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51.
In this paper, using Laplace transform, we will calculate the joint density of twopercentiles of stock prices in the Black–Sholes model and make the price of exchange options of such twopercentiles.  相似文献   
52.
[目的]以测土配方施肥技术为例,侧重于农户心理机制分析农户对环境友好型技术采纳意愿的影响因素,以期为促进环境友好型技术推广的政策制定提供参考。[方法]文章基于技术接受模型理论,运用江西省8县554户农户调查数据,借助结构方程模型对农户环境友好型农业技术采纳意愿的影响因素进行实证分析。[结果]效果展示对农户采纳意愿影响最为显著,且通过感知有用性和感知易用性对农户意愿产生正向影响;感知易用性和感知有用性是影响农户意愿的重要因素,且感知易用性对感知有用性能够产生正向影响;社会影响对农户采纳意愿和感知易用性有显著正向影响,但对感知有用性的影响作用不显著;采纳条件对农户感知有用性、易用性都没有显著性的影响,但对采纳意愿具有显著的负向影响作用。[结论]重视技术的效果展示,提升农户对环境友好型技术成效的认可程度;开发简捷易行的使用方法并加大宣传力度,提升农户对环境友好型技术的易用性和有用性感知;改善技术采纳条件,创新技术推广机制。  相似文献   
53.
Abstract

Objective:

To perform an economic evaluation of a specific brand of partially hydrolyzed infant formula (PHF-W) in the prevention of atopic dermatitis (AD) among Australian infants.

Methods:

A cost-effectiveness analysis was undertaken from the perspectives of the Department of Health and Aging (DHA), of the family of the affected subject and of society as a whole in Australia, based on a decision-analytic model following a hypothetical representative cohort of Australian newborns who are not exclusively breastfed and who have a familial history of allergic disease (i.e., are deemed ‘at risk’). Costs, consequences, and incremental cost-effectiveness ratios (ICER) were calculated for PHF-W vs standard cow’s milk based infant formula (SF), and, in a secondary analysis, vs extensively hydrolyzed infant formula (EHF-Whey), when the latter was used for the prevention of AD.

Results:

From a representative starting cohort of 87,724 ‘at risk’ newborns in Australia in 2009, the expected ICERs for PHF-W vs SF were AU$496 from the perspective of the DHA and savings of AUD1739 and AU$1243 from the family and societal perspectives, respectively. When compared to EHF-Whey, PHF-W was associated with savings for the cohort of AU$5,183,474 and AU$6,736,513 from the DHA and societal perspectives.

Limitations:

The generalizability and transferability of results to other settings, populations, or brands of infant formula should be made with caution. Whenever possible, a conservative approach directing bias against PHF-W rather than its comparators was applied in the base case analysis. Assumptions were verified in one-way and probabilistic sensitivity analyses, which confirmed the robustness of the model.

Conclusions:

