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The purpose of this study is to investigate the effect of standard fire on the strength and microstructure properties of concrete with different strength grades.

Different strength grades of concrete used for the investigation are M20, M30, M40 and M50. An electrical bogie hearth furnace was developed to simulate the International Standards Organization 834 standard fire curve.Concrete samples were subjected to high temperatures of 925, 1,029, 1,090 and 1,133°C for the duration of 1, 2, 3 and 4 h, respectively, as per standard fire curve. Compressive strength, tensile strength, thermal crack pattern and spalling of heated concrete specimens were evaluated by experimental investigation. Scanning electron microscopy and thermo-gravimetric analysis were performed to investigate the microstructure properties of heated concrete specimens.

Test results indicated reduction in the strength and changes in the microstructure properties of concrete exposed to elevated temperature. The degree of weight and the strength loss were found to be higher for concrete with higher grades. An empirical relation is proposed to determine the residual strength of concrete with different strength grade using regression analysis.

Results of this research will be useful for the design engineers to understand the behavior of concrete exposed to elevated temperature as per standard fire.

When concrete is exposed to elevated temperature, its internal microstructure changes, thereby strength and durability of concrete deteriorates. The performance of concrete with different strength grade exposed to standard fire is well understood. This research’s findings will be useful for the designers to understand more about fire resistance of concrete. A simple relationship is proposed to determine the residual strength of concrete exposed to various durations of heating.

The main targets of the work are analysis and simulation of flying laboratory performance. In particular, synthesis of control system for handling qualities change and evaluation in flight are taken into consideration.

Modification of handling qualities is obtained by applying indirect flight control system (FBW). The properties of the optimal controller are calculated through the indirect (implicit) model‐following method. In particular, the modified version based on the computer simulations is used.

Calculation and simulation concern the synthesis of desired handling qualities of the general aviation aircraft PZL‐M20 “Mewa” equipped with indirect (FBW) experimental flight control system. Results of the simulation show that the flying laboratory has the same properties as modeled aircraft, and it is possible to say that handling properties concern attitude orientation of the experimental aircraft is similar to modeled commuter aircraft.

The result of research can be implemented on a project of the flying laboratory based on general aviation aircraft PZL M20 “Mewa”.

The paper presents the practical approach for synthesis of the “Simplified total in flight simulator” performance which can be used for analysis of handling qualities of general aviation aircraft equipped with FBW. Research of this type focuses on military and transport airplanes however, there are no published works in the area of small aircraft so far.

Examines the economic effects of the channel tunnel link on two towns in Kent most likely to benefit from improved communications: Maidstone and Ashford. Concludes that both towns stand to gain economically as confidence in the tunnel grows and Kent becomes an accepted business location, mainly because of the strategic advantages of their location between the M25 and the continent.

In this paper, the suboptimal algorithm of adaptive control system is presented, which is specially adjusted for automatic flight control systems of general aviation and commuter aircraft, and unmanned aircraft (UMA) that conduct flights in atmospheric turbulence. At first, the method could be applied for correcting these changes in flight dynamics parameters, which cannot be compensated with the aid of an open adaptation loop. At the same time, full identification of aircraft model in real time is not required. This method is based on the estimation of most typical parameters of the aircraft mathematical model, which are most closely related to parameters, which are unmeasurable during flight, like aircraft real mass and position of center of gravity. The structure of an adaptation algorithm of aircraft flight control laws is based on the expert knowledge in the field of flight dynamics and is the result of optimization calculations. The examples which show attaining better flight comfort of the PZL M20, “Mewa” general aviation aircraft and quality improvement of the UMA, “Vector” pitch angle automatic control, have been presented.

