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A Patient with a Diagnosis of Spinal Neurofibroma and Complaining of Lower Back Pain: A Case Report, Including Two Follow-ups after Discharge (척추 신경섬유종 진단을 받은 요통 환자에 대한 복합적 한방처치 및 영상학적 경과 관찰 증례 보고 1례)

  • Moon, Heeyoung;Ryu, Gwang-hyun;Ju, Ah-ra;Choi, Yo-sup;Choo, Won-jung;Park, Ji-won;Kim, Doori;Jeon, Yong-hyun
    • The Journal of Internal Korean Medicine
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    • v.40 no.5
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    • pp.938-947
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    • 2019
  • Objective: This study was performed to report the changes in symptoms and radiological consequences of a patient diagnosed with spinal neurofibroma and complaining of lower back pain. Methods: The patient was diagnosed with a spinal neurofibroma after MRI examination and was treated with traditional Korean medicine, including traditional Korean medication and acupuncture. We measured the change in symptom severity using a numerical rating scale (NRS) and the Oswestry Disability Index (ODI). We also used the EQ-5D (EuroQoL-5D) scale to assess the patient's quality of life. In addition, we examined the change in the size of the cyst by MRI twice after discharge: at about 3 months after discharge and at about 8 months after discharge. Results: After about 6 weeks of treatment, most pathological symptoms had decreased. The patient showed a decline in NRS and ODI scores and showed an increase in quality of life. The two MRI examinations after the discharge revealed a decrease in the size of the cyst. Conclusions: Traditional Korean medicine can be a solution for patients with spinal neurofibroma causing neurological pain.

Evaluation of Predictability of Global/Regional Integrated Model System (GRIMs) for the Winter Precipitation Systems over Korea (한반도 겨울철 강수 유형에 따른 전지구 수치모델(GRIMs) 예측성능 검증)

  • Yeon, Sang-Hoon;Suh, Myoung-Suk;Lee, Juwon;Lee, Eun-Hee
    • Atmosphere
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    • v.32 no.4
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    • pp.353-365
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    • 2022
  • This paper evaluates precipitation forecast skill of Global/Regional Integrated Model system (GRIMs) over South Korea in a boreal winter from December 2013 to February 2014. Three types of precipitation are classified based on development mechanism: 1) convection type (C type), 2) low pressure type (L type), and 3) orographic type (O type), in which their frequencies are 44.4%, 25.0%, and 30.6%, respectively. It appears that the model significantly overestimates precipitation occurrence (0.1 mm d-1) for all types of winter precipitation. Objective measured skill scores of GRIMs are comparably high for L type and O type. Except for precipitation occurrence, the model shows high predictability for L type precipitation with the most unbiased prediction. It is noted that Equitable Threat Score (ETS) is inappropriate for measuring rare events due to its high dependency on the sample size, as in the case of Critical Success Index as well. The Symmetric Extreme Dependency Score (SEDS) demonstrates less sensitivity on the number of samples. Thus, SEDS is used for the evaluation of prediction skill to supplement the limit of ETS. The evaluation via SEDS shows that the prediction skill score for L type is the highest in the range of 5.0, 10.0 mm d-1 and the score for O type is the highest in the range of 1.0, 20.0 mm d-1. C type has the lowest scores in overall range. The difference in precipitation forecast skill by precipitation type can be explained by the spatial distribution and intensity of precipitation in each representative case.

