• 한국자동차공학회논문집
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• 제5권1호
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• pp.186-194
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• 1997

The objective of this study is to develope knock control algorithms which can increase engine power without causing frequent knock occurrence. A four cylinder spark-ignition engine is used for the experiments to develop knock control algorithms which use block vibration signals. Knock occurrence is detected accurately by using knock threshold values which consider the difference of transmission path of each cylinder. Spark timing is controlled both simultaneously and individually. With the simultaneous control, torque gain is achieved by retarding the spark timing on knock occurrence in propotion to the knock intensity. The individual knock control algorithm results in higher torque gain than the simultaneous knock control algorithm. The knock occurrence frequency of the individual knock control algorithm is about twice the value of the simultaneous knock control algorithm results. Both control algorithms give similar torque gain of about 3% when they are optimized.

• 대한기관식도과학회지
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• 제12권2호
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• pp.31-34
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• 2006

Simultaneous occurrence of medullary and papillary thyroid carcinomas in the same gland is very rare. In fact. there are only 18 cases of simultaneous occurrence of medullary and papillary thyroid carcinomas in the literature. We report a case of simultaneous medullary and papillary carcinoma of thyroid gland. A 67-year-old woman was diagnosed with medullary carcinoma of right lobe of thyroid gland and papillary carcinoma of left lobe of thyroid gland by fine needle aspiration cytology. Total thyroidectomy, anterior neck dissection, bilateral modified radical neck dissection and tracheotomy was undertaken. The tumor metastasized to regional lymph node and extrathyroidal muscle invasion of left papillary carcinoma was also revealed by pathological report. This report describes a case of thyroid carcinoma that demonstrated both medullary carcinoma and papillary components in the thyroid with lymph node metastasis.

• 아동학회지
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• 제29권6호
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• pp.147-161
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• 2008

The present study compared characteristics of Korean nominal particles (occurrence, error, error patterns) of ten 5- to 6-year-old Korean-English simultaneous bilingual children with ten Korean monolingual children. Data were analyzed by Mann-Whitney U test and Spearman Rank Correlation and by qualitative analysis. Results were (1) bilingual children showed significantly lower frequency based on the number of occurrence of nominal particles per utterance. (2) The error percentage of adverbial markers was significantly higher for bilingual children. (3) Error patterns of bilingual children showed a higher percentage of in-case substitution and double use error. These findings suggest that Korean-English simultaneous bilingual children have a different Korean nominal particles development from Korean monolingual children.

• Journal of Korean Neurosurgical Society
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• 제58권4호
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• pp.397-400
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• 2015

The simultaneous occurrence of an intracranial and a spinal subdural hematoma (SDH) is rare. We describe a case of cranial SDH with a simultaneous spinal SDH. An 82-year-old woman visited the emergency room because of drowsiness and not being able to walk 6 weeks after falling down. A neurological examination showed a drowsy mentality. Brain computed tomography showed bilateral chronic SDH with an acute component. The patient underwent an emergency burr-hole trephination and hematoma removal. She exhibited good recovery after the operation. On the fourth postoperative day, she complained of low-back pain radiating to both lower limbs, and subjective weakness of the lower limbs. Spine magnetic resonance imaging revealed a thoracolumbosacral SDH. A follow-up spinal magnetic resonance imaging study that was performed 16 days later showed a significant decrease in the size of the spinal SDH. We discuss the pathogenesis of this simultaneous occurrence of spinal and cranial SDH.

• 아태비즈니스연구
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• 제15권1호
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• pp.273-287
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• 2024

Purpose - This study conducts the co-occurrence analysis, one of the social network analysis using global OTA's online reviews and grades in order to understand the experience structure of foreign tourists visiting cutural tourism resources in Jeju, Korea. Design/methodology/approach - For this purpose, this study selects 6 cultural tourism resources in Jeju as the study sites, and collects qualitative review data (noun, adjectives, and verb) and quantitative grade data. Findings - The co-occurrence network analysis between words and grade of market and street shows that the grade of 5 appears the most simultaneous with pork, buy, lot, try, fresh, black, food, price, seafood, local, market, good, street, etc. and the grade of 1 connects with small, dish, better, taste, etc. And the co-occurrence network analysis between words and grade of tradition and folklore shows that the grade of 5 appears the most simultaneous with village, place, museum, visit, time, life, culture, women, diver, use, lot, etc. and the grade of 1 connects with minute, spend, room, recommend, honey, etc. Research implications or originality - The above research results are relevant in order to find out the core experience of foreign tourists using online review and grade generated by foreign tourists and use as the important information to develop the strategies related to the planning and management of cultural tourism resources.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권1호
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• pp.60-65
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• 2013

The maxillary floor sinus augmentation is considered as a safe and predictable procedure to ensure optimal implant placement. However, this procedure may have a variety of intra-surgical or post-surgical complications, also the major drawback of the procedure is deemed maxillary sinusitis. This case is a very unusual delayed occurrence of acute maxillary sinusitis after simultaneous maxillary sinus augmentation, using xenograft and implant placement. This report describes a serious complication of the maxillary sinus augmentation.

