• Journal of Chest Surgery
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• v.11 no.1
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• pp.97-101
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• 1978

Primary cyst of the diaphragm is a rather uncommon disease. This is a report of a case of diaphragmatic cyst, located in the tendinous portion of the right diaphragm. The patient had no specific symptoms in the respiratory systems, but suffered from gastrointestinal symptoms [indigestion, epigastralgia, and loss of appetite etc.] for 2 months. Accidentally, on a simple chest x-ray examination, a round homogenous mass density was discovered. Tomography showed a well circumscribed parenchymatous mass. So a coin lesion in the medial segment of the right lower lobe was suspected. A thoracotomy was performed. There were no pathological findings in the lung and pleura. A ping-pong ball sized round mass, which was soft, elastic and fluctuated,was noted in the tendinous portion of the diaphragm. It was enucleated completely without diaphragmatic rupture, and diagnosed as a primary diaphragmatic cyst [fibrous-walled] by the histopathologic examination. Postoperative course was uneventful.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.5
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• pp.63-68
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• 1998

The absolute pressure sensor using SDB wafer has been fabricated. the structure of the sensor consists of two wheatstone bridges and a diaphragm. One of the two wheatstone bridges is located on the edge of diaphragm, and the other is located on the center of diaphragm. The diaphragm cavity is sealted in vacuum (~10$^{5}$ Torr) to reduce the effect of temperature due to the vapor in the cavity on the sensitivity of pressure sensor. This is the minor method of temperature compensation method. In this experiment the main compensation method is to use the difference of the two bridge offset voltages. The drift of offset voltage with temperature is reduced by using this method so that temperature charcteristics is improved. In this method the temperature effect in the range of 22~100.deg. C was compensated over 80%.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.188-191
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• 1993

Silicon flow sensor which can detect the magnitude and direction of two dimensional air flow was designed and fabricated by CMOS process and bulk micromachining technique. The flow sensor consists of three-layered dielectric diaphragm a heater at the center of the diaphragm and four thermopiles surrounding the heater at each side of diaphragm as sensing elements. This diaphragm structure contributes to improve the sensitivity due to excellent thermal isolation property of dielectric materials and its tiny thickness. The flow sensor has good axial symmetry to sense 2-D air flow with the optimized sensing position in the given structure. Measured sensitivity of our sensor is $18.7mV/(m/s)^{1/2}$.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.28-35
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• 2007

Currently, most of all valves using at the semiconductor & LCD manufacturing process are packless type. Such valves are needed to have the functions to protect perfectly from the leakage of fluid by using bellows and diaphragm instead of the grand packing. But not only those valves made in Korea are not available at this point, but also advanced foreign manufacturers do not open enough their data on the basic technology. Otherwise although they open the data a little, they are almost data about stainless steel for pneumatic valves. In this paper, it was focused on the fluid valves for chemical & DI water based on the data of steel valves which are already using commercially. And also this study concentrated to collect the basic developing data of Eco-On/Off diaphragm valve by ourselves.

• Journal of Sensor Science and Technology
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• v.16 no.3
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• pp.174-178
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• 2007

This paper presents a novel, highly sensitive condenser microphone with a flexure hinge diaphragm. We used the finite-element analysis (FEA) to evaluate the mechanical and acoustic performance of the condenser microphone with a hinge diaphragm. And we fabricated the miniature condenser microphones with area of 1.5 mm${\times}$1.5 mm. From the simulation results, we confirmed that the maximum displacements at the center of flexure hinge diaphragms are several hundred times, compared with flat diaphragms. The sensitivities of fabricated miniature microphones are about $12.87{\mu}V/Pa$ at 1 kHz under a low bias voltage of 1 V, and the frequency response is flat upto 13 kHz.

• Journal of Chest Surgery
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• v.22 no.6
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• pp.1070-1077
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• 1989

Traumatic injuries of the diaphragm are not an infrequent occurrence with rise in violence and increasing use of automobiles, more diaphragmatic injuries may be seen. Fifty cases from Severance hospital were reviewed of these there were 27 injuries secondary to blunt trauma and 23 penetrating injuries, and occurred commonly in male. In blunt trauma, right and left diaphragmatic injuries occurred equally. Chest X * ray were normal in 18 cases [36 %], a hemo-and/or pneumothorax was present in 22 cases [44 %], and only 12 cases[24 %] were diagnosed or suspected as diaphragmatic injuries preoperatively. Seventeen cases underwent thoracotomy alone, 19 cases required laparotomy only, and 14 had combined thoracotomy and laparotomy. There were 5 deaths [10 % mortality], and all deaths related to the severity of associated injuries. It was concluded that injuries of the diaphragm should be suspected in all patients with severe blunt torso trauma or penetrating injuries near the diaphragm.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.403-407
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• 1988

Primary tumors of the diaphragm are very rare, From a clinical point of view, they do not present a specific symptomatology and the radiologic aspect is not characteristic. Their etiology is often obscure. The authors experienced one case of primary neurofibroma of the diaphragm. The patient was 52 year old male, and detected preoperatively abnormal round mass shadow in the middome portion of the left diaphragm in routine chest X-ray. A left posterolateral thoracotomy through the 7th ICS was performed. The mass and surrounding tissues were completely removed, and diagnosed as a primary neurofibroma by the histopathologic findings. Postoperative course was uneventful.

• Electrical & Electronic Materials
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• v.10 no.10
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• pp.1022-1028
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• 1997

In this paper we present the construction details and output characteristics of a diaphragm-type pressure sensor with Cu-Ni(53:47) thin-film strain gauges. In order to improve the sensitivity and the temperature compensation two circumferential gauges are placed near the center of the diaphragm and two radial gauges are located near the edge. For all the gauges the relative change in resistance ΔR/R with pressure is of the order 10$^{-3}$ for the maximum pressure. The output is found to be linear over the entire pressure range(0-30kfg/cm$^2$)and the output sensitivity obtained is 1.6mV/V. The maximum nonlinearity observed in output characteristics is 0.35%FS for 5V excitation and the hysteresis is less than 0.1%FS.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.559-560
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• 2006

The paper presents solutions of conventional piezoresistive pressure sensors. Deflection of diaphragm by external stress causes some problems, because the electrode is deposited on the diaphragm formed piezoresistors. To solve these problems, piezoresistors is formed by two implantation steps. To fabricate diaphragm, the backside silicon etching step is done by immersing the wafer into TMAH solution. $30{\mu}m$ thick diaphragm is obtained. Sensitivity of the piezoresistive pressure sensor fabricated is 48.6 mV/V-psi.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.5
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• pp.263-266
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• 2006

An optical microphone was developed using a dual-core multi-mode fiber block and a membrane type micromirror. The fiber block serves as a compact optical head, and the micromirror as a reflective diaphragm. The micromirror is designed to be suspended through a silicon bar connected t a frame, allowing for displacement induced by acoustic waves. The optical head is implemented by integrating two multi-mode fibers in a single block, and used to transfer light signals between it and the diaphragm. For the assembled microphone, its static characteristics were observed to reveal the operating point defined as the optimum distance between the optical head and the diaphragm. And its dynamic response was tested to exhibit a frequency bandwidth of 3 kHz with the variation of $\sim5dB$.