• Transactions of the Society of Information Storage Systems
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• v.1 no.2
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• pp.188-191
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• 2005

Two different coverlayers which is useful for an optical buffer and a mechanical protection made of not only UV resin but also polycarbonate coversheet were prepared on small form factor optical disks. Thin coverlayer of 10 ${\mu}m$ and thick coverlayer of 80 ${\mu}m$ were fabricated. 10 ${\mu}m$-thick coverlayer was coated using UV resin material by spin coating method for the flying optical head application. On the other hand, 80 ${\mu}m$-thick coverlayer using coversheet with the resin bonding material was prepared for the non-flying optical head application. Both cases, the thickness uniformity seem to be the primary prerequisite factor, and it was analyzed. Thickness of 10 ${\mu}m$-thick UV resin coverlayer could be controlled within ${\pm}0.2m$ range and 80 ${\mu}m$-thick coversheet could be controlled within ${\pm}3{\mu}m$ range. However, the yield of such thickness tolerance was not good. New design of metal housing holder and polycarbonate outer ring was adopted to diminish the ski-jump phenomenon. Specifically, the polycarbonate outer ring was very effective to reduce the ski-jump. However, it should be careful to maintain uniform edge between disk and ring for the perfect coverlayer.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.194-199
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• 1999

Introduction: Since 1996, Dr. James Norman has successfully performed mimimally invasive radio-guided parathyroidectomy(MIRP) using intraoperative nuclear mapping with $^{99m}Tc$ sestamibi scanning and radioactivity detection probe. Objectives: We aimed to introduce this new surgical technique and evaluate it's efficacy by our own experiences. Method: From May to October 1999, five consecutive patients with primary hyperparathyroidism underwent parathyroidectomy by using modified MIRP technique. $^{99m}Tc$ sestamibi scanning was performed 1.0 or 1.5 hour before operation. After intraoperative localization of the tumor under the guidance of quantitative gamma counting with a NEVIGATOR probe, an unilateral small skin incision(3.0-4.0cm) was placed. Without a skin flap, the strap muscle was directly divided with the use of a Harmonic scalpel. After careful dissection, the parathyroid tumor was removed. Result: In all patients, a single adenoma could be easily detected and removed by this new technique. Mean incision length was 3.2cm(3.0-4.0cm) and operative time ranged from 40 to 110minute. All the patients were discharged within 2 days of surgery without any complication. Conclusion: This new operative technique could become the most minimally invasive alternative to the standard operative procedure for parathyroid adenoma.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.235-238
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• 1999

Parathyroid carcinoma is rare, occurring in less than 2-3% of the patients with primary hyperparathyroidism. In the patients with chronic renal failure, the incidence is extremely low. Only 13 cases of parathyroid carcinoma with chronic renal failure have been described in the world literature. We report a case of parathyroid carcinoma in a 43-year-old man who has been suffered from chronic renal failure for 19 years. To our knowledge, this is the first case of parathyroid carcinoma occurring in the thyroid gland associated with secondary hyperparathyroidism.

• Korean Journal of Head & Neck Oncology
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• v.4 no.1
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• pp.53-58
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• 1988

We have experienced 3 cases of papillary carcinoma of the thyroid gland seen as lateral neck cyst, Usually cystic lesions of the neck have been considered as benign lesions from clinical viewpoint. The usual differential diagnosis includes branchial cleft cyst, cystic hygroma, dermoid cyst, cold abscess(tuberculous lymphadenitis) and cavitating squamous cell carcinoma. A lateral neck cyst as the sole presenting complaint of the papillary thyroid carcinoma is very rare. Preoperative diagnosis of lateral neck cyst is often diagnostic dilemma. Fine-needle aspiration cytology can be helpful in detecting the cancer cells and in demonstrating the nature of the fluid component of the lateral neck cyst. Presence of brown murky fluid from the aspirated fluid is highly suggestive of thyroid carcinoma. The thyroid scans and B-mode ultrasonography mayor may not be helpful to detect the primary focus of the thyroid gland. We suggest that a patient with a lateral neck cyst in adult age group should be considered to be a possibility of underlying thyroid carcinoma presanting as lateral neck cyst.

