• 한국구조물진단유지관리공학회 논문집
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• 제15권5호
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• pp.160-168
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• 2011

성수대교 삼풍백화점 붕괴사고 등을 계기로 유지관리 분야의 중요성이 대두되면서 1995년 시설물의안전관리에관한특별법이 제정되어 점검 진단이 실시되는 등 본격적인 유지관리체제가 시작됐다. 그러나 점검 진단의 역사가 일천한 관계로 점검 진단에 대한 기술수준이 낮았고 연구 성과 또한 미흡하여 부실 점검 진단에 대한 우려가 상존해 있었다. 이에 2002년 평가제도가 도입되면서 부실 점검 진단 비율이 지속적으로 낮아져 왔다. 그러나 최근 점검 진단 실시결과 평가실적에 따르면 향후 부실 점검 진단비율이 더 이상 낮아지기 힘든 경향을 보이고 있다. 이를 계기로 부실 점검 진단과 관련하여 관련기관의 설문조사와 메커니즘 측면에서 고찰하므로서, 부실 점검 진단이 초래되는 근원적인 문제점을 나열하였고, 이를 바탕으로 현행 평가제도의 개선방향을 제시 하고자 하였다.

• Journal of Nutrition and Health
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• 제35권5호
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• pp.531-543
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• 2002

To assess the dietary therapy compliance of non-insulin-dependent diabetes mellitus (NIDDM) patients living in Daegu, we evaluated diet adequacy levels by index of nutritional quality (INQ), nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and dietary variety score (DVS) with food exchange system and Korean recommended dietary allowances (KRDA). One day dietary intake was measured by 24 hour recall method for 229 subjects over 20 years of age. Average daily energy intake was 1444 kcal. The relative ratio of carbohydrate, protein and fat in terms of energy intake was 69.4：14.5：16.0. The nutrient adequacy ratio (NAR) for Vitamin A, B$_2$, calcium were lower than 0.5 and MAR was 0.65. It appeared that the consumption of each food group as compared to prescribed food exchange unit was insufficient, in the order of dairy group (10.2 $\pm$ 25.2%), fruits group (58.2 $\pm$ 71.2%) and oils & fats group (42.9 $\pm$ 42.0%). The dietary variety score (DVS) was evaluated as an useful tool for diabetes' meal management when we accept minimum intake as 0.3 of food exchange unit. We found significant correlation between food groups and anthropometric indices: cereals group and % total body fat (r = 0.251, p < 0.01), meat group and waist circumference (r = 0.241, p < 0.01), vegetables group and WHR(r = 0.139, p < 0.05), and oils poop and WHR(r = 0.165, p < 0.05). from these results, we concluded that overall status of dietary intake of NIDDM patients in Daegu area was insufficient not only in quality but also in quantity. It is suggested that nutrition education for NIDDM patients should stress on balanced food consumption to meet proscribed amount by six food group to improve the inadequacy of dietary status.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.29-31
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• 2012

The effects of combustion parameters on the characteristics of a steam-methane reformer. The reformer system was numerically simulated using a simplified two-dimensional axisymmetric model domain with an appropriate user-defined function. The fuel ratio, defined as the ratio of methane flow rate in the combustor to that in the reactor, was varied from 20 to 80%. The equivalence ratio was changed from 0.5 to 1.0. The results indicated that as the fuel ratio increased, the production rates of hydrogen and carbon monoxide increased, although their rates of increase diminished. In fact, at the highest heat supply rates, hydrogen production was actually slightly decreased. Simulations showed that equivalence ratio of 0.7 yielded the highest steam-methane mixture temperature despite a 43% higher air flow rate than the stoichiometric flow rate. This means that the production of hydrogen and carbon monoxide can be increased by adjusting the equivalence ratio, especially when the heat supply is insufficient.

• Safety and Health at Work
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• 제12권2호
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• pp.225-229
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• 2021

Background: The socioeconomic burden of musculoskeletal disorders (MSDs) is significant, and kitchen work is a high-risk occupation for MSDs due to the intensive manual workload and repetitive movements that are involved. However, there are very few studies on MSDs and rest breaks as a workplace intervention among kitchen workers. This study examined the relationship between insufficient rest breaks and increased MSD risk among Korean kitchen workers. Methods: Sociodemographic and occupational factors of 1,909 kitchen workers were collected from the 3rd-4th Korean Working Conditions Survey data. Five items on rest breaks at work were categorized into two groups, "sufficient" and "insufficient." The number of MSDs and work-related MSDs (WMSDs), an outcome variable, was obtained from the sum of MSDs/WMSDs in three anatomical sites (back, neck, and upper limb, lower limb). The association between rest breaks and MSDs was estimated using zeroinflated negative binomial analyses, with adjustments for age, education level, and weekly working hours, and the analyses were stratified by sex. Results: After adjustment, significant associations were found between insufficient rest breaks and an increased risk of MSDs (odds ratio [OR] 1.68 95% confidence interval [CI] 1.11-2.54) and WMSDs (OR 1.40 95% CI 1.01-1.96) among female kitchen workers. Insufficient rest breaks were significantly associated with MSDs in female kitchen workers in all three anatomical sites. Conclusion: This study emphasizes the need for rest breaks as a workplace intervention for preventing MSDs in kitchen workers. Further studies to reveal the causality of this relationship are required.

