• Food Science and Preservation
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• v.18 no.6
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• pp.993-997
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• 2011

The aims of this research were to determine the proximate composition of various salts and to compare two digestion methods (direct digestion without heating, and microwave digestion) for the determination of the main mineral contents of various salts. Twelve salt samples were divided into three groups of four samples each (imported, Korean gray, and Korean white salts). As a result, the NaCl contents of the Korean white, Korean gray, and imported salts were 85.1, 89.3, and 91.3%, respectively. The salts in the three groups were analyzed for their main mineral contents via AAS. The sodium (Na) content of the Korean white salt was found to be slightly lower than that of the imported salt while the magnesium (Mg) and potassium (K) contents of the Korean white salt were found to be higher than those of the imported salt. The mineral composition (% Na:Mg) obtained using microwave-assisted digestion procedures, and the other dissolutions for the subsequent sample analysis, were 89:1 (for both the imported and Korean gray salts) and 82:3 vs. 81:3 (Korean white salt), respectively. The data regarding the mineral contents and composition of the sun-dried salts obtained through the analysis method of wet digestion and the dissolution procedure were compared, and no significant difference was found between the two datasets. Consequently, in this paper, a direct dissolution procedure is suggested for the analysis of the mineral composition of salt.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1475-1490
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• 2021

Detecting oil spill area using statistical characteristics of SAR images has limitations in that classification algorithm is complicated and is greatly affected by outliers. To overcome these limitations, studies using neural networks to classify oil spills are recently investigated. However, the studies to evaluate whether the performance of model shows a consistent detection performance for various oil spill cases were insufficient. Therefore, in this study, two CNNs (Convolutional Neural Networks) with basic structures(Simple CNN and U-net) were used to discover whether there is a difference in detection performance according to the structure of CNN and distribution characteristics of oil spill. As a result, through the method proposed in this study, the Simple CNN with contracting path only detected oil spill with an F1 score of 86.24% and U-net, which has both contracting and expansive path showed an F1 score of 91.44%. Both models successfully detected oil spills, but detection performance of the U-net was higher than Simple CNN. Additionally, in order to compare the accuracy of models according to various oil spill cases, the cases were classified into four different categories according to the spatial distribution characteristics of the oil spill (presence of land near the oil spill area) and the clarity of border between oil and seawater. The Simple CNN had F1 score values of 85.71%, 87.43%, 86.50%, and 85.86% for each category, showing the maximum difference of 1.71%. In the case of U-net, the values for each category were 89.77%, 92.27%, 92.59%, and 92.66%, with the maximum difference of 2.90%. Such results indicate that neither model showed significant differences in detection performance by the characteristics of oil spill distribution. However, the difference in detection tendency was caused by the difference in the model structure and the oil spill distribution characteristics. In all four oil spill categories, the Simple CNN showed a tendency to overestimate the oil spill area and the U-net showed a tendency to underestimate it. These tendencies were emphasized when the border between oil and seawater was unclear.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.3
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• pp.130-137
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• 2021

Purpose: The various suture techniques can be utilized in order to maximize the keratinized tissue healing around dental implants. The aim of this study is to compare the soft tissue healing pattern between two different suture techniques after implant placement. Materials and Methods: 15 patients with 18 implants were enrolled in this study. Simple implant placement without any additional bone graft was performed. Two different suture techniques were used to tug in the mobilized flap near the healing abutment after paramarginal flap design. Digital intraoral scan was performed at baseline, post-operation, stitch out, and 3 months after operation. The scan data were aligned using multiple points such as cusp, fossa of adjacent teeth, and/or healing abutment. After subtracting scan data at baseline with other time-point results, closed space indicating volume increment of peri-implant mucosa was selected. The volume of the close space was measured in mm³. The volume between two suture techniques at three time-points was compared using nonparametric rank-based analysis. Results: Healing was uneventful in both groups. Both suture technique groups showed increased soft tissue volume immediately after surgery. The amount of volume increment significantly decreased after 3 months (P < 0.001). Flap folding suture group showed higher median of volume increment than interrupted suture group after 3 months without any statistical significance (P > 0.05). Conclusion: After paramarginal flap reflection, the raised flaps stabilized by flap folding suture showed relatively higher volume maintenance after 3-month healing period. However, further studies are warranted.

