دانلود گزارش کارورزی و کار آموزی

چکیده : 

When designing clinical trials, researchers often encounter the uncertainty in the treatment effect or

variability assumptions. Hence the sample size calculation at the planning stage of a clinical trial may

also be questionable. Adjustment of the sample size during the mid-course of a clinical trial has become a

popular strategy lately. In this paper we propose a procedure for calculating additional sample size needed

based on conditional power, and adjusting the final-stage critical value to protect the overall type-I error

rate. Compared to other previous procedures, the proposed procedure uses the definition of the conditional

type-I error directly without appealing to an extra special function for it. It has better flexibility in setting

up interim decision rules and the final-stage test is a likelihood ratio test.

چکیده : 

This paper reports on the results of a case study that examines the effect of the contract

and accounting on inter-organisational trust in an international joint venture (IJV). The

empirical setting of the research was an IJV relation between a United Arab Emirates (UAE)

firm and its western partner. Data were gathered from multiple sources, including documents,

observations, interviews and discussions with managers. The paper aims to explore

the process of trust development and the role of the contract and accounting in this. We

find that trust developed differently for the partners. Moreover the trust concerns of the

partners were not the same. Based on this we conclude that trust was not automatically

reciprocated. Instead it needs relating to other items such as the contract, accounting and

also the institutional environment. The open-book accounting we observed could only be

termed ‘partial’ because the western partner had access to the local partner’s books but not

the vice versa. But this partial open-book accounting created conflicts between the partners.

We argue that developing one kind of trust through one particular medium may help

one party but may damage the relationship between the partners.

چکیده :

In scramble competition mating systems, individual behaviours related to maleemale competition are

expected to be plastic across sociosexual environments. However, the evolutionary forces that shape

individual differences in behavioural plasticity remain poorly understood. We measured behaviour

associated with scramble competition in male water striders, Tenagogerris euphrosyne, in two social

contexts. Male T. euphrosyne tend to mount other individuals or pairs indiscriminately and then

dismount if their target is either another male or a mating pair. We measured the speed with which a

focal male dismounted (i.e. his sensitivity to having made an inappropriate mounting) in each of these

contexts. We quantified temporal consistency of dismount speed within each context, as well as individual

variation in behavioural plasticity across contexts. We then estimated the effect of the behaviour

and of plasticity on individual fitness in different sex ratio conditions. We found that individuals differed

in their recognition sensitivity traits, and also in how plastic their sensitivity (i.e. dismount speed) was to

context (mating status or sex). When we measured the mating success of each male within experimental

groups kept at four different sex ratios, recognition sensitivity traits in both contexts interacted to

influence mating success, and there were significant differences in linear selection on sensitivity traits

between sex ratio treatments. We discuss how insensitive males evolve, and how individual variation in

behavioural plasticity could be maintained by selection or environmental variability.