Cooperation, competition and the longevity of stakes in joint ventures: A value creation approach

This research used a transaction value perspective (Zajac and Olsen, 1993; Madhok and Tallman, 1998) to examine the impact of competitive and cooperative forces on joint venture (JV) duration. We argue that some factors increasing the management cost of the JV may also increase its value potential. Such factors include whether the partners are direct competitors, and whether their nationality is the same. Findings from a survey study provided support for all of our hypothesesCooperation; joint ventures; competition;

More than two are a crowd. Different paths to effectiveness in dyadic and multi-party joint ventures

Using data from 87 joint venture (JV) experiences, we compared the effectiveness of dyadic and multi-party JVs. We show that dyadic JVs are more effective than multi-party ones, and that the conditions resulting in an enhanced effectiveness differ for the two groups: while relational embeddedness significantly influences the effectiveness of dyadic JVs, monitoring mechanisms are pivotal in the case of multi-party JVs.joint venture;

System-level design and RF front-end implementation for a 3-10ghz multiband-ofdm ultrawideband receiver and built-in testing techniques for analog and rf integrated circuits

This work consists of two main parts: a) Design of a 3-10GHz UltraWideBand (UWB) Receiver and b) Built-In Testing Techniques (BIT) for Analog and RF circuits. The MultiBand OFDM (MB-OFDM) proposal for UWB communications has received significant attention for the implementation of very high data rate (up to 480Mb/s) wireless devices. A wideband LNA with a tunable notch filter, a downconversion quadrature mixer, and the overall radio system-level design are proposed for an 11-band 3.4-10.3GHz direct conversion receiver for MB-OFDM UWB implemented in a 0.25mm BiCMOS process. The packaged IC includes an RF front-end with interference rejection at 5.25GHz, a frequency synthesizer generating 11 carrier tones in quadrature with fast hopping, and a linear phase baseband section with 42dB of gain programmability. The receiver IC mounted on a FR-4 substrate provides a maximum gain of 67-78dB and NF of 5-10dB across all bands while consuming 114mA from a 2.5V supply. Two BIT techniques for analog and RF circuits are developed. The goal is to reduce the test cost by reducing the use of analog instrumentation. An integrated frequency response characterization system with a digital interface is proposed to test the magnitude and phase responses at different nodes of an analog circuit. A complete prototype in CMOS 0.35mm technology employs only 0.3mm2 of area. Its operation is demonstrated by performing frequency response measurements in a range of 1 to 130MHz on 2 analog filters integrated on the same chip. A very compact CMOS RF RMS Detector and a methodology for its use in the built-in measurement of the gain and 1dB compression point of RF circuits are proposed to address the problem of on-chip testing at RF frequencies. The proposed device generates a DC voltage proportional to the RMS voltage amplitude of an RF signal. A design in CMOS 0.35mm technology presents and input capacitance <15fF and occupies and area of 0.03mm2. The application of these two techniques in combination with a loop-back test architecture significantly enhances the testability of a wireless transceiver system

Dual Gate Graphene FETs with fT of 50 GHz

A dual-gate graphene field-effect transistors is presented, which shows improved RF performance by reducing the access resistance using electrostatic doping. With a carrier mobility of 2700 cm2/Vs, a cutoff frequency of 50 GHz is demonstrated in a 350-nm gate length device. This fT value is the highest frequency reported to date for any graphene transistor, and it also exceeds that of Si MOSFETs at the same gate length, illustrating the potential of graphene for RF applications

Operation of Graphene Transistors at GHz Frequencies

Top-gated graphene transistors operating at high frequencies (GHz) have been fabricated and their characteristics analyzed. The measured intrinsic current gain shows an ideal 1/f frequency dependence, indicating an FET-like behavior for graphene transistors. The cutoff frequency fT is found to be proportional to the dc transconductance gm of the device. The peak fT increases with a reduced gate length, and fT as high as 26 GHz is measured for a graphene transistor with a gate length of 150 nm. The work represents a significant step towards the realization of graphene-based electronics for high-frequency applications

PREÇOS DA TERRA NO BRASIL

Este trabalho analisa o preço da terra no período 1975 a 2006, mas ocupa-se principalmente com o período mais recente, de 2000 a 2006. Para que o leitor tenha uma melhor dimensão dos preços de terras no Brasil, comparações serão realizadas com os preços de terras nos Estados Unidos em anos recentes. As principais fontes de informação são a Fundação Getúlio Vargas – FGV que fornece as informações sobre preço de venda de terras de lavouras, pastagens e preços de arrendamentos por estados, Regiões e Brasil e o Departamento de Agricultura dos Estados Unidos (USDA) que publica os preços de terras por regiões e estados. Complementarmente, são utilizadas outras fontes como a Secretaria da Agricultura e do Abastecimento do Paraná - Seab, através de seu Departamento de Economia Rural - Deral.-------------------------------------------------------------------- ----------------The paper analyses price land in Brazil during the 1975 – 2006 period. To best information, we compare prices in Brazil and in United States. We used the following information sources: Fundação Getúlio Vargas – FGV, that publishes price land and cash rents by state, region and Brazil. United States information are from United States Department of Agriculture - USDA. Another information source is Departamento de Economia Rural do estado do Paraná – Deral.Preço de Terra, Lavouras, Pastagens, Brasil, Price, Land, Crops, Pasture, Brazil, Land Economics/Use,

Analyzing the effects of a dynamic or static orthosis after radical nerve injury using the Nine-Hole Peg Test

