• Title/Summary/Keyword: Change point

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Bayesian Multiple Change-point Estimation in Normal with EMC

  • Kim, Jae-Hee;Cheon, Soo-Young
    • Communications for Statistical Applications and Methods
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    • v.13 no.3
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    • pp.621-633
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    • 2006
  • In this paper, we estimate multiple change-points when the data follow the normal distributions in the Bayesian way. Evolutionary Monte Carlo (EMC) algorithm is applied into general Bayesian model with variable-dimension parameters and shows its usefulness and efficiency as a promising tool especially for computational issues. The method is applied to the humidity data of Seoul and the final model is determined based on BIC.

비례위험모형에서 비례성 가정에 대한 검정: 도산모형에의 응용

  • Nam Jae-U;Kim Dong-Seok;Lee Hoe-Gyeong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.10a
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    • pp.615-618
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    • 2004
  • The previous quantitative bankruptcy prediction models cannot include time dimension. To overcome this limit, various dynamic models using survival analysis are developed recently. This paper emphasizes that the proportionality assumption must be adapted with caution when the Cox's proportional hazard model is used to explain bankruptcy. It is shown that a non-proportional hazard model including a change point model is a proper alternative, when the proportionality assumption is violated by the change of macroeconomic environment, such as the financial crisis in 1997.

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A Study on the Current Change in Final Closing Section (최종체절구간에서 유속변화에 관한 연구)

  • 신문섭;유시흥;이용래;권철휘;최용규
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.181-184
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    • 1999
  • The purpose of this study is to find on the Current Change and Residual current in Final closing section of Seamangum the sea dike . The M2 current was calculated in two case of the two and three point Final closing section. The residual currents are calculated diagnositically from the observed water temperature and salinity data and wind data and tidal residual current.

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A Study on Disaster Risk Assessment in the Urban Open Spaces (도시 녹지 공간의 재해 위험도 평가 연구)

  • Yu, Joo-Eun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.5
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    • pp.13-27
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    • 2015
  • This study examined disaster risk from climate change in urban open spaces. This study conducted an assessment depending on type of damage and type of open space, subcategorizing it into flood damage and wind damage, flat park and mountainous park, and classified the assessment items by type into natural factor, artificial factor, and social factor for the purpose of analysis. Our major findings from this study are as follows: To look at the standardized score for the disaster risk from flood damages in the case of a flat park, Asian Park was higher at 55.800 point than Seoul Forest at 51.775 point, and in the case of mountainous parks, Dogok Park was at 58.428 point and Baebongsan Park was at 58.374 point. To look at the standardized score for disaster risk from wind damage, in the case of a flat park, Asian Park was higher at 64.763 point than Seoul Forest at 61.054 point, and in the case of mountainous parks, Baebongsan Park was higher at 58.533 point than Dogok Park at 55.459 point. This study raised a question about the necessity for and value of this disaster risk assessment in open space from damages caused by climate change, established an assessment model for disaster risk from damages in open spaces only to attempt risk assessment. Disaster risk of urban green space was enhanced.

Soft tissue changes associated with ASO/BSSRO and Le Fort I/BSSRO in skeletal Class III malocclusion with upper lip protrusion (상순돌출을 동반한 골격성 III급 부정교합에서 수술방법에 따른 치료 후 상악 연조직 변화 - ASO/BSSRO와 Le Fort I/BSSRO 비교)

  • Kang, Ju-Man;Kim, Yoon-Ji;Park, Je-Uk;Kook, Yoon-Ah
    • The korean journal of orthodontics
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    • v.40 no.6
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    • pp.383-397
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    • 2010
  • Objective: The objective of this study was to compare maxillary soft tissue changes and their relative ratios to hard tissue changes after anterior segmental osteotomy (ASO)/bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I/BSSRO in skeletal Class III malocclusion with upper lip protrusion. Methods: The study sample comprised the ASO/BSSRO group (n = 14) and the Le Fort I/BSSRO group (n = 15). The Le Fort I/BSSRO group included cases of maxillary posterior impaction only. Lateral cephalograms were taken 2 months before and 6 months after surgery. Linear and angular measurements were performed. Results: The anterior maxilla moved backward in both groups after surgery, however the amount of change was significantly larger in the ASO/BSSRO group (p < 0.01). The ratios of hard to soft tissue change were 79% (SLS to A point), 80% (LS to A point) in the ASO/BSSRO group, and 15% (SLS to A point), 68% (LS to A point) in the Le fort I/BSSRO group. In addition, there was a $3.23^{\circ}$ increase of the occlusal plane in the Le Fort I/BSSRO group. Conclusions: When two-jaw surgery is indicated in skeletal Class III patients with protrusive lips, ASO may be a treatment of choice for cases with more severe upper lip protrusion, while Le Fort I with posterior impaction may be considered if an increase of occlusal plane angle is required.