• Transactions of the Society of Information Storage Systems
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• v.5 no.2
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• pp.76-81
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• 2009

Mobile devices have become an important part of daily life. This is especially true of laptop PCs, which are portable enough to be used almost anywhere. Laptop PCs, however, cannot be nomadic if each component is not robust enough to endure rugged laptop operating environment. Generally, external shock makes collision on head-disk interface and damage to read-write performance. To minimize the likelihood of failure, shock analysis must be incorporated into the design of hard disk drive in laptop. This research explores the structure modification of laptop HDD base, for improving shock performance using finite element analysis which considers the flexibility of whole HDD structure. FE model is verified by modal test and finely tuned. Then we obtained the transmitted acceleration of spindle and pivot and the relative displacement between disk and slider head as shock response. Based on shock simulation, the structural dynamics modification is performed and the primary design parameters are extracted.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.3
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• pp.187-192
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• 2009

Out of all oral malignant tumor, malignant lymphoma occurs in only 3.5%. Especially, most of the primary malignant lymphomas, which occur in the head & neck region are high-grade diffuse large B-cell lymphoma and mucosa-associated lymphoid tissue (MALT) marginal zone B-cell lymphoma is very rare. In the head & neck region, malignant lymphoma is reported to occur in the thyroid, salivary gland, trachea, larynx, orbital lobe and the Waldeyer's ring. Among the Waldeyer's ring, palatal tonsil is reported to be the most common region, but, only 1 case report was published in Korea. Until now, there were no case reports of MALT lymphoma that occurred in the tongue. The purpose of this case report is to report and discuss on a case of MALT lymphoma of the tongue.

• Current Optics and Photonics
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• v.4 no.3
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• pp.221-228
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• 2020

We developed an all-fiber RGB laser light source module for application in an automobile head-up display. It is based on laser diodes and an optical fiber combiner that substantially enhances the flexibility of configuration and stability against harsh working conditions for automobiles. We coupled 13 laser diodes with optical fibers and merged them into a single output with a beam combiner device. Red (R), green (G), and blue (B) laser sources were employed to produce primary colors that were mixed into a white light output. An optical output power of approximately 1.5 W was achieved, and the color balance of the output lights was assessed based on the CIE 1931 color space. The optical output power was shown to be stable for over 160 h within an optical fluctuation of less than 0.27%.

• Korean Journal of Head & Neck Oncology
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• v.35 no.1
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• pp.21-23
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• 2019

Recent studies have reported on the reconstruction of oral mucosal defects using acellular dermal matrix (ADM). This case report describes the reconstruction of a soft-palate mucosal defect using ADM. A 43-year-old man developed a $2.5cm{\times}3cm$ soft-palate mucosal defect after the removal of a lump on the soft palate andreconstructed the defect using ADM without further complications. Reconstruction of the soft palate with ADM could be more convenient than traditional methods including primary closure, skin graft, and local or free flap without complications.

• Korean Journal of Veterinary Research
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• v.61 no.3
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• pp.25.1-25.7
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• 2021

The axolotl has extraordinary regeneration capacity compared to other vertebrates. This remarkable potential has been attributed to its life-long neoteny, characterized by the exhibition of embryonic characteristics at the adult stage. A recent study provided a detailed morphological analysis of the sperm morphology of the Ambystoma mexicanum using routine and detailed histological techniques. The primary purpose of the present study is to describe a simple and inexpensive method for evaluating the morphology of axolotl sperm. In this study, spermatophore structures were collected and spread on slides and air-dried. The slides were stained with periodic acid Schiff, toluidine blue, Masson's trichrome, Giemsa, Spermac, and Diff-Quik dye for a morphological examination. The slides were coated with gold/palladium for a scanning electron microscopy examination. The sperm of the axolotl consisted of an elongated head, a neck, and a flagellum covered with an undulating membrane. The lengths of the midpiece, tail, and head were 8.575 ㎛, 356.544 ㎛, and 103.661 ㎛, respectively. In the flagellum part, the wavy membrane structure, whose function has not been explained, surrounds the tail. The data obtained from this study will constitute an important step in designing future research on the reproductive and regeneration capacity of the axolotl.

• Journal of Clinical Otolaryngology Head and Neck Surgery
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• v.29 no.2
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• pp.254-258
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• 2018

The solitary fibrous tumor (SFT) is a mesenchymal neoplasm that is described as spindle-shaped tumor cells on a collagenous background originating from pleural tissues. Recently, extrapleural SFT has been reported in nearly all sites, including the sublingual gland, parotid gland, nasal cavity and paranasal sinuses. Complete surgical excision is primary treatment for SFT, but diagnosing SFT is not often made until immunohistochemical evaluation after surgical resection. We report that the patient, 45-year-old male, was considered as a case of inflammation polyp arising from left nasal cavity with initial biopsy, however, it has turned out to be SFT after surgical treatment.