Objective: The radial nerve is a commonly injured upper extremity peripheral nerve. The inability to extend the wrist results in the loss of hand function and dexterity that affects patients' ability to perform their activities of daily living. There is not strong evidence to support orthosis efficacy to improve dexterity. The purpose of this study was to evaluate whether a static or dynamic orthosis resulted in improved hand dexterity when assessed with the 9-HPT after radial nerve injury. Materials and Methods: Twenty three participants who suffered radial nerve palsy participated in the study. The test was repeated three times for each participant, first without the orthosis, and then wearing the static orthosis, and finally wearing the dynamic orthosis. The 9-HPT was used as the outcome measure. Results: The distribution of the 9-HPT times (sec) was of 35.7 ±4.9 without a wrist orthoses, and decreased with the use of the static and the dynamic orthoses to 33.7 ±4.8 (P<0.01) and 24.6 ±2.6) (P<0.01) respectively. Conclusions: The use of a dynamic orthosis after radial nerve palsy can provide the patient with greater manual dexterity when compared to the use of a static orthosis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

High Density en Route airspace safety level and colllision risk estimation based on stored aircraft tracks

The major constraint in developing appropriate monitoring methodologies and tools to assess the level of safety in en-route airspaces where controllers monitor air traffic by means of radar surveillance and provide aircraft with tactical instructions lies in the estimation of the operational risk. The operational risk estimate normally relies on incident reports provided by the air navigation service providers (ANSPs). The provision of incident reports is highly dependent on the safety management practices of each ANSP and requires the complete cooperation of both controllers (in identifying and reporting altitude deviations) and incident investigators (in providing operational reports to the RMA in good time). The EUROCONTROL 2009 SRC Annual Safety Report concludes that whilst "there has been an improvement in reporting of safety occurrences, overall progress towards full reporting by states is too slow." This paper presents a new and innovative approach to assessing aircraft safety level within En-route Airspaces based upon the process and analysis of radar tracks. The proposed methodology has been designed to complement the information collected in the accident and incident databases, thereby providing the following information inferred from the in depth assessment of proximate event

Abruptio placentae: morbimortalidad y resultados perinatales

El desprendimiento prematuro de placenta normoinserta (DPPNI) o «abruptio placentae» se define como la separación parcial o completa de una placenta normalmente adherida antes del parto o después de la semana 20 del embarazo. Ocurre en el 0.5-2% de todos los nacimientos, y de estos, el 50% de los casos se acompa˜na de embarazos con síndrome hipertensivo, puede causar morbilidad grave, como coagulación intravascular diseminada, insuficiencia renal, transfusiones masivas e histerectomía. Por lo regular todas las complicaciones maternas graves del DPPNI son consecuencia de la hipovolemia, y de la enfermedad de base asociada al desprendimiento. La tasa de mortalidad materna es aproximadamente del 1%1.Objetivo: Describir los resultados neonatales y las complicaciones maternas en pacientes que presentaron abruptio placentae en el HGO del IMIEM. Método: Se realizó un estudio retrospectivo, transversal y descriptivo. Resultados: La edad promedio del grupo de estudio estuvo entre 21 y 35 anos (61.6%), el 20.9% ˜ fueron mujeres mayores de 35 anos, el 17.4% menores de 20 años, el 33.7% eran primigestas y el 66.3% multigestas Entre los principales factores de riesgo el 34.6% presentó cuadros hipertensivos del embarazo, seguido por la rotura prematura de membranas con un 22.1%. De los síntomas que las llevaron al hospital, el sangrado transvaginal fue el predominante con un 25.6%, hipertonía uterina un 22.1-10.5% de las pacientes ingresaron sin cuadro clínico de desprendimiento prematuro de placenta normoinserta. Las complicaciones que se presentaron fueron: choque hipovolémico el 15.1%, útero de Couvelaire el 8.1%, atonía uterina el 5.8%, y el 69.8% de las pacientes evolucionaron sin complicaciones; al 1.2% se les realizó histerectomía obstétrica. La vía de nacimiento fue en su mayoría abdominal con un 97.7-2.3% por vía vaginal. La tasa de mortalidad perinatal fue del 10.5%, de esta el 8.1% fueron muertes fetales. Se reportaron 2 muertes maternas cuya causa directa de la muerte no fue el desprendimiento prematuro de placenta normoinserta sino complicaciones debidas a preeclampsia-eclampsia. Conclusiones: El abruptio placentae es una catástrofe obstétrica que conlleva un alto riesgo materno-fetal, el diagnóstico y la interrupción oportuna del embarazo disminuyen de forma importante la morbilidad perinatal

Ultrafast graphene photodetector

The electronic properties of graphene are unique and are attracting increased attention to this novel 2-dimensional system. Its photonic properties are not less impressive. For example, this single atomic layer absorbs through direct interband transitions a considerable fraction of the light (~2.3%) over a very a broad wavelength range. However, while applications in electronics are vigorously being pursued, photonic applications have not attracted as much attention. Here, we report on ultrafast photocurrent response measurements in graphene (single and few-layers) field-effect-transistors (FETs) up to 40 GHz light intensity modulation frequencies, using a 1.55 micron excitation laser. No photoresponse degradation is observable up to the highest measured frequency, demonstrating the feasibility and unique benefits of using graphene in photonics. Further analysis suggests that the intrinsic bandwidth of such graphene FET based photodetectors may exceed 500 GHz. Most notably, the generation and transport of the photo-carriers in such graphene photodetectors are fundamentally different from those in currently known semiconductor photodetectors, leading to a remarkably high bandwidth, zero source-drain bias (hence zero dark current) operation, and good internal quantum efficiency.Comment: 25 pages, 3 figure