Jolly Chen

Tioga-2: a direct manipulation database visualization environment

The paper reports on user experience with Tioga, a DBMS centric visualization tool developed at Berkeley. Based on this experience, we have designed Tioga-2 as a direct manipulation system that is more powerful and much easier to program. A detailed design of the revised system is presented, together with an extensive example of its application.

Zooming and tunneling in Tioga: supporting navigation in multidimensional space

The Tioga system applies a boxes and arrows programming notation to allow nonexpert users to graphically construct database applications. Users connect database procedures using a dataflow model. Browsers are used to visualize the resulting data. This paper describes extensions to the Tioga browser protocol. These extensions allow sophisticated, flight-simulator navigation through a multidimensional data space. This design also incorporates wormholes to allow tunneling between different multidimensional spaces. Wormholes are shown to be substantial generalizations of hyperlinks in a hypertext system. These powerful mechanisms for relating data provide users with great flexibility. For example, users can create magnifying glasses that provide an enhanced view of the underlying data.<<ETX>>

Advanced QFN Surface Mount Application Notes development

The advanced Quad Flat No-Lead (aQFN) package is an enhanced version of conventional QFN with multiple row terminals of featuring higher number of I/O ports. The aQFN thermal and electrical performance are superior due to smaller profile and shorter interconnects and the solder wettability control and board-level thermo-mechanical reliability are greatly enhanced over conventional QFN because of the higher package standoff. aQFN provides similar I/O number approaching that of a BGA-type chip-scale package (FBGA) but much less cost since the expensive substrate is replaced by lead frame. aQFN turns out to be an ideal low cost solution for electrical components of portable telecommunication applications such as IrDA, blue-tooth, RFID, cell phone baseband etc. for its superior thermal, electrical, reliability performances and miniaturized package size, With such advantages, the replacement of FBGA with aQFN in low up to medium lead-count applications is therefore highly expectable, especially for handheld & PDA devices with its related applications. With such higher pin-count, multi-row and small terminal pitch than QFN, how to design the aQFN package terminals for printed circuit board layout and the stencil patterning and opening for solder paste printing become crucial issues. aQFN will be introduced in terms of its application advantages, development, fabrication process flow, SMT process with stencil design guideline for surface mount assembly yield. Finally, “Surface Mount Application Notes” have been issued.

The Tioga-2 Database Visualization Environment

This paper reports on user experience with Tioga, a DBMS-centric visualization tool developed at Berkeley. Based on this experience, we have designed Tioga-2 as a direct manipulation system that is more powerful and much easier to program. We present a detailed design of the revised system together with an extensive example of its application. We also give a progress report on a Tioga-2 implementation.

Navigation and coordination primitives for multidimensional visual browsers

This paper describes extensions to the Tioga flight-simulator browsing protocol presented by Stonebraker et al. (1993a). These extensions allow users to navigate a multidimensional data space using sophisticated zooming capabilities. This design also allows users to move easily between different multidimensional spaces. Tunneling between different data spaces is shown to be a substantial generalization of hyperlinks in a hypermedia system. Finally, our design provides for the coordination of multiple browsers. This preserves context and allows users to explore multiple paths simultaneously.