국제복합운송에 관한 연구 (상학적 과제를 중심으로)

김천식 한국국제상학회 1988 國際商學 Vol.1 No.-

이달의 쟁점 : 남북협력기금, 삭감이냐 확충이냐 ; "남북협력사업 위해 확충 필요하다"

김천식 평화문제연구소 2006 통일한국 Vol.265 No.-

데이터베이스 기술

김천식 대한전자공학회 2008 電子工學會論文誌-CI (Computer and Information) Vol.45 No.3

大陸(中國)經濟圈과 西南港灣의 機能과 役割

김천식 한국항만경제학회 1995 韓國港灣經濟學會誌 Vol.11 No.-

Korean harbors have not played their important roles in spite of their having suitable condition to link the ocean and the continent, which was due to the blockade of trade with the continent socialist countries.<br/> But in the last 80's, korea normalized its relations with russia and china which were transformed into market economy. accordingly, it was necessary for the korean harbors in the southwestern areas to reshape their roles and functions.<br/> So this paper aims at presenting the equal development plan among areas between the continent and korea by studying their linking transportation of continental and reciprocal functions and distribution of roles.<br/> In the course of economic modernization, korea has changed its importance from the continent to the ocean.<br/> As a result, its emphasis was placed in establishing and developing harbors in the Pacific rims in order to act as a terminal between the land the ocean transportion.<br/> But recently, as korea has placed its emphasis on the continent again, it must take more open land development plan and the ocean-oriented play to keep pace with the internationalization.<br/> In recent years, Korea government has turned its key policy for the land management from the former restrainting policy of the capital spheres and equal development to establishing the strongpoints with a view to building up the national competitive power in the limitless competition period.<br/> So it designated the comparatively underdevloped southwestern areas as new industrial points and formed L-STYLE axis connecting KunSan, TaeBul and KwanGyang and made a special development plan for each area.<br/> In the coming twenties, the development of the south western harbors should be planned in the direction of enlarging their functions and adjusting the enlarged functions.<br/> InChon, situated the most closely to the mainland China, is a gateway to the Korean capital area and the most important harbor in west seashore.<br/> It is also expected to act as a key harbor in the period of the western seashore.<br/> The expansion of harbor facilities is a long-term project.<br/> To make good use of the harbor facilities, the functions of the harbors in the dock should be reallocated and the facilities of the outer port should be properly managed to accommodate the increased demand.<br/> Asan, situated in the southwestern site capital area ,has everything in common with InChon and rises to the surface as a promising quasi-capital harbor with the prospect of enlarging the trade with China, the establishment of express way in the southwestern districts, a larage consumption market and the effect of spill over.<br/> The development of Asan harbor should be made as an auxiliary port InChon an industrial port - and it should share the clearance of material resources and import goods for the rear industrial compex with InChon.<br/> It should also be a gateway to Seoul area in an emergency and developed to play its roles as an international trade port in the twenty first century.<br/> KunSan is facing with China across the ocean and expected to act as an advanced base for the policy toward the socialist countries.<br/> So the development of KunSan should be focused not only for the base in the southwestern and middle spheres of Korea but also for the stronghold of trade with China.<br/> In the marine transportation, the important harbors in every district should be specially developed and built up and specialized according to there functions, which will enhance the effectiveness of the harbor management and will conform with the direction of the long-term development plan.<br/> MokPo, situated on the comer of southwestern Korean peninsular, is a gateway to HoNam area.<br/> It is not only a strongpoint of international trade but also a forefront of the HoNam coastal fishery.<br/> So MokPo should be cultivated for the marine goods from the socialist countries to prepare for the increase of t