• The Korean Journal of Gastroenterology
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• v.72 no.6
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• pp.325-328
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• 2018

위마비증(gastroparesis)이나 만성 구역 구토 증후군(chronic unexplained nausea and vomiting)으로 인한 구역과 구토에 대한 치료는 일반적으로 사용하는 위장관 촉진제에 만족스럽지 못한 경우가 많고, 여러 부작용으로 인하여 장기적으로 사용하기 어려워 보다 효과적인 치료 방법이 필요하다. 최근 미국에서 발표된 본 연구는 위마비증이나 연관 증후군 환자에서 구역과 구토 증상을 줄이기 위한 aprepitant(neurokinin-1 receptor antagonist) 치료의 효과를 분석한 것으로, 향후 일반적인 치료에 불응성 위마비증 환자에서 새로운 약제 사용을 시도해볼 수 있어 소개하고자 한다. 본 Aprepitant for the Relief of Nausea (APRON) 연구는 기질적 질환을 배제하기 위하여 최근 2년 이내 위내시경이 정상이며, 적어도 6개월 이상 조기 포만감(early satiety), 식후 만복감(postprandial fullness), 팽만감(bloating) 그리고 명치부 통증(epigastric pain)을 유발하는 증상과 함께 만성적인 구역이 있는 18세 이상의 성인 중 4시간의 위배출 검사를 시행받은 환자를 대상으로 하였다. 객관적인 지표로 0점에서 45점까지 보이는 9-증상 Gastroparesis Cardinal Symptom Index(GCSI)가 2주 이상 총 21점 이상이며, 0-100 mm의 visual analog scale (VAS)의 7일간의 구역 증상 평균 25 mm 이상인 환자를 대상으로 하였다. 일주일에 3일 이상 narcotics를 사용하였거나 와파린이나 pimozide, terfenadien, astemizole, cisapride를 복용하였던 환자, 2배 이상으로 간 효소 수치상승을 보이거나 Child-Pugh score 10점 이상, aprepitant에 알레르기를 보이는 환자는 제외되었다. 그렇지만 metoclopramide나 erythromycin을 안정적으로 사용 중인 환자는 제외되지 않았다. 위배출 검사는 2시간에서 60% 이상 남아 있거나 4시간에서 10% 이상 남아 있는 경우에 지연된 것으로 정의되었으며, 지연된 위배출 검사 결과 자체는 환자의 등록 기준에 포함되진 않았다. 등록 기준에 포함된 환자는 1:1로 무작위 배정되어 하루 한 번 125 mg의 aprepitant 복용군과 위약군으로 나누어져 연구가 진행되었으며, 약제 복용 4주간 2주 간격으로, 그리고 복용 후 2주 뒤까지 구역 증상의 호전 정도와 약제 안전성을 확인하였다. 이러한 효과를 판정하기 위하여 환자가 방문하는 동안 GCSI를 포함한 Patient Assessment of Upper GI Symptoms (PAGI-SYM), Gastrointestinal Symptom Rating Scale, daily VAS, daily diary version of the GCSI 그리고 정신 측정 도구와 삶의 질 도구인 Patient health Questionnaire 15와 Short Form 36 version이 측정되었다. 구역에 대한 aprepitant와 위약의 치료 효과의 일차적 판정은 이전 항암 요법에 대한 aprepitant 연구와 같이 28일 평균 VAS 25 mm 미만이거나 치료 전 7일간의 VAS와 비교하여 28일 치료 기간 동안 25 mm 이상 감소한 경우로 정의하였고, 이차 결과는 구역의 매일 시간, 치료 중 구역이 없는 날짜의 퍼센트, PAGI-SYM score의 개선 등으로 확인하였다. 2013년 4월부터 2015년 7월까지 총 126명의 환자가 등록되어 aprepitant군 63명, 위약군 63명으로 무작위 배정되었다. 전체의 57%인 72명에서 위배출 지연이 보였으며, 나머지 43%에서는 정상 또는 빠른 위배출 소견을 보여 만성적으로 설명할 수 없는 구역과 구토에 포함된 환자군으로 확인되었다. 또한 29%에서 당뇨를 가지고 있었으며, 8%에서 수면제를 사용하고 있었다. 최종적으로 aprepitant군은 59명, 위약군은 63명이 연구를 끝까지 종료하였다. 일차 결과에서 aprepitant 군 46%, 위약군 40%의 구역 호전을 보여 두 치료군 간에 통계적으로 의미 있는 차이는 보이지 않았다(상대 위험도 1.2, 95% CI: 0.8-1.7; p=0.43). 그러나 일차 분석의 두 가지 척도(28일 평균 VAS 25 mm 미만과 기저 VAS보다 평균 28일 VAS의 25 mm 이상 감소)를 모두 함께 고려한 민감도 분석에서는 aprepitant군이 37% (22/59)로 위약군의 17%(11/63)에 비하여 통계적으로 의미 있는 구역의 호전을 보였다(상대 위험도 2.1, 95% CI: 1.1-4.1; p=0.01). 또한 이차 분석을 살펴보면 aprepitant군에서 PAGI-SYM 중증도 지수로 확인하였을 때, 구역(1.8 vs. 1.0; p=0.005)과 구토(1.6 vs. 0.5; p=0.001)의 중증도 및 매일 구역 시간의 감소를 보였고, 28일 동안 구역이 없는 날짜의 퍼센트 증가 소견을 보였다. 다른 이차 결과 분석에서 aprepitant군이 PAGI-SYM 중증도 지수의 GCSI 종합 점수(1.3 vs. 0.7; p=0.001), 상당한 증상호전, 구역 구토의 세부 점수, 팽만감 세부 점수 그리고 위식도 역류 증상 점수에서 호전을 보였고, 매일 일기로 표현한 daily diary version of the GCSI에 상복부 통증 중증도, 전체 증상 그리고 Gastrointestinal Symptom Rating Scale의 종합 점수에서 호전을 보였다. 연구 중 발생한 부작용은 주로 경증과 중등도 정도의 부작용이 주로 발생하였지만, aprepitant군(35% vs. 17% 위약군, p=0.04)에서 더 많이 발생하였다. 결론적으로 위마비증 또는 위마비증 유사 증후군으로 인한 만성 구역 및 구토 환자의 무작위 시험에서 aprepitant는 VAS 점수를 통한 주요 결과를 분석하였을 때는 구역의 중증도를 호전시키지 못하였지만 다른 이차적 결과에 대해서는 위약군에 대하여 호전 소견을 보였다. 따라서 aprepitant에 효과적인 반응을 보이는 위마비증 환자를 감별하는 추가 임상시험이 필요할 것으로 판단된다.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.43-49
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• 2019

