Large-Scale Integration of Wind Generation Including Network Temporal Security Analysis

This paper presents a methodology to assess large-scale wind generation projects that considers their effect on network security. The proposed method is based on contingency analysis, including temporal study. Inputs to the simulation are grid model, forecasted load, conventional generation profiles, and wind variability of proposed projects. A time-step simulation is run for the time horizon to produce benefit indices for every location (bus) in the system. The congested transmission elements that require expansion are identified and ranked as part of the simulation. Each wind project in the proposed portfolio can result in benefits or costs for grid security. Policy makers can then use the method to design policies that ensure preservation of long-term system security. Developers could use the tool to identify security effects and assess their wind portfolios. Measuring network security and determining benefits of large-scale wind projects is a complex planning task that involves several aspects: temporal wind variability, spatial distribution of flows, multiple load and generation profiles, and numerous possible contingencies. All these wind project development aspects must be isolated to identify and correctly assign security costs and benefits     

Counseling patients to quit smoking. What to say, when to say it, and how to use your time to advantage

Helping patients stop smoking is one of the most important--and frustrating--services primary care physicians can provide. Many physicians are reluctant to spend time talking about tobacco use with patients who show little or no interest in changing their habits. Fortunately, specific technique have been identified that can make the task easier. This article from the distinguished Nicotine Dependence Center of the Mayo Clinic looks at the "best practices" for dealing with nicotine dependence.     

具有力传感器的纳米加工探针的设计

给出了一种用于复杂表面形状精密纳米加工的探针装置．该探针由一个高速可控的金刚石切割单元（FTC单元）和一个高灵敏度的压电式力传感器组成．而FTC单元由一个单点金刚石切割工具和一个压电陶瓷晶体（PZT）驱动器构成．压电陶瓷晶体（PZT）驱动器可对与切削量相对应的金刚石工具的Z向位置进行高速控制,从而实现加工复杂表面形状的目的．加工中的切削力是反映切削进程的重要指标,可由联结于FTC单元的高灵敏度力传感器进行测量．比对了用于联结力传感器和FTC单元的两种设计方法．     

Retrograde iliofemoral endarterectomy facilitated by balloon angioplasty

PURPOSE: The purpose of this study was to explore the feasibility of iliofemoral endarterectomy performed through a single groin incision. METHODS: Thirty-two patients aged 34 to 75 years (mean age 63.4 years) with a male/female ratio of 20:12 underwent 36 lower extremity inflow reconstructions from July 1989 to September 1994. Surgical indications were for limb-threatening ischemia in 24 patients and for claudication in eight patients. The procedures were done for occlusive disease of the external iliac artery and common femoral artery with patients under either spinal (n = 24) or local (n = 12) anesthesia. Intraoperative balloon angioplasty with fluoroscopic guidance preceded open retrograde iliofemoral endarterectomy. Adjunctive procedures included 18 profundaplasties, eight femorofemoral, nine femoropopliteal, and one femorotibial bypasses. RESULTS: Thirty-three of the 36 cases were initially successful. The three failures were in patients with extensive calcification. The mean follow-up has been 36.4 months, and the patency rate was 80.5% at 3 and 4 years. The four failures noted on follow-up were caused by three common iliac artery stenoses and one iliac system occlusion. The former group was successfully treated with balloon angioplasty/stent, and the latter patient required an aortofemoral bypass. No operative deaths or limb loss occurred in this series. CONCLUSIONS: Retrograde iliofemoral endarterectomy facilitated by balloon angioplasty is a safe, easy-to-perform, and viable option for patients with combined external iliac artery and common femoral artery occlusive disease. Midterm results (36.4 months) are favorable, and most hemodynamic failures are easy to correct with standard endovascular techniques.     

Collocation and galerkin finite element methods for viscoelastic fluid flow—II. Die swell problems with a free surface

The die swell problem occurs when a fluid flows down a capillary and is emitted into a gas which exerts negligible shear and normal forces on the jet. The die swell problem is solved for Newtonian and viscoelastic fluids. The viscoelastic fluids use a nonlinear Maxwell model but we report calculations for only a small elastic component. Both Galerkin and collocation Finite Element Methods are used and compared. The role of natural boundary conditions in the Galerkin method is compared to the pointwise satisfaction of boundary conditions in the collocation method.     

Induced ocular pseudopemphigoid

Two patients with a clinical picture identical to idiopathic ocular cicatricial pemphigoid had received long-term (six to nine years) echothiophate iodide treatment for control of glaucoma in the affected eyes after cataract extraction. Basement membrane zone staining for IgG was seen in the conjunctiva of one affected eye. Decreased or absent goblet cells, epidermalization of the conjunctiva, fibroses, and abnormal numbers of inflammatory cells were seen in both affected eyes.     

Using mobile telephones: cognitive workload and attention resource allocation

Driver distraction is recognized as being one of the central causes of road traffic incidents and mobile telephones are tangible devices (among many other electronic devices) that can distract the driver through changes in workload. Forty participants completed a motorway route characterized by a low level of road complexity in the form of vehicle handling and information processing. A peripheral detection task (PDT) was employed to gauge mental workload. We compared effects of conversation type (simple versus complex) and telephone mode (hands-free versus handheld) to baseline conditions. The participants' reaction times increased significantly when conversing but no benefit of hands-free units over handheld units on rural roads/motorways were found. Thus, in regard to mobile telephones, the content of the conversation was far more important for driving and driver distraction than the type of telephone when driving on a motorway or similar type of road. The more difficult and complex the conversation, the greater the possible negative effect on driver distraction.     

Intestinal passage of microencapsulated fish oil in rats following oral administration

Fish oil labelled with [(14)C-linolenin] tracer was orally administered by gavage as an oil-water mixture (free oil) or as an oil-in-water emulsion formulation (microencapsulated oil) to fasted rats. Groups of rats were then given food after gavage or alternatively not fed to examine the effect of food on intestinal passage. Feeding after gavage drives lumenal free oil faster through the gastrointestinal (GI) tract. Microencapsulation slows down the lumenal progression in the GI tract with feeding. Non-feeding also slows down the lumenal progress of free oil in the GI tract but this is not influenced by microencapsulation. Analysis of the relative distribution of the label along the GI tract tissue wall showed that the upper small intestine was the main site of label accumulation in the GI tract. Of the oil that remained in the lumen, there was slight protection against early uptake and metabolism in the stomach and upper GI tract in rats that were either fed or not fed after dosing when microencapsulated oil was administered. Microencapsulation increased the levels of radiolabel in the liver and blood. The primary organ for accumulation of radiolabel for both free and microencapsulated oils in rats that were fed or fasted after dosing was the liver.