Hygro-thermo-mechanical bending response of FG plates resting on elastic foundations

  • Merazka, Bouzid;Bouhadra, Abdelhakim;Menasria, Abderrahmane;Selim, Mahmoud M.;Bousahla, Abdelmoumen Anis;Bourada, Fouad;Tounsi, Abdeldjebbar;Benrahou, Kouider Halim;Tounsi, Abdelouahed;Al-Zahrani, Mesfer Mohammad
    • Steel and Composite Structures
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    • v.39 no.5
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    • pp.631-643
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    • 2021
  • The aim of this work is to study the hygro-thermo-mechanical bending responses of simply supported FG plate resting on a Winkler-Pasternak elastic foundation. The effect transverse shear strains is taken into account in which the zero transverse shear stress condition on the top and bottom surfaces of the plate is ensured without using any shear correction factors. The developed model contains only four unknowns variable which is reduced compared to other HSDTs models. The material properties of FG-plate are supposed to vary across the thickness of the plate according to power-law mixture. The differential governing equations are derived based on the virtual working principle. Numerical outcomes of bending analysis of FG plates under hygro-thermo-mechanical loads are performed and compared with those available in the literature. The effects of the temperature, moisture concentration, elastic foundation parameters, shear deformation, geometrical parameters, and power-law-index on the dimensionless deflections, axial and transverse shear stresses of the FG-plate are presented and discussed.

Investigation on the dynamic response of porous FGM beams resting on variable foundation using a new higher order shear deformation theory

  • Atmane, Redhwane Ait;Mahmoudi, Noureddine;Bennai, Riadh;Atmane, Hassen Ait;Tounsi, Abdelouahed
    • Steel and Composite Structures
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    • v.39 no.1
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    • pp.95-107
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    • 2021
  • In this work, the dynamic response of functionally graded beams on variable elastic foundations is studied using a novel higher-order shear deformation theory (HSDT). Unlike the conventional HSDT, the present one has a new displacement field which introduces undetermined integral variables. The FG beams were assumed to be supported on Winkler-Pasternak type foundations in which the Winkler modulus is supposed to be variable in the length of the beam. The variable rigidity of the elastic foundation is assumed to be linear, parabolic and sinusoidal along the length of the beam. The material properties of the FG porous beam vary according to a power law distribution in terms of the volume fraction of the constituents. The equations of motion are determined using the virtual working principle. For the analytical solution, Navier method is used to solve the governing equations for simply supported porous FG beams. Numerical results of the present theory for the free vibration of FG beams resting on elastic foundations are presented and compared to existing solutions in the literature. A parametric study will be detailed to investigate the effects of several parameters such as gradient index, thickness ratio, porosity factor and foundation parameters on the frequency response of porous FG beams.

Bending analysis of functionally graded plates using a new refined quasi-3D shear deformation theory and the concept of the neutral surface position

  • Hachemi, Houari;Bousahla, Abdelmoumen Anis;Kaci, Abdelhakim;Bourada, Fouad;Tounsi, Abdeldjebbar;Benrahou, Kouider Halim;Tounsi, Abdelouahed;Al-Zahrani, Mesfer Mohammad;Mahmoud, S.R.
    • Steel and Composite Structures
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    • v.39 no.1
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    • pp.51-64
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    • 2021
  • This paper presents a high-order shear and normal deformation theory for the bending of FGM plates. The number of unknowns and governing equations of the present theory is reduced, and hence makes it simple to use. Unlike any other theory, the number of unknown functions involved in displacement field is only four, as against five or more in the case of other shear and normal deformation theories. Based on the novel shear and normal deformation theory, the position of neutral surface is determined and the governing equilibrium equations based on neutral surface are derived. There is no stretching-bending coupling effect in the neutral surface-based formulation, and consequently, the governing equations of functionally graded plates based on neutral surface have the simple forms as those of isotropic plates. Navier-type analytical solution is obtained for functionally graded plate subjected to transverse load for simply supported boundary conditions. The accuracy of the present theory is verified by comparing the obtained results with other quasi-3D higher-order theories reported in the literature. Other numerical examples are also presented to show the influences of the volume fraction distribution, geometrical parameters and power law index on the bending responses of the FGM plates are studied.