Purpose : We apply the Layered Rescanning PBS designed to complement the Pencil Beam Scanning(PBS), which is vulnerable to moving organs with the Moving Phantom, and compare the homogeneity with the single scan PBS. Methods and materials: Matrix X (IBA, Belgium) and Moving Phantom (standard imaging, USA) were used. A dose of 200 cGy was measured in the AP direction on a hypothetical tumor $10{\times}10{\times}5cm$. The plan type was planned as 4 kinds of sinlge scan PBS, rescan number 4, 8, 12 times. Were measured three times for each types. During the measurement, the respiratory cycle of the Moving Phantom was generally set to 4 seconds per cycle, and the movement radius in the S-I direction was set to 2 cm. In addition, beam on time was measured. Results : The mean values of $D_{max}$ in the PTV were $246.47{\pm}18.8cGy$, $223.43{\pm}8.92cGy$, and $222.47{\pm}7.7cGy$, $213.9{\pm}6.11cGy$ and the mean values of $D_{min}$ were $165.53{\pm}4.32cGy$, $173.13{\pm}11.94cGy$, $184.13{\pm}8.04cGy$, $182.67{\pm}4.38cGy$ and the mean values of $D_{mean}$ $192.77{\pm}6.98cGy$, $196.7{\pm}4.01cGy$, $198.17{\pm}4.96cGy$, $195.77{\pm}3.15cGy$ respectively. As the number of rescanning increased, the Homogeneity Index converged to 1. The beam on time was measured as 2:15, 3:15, 4:30, 5:37 on average. In the measurement process, in the low dose layer of the MU, the problem was found that it was not rescanned as many times as the set number of rescan. Conclusions : In the treatment of tumors with long-term movements, the application of layered rescanning PBS showed a more uniform dose distribution than single scan PBS. And as the number of rescan increase, the distribution of homogeneity is uniform. Compared with single scan plan and 12 rescan plan, HI value was improved by 0.32. Further studies are expected to be applicable to patients who can not be treated with respiratory synchronous radiation therapy.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.351-373
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• 2019