체위성 폐쇄성 수면 무호흡증의 유병률과 특성

김천식,이용석,조천웅,배상호,이상암 대한임상검사과학회 2012 대한임상검사과학회지(KJCLS) Vol.44 No.2

Patients with obstructive sleep apnea (OSA) often have more aggravated symptoms in the supine position. We tried to investigate the clinical characteristics and the predictive factors for positional OSA. Polysomnographic data were reviewed for OSA patients (apnea hypopnea index, AHI≥5) from April, 2008 to April, 2011 at the Asan Medical Center. Clinical data, comorbid medical condition data and questionnaires (SF-36, MFI-20, ESS, BDI, STAI) were assessed. All patients were classified into two groups: positional patients (PP) group and non-positional patients (NPP) group. PP was defined as a patient who had the AHI in the supine position was at least twice as high as that in the lateral position. The body position of patients was confirmed by sleep position sensor and video monitor. All patients had at least 30 minutes of positional and 30 minutes of non-positional sleep. We compared clinical, medical, polysomnographic data, and questionnaire results between two (PP and NPP) groups and investigated predictive factors for the PP group using binary logistic regression analysis. In total, 371 patients were investigated. 265 (71.4%) was categorized as PP group and 106 (28.5%) as NPP group. The mean age (mean±SD) was higher in the PP group (52.4±9.8) than in the NPP group (49.5±11.9) (p<0.05). Comparison of sleep parameters between the PP and the NPP group showed that the PP group had significantly lower BMI (PP: 26.1±3.2 kg/m2; NPP: 27.8±4.3kg/m2, p<0.001), neck circumference (PP: 39.7±2.8 cm; NPP: 41.5±3.7 cm, p<0.001) and hypertension rate (PP: n=89/265 (33.5%); NPP: n=48/106 (45.2%), p=0.0240). In the PP group, the percentage of deep sleep (PP: 8.7±8.1%; NPP: 5.6±7.0%, P=0.001) and rapid eye movement (REM) (PP: 17.5±6.1%; NPP: 14.0±6.9%, p<0.001) were significantly higher whereas the percentage of light sleep (stage N1) was significantly lower than the NPP group (PP: 30.4±12.3; NPP: 44.5±20.8%, p<0.001). During the sleep, the AHI in the supine position (PP: 48.6±19.5; NPP: 60.5±22.6, p<0.001) and in the non-supine position (PP: 9.4±8.9; NPP: 48.4±24.8, p=<0.001) were significantly lower and the minimal arterial oxygen saturation in non-REM sleep was significantly higher in the PP group (PP: 80.3±7.6; NPP: 75.1±9.9, p=<0.001). There were no significant differences in all questionnaires including quality of life. The results of the binary logistic regression analysis showed that age, the amount of REM sleep(%) and AHI were significant predictive factors for positional OSA. The significant predictive factors for positional OSA were older age, higher percentage of REM and lower AHI. The questionnaire results were not significantly different between the two groups. .

목젖 입천장 인두 절제술 전 후의 수면다원검사의 결과

김천식,김대식,이용석,조천웅,배상호,김원태 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.2

Uvulopalatopharyngoplasty (UPPP) is one possibility for the treatment of Obstructive Sleep Apnea (OSA). The aim of this study was study the analysis of polysomnography of pre-UPPP and post-UPPP. All patients were evaluated by means of a physical examination, the epworth sleepiness scale (ESS), the beck depression inventory (BDI) and the nocturnal polysomnography (PSG) before surgery, and 6∼12 months after surgery. A total of 15 patients were investigated. All underwent UPPP. The patients were between 26 and 62 years old (mean±SD; 39.7±10.9) with a lean body mass index (BMI) of mean±SD; 26.2±3.0 kg/m2. The comparison of sleep questionnaires showed that after UPPP, the patients had a significantly lower BMI (26.2±3.0 kg/m2 vs 26.0±3.4 kg/m2, p =0.241), ESS (10.0±5.4 vs 6.9±3.2, p =0.022), BDI (9.2±8.2 vs 4.2±4.3, p =0.343) and higher blood pressure (127.5±12.1 vs 123.7±12.0, p =0.272) compared to before UPPP. The comparison of sleep parameters showed that after UPPP, patients had a significantly lower stage N1 (108.8±53.1 vs 82.2±48.9, p =0.016), lower sleep latency (4.9±4.4 vs 2.0±1.7, p =0.083), a lower total arousal number (210.6±90.3 vs 147.1±87.3, p =0.019), lower oxygen desaturation index (ODI) (30.2±20.9 vs 10.2±15.1, p =0.006), lower apnea-hypopnea index (AHI) (31.6±22.4 vs 10.9±15.4, p =0.005), and a lower respiratory disturbance index (RDI) (37.4±21.3 vs 18.5±16.5, p =0.008) compared to after UPPP. The comparison of sleep parameters showed that after UPPP, patients had a significantly higher stage N2 (154.0±39.9 vs 180.5±49.5, p =0.017), higher REM (58.5±29.7 vs 72.6±34.0, p =0.249), higher meanSaO2 (94.3±2.0 vs 95.9±0.9, p =0.043), and higher minSaO2 (79.3±8.5 vs 83.1±7.9, p =0.116) than before UPPP. After UPPP, 6 patients were cured, 2 showed marked improvement, and 7 did not improve. After surgery, the success of the treatment was at 53%. The subjective patient satisfaction was higher than before the surgery.

세계 주요 港灣의 컨테이너 物動量 推移와 經營戰略 및 展望

金千植 木浦大學校 企業經營硏究所 1999 企業經營硏究 Vol.3 No.1

개정된 미국수면의학회 판독 기준이 무호흡 및 저호흡 지수에 미치는 영향

김천식,김민주,이은미,이용석,정유삼,이상암,김우성 대한수면연구학회 2010 Journal of sleep medicine Vol.7 No.2

Objectives: The definition of accurate recording and measuring of sleep related obstructive breathing events are clinically critical as a base for quantifying disease severity in obstructive sleep apnea (OSA) syndrome. The aim of the study was to compare apnea and hypopnea indices using different scoring recommendations. Methods: We retrospectively selected total 60 patients who were diagnosed with OSA syndrome. All sleep-related parameters including apnea index, hypopnea index, and apnea-hypopnea index (AHI) were measured by two different criteria; 1999 Chicago criteria and 2007 American Academy of Sleep Medicine (AASM) criteria for scoring respiratory events. Results: Apnea index and AHI by Chicago criteria were significantly higher than those by AASM criteria (mean 21.0/hr vs. 15.1/hr, p<0.001; mean 36.8/hr vs. 29.4/hr, p<0.001, respectively). But hypopnea index was not different between two criteria. Bland-Altman plots demonstrated a median (5th, 95th percentiles) reduction of 6.1/h (0.16, 20.57) when comparing AHI by AASM criteria to AHI by Chicago criteria. Conclusions: Our results suggested that AASM criteria intended to diagnose more confirmative OSA patients than Chicago criteria. Updated criteria may be stricter but possibly rule out mild OSA patients.

