• Biomedical Engineering Letters
• /
• 제8권4호
• /
• pp.355-364
• /
• 2018

When focusing using an ultrasonic transducer array, a main lobe is formed in the focal region of an ultrasound field, but side lobes also arise around the focal region due to the leakage. Since the side lobes cannot be completely eliminated in the focusing process, they are responsible for subsequent ultrasound image quality degradation. To improve ultrasound image quality, a signal processing strategy to reduce side lobes is definitely in demand. To this end, quantitative determination of main and side lobes is necessary. We propose a theoretically and actually error-free method of exactly discriminating and separately computing the main lobe and side lobe parts in ultrasound image by computer simulation. We refer to images constructed using the main and side lobe signals as the main and side lobe images, respectively. Since the main and side lobe images exactly represent their main and side lobe components, respectively, they can be used to evaluate ultrasound image quality. Defining the average brightness of the main and side lobe images, the conventional to side lobe image ratio, and the main to side lobe image ratio as image quality metrics, we can evaluate image characteristics in speckle images. The proposed method is also applied in assessing the performance of side lobe suppression filtering. We show that the proposed method may greatly aid in the evaluation of medical ultrasonic images using computer simulations, albeit lacking the use of actual experimental data.

• 한국광학회지
• /
• 제12권5호
• /
• pp.356-361
• /
• 2001

공초점 현미경에서 광축 방향의 상을 얻을 때 잡음으로 작용하는 side-lobe의 영향을 조사하였다. 이러한 side-lobe는 Herschel 조건을 만족시킴으로써 최소화시킬 수 있다. 본 연구에서는 side-lobe에 대한 영향을 전산 시늉하였고, 이 결과를 실험에 적용하여 Herschel 조건에 의해 위상 보정을 함으로써 side-lobe가 최소화됨을 확인하였다.

• Journal of Chest Surgery
• /
• 제56권2호
• /
• pp.140-142
• /
• 2023

The azygos vein sometimes merges abnormally across the right upper lobe of the lung and it hangs at the lower edge of a membranous septum, called the meso-azygos. The septum invaginates the lobe and makes a fissure. The smaller medial part of the right upper lobe is called an azygos lobe. A 16-year-old male patient was diagnosed with right-sided pneumothorax, and a closed thoracostomy was done in the emergency room. During elective wedge resection including the bulla, the meso-azygos, abnormal azygos vein, and azygos lobe were detected. We reviewed the computed tomography images and found that the azygos lobe had re-expanded laterally, not medially, to the meso-azygos after the closed thoracostomy in the emergency room. The patient had been diagnosed with left-sided pneumothorax a year ago, and no one noticed the azygos lobe at that time. We report the intraoperative findings and comparative images of a migratory azygos lobe.

• 대한수의학회지
• /
• 제7권1호
• /
• pp.8-18
• /
• 1967

Casting specimens of portal system and hepatic vein system in livers were made by injection of vinylite into the portal vein and postcava in 20 adult dogs. The author classificated the ramification of portal system and hepatic vein system. The results obtained were summerized as follows: 1. Portal system in livers were divided into left and right trunks. The left trunk subdivided into papillary process (caudate lobe,) left medial lobe, left lateral lobe, quadrate lobe and right medial lobe rami. The right trunk were subdivided into right lateral lobe and caudate proccss(caudate lobe.) 2. The lateral superior and medial inferior rami of portal system in left lateral lobe were subdivided 1 or 2 branches from left trunk. 3. The lateral superior ramus of portal system in left medial lobe did not appeared in 40% of the cases examined. 4. Portal system in quadrate lobe were subdivided 1-3 branches from left trunk, 5. Portol system in right medial lobe rami were relatively simple in ramification. 6. The lateral superior and medial inferior rami of portal system in right lateral lobe were subdivided 1 or 2 branches from right trunk. 7. Hepatic vein system of left lateral, left medial, quadrate and right medial lobe rami were originated from same ramus divided from the postcava in all cases. 8. Hepatic vein system of left and right rami in right medial lobe were divided from postcava.

• 한국인터넷방송통신학회논문지
• /
• 제22권4호
• /
• pp.59-65
• /
• 2022

본 논문에서는 디지털 능동위상배열 안테나를 간략히 소개하고 주 빔의 부엽을 차단하기 위해 적용된 이중 채널 부엽 차단 빔 형성 방법에 대해 기술하였다. 그리고 안테나 주 빔 및 부엽 차단 빔 설계 결과와 안테나 근접전계 측정 결과로부터 안테나 성능을 검증하였다. 다음으로 기존의 이중 채널 부엽 차단 빔 운용 방식 보다 채널수를 줄이기 위해 단일 채널 부엽 차단 빔 형성 방법을 제안하고, 제안한 방법으로 부엽 차단 안테나에 대한 소자별 가중치 분포를 설계하였다. 마지막으로 설계된 단일 채널 부엽 차단 빔 패턴과 차단 능력을 검증하고 이중 채널 부엽 차단 빔과 비교하였다. 또한, 디지털 능동위상배열 안테나의 수신 근접전계 시험을 통해 측정한 이중 채널 부엽 차단 빔과 제안된 단일 채널 부엽 차단 빔 패턴 및 부엽 차단 성능을 비교/검증함으로써 제안된 부엽 차단 빔 형성 방법에 대한 유효성을 확인하였다.