• Journal of Korean Neurosurgical Society
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• 제38권6호
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• pp.468-470
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• 2005

The recurrent intracerebral hemorrhage[ICH] in hypertensive patients is not an unusual event, but the simultaneous occurrence of multiple ICH is rare. A 70-year-old woman presented with bilateral simultaneous hypertensive intracerebral hemorrhages in both thalami. The complaints of the patient were unconsciousness [semicomatose mental state] and quadriparesis Grade II. The patient was managed conservatively. At discharge, the patient was awake [drowsy mental state], but Grade III according to the Glasgow Outcome Score. This paper reviews the clinical relevance, possible etiology, and treatment of bilateral thalamic ICH.

• 유통과학연구
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• 제21권5호
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• pp.101-111
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• 2023

Purpose: The purpose of this paper is to examine the effect of the VKOSPI index on short-term stock returns after a large-scale stock price shock of individual stocks of firms in the distribution industry in Korea. Research design, data, and methodology: This study investigates the effect of the change of the VKOSPI index or investor mood on abnormal returns after the event date from January 2004 to July 2022. The significance of the abnormal return, which is obtained by subtracting the rate of return estimated by the market model from the rate of actual return on each trading day after the event date, is determined based on T-test and multifactor regression analysis. Results: In Korea's distribution industry, the simultaneous occurrence of a bad investor mood and a large stock price decline, leads to stock price reversals. Conversely, the simultaneous occurrence of a good investor mood and a large-scale stock price rise leads to stock price drifts. We found that the VKOSPI index has strong explanatory power for these reversals and drifts even after considering both company-specific and event-specific factors. Conclusions: In Korea's distribution industry-related stock market, investors show an asymmetrical behavioral characteristic of overreacting to negative moods and underreacting to positive moods.

• 대한두경부종양학회지
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• 제17권1호
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• pp.52-55
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• 2001

We present a case of a mixed papillary and follicular thyroid cancer in a 45-year-old female presented with palpable mass on anterior neck area for 1 week ago. Neck CT and ultrasonogram revealed small solid masses in the both lobes of the thyroid gland. Thyroid scintigraphy presents as a cold nodule in the right lobe of the thyroid gland and FNA cytology demonstrated papillary thyroid cancer. At the time of operation, small sized solid masses were detected in the both lobes, and no cervical lymph nodes enlargement along the mass. Biopsies of the both mass demonstrated papillary cancer on right lobe and follicular cancer on left lobe. Simultaneous papillary and follicular thyroid cancer is an extremely rare clinical entity. We experienced a case of simultaneous papillary and follicular thyroid cancer, so we report it with a review of some articles.

• 천문학회보
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• 제36권2호
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• pp.80.2-80.2
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• 2011

The sudden decrease of galactic cosmic ray (GCR) intensity observed by ground neutron monitor (NM) is called a Forbush decrease (FD) event. The intensity time profile of FD event looks like the geomagnetic storm visualized by geomagnetic storm index Dst. Oh et al. [2008] and Oh and Yi [2009] classified the FD events into two kinds by criteria of the overlapping simultaneity of main phase in universal time (UT). The FD event is defined simultaneous if the main phase parts observed by the stations distributed evenly around the Earth are overlapped in UT and non-simultaneous if ones are overlapped in each station's local time (LT). They suggested the occurrence mechanisms of two kind FD events related to the interplanetary magnetic structures such as the interplanetary shock (IP shock) and magnetic cloud. According to their model, the simultaneity of FD depends on the strength and propagation direction of interactive magnetic structures overtaking the Earth. Now the STEREO mission can visualize the emergence and propagation direction of the coronal mass ejection (CME) in 3-dimension in the heliosphere. Thus, it is possible to test the suggested mechanisms causing two different types of FD events. One simultaneous FD observed on February 17, 2011 may be caused by a CME heading directly toward the Earth observed on February 15, 2011 by the STEREO mission. The simultaneity of FD event is proved to be a useful analysis tool in figuring out the geo-effectiveness of solar events such as interplanetary CMEs and IP shocks.