STUDY ON MUTATION OF RAS GENE IN DMBA INDUCED CARCINOMA OF HAMSTER BUCCAL POUCH (DMBA로 유도된 햄스터 협낭암종에서 ras 유전자 변이에 관한 연구)

  • Song, Sun-Chul;Kim, Kyung-Wook;Lee, Jae-Hoon;Kim, Chang-Jin
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.6
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    • pp.581-590
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    • 2000
  • Alterations in the cellular genome affecting the expression or function of genes controlling cell growth and differentiation are considered to be the main cause of cancer. Over 30 oncogenes can be activated by insertional mutagenesis, single point mutations, chromosomal translocations and gene amplification. The ras oncogenes have been detected in $15{\sim}20%$ of human tumors that include some of the most common forms of human neoplasia and are known to acquire their transforming properties by single point mutations in two domains of their coding sequences, most commonly in codons 12 and 61. The ras gene family consists of three functional genes, N-ras, K-ras and H-ras which encode highly similar proteins of 188 or 189 amino acid residues generically known as P21. ras proteins have been shown to bind GTP and GTP, and possess intrinsic GTPase activity. Experimental study was performed to observe the mutational change of the ras gene family and apply the results to the clinical activity. 36 Golden Syrian Hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek (control side) was treated with mineral oil as the same manner of the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were completely dissected by microdissection and DNA from both tissue were isolated by proteinase K/phenol/chloroform extraction. Segments of the K-ras and H-ras gene were amplified by PCR using the oligonucleotide primers corresponding to the homologous region (codon 12 and 61) of the hamster gene, and then confirmational change of ras genes was observed by SSCP and autosequencing analysis. The results were as follows : 1. Malignant lesion could be found in the experimental side from the experimental six weeks. 2. One hamster among six showed point mutation of the H-ras codon 12($G{\rightarrow}A$ transition) at the experimental 10 and 14 weeks. 3. One of six at 6 weeks, two of six at 8 weeks and one of six at 12 weeks revealed the confirmational change of the H-ras codon 61($A{\rightarrow}T$ transversion). 4. The incidence of point mutation of H-ras codon 12 and 61 were 5.5%(2 of 36) and 11%(4 of 36) respectively. 5. Point mutation of the K-ras could not be seen during the whole experimental period. Form the above results, these findings strongly support the concept that H-ras oncogenes may have the influence of the DMBA induced carcinoma of hamster buccal pouch.

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Clinical Study of Different Effect between Trigger Point Needling and Remote Acupuncture Point Needling on Shoulder Pain Patient (견비통(肩臂痛)에 대한 Trigger Point 자침(刺鍼)과 원위취혈(遠位取穴)의 치료효과(治療效果)에 대한 임상적(臨床的) 비교(比較) 연구(硏究))

  • Lee, Jin-Seok;Song, Kye-Hwa;Lee, Seong-No;Kim, Dae-Jung;Yu, Jung-Suk;Nam, Hyo-Ik;Kim, Hoi-Young;Son, Hyun-Soo
    • Journal of Acupuncture Research
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    • v.24 no.5
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    • pp.89-96
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    • 2007
  • Objectives : This report is to compare Remote Acupuncture Point Needling group with Trigger Point Needling group about Shoulder pain treatment. Methods : From November 11th 2006 to May 10th 2007, 30 cases of shoulder pain patients were divided into 2 groups ; one group(test I group) took remote acupuncture point needling, and the other group(test II group) took trigger point needling. For evaluating change of pain, Visual Analog Scale(VAS) and clinical evaluation grade and Range of Motion was checked before and after Treatment. Results : Both acupuncture therapy showed good effect on shoulder pain. And test II group showed better effect on decreasing pain than test I group. It was proved by the difference between VAS and ROM checked before treatment and what checked after treatment. But it was only significant statistically for adduction, inversion and eversion of shoulder joint motion. Conclusion : Trigger point needling can be recommended as a useful therapy to treat shoulder pain.