In structural fire engineering, the importance of bolt assemblies is often overlooked. Connection design uses the temperature-dependent bolt strength-reduction factors prescribed in Eurocode 3, despite the existence of two distinct failure modes under tension; necking of the bolt shank, and thread-stripping. While literature exists to predict failure modes at ambient temperature, there is no method for failure mode prediction for elevated temperatures where ductility is critical to avoid collapse. Galvanised M20 structural bolt assemblies and bolt material from a single batch have been tested under tension at a range of temperatures and strain-rates typical of those experienced in fire. Turned-down bolt test data produced stress-strain curves characteristic of different microstructures at ambient temperature, despite a tempered-martensitic microstructure being specified in the standards. The failure modes of bolt assemblies were found to be dependent on the as-received microstructure at ambient temperature. At elevated temperatures, however, only thread-stripping was observed.

Concrete is subjected to elevated temperature for short duration, long duration and cyclic heating on many occasions. The dramatic fire accidents/incidents have renewed the interest in the area of research on concrete subjected to elevated temperature. From the literature review it is found that the experimental data which simulate the conditions of structural elements in stressed conditions when exposed to fire are scarce. The work presents a study on the residual characteristics of R.C. beams subjected to elevated temperature under unstressed and stressed conditions. The R.C beams were of size 120mm×120mm×1500mm and designed with single and double reinforcement and referenced as Type I and Type II respectively. M20 grade of concrete was used in casting the beams. The temperatures were kept as 100°C, 200°C, 300°C, 400°C and 500°C and the duration of exposure was 4 hours. The specimens were cooled in air and the residual properties were tested by conducting two point bending test on R.C. beams and their behavioral parameters were studied in comparison with beams tested under normal (room) temperature conditions. The extent of damage suffered measured by the damage factor was about 32 % for Type I beams and about 48% for the Type II beams tested under unstressed test condition when exposed to 500°C; whereas it is to an extent of 33% for Type I beams and 49% for Type II beams in stressed test condition for the same exposed temperature. The degradation in initial stiffness was nearly 57% and 49% for Type I and Type II beams in unstressed test and 54% and 73% respectively for stressed test when exposed to 500°C. The degradation in stiffness at 50% of ultimate load was nearly 36% and 35% for Type I and Type II beams in unstressed test and 49% and 76.6% respectively for stressed test when exposed to 500°C. The ultimate load of R.C. beams tested in stressed condition were marginally 5% lower than the beams under unstressed test condition.

Microcomputers are rapidly becoming commonplace in libraries today and will become even more so as prices fall and capabilities increase. Microcomputers can provide a wide range of services, from being an integral part of a circulation system to serving as terminals to access online databases and information utilities such as the Source or CompuServe. Software can be purchased or developed to assist in online literature searching (record keeping or standardization of database commands). Database packages, or even word processing programs, can be used to help compile local newspaper indexes or other local information files. Statistical packages can be used to analyze library usage. Even the laborious task of writing reports or letters can be greatly aided by word processing programs. Even though the availability of software is a determining factor in choosing a microcomputer, this paper will concentrate on meeting the hardware needs of individual libraries.

The purpose of this paper is to explore self-management among informal tourism employees in urban China with the theoretical basis of Jianghu and reveal the forming process and operation mechanism of China’s urban informal organizations’ self-management.

This paper adopts process–event analysis of informal tourism photographers surrounding Guangzhou Tower. Conducting field inspection and in-depth interviews, the forming process is analyzed and typical events are captured to unveil this self-management mechanism.

The self-management of informal tourism employees in China is based on the Jianghu theory, which specifies the role, obligation and responsibility of a member. These above rely on word-of-mouth order or implicit ways to treat newcomers, realize internal communication and deal with public affairs. Brotherhood, benevolence and etiquette make up the core values of the Jianghu theory that advises strategies in dealing with different events. This self-management, based on the Jianghu theory, has not only effectively solved internal conflicts, but has also achieved the goal of social management.

Informal employees’ self-management is extremely important due to the high cost of government intervention. Through China’s urban informal tourism employees’ Jianghu-styled self-management, the paper shows that the government should not crack down on this group indiscriminately. Instead, it should, through the management agent, set up effective Jianghu rules to realize regular control over this group.