Combined Korean Medicine Treatment of Lumbosacral Transitional Vertebra with Localized Bone Marrow Edema: A Case Report (이행성 척추에 동반된 골수부종 환자의 복합한방치료: 증례보고)

  • Chai, Jiwon;Lee, Yunha;Choi, Dongjoo;An, Sang-joon;Choi, Hyunjin;Hwangbo, Sengyoon;Baek, Hyekyung
    • Journal of Korean Medicine Rehabilitation
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    • v.32 no.1
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    • pp.125-131
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    • 2022
  • This study was to investigate the effectiveness of combined Korean medicine treatment on a patient who was diagnosed on lumbosacral transitional vertebra (LSTV) with localized bone marrow edema. The patient was treated with acupuncture, pharmacopucture, cupping and herbal medicine. We evaluated patient's progress using range of motion (ROM), EuroQol-5 dimensions (EQ-5D), Oswestry disability index (ODI), numerical rating scale (NRS), patient global impression of change, self-walkable distance. NRS of back pain decreased from 7 to 5, at the same time NRS of lower limb decreased from 4 to 3. EQ-5D score increased from 0.24 to 0.646. ODI score improved 80 to 62. Self-walkable distance and lumbar spine ROM also increased. As a result, clinical improvements were found in a patient. In conclusion, this study shows that Korean medicine treatment can be considered as effective conservative care for LSTV with localized bone marrow edema.

The Effect of Cognitive Rehabilitation Program Combined with Physical Exercise on Cognitive Function, Depression, and Sleep in Chronic Stroke Patients

  • Kim, SoHyun;Cho, SungHyoun
    • Physical Therapy Rehabilitation Science
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    • v.11 no.1
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    • pp.32-42
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    • 2022
  • Objective: This study was conducted to verify the effectiveness of a cognitive rehabilitation program consisting of physical exercises and mental activities for patients with chronic stroke with mild cognitive impairment (MCI). We aimed to investigate how this cognitive rehabilitation program affects patients' cognitive ability, depression, and sleep quality. Design: One group pretest-posttest design Methods: The study was conductedon 12 patients who participated in thecognitive rehabilitation complex exercise program for 16 weeks. The Korean version of the Montreal Cognitive Assessment (MoCA-K), Hamilton Depression Rating Scale (K-HDRS), and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the measured variables before and after study participation. The cognitive rehabilitation complex exercise program included 30 minutes of cognitive exercise and 30 minutes of Brill Exercise. The Wilcoxon signed-rank test was used to compare the variables before and after program participation. Cronbach's ɑ was used to assess the reliability of the test variables. Results: The post-program assessment showed a statistically significant increase in the MoCA-K score, which measures cognitive function (Z=-2.628, P=0.009). For depression ratings, there was a statistically significant decrease in the K-HDRS score (Z=-2.041, P=0.041). For sleep quality, although there was a numerical increase in the PSQI score, the difference was not statistically significant (Z=-0.702, P=0.483). The reliability test confirmed that all the individual test variables exhibited high reliability (cognitive function, 0.859; depression, 0.872; sleep, 0.822). Conclusions: We found that cognitive rehabilitation program used in this study had a positive effect on the cognitive function and depression in patients with chronic stroke with MCI.

Evaluation of Agricultural Drought Disaster Vulnerability Using Analytic Hierarchy Process (AHP) and Entropy Weighting Method (계층화분석 및 엔트로피 가중치 산정 방법에 따른 농업가뭄재해 취약성 평가)