The cold eddies around the Ulleung Basin in the East Sea were identified from satellite altimeter sea level data using the Winding-Angle method from 1993 to 2015. Among the cold eddies, the Dokdo Cold Eddies (DCEs), which were formed at the first meandering trough of the East Korea Warm Current (EKWC) and were pinched off to the southwest from the eastward flow, were classified and their migration patterns were analyzed. The vertical structures of water temperature, salinity, and flow velocity near the DCE center were also examined using numerical simulation and observation data provided by the Hybrid Coordinate Ocean Model and the National Institute of Fisheries Science, respectively. A total of 112 DCEs were generated for 23 years. Of these, 39 DCEs migrated westward and arrived off the east coast of Korea. The average travel distance was 250.9 km, the average lifespan was 93 days, and the average travel speed was 3.5 cm/s. The other 73 DCEs had moved to the east or had hovered around the generated location until they disappeared. At 50-100 m depth under the DCE, water temperature and salinity (T < $5^{\circ}C$, S < 34.1) were lower than those of ambient water and isotherms made a dome shape. Current faster than 10 cm/s circulates counterclockwise from the surface to 300 m depth at 38 km away from the center of DCE. After the EKWC separates from the coast, it flows eastward and starts to meander near Ulleungdo. The first trough of the meander in the east of Ulleungdo is pushed deep into the southwest and forms a cold eddy (DCE), which is shed from the meander in the south of Ulleungdo. While a DCE moves westward, it circumvents the Ulleung Warm Eddy (UWE) clockwise and follows U shape path toward the east coast of Korea. When the DCE arrives near the coast, the EKWC separates from the coast at the south of DCE and circumvents the DCE. As the DCE near the coast weakens and extinguishes about 30 days later after the arrival, the EKWC flows northward along the coast recovering its original path. The DCE steadily transports heat and salt from the north to the south, which helps to form a cold water region in the southwest of the Ulleung Basin and brings positive vorticity to change the separation latitude and path of the EKWC. Some of the DCEs moving to the west were merged into a coastal cold eddy to form a wide cold water region in the west of Ulleung Basin and to create a elongated anticlockwise circulation, which separated the UWE in the north from the EKWC in the south.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.1-11
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• 2021

The purpose of this study is to find out the main factors affecting air quality in urban physical space factors, and provide clues for environmental improvement. Nine monitoring stations in China's industrial city, Changchun, collected AQI concentration data from January 1, 2018 to December 31, 2019. This paper analyzes the types and distribution characteristics of urban physical facilities within a radius of 300m with the detection station as the center. The monitoring station is divided into three groups, and the difference in floating dust concentration among the three groups in different seasons is analyzed. The results show that AQI concentration is the highest in spring and winter, followed by summer, and the lowest in autumn. The place with the highest concentrations of AQI in spring are F (93.00), D (91.10), I (89.20), in summer are D (69.05), A (67.89), B (84.44), in autumn are I (62.80), G (60.84), D (53.27), D (53.27), in winter are I (95.82), H (95.60), f (94.04). Through SPSS analysis, it shows that the air index in a space with a diameter of 600 meters is related to forest land, grassland, bare land, water space, tree height, building area (average value), and building volume (average value). According to the statistical analysis results of spring and winter with the most serious pollution, forest land area (43,637m², 15.44%) and water surface area (18,736m², 6.63%) accounted for the majority, and group 1 (A, B, C) with the least average building area (448m², 0.17%) and average building volume (10,201m²) had the lowest pollution concentration. On the contrary, group 2 (D, E, F) had the highest AQI concentration, with less or no woodland (1,917m², 0.68%) and water surface area (0m², 0%), and the highest average building area (1,056m², 0.37%) and average building volume (17,470m³). It is confirmed that the characteristics of the area with the highest AQI concentration are that the more the site ratio of tree height above 12m, the smaller the site ratio of bare land, and the lower the pollution degree. On the contrary, the larger the area of bare land, the higher the pollution degree. By analyzing the characteristics of nine monitoring stations in Changchun, it can be seen that the air quality brought by the physical characteristics of urban space is closely related to the above factors.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.181-189
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• 2021

