Revitalizing disaster management

It seems every story about Indonesia recently involves a disaster. With alarming speed, we have replaced such countries as the Philippines, Nepal and Bangladesh as the most disaster-prone nation in the world. Indonesia, however, is not alone in facing natural disasters. Globally, the number of environmental calamities is rising, mostly owing to an increase in floods.

For the period of 1994-2003, the International Council for Science found floods were the most common natural hazard, making up 33 percent of disasters. Storms were next at 23 percent, epidemics at 15.2 percent, droughts at 15 percent and earthquakes at 7 percent. The remaining disasters included tsunamis, landslides and volcanic eruptions. Hazards related to extreme weather conditions occurred most frequently and often affected the largest areas.

In disaster science, the paradigm is now shifting from knowing that rivers flood to understanding how a flood can cause so much damage. Human beings, not nature, are the cause of disaster losses. It is unrealistic to think that we can engineer the earth to stop disasters, but it is possible to adjust human behavior to reduce their risk.

Indonesia has long recognized the importance of having a disaster management organization....

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Dynamic characteristics of a curved cable-stayed bridge

An assessment of dynamic characteristics of the 455 m Katsushika–Harp curved cable-stayed bridge is presented. Dynamics characteristics such as natural frequencies, mode shapes and modal damping ratios are obtained from seismic response of the bridge by employing a time-domain multi-input multi-output (MIMO) system identification (SI) technique. The technique makes use of base motions and superstructure accelerations as pairs of inputs–outputs to realize the coefficients of state-space system matrices. The SI results indicate the occurrence of many closely spaced modal frequencies with spatially complicated mode shapes. Fourteen global modes in the ranges of 0.45–2.5 Hz were identified, in which the girder motion dominated most of the modes. The tower modes were associated with girder modes and were characterized by the lowly-damped motion. Using identification results from six earthquakes, the effects of earthquake amplitude on modal damping ratios were observed.

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Laser Doppler Vibrometer for Damage Detection

The paper presents a study on the application of a laser Doppler vibrometer (LDV) for structural health monitoring using ambient vibration. The work covers three important issues namely, data acquisition, system identification, and structural damage detection. A two-laser system is employed for data acquisition using ambient response of the structure. Modal parameters are estimated by the eigensystem realization algorithm, after first deriving the impulse response functions from both laser responses using the Natural Excitation Technique.

In damage detection, a new matrix-updating-based method is proposed. The essential feature of this method is the non-iterative solving technique of inverse problem, which allows damage to be located and quantified by employing the modal parameters obtained before and after damage. Numerical simulation and laboratory-scaled experiments using bolted lap joint plate demonstrate that the proposed technique can detect locations and magnitude of damage with incomplete modal information.

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Entrepreneurial universities marry invention, profit

In the spirit of the slogan "2006, The Indonesian Year for Science", it worth asking the question how much our scientific communities have contributed to the economy. With the current 0.3 percent of national GDP invested in research and technology, some might argue that it is too soon to ask for such a contribution.

But while increasing national investment in research is vital, it is also essential to measure how much economic growth has -- and will -- emanate from these knowledge investments. New strategies should be developed to avoid the pitfall of the so-called "European paradox"; the conjecture that while European countries have consistently been leading players with top levels of scientific output, they lag behind in the ability to convert this knowledge into wealth-generating power.

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Living with and learning from earthquake

The two major earthquakes that have struck Indonesia recently caused damage beyond imagination. In 2004 the Aceh earthquake triggered the largest tsunami in modern history. Last month's quake in Yogyakarta may be not as huge in magnitude as other great historic earthquakes, but the area affected was extensive. The casualties from these two disasters were staggering, and this should remind everyone how earthquake-prone Indonesia is.

Since the devastating San Francisco earthquake of 1906, anti-earthquake engineering techniques have continuously improved...

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Minimizing the danger, damage of landslides


Every year during the rainy season landslides pose a serious threat to many who live in mountainous areas of Java, Sumatra and several other islands. This year, we have already witnessed two tragic disasters caused by large scale landslides. Heavy rainfall combined with the misuse of land has triggered massive gravitational movements of debris and mud.

The recent toll from the landslides in Jember and Banjarnegara were particularly severe and tragic. However, even though these types of disaster continue to increase in terms of frequency and seriousness, little has been done to prevent, or even, mitigate the possibility.

There is a tendency to focus only on addressing immediate problems rather than anticipating new ones. To make matters worse, many people still merely put this disaster down to an "Act of God", while in fact prevention of the landslide hazard is both scientifically possible and feasible.

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Making Earthquake Records Useful


Most people view earthquakes as horrific events. However, with new instrumentation techniques and mathematical modeling, records from seismic events can be utilized for the benefit of structural monitoring. Implementation of this would facilitate structural inspection and assessment for overall seismic safety againts future earthquake. complete article