  • Mun, Young-Sik;Nam, Won-Ho;Yang, Mi-Hye;Shin, Ji-Hyeon;Jeon, Min-Gi;Kim, Taegon;Lee, Seung-Yong;Lee, Kwang-Ya
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.3
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    • pp.13-26
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    • 2021
  • Recent drought events in the South Korea and the magnitude of drought losses indicate the continuing vulnerability of the agricultural drought. Various studies have been performed on drought hazard assessment at the regional scales, but until recently, drought management has been response oriented with little attention to mitigation and preparedness. A vulnerability assessment is introduced in order to preemptively respond to agricultural drought and to predict the occurrence of drought. This paper presents a method for spatial, Geographic Information Systems-based assessment of agricultural drought vulnerability in South Korea. It was hypothesized that the key 14 items that define agricultural drought vulnerability were meteorological, agricultural reservoir, social, and adaptability factors. Also, this study is to analyze agricultural drought vulnerability by comparing vulnerability assessment according to weighting method. The weight of the evaluation elements is expressed through the Analytic Hierarchy Process (AHP), which includes subjective elements such as surveys, and the Entropy method using attribute information of the evaluation items. The agricultural drought vulnerability map was created through development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. This vulnerability assessment is calculated the vulnerability index based on the weight, and analyze the vulnerable map from 2015 to 2019. The identification of agricultural drought vulnerability is an essential step in addressing the issue of drought vulnerability in the South Korea and can lead to mitigation-oriented drought management and supports government policymaking.

A Fourier sine series solution of static and dynamic response of nano/micro-scaled FG rod under torsional effect

  • Civalek, Omer;Uzun, Busra;Yayli, M. Ozgur
    • Advances in nano research
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    • v.12 no.5
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    • pp.467-482
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    • 2022
  • In the current work, static and free torsional vibration of functionally graded (FG) nanorods are investigated using Fourier sine series. The boundary conditions are described by the two elastic torsional springs at the ends. The distribution of functionally graded material is considered using a power-law rule. The systems of equations of the mechanical response of nanorods subjected to deformable boundary conditions are achieved by using the modified couple stress theory (MCST) and taking the effects of torsional springs into account. The idea of the study is to construct an eigen value problem involving the torsional spring parameters with small scale parameter and functionally graded index. This article investigates the size dependent free torsional vibration based on the MCST of functionally graded nano/micro rods with deformable boundary conditions using a Fourier sine series solution for the first time. The eigen value problem is constructed using the Stokes' transform to deformable boundary conditions and also the convergence and accuracy of the present methodology are discussed in various numerical examples. The small size coefficient influence on the free torsional vibration characteristics is studied from the point of different parameters for both deformable and rigid boundary conditions. It shows that the torsional vibrational response of functionally graded nanorods are effected by geometry, small size effects, boundary conditions and material composition. Furthermore, for all deformable boundary conditions in the event of nano-sized FG nanorods, the incrementing of the small size parameters leads to increas the torsional frequencies.

A generalized adaptive variational mode decomposition method for nonstationary signals with mode overlapped components

  • Liu, Jing-Liang;Qiu, Fu-Lian;Lin, Zhi-Ping;Li, Yu-Zu;Liao, Fei-Yu
    • Smart Structures and Systems
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    • v.30 no.1
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    • pp.75-88
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    • 2022
  • Engineering structures in operation essentially belong to time-varying or nonlinear structures and the resultant response signals are usually non-stationary. For such time-varying structures, it is of great importance to extract time-dependent dynamic parameters from non-stationary response signals, which benefits structural health monitoring, safety assessment and vibration control. However, various traditional signal processing methods are unable to extract the embedded meaningful information. As a newly developed technique, variational mode decomposition (VMD) shows its superiority on signal decomposition, however, it still suffers two main problems. The foremost problem is that the number of modal components is required to be defined in advance. Another problem needs to be addressed is that VMD cannot effectively separate non-stationary signals composed of closely spaced or overlapped modes. As such, a new method named generalized adaptive variational modal decomposition (GAVMD) is proposed. In this new method, the number of component signals is adaptively estimated by an index of mean frequency, while the generalized demodulation algorithm is introduced to yield a generalized VMD that can decompose mode overlapped signals successfully. After that, synchrosqueezing wavelet transform (SWT) is applied to extract instantaneous frequencies (IFs) of the decomposed mono-component signals. To verify the validity and accuracy of the proposed method, three numerical examples and a steel cable with time-varying tension force are investigated. The results demonstrate that the proposed GAVMD method can decompose the multi-component signal with overlapped modes well and its combination with SWT enables a successful IF extraction of each individual component.