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The Influence Of The Cathode Surface State On The Spark Voltage In The Low Pressure Gare Gas (저기압희유 gas중에서 불꽃전압에 미치는 음극표면상태의 영향)

  • 백용현
    • 전기의세계
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    • v.23 no.4
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    • pp.46-52
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    • 1974
  • Generally, it has been regarded that there are two kinds of the effect of the electrodes, especially of the cathode in the gas discharge, (a) the effect caused by the difference of the cathode meterial and (b) the effect by the change of the cathode surface state even in the same meterials. Thus the two effects must be investigated independently to study the roles of the cathode in gas discharges. This paper measured sparking voltage in Rare gas (Ar, He) for the change of sparking voltage in repeating sparks and for the effect of (a) and (b) mentioned above, under the condition that the desorption of impurities from the cathod can be nigligible, and it is obtained that the correlative relations of the work function, sparking voltage and secondary coefficient are comparatively simple. In addition, the interesting character of the minimum point of the paschen's curves is found. The results were as follows; 1) The value of (pd)min with minimum pint of sparking voltage, (Vs)min, is 0.7-0.9 Torr. cm in Argon, but is 5.6-7.1 Torr. cm in Helium, and Paschen's curve in Helium shows slow curve than in Argon. 2) The minimum point of the Paschen's curve is satisfied actually Townsend's self sustaining criterion in Argon, but non-satisfaction in Helium, and the Townsend's secondary coefficient .gamma. action have compound property (.gamma.$_{i}$, .gamma.$_{p}$, .gamma.$_{m}$) in Helium. 3) The dependenting character of work function in Helium is less than in Argon. 4) The minimum point of sparking voltage increase under oxidized electrode than clear electrode in Au and Ag, but minimum point decrease in Ni and Cu.

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Vertical Variations Analysis of Air Temperature and CO2 Concentration in the Grassplots (잔디밭에서 기온과 이산화탄소 농도의 연직 변동 분석)

  • So, Yoon Hwan;Kang, Dong Hwan;Kim, Il Kyu;Kim, Byung Woo;Yoon, Hwan Jin;Kim, Si Hyeon;Son, Yong Seok;Shin, Jung Hyeon;Ahn, Jeong Woo
    • Journal of Environmental Science International
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    • v.26 no.2
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    • pp.147-157
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    • 2017
  • This study investigated the characteristics of variations in carbon dioxide concentration and air temperature with the vertical change of surface in a grassplot. Field observations were carried out at a grassplot in Gyeongnam Science High School, over four days in August and November, 2015. Continuous observation equipment (GMP343, VAISALA) was installed at the LP (0.1 m from the surface) and UP (1.1 m from the surface) points, and the carbon dioxide concentration and air temperature were measured simultaneously at 1-min intervals. To summarize the results of the observation, August had higher than average concentrations of carbon dioxide, while November showed average air temperatures. Moreover, the concentration of carbon dioxide was higher at the UP point, while the air temperature was higher at the LP point. The correlation coefficient of carbon dioxide concentration between the UP and LP points was 0.80 in August across all the four days, while it was higher in November at 0.58-0.95. The results of the regression analysis of carbon dioxide concentration with air temperature changes for both August and November showed a distinct change at the LP point (R2=0.36-0.76), as compared to the UP point (R2=0.1-0.57). Between the UP and LP points, the carbon dioxide concentration and air temperature regression analysis results indicated that an active exchange was taking place between the two points.

The Longitudinal Relationships between Depression and Smoking in Hardcore Smokers Using Autoregressive Cross-Lagged Modeling

  • Han, Jeong Won;Lee, Hanna
    • Journal of Korean Academy of Nursing
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    • v.49 no.1
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    • pp.69-79
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    • 2019
  • Purpose: This study aimed to identify the directionality of the causal relationship and interaction between depression and amount of smoking over time in hardcore smokers using longitudinal descriptive analysis. Methods: Secondary data from the Korean Welfare Panel Study were analyzed using autoregressive cross-lagged modeling. Participants included 342 hardcore smokers who participated in the 8th to 11th waves of the panel study. Results: Analyses revealed that change(s) in depression levels according to time had a significant positive relationship with the total amount of smoking per day (${\beta}=.29$, ${\beta}=.19$, ${\beta}=.17$, p<.001), while change(s) in total amount of smoking per day according to time had a significant positive relationship with depression (${\beta}=.43$, ${\beta}=.50$, ${\beta}=.38$, p<.001). Analysis of the cross-lagged effect between depression and total amount of smoking per day showed that depression at one time point had a significantly positive relationship with the total amount of smoking per day at the next time point (${\beta}=.14$, ${\beta}=.13$, ${\beta}=.13$, p=.021), and that the total amount of smoking per day at one time point had a significant positive relationship with depression at the next time point (${\beta}=.04$, ${\beta}=.04$, ${\beta}=.03$, p=.044). Conclusion: The findings in the present study confirmed a cross-interaction between depression and total amount of smoking per day in hardcore smokers. The present findings could be used to develop appropriate smoking-related interventions.