and epicentral distance for different soil types are provided.展开更多
The Vrancea subcrustal earthquakes of August 30,1986 and May 30,1990 are the two most recent seismic events that have occurred in Romania with moment magnitudes M W ≥ 6.9.The spectral analysis of the strong ground mo...The Vrancea subcrustal earthquakes of August 30,1986 and May 30,1990 are the two most recent seismic events that have occurred in Romania with moment magnitudes M W ≥ 6.9.The spectral analysis of the strong ground motions recorded in Bucharest reveals that despite small differences in magnitude between the 1986 and 1990 earthquakes,their frequency contents are very different,sometimes even opposing.The main focus of this study is to conduct a comparative analysis of the response spectra in terms of the bi-normalized response spectra(BNRS) proposed by Xu and Xie(2004 and 2007) for strong ground motions recorded in Bucharest during these two seismic events.The mean absolute acceleration and relative velocity response spectra for the two earthquakes are discussed and compared.Furthermore,the mean bi-normalized absolute acceleration and normalized relative velocity response spectra with respect to the control period T C are computed for the ground motions recorded in Bucharest in 1986 and 1990.The predominant period T P is also used in this study for the normalization of the spectral period axis.Subsequently,the methodology proposed by Martinez-Perreira and Bommer(1998) is applied in order to estimate the seismic intensity of the two events.The results are discussed and several conclusions regarding the possibility of using the bi-normalized response spectra(BNRS) are given.展开更多
企业与金字塔底层(Bottom of the Pyramid,BOP)群体经济关系的建立是开展包容性创新的重要前提。从BOP群体与企业的关系视角出发,认为二者之间存在"结构洞"现象,即政策制度和配套设施短缺导致的"市场洞",融资困难...企业与金字塔底层(Bottom of the Pyramid,BOP)群体经济关系的建立是开展包容性创新的重要前提。从BOP群体与企业的关系视角出发,认为二者之间存在"结构洞"现象,即政策制度和配套设施短缺导致的"市场洞",融资困难、知识和技能不足导致的"资源洞",信息获取、传播和扩散困难导致的"信息洞"。引入小微企业作为第三方,搭建大企业与BOP群体之间的连接桥。提出在包容性创新情境下,利用小微企业的定位优势、资源优势以及协调优势来实现"结构洞"的跨越,并在从企业能力提升和外部环境两方面提出建议。展开更多
正规基在有限域的许多应用领域中有广泛应用:编码理论、密码学、信号传送等.Z.X.Wan等(Finite Fields and Their Applications,2007,13(4):411-417.)给出了Fqn在Fq上的Ⅰ型最优正规基的对偶基的复杂度为:3n-3(q为偶数)或3n-2(q为奇数)....正规基在有限域的许多应用领域中有广泛应用:编码理论、密码学、信号传送等.Z.X.Wan等(Finite Fields and Their Applications,2007,13(4):411-417.)给出了Fqn在Fq上的Ⅰ型最优正规基的对偶基的复杂度为:3n-3(q为偶数)或3n-2(q为奇数).这是一类类似于k-型高斯正规基的低复杂度正规基.最近,廖群英等(四川大学学报:自然科学版,2010,47(6):1221-1224.)给出了2-型高斯正规基的对偶基及其复杂度.在此基础上,给出了一般的k-型高斯正规基N的对偶基以及当n≥k≥1时,N的复杂度的一个上界.进而证明了当k=3时,此上界可达到,并由此给出了所有(弱)自对偶的k-型高斯正规基.展开更多
包容性创新是实现企业可持续发展的重要途径。然而,企业在开展包容性创新时往往受到传统经营惯性、金字塔底层(bottom of the pyramid,BOP)市场缺陷和包容性创新营利阻碍等多方面的惯性障碍,不利于企业创新效率提升。在理论研究的基础上...包容性创新是实现企业可持续发展的重要途径。然而,企业在开展包容性创新时往往受到传统经营惯性、金字塔底层(bottom of the pyramid,BOP)市场缺陷和包容性创新营利阻碍等多方面的惯性障碍,不利于企业创新效率提升。在理论研究的基础上,探究包容性创新的内涵特征,分析形成企业包容性创新惯性障碍的内在原因,构建创新理念转换机制、共益性结构洞桥接机制和包容性创新商业模式探索机制,并提出相关对策与建议。展开更多
柔性薄壁轴承的内外圈是椭圆,这使得它和普通滚动轴承的振动特性完全不同。这种轴承旋转过程中椭圆长短轴会对轴承造成周期性冲击,这种正常的周期性冲击和轴承元件损伤引起的故障周期性冲击混合在一起,掩盖了故障周期性冲击。分析了这...柔性薄壁轴承的内外圈是椭圆,这使得它和普通滚动轴承的振动特性完全不同。这种轴承旋转过程中椭圆长短轴会对轴承造成周期性冲击,这种正常的周期性冲击和轴承元件损伤引起的故障周期性冲击混合在一起,掩盖了故障周期性冲击。分析了这种正常周期性冲击的频率分布特点,根据奇异值和频率的内在关系,提出利用奇异值分解(Singular Value Decomposition,SVD)来消除这种正常周期性冲击,选择正常周期性冲击的频率成分对应的奇异值进行SVD重构,可以准确地分离出这种正常冲击,从而消除其对故障周期性冲击的干扰。进而采用连续Morlet小波变换对消除了正常周期性冲击的柔性薄壁轴承振动信号进行故障冲击特征提取,选择峭度最大的尺度为故障特征尺度,清晰地提取到了柔性薄壁轴承的故障冲击特征,故障特征提取效果优于没有消除正常冲击时的故障特征提取效果。展开更多
文摘Objectives: Evaluation of the effects of withholding plasma during the initial part of the burn shock period (the shock period in the study is estimated as the first 36 hours following the burns) when it will be lost into the interstitial tissues through the permeable capillaries. During that time crystalloids are administered. Another objective is to evaluate the effect of administering normal saline as the crystalloid resuscitation fluid during the initial part of the shock period. Design: A Retrospective 4 years study compares the use of normal saline as the resuscitative intravenous fluid during the first 12 hours post burns followed by intravenous 5% Purified