Purpose: The purpose of this study is to investigate the stress response and sleep state of the new patients who visit the hospital for prosthodontic treatment due to tooth loss to make reference to further treatment direction. Materials and methods: Examinations, consultations, and surveys were conducted on 236 patients (94 males, 142 females, and 24-86 years old), who newly registered at the department of prosthodontics at Pusan national university hospital, for 2 years from 2018. The number of remaining teeth, edentulous arch, possibility of mastication, and future prosthetic treatment directions were recorded. The visual analogue scale (VAS), stress response inventory (SRI) and Insomnia severity index (ISI) were used as tools to measure patient's subjective discomfort, stress response, and sleep status. Results: Among the entire prosthodontic patient group, the average value of 'fatigue' was significantly higher among the 7 items of SRI, and the value of 'aggression' was significantly lower (P<.001). There are a significant difference between the edentulous and full dentition in the oral discomfort value measured by VAS (P=.004). In cases where less than 20 teeth remain, mastication is impossible, and patients who are planning treatment with removable prostheses, VAS value and 'depression' and 'fatigue' values in SRI were higher than those in the reverse case (P<.05). The patients showed severe level in VAS value have high value of 'tension', 'somatization', 'depression', 'fatigue'and 'frustration'in SRI than non-serious patients (P<.05). Clinical insomnia occurred in 11.4% of all patients, and women had significantly lower sleep quality than men (P=.044). Patients with insomnia showed significantly higher scores on the VAS value and all 7 SRI items than those of normal sleepers (P<.05). Conclusion: The new prosthetics had high 'fatigue' value among the 7 items of SRI. The oral condition, number of residual teeth and mastication function and clinical insomnia affected oral discomfort and the stress response.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.153-160
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• 2018

Purpose : We retrospectively analyzed doses of each radiation therapy technique used in the treatment for left breast cancer patients after partial mastectomy through dose results for normalorgans and tumor volume to use this as a clinical reference for radiation therapy of domestic left breast cancer patients. Materials and Methods : 40 patients who underwent partial mastectomy on left breast cancer were classified in 3 treatment methods. The treatment plan was evaluated by HI(homogeneity index), $D_{95%}$, and CI(conformity index), and the $V_{hot}$ for gross tumor volume and clinical target volume of each treatment method. In Cyberknife treatment, tumor volume was the same as high dose volume in the other techniques, so no consideration was given to clinical target volume. Treatment plan evaluation for normal organs were evaluated by mean dose on ipsilateral lung, heart, left anterior descending artery, opposite breast and lung, and non-target tissue. Result : Treatment with volumetric arc radiotherapy(VMAT) showed $95.84{\pm}0.75%$ of $D_{95%}$ on the clinical target volume, significantly higher than that of 3D-CRT. The $D_{95%}$ value of the total tumor volume was slightly higher than the other treatments. In Cyberknife treatment, the dose to the normal organs was significantly lower than other treatments. Overall, the maximum dose and mean dose to the heart were $26.2{\pm}6.12Gy$ and $1.88{\pm}0.2Gy$ in VMAT treatment and $20.25{\pm}9.35Gy$ and $1.04{\pm}0.19Gy$ in 3D-CRT therapy, respectively. Conclusion : In comparison on 3D-CRT and VMAT, most of the dosimetric parameters for the evaluation of the treatment plan showed similar values, so that there is no significant difference in treatment plan evaluation. It is possible to select the treatment method according to the patient's anatomical structure or possibility of breath control. Cyberknife treatment is very useful treatment for normal organs because of its accurate dose exposure to the tumor volume However, it has restrictions to treat the local area, to have relatively long treatment time and to involve invasive procedure.

• Journal of the Korean Geotechnical Society
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• v.37 no.3
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• pp.19-30
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• 2021

The presence of the hydrate-bearing sediments in Ulleung Basin of South Korea has been confirmed from previous studies. Researches on gas production methods from the hydrate-bearing sediments have been conducted worldwide. As production mechanism is a complex phenomenon in which thermal, hydraulic, and mechanical phenomena occur simultaneously, it is difficult to accurately conduct the productivity and stability analysis of hydrate bearing sediments through lab-scale experiments. Thus, the importance of numerical analysis in evaluating gas productivity and stability of hydrate-bearing sediments has been emphasized. In this study, the numerical parametric analysis was conducted to investigate the effects of the bottom hole pressure and the depressurization rate on the gas productivity and stability of hydrate-bearing sediments during the depressurization method. The numerical analysis results confirmed that as the bottom hole pressure decreases, the productivity increases and the stability of sediments deteriorates. Meanwhile, it was shown that the depressurization rate did not largely affect the productivity and stability of the hydrate-bearing sediments. In addition, sensitivity analysis for gas productivity and stability of the sediments were conducted according to the depressurization rate in order to establish a production strategy that prevents sand production during gas production. As a result of the analysis, it was confirmed that controlling the depressurization rate from a low value to a high value is effective in securing the stability. Moreover, during gas production, the subsidence of sediments occurred near the production well, and ground heave occurred at the bottom of the production well due to the pressure gradient. From these results, it was concluded that both the productivity and stability analyses should be conducted in order to determine the bottom hole pressure when producing gas using the depressurization method. Additionally, the stress analysis of the production well, which is induced by the vertical displacements of sediments, should be evaluated.