• Journal of Yeungnam Medical Science
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• v.23 no.2
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• pp.227-231
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• 2006

The Valsalva maneuver is described as an expiratory effort against a closed glottis or airway. It leads to elevation of retinal venous pressure and may result in retinal hemorrhage. A fifty two- year-old man presented with an acute reduction of central visual acuity in his right eye which occurred after considerable straining at stool. Detailed past medical history revealed that he suffered from chronic constipation and hypertension. There were one disc sized subhyaloid hemorrhage and three small intraretinal hemorrhages around the fovea at the dilated fundus examination. After three months of follow-up without any treatment, the retinal hemorrhages resolved without any sequelae. Here we report a patient with sudden visual loss and retinal hemorrhage.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2471-2473
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• 2003

인간의 안구는 색과 모양을 식별하는 데에 관여하는 원추 세포와 물체의 명암을 구분하는 간상 세포로 구성되어지는 시세포를 가진다. 망막 위에 분포되어 있는 시세포들은 시축을 중심으로 각기 다른 밀도로 분포 되어 있다. 특히 광축과 만나는 중심 지역은 Fovea라고 하는 직경 1mm 정도의 작은 우물을 이루고 있는데 원추 세포들이 고해상도로 분포되어 있고 시신경과 일대일로 연결되어 있어 시각 처리의 중심이 된다. 특히, 글자나 물체를 인식하기 위해 인간은 대상물을 응시하여 대상물의 영상이 Fovca영역에 맺히도록 추적 운동을 계속한다. 본 논문에서는 인간의 눈과 유사한 망막 모델의 하나인 Log-polar Image를 이용한 물체 인식을 위해 물체를 Log-polar Image Plane의 중심에 위치시키기 위한 모멘텀(Momentum)기반 정합 알고리즘(Alignment Algorithm)을 제시한다. 이는 눈동자 운동이 가능한 능동형 시각 장치의 Tracking 및 Pursuit 동작 중에 밭생하는 추적 오차를 보상함으로써 운동 중에도 효과적인 물체 인식이 가능하게 한다. 또한, 물체를 Log-polar Image Plane의 중심에 위치시킴으로써 물체의 위치 이동, 회전이동 그리고 크기 변화에 무관하게 물체를 인식한 수 있음을 제시한다.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.507-514
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• 2021

A new free-living marine nematode species of the genus Pseudosteineria Wieser, 1956 affiliated with the family Xyalidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Pseudosteineria varisetis sp. nov differed from its congeners by the combination of the following characteristics: a relatively long body (1,628-1,691 ㎛ long in males), a circular amphideal fovea situated behind the subcephalic setae, the presence of lateral cuticular alae starting from behind the nerve ring, the presence of eight groups of long subcephalic setae, the presence of irregularly distributed variable lengths of somatic setae on the body, solid spicules (43.2-43.9 ㎛ long) with a cephalated proximal end, a long tubular shaped gubernaculum with dorsal swelling, and a conico-cylindrical tail with two to four terminal setae. In this report, we provide a taxonomic description and illustrations of a new species of the genus Pseudosteineria by differential interference contrast microscopy.

• Journal of Species Research
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• v.12 no.2
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• pp.122-149
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• 2023

Two known species of the family Comesomatidae Filipjev, 1918 were collected from marine sediments of the sublittoral zone in the East Sea, Korea and described and illustrated. Dorylaimopsis variabilis Muthumbi, Soetaert and Vincx, 1997, which was originally described from the Kenyan coast in the Indian Ocean, is recorded from the East Sea, Korea for the first time; there are only slight differences in amphidial fovea turns, body length, body width and relative length of tail. Setosabatieria hilarula (De Man, 1922), Platt, 1985, which was originally described from the North Sea, is recorded from the East Sea, Korea for the first time; there are only slight differences in the number of precloacal supplements, the relative length of tail and the posterior portion of tail. We provide pictorial keys for determination of valid species in the genera Dorylaimopsis Ditlevsen, 1918 and Setosabatieria Platt, 1985. This is the first description of the genus Dorylaimopsis and Setosabatieria from Korean waters.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.579-590
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• 2022

Three free-living marine nematodes(Desmoscolex(Desmoscolex) max Timm, 1970, Daptonema longiapophysis Huang and Zhang, 2010, and Pseudosteineria sinica Huang and Li, 2010) were newly recorded in Korea. Desmoscolex (D.) max was found from subtidal coarse sediment around Wangdolcho in the East Sea. It was characterized by the presence of untypical setae arrangement, obviously elongated triangle-shaped head, long hairy cephalic setae, a long naked tail spinneret, and the absence of peduncle at the base of somatic setae. Daptonema longiapophysis was obtained from intertidal sandy sediments in the southern coast of Korea. It was characterized by the presence of setiform labial sensilla, spicules with a projection on both sides, and gubernaculum with dorso-caudal apophysis. Pseudosteineria sinica was discovered from the intertidal sediment in the Yellow Sea. It was characterized by unobservable amphideal fovea, different lengths of spicules, and gubernaculum with dorso-caudal apophysis. In this study, we provide detailed morphological features of three free-living marine nematodes by differential interference contrast microscopy.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.5-9
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• 2003