Plasma Protein Fraction (PPPF) during the rest of the shock period i.e. the remaining 24 hours, with the use of the PPPF throughout the burns shock period according to Muir and Barclay formula. Setting: The Plastic Surgery Department and the Department of Laboratory, Directorate General of Khoula Tertiary Hospital, Muscat, Sultanate of Oman. Patients and Methods: The study included 2 groups of patients;Group A: Patients who received 5% Plasma (Human PPPF) throughout the shock period and Group B: Patients who received crystalloids in the form of normal saline during the first 12 hours post burn followed by plasma for the next 24 hours. Monitoring of the patients in both groups was done by using clinical signs of pulse, blood pressure, temperature and urine output and by using laboratory investigations in the form of the haematocrit value, sodium, potassium, chloride, total proteins and albumin levels in the blood at the time of admission and at the end of the shock period. Results: 140 patients were included in the study;64 in Group A and 76 in Group B. There was no mortality and the vital signs were maintained during the shock period in both groups. The mean values of urine output were nearer to the normal level in Group B compared to Group A. The same was observed regarding the Haematocrit value. In both groups the mean values showed no hypoproteinaemia or hypoalbuminaemia at the end of the shock period. There was no hypernatraemia in spite of giving 150 mmol/L of Na during the initial 12 hours post burns in Group B. The mean values of potassium and chloride levels were normal in both groups at the end of the shock period. Conclusion: Giving plasma during the first 12 hours of the burn shock period when the capillary leakage is maximum has no significant benefit. The plasma usage can be reduced by 50% compared to the use of the Muir and Barclay Formula from the beginning of the shock period with reduction of the costs and the possibility of transmission of undetected pathogens by nearly the same value if crystalloids are given during the first 12 hours of burns shock period. The use of isotonic normal saline during the first 12 hours appears more appropriate as it maintains adequate sodium balance to correct the hyponatraemia and at the same time prevents elevation of the serum potassium during the period when potassium is released from the cells. In addition, it does not have a significant reduction on the level of the serum proteins.
文摘In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solving this kind of doubly periodic Riemann boundary value problem of non-normal type and obtain the explicit expressions of solutions and the solvable conditions for it.
文摘We proposed a kind of doubly periodic Riemann boundary value problem on two parallel curves. By using the method of complex functions, we investigated the method for solving this kind of doubly periodic Riemann boundary value problem of normal type and gave the general solutions and the solvable conditions for it.
基金Heilongjiang Natural Science Foundation Under Project No.ZGJ03-03the Research Fund for the Doctoral Program of Higher Education of China Through Project No.20030213042
文摘To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which is defined as a spectrum of peak response acceleration normalized with respect to peak acceleration of the excitation plotted vs.the natural period of the system normalized with respect to the spectrum predominant period,Tp.Based on a statistical analysis of records from the 1999 Chi-Chi earthquake,the conventionally normalized response spectrum(NRS) and the BNRS are examined to account for the effects of soil conditions,epicentral distance,hanging wall and damping.It is found that compared to the NRS the BNRS is much less dependent on these factors.Finally,some simple relationships between the BNRS for a specified damping ratio and that for a damping ratio of 5%,and between the spectra predominant period and epicentral distance for different soil types are provided.