혈압과 폐쇄성수면무호흡-저호흡증후군의 연관성

김천식 대한임상검사과학회 2014 대한임상검사과학회지(KJCLS) Vol.46 No.3

Obstructive sleep apnea-hypopnea (OSAH) is known to be related to nocturnal blood pressure (BP) and hypertension. The aim of this study was to evaluate the prevalence of hypertension according to the apnea-hypopnea grading. A total of 2,210 adults with snoring and obstructive sleep apnea were referred to our sleep center from July 2009 to May 2013. Clinical blood pressure (BP) was measured before sleeping (bedtime BP) and immediately after waking up in the next morning (morning BP). Subjects were classified into four groups based on the apnea-hypopnea index (AHI) from PSG as follows: control group (n=470) simple snoring and with AHI<5; mild group (n=577) with AHI≥5 and <15; moderate group (n=508) AHI≥15 and <30; and severe group (n=655) with AHI≥30. The differences and correlations between BP and PSG parameters according to the AHI groups were analyzed. Patient's were classified as nomentensive (blood pressure <120/90 mmHg, n=700 ), prehypertensive (blood pressure <140-120≤mmHg, n=1297) hypertensive (blood pressure ≥140/90 mmHg, n=214) according to the office blood pressure measurements. The comparison of sleep parameters showed that OSA groups had a significantly higher stage N1 (control group vs. moderate OSA, severe OSA; 66.4±30.7 vs. 85.5±36.6, 128.4±57.3, p<0.001) and total arousal number (control vs. moderate OSA, severe OSA; 110.7±47.7 vs. 150.8±56.6, 236.6±95.8, p<0.001) compared to control group. The comparison of sleep parameters showed that OSA groups had a significantly lower stage N2 (control group vs. moderate OSA, severe OSA; 172.6±47.2 vs. 150.7±50.5, 120.3±57.4, p<0.001), stage N3 (control group vs. moderate OSA, severe OSA; 38.4±33.4 vs. 27.4±26.0, 56.1±27.5, p<0.001), REM (control group vs. moderate OSA, severe OSA; 64.3±25.5 vs. 56.1±27.5, 47.3±25.9, p<0.001) and mean SaO2% (control group vs. moderate OSA, severe OSA; 90.0±3.5 vs. 82.5±5.5, 70.0±8.8, p<0.001) compared to control group. The Apnea-hypopnea index was significantly higher in OSA groups, increased systolic and diastolic blood pressure than in the nomentensive group (bed time systolic pressure vs. AHI; <120 vs. 120-139, 140-159, >159; 17.5±18.6 vs. 24.9±21.0, 31.0±25.7, 42.3±31.7, p<0.001), (bed time diastolic pressure vs. AHI; 60-79 vs. 80-89, 90-99, >99; 19.3±19.7 vs. 22.4±20.3, 29.8±23.3, 38.8±28.5, p<0.001). AHI was positively correlated with morning systolic pressure, diastolic pressure, bed time systolic pressure and diastolic pressure (r=0.314, 0.279, 0.233 and 0.200, respectively, p<0.001). We conclude that BMI, Age, neck circumference and AHI increase with the blood pressure.

Data Hiding Based on BTC using EMD

김천식 한국인터넷방송통신학회 2014 한국인터넷방송통신학회 논문지 Vol.14 No.2

BTC는 단색 이미지 데이터의 압축을 위해서 사용되는 최근의 기술이다. BTC의 알고리즘은 평균과 표준편차 를 사용하여 구현한다. 데이터 은닉을 위해, 이미지의 비트-구조를 변경하는 과정이 요구된다. 이러한 변경은 BTC 이 미지의 질의 성능을 나쁘게 만든다. 따라서, 우리는 데이터 은닉의 성능 개선을 위해서 BTC를 개선한 IODBTC를 제 한하였다. 실험 결과 복원한 비밀 메시지가 원본 비밀 메시지와 같음을 증명하였고 제안한 방법이 이전의 스킴에 비해 서 좋은 BTC 이미지임을 증명하였다. Block truncation coding (BTC) is a recent technique used for compression of monochrome image data. The original algorithm of BTC implement to use the standard mean and the standard deviation. For data hiding, it is needed to modify bit-planes of an images. These modifications yields unacceptable quality of BTC images. Thus, we propose IODBTC (Improved Ordered dithering BTC) improving BTC. In this paper, we improve this problem. Experimental results show that the reconstructed secret messages are the same as the original secret messages, and that the proposed scheme exhibits a good BTC images compared to that of previous schemes.