The fused thoracic vertebra and deformity of the lumbar vertebrae in the female Thoroughbred horse were observed macroscopically. The 11th and 12th thoracic vertebrae (T) were partially fused. They were composed of three parts between the spinous process of the 11th and 12th T, left and right caudal articular processes of the 11th T, and left and right cranial articular processes of the 12th T. The vertical surface of cranial articular process of the 11th T and left mamillary process of the 12th T were absent. The left caudal part of the transverse process of the 12th T and left costal fovea of the transverse process of the 12th T were severely deformed. On the other hand, the left transverse process of the first lumbar vertebra (L) was a typical rib-like transverse process and two times longer than the right transverse process of the 2nd L. The right transverse process of 4th L has an oval concave facet on the medial part of caudal border for articulation with the right transverse process of 5th L; the latter has a corresponding convex facet on the medial part of the cranial border in the right transverse process of the 5th L.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.81-91
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• 2005

A new species of draconematid nematode, Paradraconema jejuense n. sp., is described from the shallow sublittoral coarse sediments of Jeju Island, Korea. Paradraconema jejuense n. sp. is most similar to P. antarcticum Allen and Noffsinger, 1978 in having similar habitus (long slender body) and amphideal fovea (doubled elongate spiral in male and circular spiral in female), but is distinguished by the following characteristics: larger number of posterior sublateral adhesion tubes (10 in male and 11-12 in female) and subventral adhesion tubes (16 in male and 17-18 in female), fewer cephalic acathiform setae on rostrum (a pair of small cephalic acathiform setae in both sexes), the absence of eye-spots, and the presence of a differentiated lateral field in mid-body region. This is the first taxonomic report on Paradraconema species from Korea.

• Journal of Convergence for Information Technology
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• v.11 no.1
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• pp.20-27
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• 2021

Eye tracking is one of the NUI technologies, and it finds out where the user is gazing. This technology allows users to input text or control GUI, and further analyzes the user's gaze so that it can be applied to commercial advertisements. In the eye tracking system, the allowable range varies depending on the quality of the image and the degree of freedom of movement of the user. Therefore, there is a need for a method of estimating the accuracy of eye tracking in advance. The accuracy of eye tracking is greatly affected by how the eye tracking algorithm is implemented in addition to hardware variables. Accordingly, in this paper, we propose a method to estimate how many degrees of gaze changes when the pupil center moves by one pixel by estimating the maximum possible movement distance of the pupil center in the image.

• Journal of The Korean Ophthalmological Society
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• v.58 no.8
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• pp.960-967
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• 2017

Purpose: To compare the macular choroidal thickness in patients with thyroid-associated ophthalmopathy (TAO) with those with normal tension glaucoma (NTG). Methods: A total of 70 normal eyes, 74 eyes with TAO and 60 eyes with NTG were enrolled in this study. All patients underwent spectral-domain optical coherence tomography (SD-OCT) (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA). Macular choroidal thickness was assessed using enhanced depth imaging. The average macular choroidal thickness was defined as the average value of three measurements: at the fovea and at the points located 1.5 mm in the nasal and temporal directions from the fovea. Generalized estimating equations were used to uncover factors affecting the average macular choroidal thickness. Results: The average, superior and inferior quadrant retinal nerve fiber layer thicknesses were significantly thinner in the NTG group compared with the TAO and control groups (p < 0.001). The average macular choroidal thickness of the TAO group, NTG group and controls was $281.01{\pm}60.06{\mu}m$, $241.66{\pm}55.00{\mu}m$ and $252.07{\pm}55.05{\mu}m$, respectively, which were significantly different (p = 0.013). The subfoveal, nasal and temporal side choroidal thicknesses were significantly thinner in the NTG group compared with the TAO group (p = 0.014, 0.012 and 0.034, respectively). Subjects with TAO were associated with a thicker average macular choroidal thickness compared with the NTG group after adjusting for age, sex, spherical equivalent and intraocular pressure (${\beta}=32.61$, p = 0.017). Conclusions: Macular choroidal thickness was significantly thicker in patients with TAO compared with those with NTG. Further evaluation is required to determine if a thick choroid in subjects with TAO has any role in glaucomatous optic neuropathy.

• Science of Emotion and Sensibility
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• v.18 no.4
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• pp.3-14
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• 2015

This study has extracted observation data by spatial factor for the analysis of subjects' selective attention with the objects of public space at the entrance of subway stations. The methods extracting observation data can be summarized as the following. First, the frequency analysis by lattice was prevalent for those methods, but there is a limitation to the analysis of the observation data. On the contrary, the method extracting observation data by factor applied in this study can make it clear if any sight is concentrated on any particular factors in a space. Second, the results from the extracted data corresponding to the observation area can be objectified while the method setting up the observation area by applying the radius of fovea. Third, time-sequential trace of observation results of relevant factors was possible through hourly analysis of spatial factors. The consideration of the results of "corresponding spatial scope" which is the object of this study will reveal that the more the observation time, the less the degree of attention it receives. Fourth, the frequency of observation superiority was applied for the analysis of the sections with selective attention by time scope; this revealed that men and women had intensive observation in time scope I (52.4 %) and in time scope IV (24.0 %), respectively.