• 대한음성학회:학술대회논문집
• /
• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
• /
• pp.59-63
• /
• 2007

Neuromagnetic fields were recorded from normal 10 subjects to investigate the time course of cerebral neural activation during the resolution of lexical ambiguity. All recordings were made using a whole-head 306-channel MEG (Elekta Neuromag TM Inc., $Vectorview^{TM}$). The observed activity was described by sLORETA (standardized low resolution brain electromagnetic tomography) techniques implemented in CURRY software (Neuroscan). In the results, bilaterally occipito-temporal lobe was activated at 170ms. At 250ms was associated with bilateral temporal lobe during ambiguous condition, whereas in left parietal, temporal lobe on unambiguous condition. The left frontal lobe, temporal lobe were activated at 350ms for all condition. At approximately 430ms, was activated in right frontal, temporal lobe on the resolving ambiguous condition, in left parietal lobe, right temporal lobe on the preserving ambiguous condition. In conclusion, the cerebral activations related to the resolving lexical ambiguity were right frontal lobe and the areas of mountainous ambiguity were left parietal lobe.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제35권5호
• /
• pp.384-387
• /
• 2009

Tumors of the deep lobe of parotid gland are rare. These benign tumors have usually been treated by total parotidectomy, which has functional and esthetic side effects. Recently, there has been a trend for operations of parotid gland benign tumors to be less radical and selective deep lobe parotidectomy has been introduced. This technique preserves the superficial lobe and facial nerve when tumor is located in the deep lobe. Selective deep lobe parotidectomy preserves parotid salivary function, minimizes the incidence of facial nerve damage and gustatory sweating (Frey's syndrome) and improves cosmetic outcome. We report a case of pleomorphic adenoma of the deep lobe that was successfully treated by selective deep lobe parotidectomy with satisfactory result.

• 한국자동차공학회논문집
• /
• 제8권6호
• /
• pp.101-110
• /
• 2000

A Computer program is developed for creation of a new lobe shaper for Roots-type supercharger. Numerical analyses are preformed for the flowfields in the pocket volumes formed by various lobe shapes. The governing equations for the two-dimensional, turbulent, operational processes in the housing are discretized by the control volume approach that insures the conservative characteristics to be satisfied in the calculation domain, and they are solved by a modified SIMPLE algorithm. Numerical results show that the effects of secondary flow on the leakage flow rate with the Cassini(B) lobe shape is smaller than that of Cassini(A) rotor. But the pocket volume of Cassine(B) lobe is larger than the other lobe shapes.

• 한국동물학회지
• /
• 제33권1호
• /
• pp.28-34
• /
• 1990

배추흰나비에서 좌측 촉각을 제거한지 1일 또는 2일후 뇌의 좌측배엽을 전자현미경으로 관찰하여 촉각으 촉각지각신경세포가 배엽에 종지하는지를 조사하였다. 촉각지각신경세포는 촉각제거로 받은 큰 손상으로 말미암아 배엽에서는 그 축색종말에 전자밀도가 낮거나, 중등도이거나 또는 높은 퇴행성변화를 나타내었다. 그러므로 뇌로 뻗은 촉각지각신경세포중 일부는 촉각 바로 뒤에 있는 배엽에 종지한다고 결론되었다.

• 한국산학기술학회:학술대회논문집
• /
• 한국산학기술학회 2002년도 추계학술발표논문집
• /
• pp.201-204
• /
• 2002

Overlay margin 확보를 위한 oversizing과, design rule checking, jog filtering를 통하여 side-lobe를 추출하였다. 이렇게 추출한 side-lobe를 extent하고, Cr pattern을 정의하여 side-lobe 현상을 해결할 수 있었다. 하지만 이 방법은 mask제조 공정이 복잡하므로 Cr shield방식의 단점인 복잡한 mask제작공정과 구조를 단순화하기 위하여 scattering bar를 이용하였다. 따라서, scattering bar를 삽입하기 위한 rule을 생성하여 metal layer에 적용하고 aerial image simulation을 통해 side-lobe 현상이 억제되었음을 확인하였다. 그리고 앞에서와는 반대로 background clear의 경우에 발생하는 side-lobe에 scattering bar를 적용하여 억제됨을 확인하였다.