IN THE PIPELINE: Making Waves In The Detection Field
Open a file cabinet drawer labeled "mines" and you'll find a dozen land mines. In a nearby desk drawer, untold numbers of termites crawl around in sealed plastic containers.
But don't worry, it's all in the name of scientific research. Donskoy, an engineering professor at Stevens Institute of Technology in Hoboken, N.J., uses the termites to refine one of his latest inventions, a device that detects the bugs in walls and other structures. Another project is a land-mine detector, which explains the mines in the file cabinet (minus the explosives, by the way).
The theme that ties Donskoy's inventions together is the use of waves to detect things. The termite-finder uses microwaves. Another device uses sound waves to detect cracks inside pipes and heavy equipment, which can help prevent catastrophic accidents.
"I specialize in the detection field, using different types of penetrating radiation, acoustics, microwaves, optical waves," said Donskoy, a Russian immigrant who sports a professorial mustache, glasses and blazer.
Donskoy is chief technology officer of Intelligent Sensing Technologies LLC, a company that's trying to market some of his inventions. He co-founded the company with partners whom he declined to identify.
The termite detector, Pestfinder, is now being tested in the field by pest-management vendors in New Jersey. The crack-detecting device, N-Scan, is also in testing stages.
Sending Waves After Pests
Donskoy has tackled land mines and pipeline cracks at Stevens, but something closer to home caught his eye in recent years: termites. In 2000, he bought a new house in Monmouth County, N.J. He was surprised that the home inspector used a fairly low-tech method to search for termites - a flashlight and a screwdriver.
Donskoy thought there must be a better way. The device he ultimately developed resembles a high-tech broom. The head has eight sensors that emit microwaves at safe, low levels. The waves can sense live insects by their moisture and motion, which triggers red lights on the head of the device. The lights pinpoint the location of the insect activity.
A pest control operator can scan for termites by moving Pestfinder up and down a wall and other structures, as if he were painting.
Donskoy began leasing the Pestfinder to New Jersey pest control operators in February for about $200 a month. The operators have been providing feedback to help Donskoy improve the product.
Jerry Smith , principal of Dial Pest Control in Caldwell, N.J., said Pestfinder is helpful. An inspection with Pestfinder is more thorough than an inspection using just a flashlight and a screwdriver, Smith said.
Also, Pestfinder allows pest control operators to pinpoint the location of termites. That allows for more targeted use of chemicals to kill the termites, Smith said. Pestfinder is also a useful tool to confirm that a home has been treated successfully.
"You can use Pestfinder to take the load and burden off inspectors," said Smith, who is also president of the New Jersey Pest Control Association, a trade group.
Pestfinder isn't the only high-tech termite detector on the market. Termatrac Pty. of Australia sells a handheld device that uses microwaves to sense termites. Jim Davies, general manager of Termatrac, said he began leasing the devices in Australia in 1999 and launched Termatrac in the U.S. in October 2001.
Termatrac has one microwave sensor. Donskoy noted that Pestfinder has eight sensors, which can cover a larger area. Also, if one of the sensors picks up termites, the operator can confirm the reading by moving other sensors over the site. Davies said he hasn't used Pestfinder and couldn't comment on the differences between it and Termatrac.
Making Land-Mine Detection Efficient
Donskoy sought to develop a new land-mine detection device because current methods - in combat and postwar - are inefficient, he said. Metal detectors and magnetometers produce a high number of false readings because it's hard to distinguish between actual mines and nonlethal pieces of metal, Donskoy said. Newer methods rely on imaging, but these can also produce false readings.
So Donskoy developed a device based on "nonlinear seismo-acoustic land mine detection." Mounted on a rolling tripod or a military vehicle, the device emits sound waves and seismic waves, which vibrate the soil and its contents. If a mine is present, it will cause a disturbance in the vibrations that is picked up by sensors.
The device can be programmed ahead of time to recognize specific disturbances caused by antipersonnel and antitank mines, Donskoy said. Ordinary objects in soil, such as rocks and plants, generally don't produce false readings because they are more rigid.
Donskoy's device was tested in the field by the U.S. Army in June 2001, he said. It confidently detected plastic antitank mines that were buried five inches below the surface. Plastic antipersonnel mines were detected at up to two inches. The device was "completely insensitive" to other objects, he said.
The land-mine detection system is still in development, Donskoy said. He expects more field tests to be conducted later this year.