• 가족자원경영과 정책
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• 제13권1호
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• pp.61-81
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• 2009

The purpose of this study was to investigate the policy demands of the family sector for work-family balance, with a focus on the child care and household labor provisions. For empirical analysis, data were collected from 197 dual-income families with at least one young child under age 10 in the metropolitan area via self-administered questionnaires. The major findings of this study were as follows. First, child care provisions for working mothers and fathers were insufficient and unfair, and the ratio of child care provisions offered by familial child care network was high. The characteristics of child care provisions for working parents were associated with family structure, working conditions, and demographic variables. Second, household labor provisions for working mothers and fathers were also insufficient and unfair, and the ratio of socialization was high. Third, the level of family satisfaction varied by the level of child care and household labor provisions, respectively, controlling family structure, working conditions, and demographic variables. The empirical results of the study provided policy implications for work-family balance.

• Smart Structures and Systems
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• 제12권2호
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• pp.137-155
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• 2013

Brittle fracture of structures excited by earthquakes can be prevented by adding a tuned mass damper (TMD). This TMD must be optimum and suitable to the physical conditions of the structure. Compressive strength of concrete is an important factor for brittle fracture. The application of a TMD to structures with low compressive strength of concrete may not be possible if the weight of the TMD is too much. A heavy TMD is dangerous for these structures because of insufficient axial force capacity of structure. For the preventing brittle fracture, the damping ratio of the TMD must be sufficient to reduce maximum shear forces below the values proposed in design regulations. Using the formulas for frequency and damping ratio related to a preselected mass, this objective can be only achieved by increasing the mass of the TMD. By using a metaheuristic method, the optimum parameters can be searched in a specific limit. In this study, Harmony Search (HS) is employed to find optimum TMD parameters for preventing brittle fracture by reducing shear force in additional to other time and frequency responses. The proposed method is feasible for the retrofit of weak structures with insufficient compressive strength of concrete.

• 한국응급구조학회지
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• 제18권1호
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• pp.107-116
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• 2014

Purpose : The purpose of this study is to demonstrate the effectiveness of using a digital sensor device during CPR by analyzing the results from that chest compressions with a digital sensor device are applied to cardiac arrest patients. Methods : This study analyzed the results from the experiment that 42 people were selected randomly among Korean 119 rescuers, and they divided into the experimental group using a digital sensor device and the control group only using their hands, then they had been observed to conduct chest-compressions to mannequins for 10 minutes. Results : The results were found that compression depth in both the control and experimental group was gradually decreased over time, but the experimental group not only kept the depth but also maintained the speed of chest-compressions close to 100 times a minute. In addition, due to the use of the digital sensor device, the insufficient recoil ratio of chest-compressions was significantly reduced. Conclusion : The results show that conducting chest-compressions with a digital sensor device keeps the compression-death, maintains the speed of chest-compression properly and makes the insufficient relaxation ratio of chest-compressions reduce significantly.

• Wind and Structures
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• 제24권4호
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• pp.307-331
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• 2017

Free transverse vibration of shear deformable super-elliptical plates with uniform thickness was studied based on Mindlin plate theory using finite element method. Quadrilateral isoparametric elements were used in the paper. Sensitivity analysis was made to determine the influence of the thickness, the aspect ratio, and the shape of the plate on the natural frequency. Accuracy of the results computed in the current study was validated by comparing them with the solutions available in the literature. The results reveal that the frequencies of clamped super-elliptical plates lie in the range bounded by elliptical and rectangular plates irrespective of the aspect ratio, and furthermore, the frequency decreases if the super-elliptical power increases. A similar trend was observed for simply supported plates with high aspect ratio. The free vibration response for the first and the second symmetric-antisymmetric (SA) modes were found to be different for high aspect ratio. The results reveal that using insufficient number of degrees of freedom results in finding a totally different relation between the super-elliptical power and the frequency.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.154-157
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• 2001

Through this study we investigated the causes of bottom crack. We then redesigned petaloid bottom to prevent bottom crack. We examined the material property variations according to the stretch ratio of PET and analyzed stretches of bottom in blowing processes. We also performed crack test to observe a crack phenomena. The effective stress and maximum principal stress were examined by computer simulation. We concluded that the bottom crack occurs because of not only insufficient strength of material due to the insufficient stretch of PET but also coarse design of petaloid shape. The highest maximum principal stress occurred at valley in petaloid bottom of bottle and this strongly affected the crack in bottom. We redesigned petaloid shape to minimize maximum principal stress, and this result in increasing the crack resistance.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.223-224
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• 2017

In this study, various materials such as epoxy material, urethane material, cement material, and acrylic material are used to solve the water leakage occurring in underground structures. However, in the reality that the durability is insufficient and the effect is insufficient, it is aimed to improve the repairing effect by using cement and acrylics in combination. As a first study, we tried to verify the performance of improve the performance by checking the product properties according to the composition ratio of polyacrylic resin. Polyacrylic resin is evaluated in three different composition ratios. When the material is selected for polyacrylic resin, it is applied to the field to understand the maintenance effect and durability.