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Privacy concerns can prohibit research access to large-scale commercial query logs. Here we focus on generation of a synthetic log from a publicly available dataset, suitable for evaluation of query auto completion (QAC) systems. The synthetic log contains plausible string sequences reflecting how users enter their queries in a QAC interface. Properties that would influence experimental outcomes are compared between a synthetic log and a real QAC log through a set of side-byside experiments, and confirm the applicability of the generated log for benchmarking the performance of QAC methods.

Drawing is said to be the language of Engineers. In a simple drawing, we could depict what would require a thousand words to describe. No wonder why the technocrats always love to present their case with the aid of sketches and drawings. In the olden days, technical concepts and ideas were transformed into paper using pencils and erasers and the media was tracing paper. It had the inherent disadvantage that pencil writings were getting smudged or erased with the passage of time and the tracing paper was getting torn or damaged. Gradually, the pencil leads gave way to ink; so also, the tracing paper was replaced with tracing films. Stencils with suitable size pens and drawing instruments like set squares, protractor, compass. French curve & dividers gradually became the order of the day. Drawing boards with fancy Tee squares started decorating the drafting offices. Quality improvements came to the fore, not just in presentation; but in productivity and storage of drawings. During the Industrial Revolution, draftsmanship gradually became a specialized trade and drawing tables were considered an integral part of a Design or Engineering office. In those days, they were made of fine wood and brass; but slowly became more utilitarian and were built of steel and plastic.

Process systems are complex structures involving interaction of many components of diverse nature including humans. They are designed and built based on certain specifications and operated for many years. During the course of operation it may see several changes. Any change will have an impact on the operation of the plant. Management Of Change (MOC) is about understanding such changes and trying to control them. In the course of time companies have developed procedures and methods to implement changes so that they are controlled and its effects predictable. History is full of cases that resulted in accidents when such changes were made without adequate analysis. The paper will examine the basics of current MOC procedures and methods. While they address the particular part or the subunit where the changes are planned, its effect on the overall process system is usually forgotten. Case studies indicate that while everything appeared fine by conventional MOC procedures, the changes did impact the system in a manner not predicted by these procedures. Many MOC methods cannot assess or predict such impacts simply because it is incapable of doing so. A Systems approach would have predicted such impacts. Such an approach observes the changes as part of a whole system and in helps in understanding how changes can impact elsewhere on a long term basis. In conclusion the paper will demonstrate that Systems approach will be highly beneficial and can be built into existing MOC practices. To support the same several hindsight reviews of incidents will be presented; incidents which could have been addressed properly, had a Systems approach been taken at the right point of time. Introduction Management of Change procedures and methods evolved as companies felt the need to understand and control changes that were being made in the Oil and Gas production facilities. Oil and Gas facilities have become increasingly complex involving machinery and equipment along with different organizational units and many hundreds of people. The starting point of a formalized Management Of Change (MOC) can be thought of as the Lord Cullen report on Piper Alpha offshore platform incident (1990) which brought out several path breaking procedures on safety. Typical MOC procedures include checklists, forms and other documentation that are filled in by the relevant personnel and routed for approvals at different levels. However it has been noticed that these procedures sometime miss the impact of changes on the overall system usually on a long term basis. A systems approach is beneficial in this context because such an approach considers the process facility as a whole and helps in visualizing the changes and its impacts elsewhere in the system. Current MOC practices The authorization/approval procedures for any change in processing facility are defined by ‘Management Of Change’ policy of the company. The policy defines the specific review and authorization requirements and the procedures through which they are obtained, ensure that the changes do not introduce unacceptable risk. The policy usually provides the following:Definition of what constitutes a changeDocumentation of the proposed facility or operational changeIndependent design review of potential safety, health and environmental impactsPhysical inspection to ensure readiness of facilities and personal prior to start upResolution of safety, health and environmental concern generated during all stages of reviewTiered approval system in which level of management approval is required is dependent upon level of risk