, but this code // executes before the first paint, when

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is not yet present. The // classes are added to so styling immediately reflects the current // toolbar state. The classes are removed after the toolbar completes // initialization. const classesToAdd = ['toolbar-loading', 'toolbar-anti-flicker']; if (toolbarState) { const { orientation, hasActiveTab, isFixed, activeTray, activeTabId, isOriented, userButtonMinWidth } = toolbarState; classesToAdd.push( orientation ? `toolbar-` + orientation + `` : 'toolbar-horizontal', ); if (hasActiveTab !== false) { classesToAdd.push('toolbar-tray-open'); } if (isFixed) { classesToAdd.push('toolbar-fixed'); } if (isOriented) { classesToAdd.push('toolbar-oriented'); } if (activeTray) { // These styles are added so the active tab/tray styles are present // immediately instead of "flickering" on as the toolbar initializes. In // instances where a tray is lazy loaded, these styles facilitate the // lazy loaded tray appearing gracefully and without reflow. const styleContent = ` .toolbar-loading #` + activeTabId + ` { background-image: linear-gradient(rgba(255, 255, 255, 0.25) 20%, transparent 200%); } .toolbar-loading #` + activeTabId + `-tray { display: block; box-shadow: -1px 0 5px 2px rgb(0 0 0 / 33%); border-right: 1px solid #aaa; background-color: #f5f5f5; z-index: 0; } .toolbar-loading.toolbar-vertical.toolbar-tray-open #` + activeTabId + `-tray { width: 15rem; height: 100vh; } .toolbar-loading.toolbar-horizontal :not(#` + activeTray + `) > .toolbar-lining {opacity: 0}`; const style = document.createElement('style'); style.textContent = styleContent; style.setAttribute('data-toolbar-anti-flicker-loading', true); document.querySelector('head').appendChild(style); if (userButtonMinWidth) { const userButtonStyle = document.createElement('style'); userButtonStyle.textContent = `#toolbar-item-user {min-width: ` + userButtonMinWidth +`px;}` document.querySelector('head').appendChild(userButtonStyle); } } } document.querySelector('html').classList.add(...classesToAdd); })(); Honoring Van Baak - News & Stories | 黄大仙高手论坛

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Calvin News

Honoring Van Baak

Tue, Apr 29, 2003
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Calvin College physics professor David Van Baak is the 2003 winner of a Physics Education Distinguished Service Award.
The award is presented annually "in recognition of dedication and significant contributions to physics education" by the Michigan Section of the American Association of Physics Teachers (MIAAPT).
Interestingly the MIAAPT award program is sponsored by Ann Arbor-based Arbor Scientific, Inc. That company makes a variety of physics-education equipment, including a spectrum demonstration kit that Van Baak invented for a talk he once gave at an MIAAPT meeting.
The kit, which sells for $19 and is described by Van Baak as "very simple but visually pleasing," allows physics teachers to use their overhead projector to project a broad, bright spectrum of light onto a classroom wall. It includes color filters to show color addition and subtraction and an "anti-slit" mask to show complementary colors. Folks at Arbor Scientific say the kit is selling well and that teachers appreciate its clear instructions and its bright colors.
Van Baak is known across the state for his work in physics education.
"David has regularly made presentations at meetings (of the MIAAPT)," says Paul Zitzewitz of the University of Michigan at Dearborn. "These presentations are models of innovation and elegance and have been appreciated by teachers in high schools, community colleges and universities."