基金provided by the Romanian National Authority for Scientific Research (ANCS) under Grant Number 72/2012
文摘The Vrancea subcrustal earthquakes of August 30,1986 and May 30,1990 are the two most recent seismic events that have occurred in Romania with moment magnitudes M W ≥ 6.9.The spectral analysis of the strong ground motions recorded in Bucharest reveals that despite small differences in magnitude between the 1986 and 1990 earthquakes,their frequency contents are very different,sometimes even opposing.The main focus of this study is to conduct a comparative analysis of the response spectra in terms of the bi-normalized response spectra(BNRS) proposed by Xu and Xie(2004 and 2007) for strong ground motions recorded in Bucharest during these two seismic events.The mean absolute acceleration and relative velocity response spectra for the two earthquakes are discussed and compared.Furthermore,the mean bi-normalized absolute acceleration and normalized relative velocity response spectra with respect to the control period T C are computed for the ground motions recorded in Bucharest in 1986 and 1990.The predominant period T P is also used in this study for the normalization of the spectral period axis.Subsequently,the methodology proposed by Martinez-Perreira and Bommer(1998) is applied in order to estimate the seismic intensity of the two events.The results are discussed and several conclusions regarding the possibility of using the bi-normalized response spectra(BNRS) are given.
文摘企业与金字塔底层(Bottom of the Pyramid,BOP)群体经济关系的建立是开展包容性创新的重要前提。从BOP群体与企业的关系视角出发,认为二者之间存在"结构洞"现象,即政策制度和配套设施短缺导致的"市场洞",融资困难、知识和技能不足导致的"资源洞",信息获取、传播和扩散困难导致的"信息洞"。引入小微企业作为第三方,搭建大企业与BOP群体之间的连接桥。提出在包容性创新情境下,利用小微企业的定位优势、资源优势以及协调优势来实现"结构洞"的跨越,并在从企业能力提升和外部环境两方面提出建议。
文摘正规基在有限域的许多应用领域中有广泛应用:编码理论、密码学、信号传送等.Z.X.Wan等(Finite Fields and Their Applications,2007,13(4):411-417.)给出了Fqn在Fq上的Ⅰ型最优正规基的对偶基的复杂度为:3n-3(q为偶数)或3n-2(q为奇数).这是一类类似于k-型高斯正规基的低复杂度正规基.最近,廖群英等(四川大学学报:自然科学版,2010,47(6):1221-1224.)给出了2-型高斯正规基的对偶基及其复杂度.在此基础上,给出了一般的k-型高斯正规基N的对偶基以及当n≥k≥1时,N的复杂度的一个上界.进而证明了当k=3时,此上界可达到,并由此给出了所有(弱)自对偶的k-型高斯正规基.
文摘包容性创新是实现企业可持续发展的重要途径。然而,企业在开展包容性创新时往往受到传统经营惯性、金字塔底层(bottom of the pyramid,BOP)市场缺陷和包容性创新营利阻碍等多方面的惯性障碍,不利于企业创新效率提升。在理论研究的基础上,探究包容性创新的内涵特征,分析形成企业包容性创新惯性障碍的内在原因,构建创新理念转换机制、共益性结构洞桥接机制和包容性创新商业模式探索机制,并提出相关对策与建议。
文摘柔性薄壁轴承的内外圈是椭圆,这使得它和普通滚动轴承的振动特性完全不同。这种轴承旋转过程中椭圆长短轴会对轴承造成周期性冲击,这种正常的周期性冲击和轴承元件损伤引起的故障周期性冲击混合在一起,掩盖了故障周期性冲击。分析了这种正常周期性冲击的频率分布特点,根据奇异值和频率的内在关系,提出利用奇异值分解(Singular Value Decomposition,SVD)来消除这种正常周期性冲击,选择正常周期性冲击的频率成分对应的奇异值进行SVD重构,可以准确地分离出这种正常冲击,从而消除其对故障周期性冲击的干扰。进而采用连续Morlet小波变换对消除了正常周期性冲击的柔性薄壁轴承振动信号进行故障冲击特征提取,选择峭度最大的尺度为故障特征尺度,清晰地提取到了柔性薄壁轴承的故障冲击特征,故障特征提取效果优于没有消除正常冲击时的故障特征提取效果。