A Brush With Imperfection
Donskoy has seen firsthand the effects of undetected flaws in critical equipment. In 1990, as the Cold War was winding down, Donskoy was a Soviet scientist aboard a research ship in the Barents Sea, north of Russia. His mission was to improve technology to detect American submarines.
But the mission was nearly wrecked when the ship's furnace ignited. The cause was a crack in a bolt on a fuel line, Donskoy said. The fire was brought under control and none of the 100 passengers was seriously injured.
Shortly after the fire, Donskoy defected from the U.S.S.R. The research vessel had docked in Germany, where Donskoy debarked and eventually made it to the West. He came to the U.S. in 1990 and is now an American citizen.
At Stevens, Donskoy began looking into the problem of flaws in infrastructure. Testing is especially important for military aircraft, nuclear power plants, oil and gas pipelines and chemical facilities.
Traditionally, visual inspections have been used to detect cracks. But visual inspections can't detect internal cracks in equipment.
N-Scan uses a combination of sound waves and vibration to detect internal cracks. Sensors connected to a laptop computer emit vibrations that cause tension and slightly stretch the object apart if any cracks are present. Ultrasonic waves can then sense the cracks.
Conventional ultrasound testing devices can miss cracks that are close to the surface, Donskoy said.
N-Scan is still in testing stages. It will probably cost in the "tens of thousands" when it becomes commercially available, Donskoy said.
Intelligent Sensing Technologies has sold its prototype N-Scan to Electricite de France (F.EDF), the state-owned energy company, Donskoy said. EDF engineer Jean-Louis Lottiaux said he has used N-Scan to detect cracks in pipes.
让物理波在探测领域大显身手
来到季米特里．东斯基(Dimitri Donskoy)的实验室附近你最好轻手轻脚。
因为如果打开实验室文件柜的抽屉，你会发现里面居然放著十几个地雷。附近的一个抽屉里面还有数不清的白蚁在密封的塑料容器里爬来爬去。
别害怕，这些东西只是用来做试验的。东斯基是位于新泽西州的史蒂文斯理工学院(Stevens Institute of Technology)的一位工程学教授。他在用白蚁来改进他的一项最新发明--一种能够探测墙壁和其他建筑物内部的虫子。另一项发明是地雷探测器，这可以解释为何文件柜内藏有地雷（顺便说一句，地雷里面的炸药已经被除去了）。
东斯基的所有发明都围绕著一个主题开展，那就是利用物理波来探测物体。白蚁探测仪利用的是微波。另一种仪器利用声波来探测管道和重型设备内部的裂缝，这样可以在灾难性事故发生前做到防患于未然。
东斯基称，他专门从事于探测领域，利用各种具有穿透力的放射线、声波、微波和光波来进行探测。东斯基是一位俄罗斯移民，他的大胡子、眼镜和夹克无不流露出一位学者的风范。