PHF-W appears to be cost-effective when compared to SF from the DHA perspective, dominant over SF from the other perspectives, and dominant over EHF-Whey from all perspectives, in the prevention of AD in ‘at risk’ infants not exclusively breastfed, in Australia.  相似文献   
54.
We derive expressions for the density of the time to ruin given that ruin occurs in a Sparre Andersen model in which individual claim amounts are exponentially distributed and inter-arrival times are distributed as Erlang(n,?β). We provide numerical illustrations of finite time ruin probabilities, as well as illustrating features of the density functions.  相似文献   
55.
随着我国经济的快速发展,智能电网将在未来经济建设和社会发展中发挥举足轻重的作用。我国智能电网的实现和应用呼唤更为科学、高效、合理的电力调节。文章创造性地运用新政下的装机容量计算公式对水电功能转换进行深入分析与综合研究,指出了水电行业在新时期下将发挥至关重要的作用。  相似文献   
56.
蔡代平 《价值工程》2012,31(31):251-254
本文运用观察实验和数学方法,给出了匀速圆周运动向心力公式的几种推导方法,以促进人们更加深刻地认识、理解和应用匀速圆周运动向心力。  相似文献   
57.
为了全面反映瓜蒌配方颗粒所含多种组分,明确瓜蒌配方颗粒HPLC指纹图谱的测定方法,对10批瓜蒌配方颗粒进行了HPLC指纹图谱测定及相似度评价。采用HPLC方法,色谱柱为GL Sciences公司InertSustain AQ-C_(18)柱(4.6 nm×250 nm,5μm),以甲醇-0.1%甲酸水溶液为流动相,梯度洗脱,检测波长为260 nm,流速为0.8 mL/min,柱温为25℃,对瓜蒌配方颗粒指纹图谱测定结果进行了相似度评价。结果表明,10批瓜蒌配方颗粒指纹图谱中呈现16个共有峰,相似度均大于0.960,表明瓜蒌配方颗粒具有良好的一致性;此外,在16个共有峰中指认出腺嘌呤、尿苷2个化学成分。瓜蒌配方颗粒指纹图谱反映了瓜蒌配方颗粒的多组分面貌,可为瓜蒌配方颗粒的多组分质量控制提供参考依据。  相似文献   
58.
There are various risks associated with incorrect preparation and storage of infant formula, including microbiological hazards. Preparing and storing reconstituted infant formula correctly can reduce potential risks. The product label on infant formula is often the main source of information for caregivers on the correct handling of infant formula. Caregivers’ ability to understand and follow preparation and storage instructions is, therefore, of high importance in the safe use of infant formula. This study aims to increase understanding of how Australian caregivers perceive, interpret and use mandatory and voluntary “on-pack” label information when preparing and storing infant formula. An eye-tracking task requiring caregivers (n = 30) to prepare an unfamiliar infant formula product while wearing Tobi Pro 2 Glasses revealed that almost all caregivers look at the preparation instructions (93%), though fewer look at the warning advice (43%) and storage instructions (27%). Findings from retrospective think-aloud and in-depth interviews conducted immediately after the eye-tracking task, revealed that while preparation instructions are generally understood, they are not always adhered to, with most caregivers making modifications for convenience. Lack of awareness and low perceived risk to the infant’s health were other reasons for non-adherence. These findings suggest that mandated food-safety elements on infant formula products need to be more noticeable, clearer and more specific with respect to potential infant health risks associated with non-adherence, to ensure safe preparation and storage by all caregivers. These findings will be used to inform a review of the labelling requirements for infant formula products.  相似文献   
59.
在当前社会背景下,人们对饮食结构与营养的关注程度不断提升,速食杂粮粉兼顾保健、食疗双重功效而深受广大消费者欢迎。基于此,本研究选用紫薯、燕麦、小米和大豆为主要杂粮材料,根据不同配比划分为9个实验组别,通过感官评定、产品指标(保水性、溶解率、膨胀率、凝沉率和透光率)测定了解不同配比组合下的产品品质,确定杂粮粉配方。结果表明,紫薯、燕麦、小米和大豆比例为25∶45∶15∶15时,制得的速食杂粮粉品质良好,适宜食用。  相似文献   
60.
为快速鉴别杜仲不同炮制品配方颗粒,建立了红外光谱法,结合二阶导数光谱及二维相关光谱法,分析不同炮制品配方颗粒的光谱特征。结果表明:杜仲不同炮制品配方颗粒的红外光谱基本相似,仅在1 603,1 514,1 420cm~(-1)处出现位置变化;在800~1 600cm~(-1)范围内,二阶导数光谱吸收峰有明显的强度、形状、位置变化;1 800~1 000cm~(-1)范围内,二维相关光谱差异明显。通过比较杜仲不同炮制品的红外光谱图、二阶导数光谱图及二维相关光谱图,可以准确、快速地鉴别杜仲不同炮制品配方颗粒。  相似文献   
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