东斯基现在是Intelligent Sensing Technologies LLC的首席技术长，这家公司正尝试著推广他的一些发明。东斯基是公司的共同创始人之一，但他拒绝披露其他创始人的身份。
名为“Pestfinder“的白蚁探测仪正在由新泽西州的害虫防治供应商进行现场测试。同样，用于探测裂缝的仪器“N-Scan“也处于测试阶段。
利用物理波追踪害虫
东斯基已经在史蒂文斯理工学院解决了对地雷和管道裂缝的测试问题，但近几年来一个困扰著他家的问题--白蚁引起了他的关注。2000年，他买了一座位于新泽西州蒙贸斯县的房子。他惊讶地发现，当房屋验收员搜寻白蚁时使用的竟然是一种科技含量很低的方法--一个手电筒和一个扳手。
东斯基认为一定还有探测白蚁的更好办法。他最终发明了一种类似于扫除的高科技仪器。这种仪器的最前端配有8个传感器，能够发射符合安全标准的低辐射微波。微波能够通过活昆虫身上的水分和运动来对它们进行探测，因为白蚁产生的水分和运动能够促使低最前端的传感器发出红光。灯光能够对昆虫所处的位置进行定位。
害虫防治运营商在使用Pestfinder时只需像绘画一样上下扫描墙壁和其他建筑的表面，就能发现白蚁的位置。
今年2月份，东斯基开始把Pestfinder以每个月约200美元的价格租借给新泽西州的害虫防治运营商。然后，由运营商向东斯基提供反馈，以便于他对产品做出改进。
新泽西州的害虫防治运营商Dial Pest Control的主管杰瑞?史密斯(Jerry Smith)称，Pestfinder确实管用。史密斯称，与使用手电筒和扳手相比，Pestfinder在探测白蚁时更加全面彻底。
另外，害虫防治运营商还可以通过Pestfinder对白蚁的位置进行定位。史密斯称，这种功能的优势在于能够加大投放化学杀虫剂的准确度，从而提高灭虫率。此外，Pestfinder还能够帮助人们来确定是否已经成功地消灭了房屋里面的白蚁。
史密斯说，Pestfinder的横空出世减轻了房屋验收员的工作负担。史密斯还是新泽西州害虫防治协会(New Jersey Pest Control Association)的负责人。
不过，Pestfinder并不是目前市场上唯一的高科技白蚁探测产品。澳大利亚的Termatrac Pty也出售一种利用微波来检测白蚁的手持仪器。Termatrac的总经理吉姆?戴维斯(Jim Davies)表示，他于1999年开始在澳大利亚出租这种设备，并于2001年10月打入美国市场。
但Termatrac的产品只有一个微波传感器。东斯基指出，Pestfinder却有8个传感器，因此探测区域更加广泛。另外，如果其中的一个传感器探测到了白蚁，使用者可以用其余的传感器来验证探测结果。戴维斯表示，他尚未使用过Pestfinder，因此无法就两种产品之间的差异发表意见。
能够提高地雷探测的效率
东斯基称，他希望开发一种地雷探测仪器，因为用于战争和战后的现有探测方法效率低下。
东斯基称，金属和磁力探测器的误报率很高，因为它们难以准确分辨哪些是真正的地雷，而哪些是无关紧要的金属碎片。较为先进的方法依赖于成像技术，但基于这一技术的仪器同样也会真假不分。
因此东斯基开发出一种基于非线性地震波-声波地雷探测技术的仪器。这种仪器架设在一个旋转的三脚架或者军用车辆上，利用发出的声波和地震波使土壤和里面的物体发生震动。如果土壤里面有地雷就会使波形发生扭曲，传感器就会监测到这种情况。
东斯基称，如果事先为这种仪器设计了相应的程序，它还能辨别出由反步兵和反坦克地雷产生的特定扭曲信号。岩石、植物等土壤内的普通物体不会使波形扭曲，因为它们的质地更加坚硬。
2001年6月，美国陆军对东斯基的仪器进行了现场测试。它令人信服地探测到了埋藏在地表5英寸之深的反坦克地雷。它还能探测到地下2英寸之内的塑料反步兵地雷。而对于其他物体，这种仪器完全没有反应。
东斯基称，地雷探测系统仍在研发之中。他预计今年晚些时候将对其进行更多实地测试。
对于重要设备中未被发现的漏洞可能引发的灾害，东斯基有著切身的体会。1990年，当冷战接近尾声时，东斯基作为前苏联科学家登上了一艘驶往俄罗斯北部巴伦支海的考察船。他此行的使命是改进侦测美国潜艇的技术。
但当轮船的燃炉点火后，这项使命几乎毁于一旦。据东斯基透露，事故的原因很简单--燃油管路上的一个螺栓有裂缝。大火最终得到了控制，船上的100名船员没有人受到严重伤害。
在大火发生不久之后，东斯基逃离了前苏联。考察船停靠在德国港口时，东斯基离开了考察船。他于1990年到达美国，现已加入美国国籍。
在史蒂文斯理工学院，东斯基开始把探寻基础设施中的裂纹作为研究课题。测试对于军用飞机、核电厂、油气输送管道和化工设施来说尤为重要。
以往人们都是用目测的方法来检查是否存在裂缝。但视觉观察无法看到设备内部的裂缝。
N-Scan利用声波和震动的方式来检测物体内部的缝隙。与笔记本电脑连接的传感器产生震动，如果物体内部存在裂缝，那么震动就会使该物体感受到张力，导致物体长度出现轻微的延展。之后超声波就可以检测出裂缝。
东斯基称，常规的超声波检测仪器无法探测到接近物体表面的裂缝。
N-Scan仍处于测试阶段。东斯基称，或许只需花费数万美元就可以把这种仪器推向市场。
法国电力(Electricite de France, F.EDF)已经购买了一台N-Scan样机。法国电力的工程师让．路易斯(Jean-Louis Lottiaux)称，他用N-Scan检测出了管道内的裂缝。
